挖掘机 外文翻译 外文文献中英翻译

挖土机英语作文The excavator, also known as a digger or a backhoe, is a heavy-duty construction machine that is used for digging, lifting, and moving large amounts of earth, rocks, and debris. It is one of the most essential machines in the construction industry and is widely used in various applications such as mining, building construction, and road construction.The excavator has a long boom arm with a bucket at the end that can be rotated 360 degrees. The bucket is attached to the arm with a hydraulic system that allows it to move up and down and open and close. The excavator is operated from a cab located on top of the machine that provides a clear view of the work area.The excavator has a wide range of applications in the construction industry. It is used to dig trenches, foundations, and holes for buildings and other structures. It is also used to remove earth and rocks from construction sites and to load them onto trucks for transport. In addition, the excavator is used to clear land forconstruction projects and to demolish old buildings and structures.The excavator is also used in the mining industry to extract minerals and ores from the ground. It is used to dig large open-pit mines as well as underground mines. The excavator is ideal for mining operations because of its ability to dig deep into the earth and its powerful hydraulic system that can lift heavy loads.The excavator is also used in the agricultural industry to dig irrigation canals and to prepare land for planting. It is used to dig trenches for drainage systems and to remove rocks and debris from fields. The excavator is also used to clear land for new agricultural projects and to demolish old buildings and structures on farms.The excavator is a versatile machine that can be equipped with various attachments to perform different tasks. For example, it can be equipped with a hydraulic hammer or a concrete breaker to break up concrete and other hard materials. It can also be equipped with a grapple or a clamshell bucket to pick up and move large objects.The excavator is an expensive machine to purchase and maintain. It requires regular maintenance and repairs to keep it in good working condition. The hydraulic system is particularly important and requires regular servicing to prevent leaks and other problems.In conclusion, the excavator is an essential machine in the construction industry. It is widely used in various applications and is capable of performing a wide range of tasks. The excavator is a versatile machine that can be equipped with various attachments to perform different tasks. It is a powerful machine that requires regular maintenance and repairs to keep it in good working condition.。

Hydraulic Excavators液压挖掘机7．1Overview概述7.1.1 Basic Concept 基本概念An excavator is an engineering vehicle consisting of an articulated arm (boom, stick), bucket and cab mounted on a pivot (a rotating platform) atop an undercarriage with tracks or wheels. Their design is a natural progression from the steam shovel.挖掘机是一种由铰接臂杆（动臂和斗杆）、铲斗和安装于履带或轮式底盘上的转盘（一种旋转平台）所组成的工程机械（车辆）。

挖掘机是在蒸汽铲的基础上自然发展起来的。

The history of heavy excavating machinery began in 1835 when the dipper shovel was invented to excavate hard soil and rock and to load trucks. Of course, with the invention of gasoline-and diesel-powered vehicles, construction equipment became even more adaptable. Most construction equipment is powered by diesel engines, although electric-power, battery power, and propane tanks are used on specialized equipment.重型挖掘机的历史始于1835年，当时发明了拉铲式挖掘机用于开挖坚硬的土石方及装载卡车。

介绍挖掘机的英语小作文Excavator Introduction。

Excavators are heavy construction equipment that are used for various purposes such as digging, demolition, mining, landscaping, and more. They are also known as diggers, backhoes, or mechanical shovels. Excavators come in different sizes and types, ranging from small compact models to large hydraulic machines.The basic structure of an excavator consists of a cab, an arm, a boom, and a bucket. The cab is the operator's compartment, which is located on top of the machine and provides a clear view of the working area. The arm is the part of the excavator that extends out from the cab and is used to control the movement of the boom and the bucket. The boom is the long arm that extends from the cab and is used to reach high places or dig deep holes. The bucket is the part of the excavator that is used to scoop up dirt, rocks, and other materials.Excavators are powered by either diesel or electric engines, and they use hydraulic systems to operate the arm, boom, and bucket. The hydraulic system consists of a pump, a motor, and a series of hoses and valves that control the flow of fluid to the different parts of the machine.Excavators are used in a variety of industries, such as construction, mining, forestry, and agriculture. They are often used to dig foundations for buildings, clear land for new construction projects, and excavate mines and quarries. They can also be used to remove trees and other vegetation, grade land, and build roads and bridges.In conclusion, excavators are versatile machines that are used for a wide range of purposes. They are essential tools in the construction, mining, and forestry industries, and they have revolutionized the way we build and develop our communities. With their powerful engines and hydraulic systems, excavators are capable of performing some of the most challenging tasks in the world of heavy machinery.。

英语介绍挖掘机作文Title: Introduction to Excavators。

Excavators, also known as diggers or hydraulic excavators, are heavy construction equipment used primarily for digging and moving large amounts of earth, soil, debris, and other materials. They are essential machines in various industries such as construction, mining, forestry, and demolition. In this essay, we will delve into the functionalities, components, and significance of excavators in modern construction and engineering projects.At the core of an excavator lies its hydraulic system, which powers its movements and functions. The hydraulic system comprises hydraulic cylinders, hydraulic motors, hydraulic pumps, and hydraulic fluid. These components work together to provide the excavator with the strength and precision needed to perform various tasks efficiently.The main parts of an excavator include the boom, arm,and bucket. The boom is the large, telescopic arm that extends from the excavator's chassis and provides vertical movement. Attached to the end of the boom is the arm, which controls the horizontal movement and positioning of the bucket. The bucket, typically made of hardened steel, is the attachment used for digging, scooping, and lifting materials.Excavators come in various sizes, ranging from compact mini-excavators suitable for small-scale projects to large hydraulic excavators used in major construction endeavors. The size of the excavator depends on the specific requirements of the project, including the depth and scope of excavation, accessibility of the site, and environmental constraints.One of the key advantages of excavators is their versatility. They can be equipped with different attachments to perform a wide range of tasks beyond excavation, including demolition, landscaping, material handling, and forestry work. Common attachments include hydraulic breakers for breaking concrete and rock, grapplesfor handling bulky materials, and augers for drilling holes.The operation of an excavator requires skill and precision. Operators control the excavator using joysticks and pedals located in the cab. Modern excavators are equipped with advanced technology such as GPS systems and onboard computers, which enhance accuracy, efficiency, and safety during operation.Excavators play a crucial role in various stages of construction projects. During site preparation, excavators are used to clear land, remove obstacles, and excavate trenches for foundations. In building construction, theyare employed for digging footings, backfilling, and lifting heavy materials. In road construction, excavators are usedto excavate ditches, grade surfaces, and install drainage systems.In addition to construction, excavators are widely used in mining operations for extracting minerals and ores from the earth. Their powerful digging capabilities make them indispensable in open-pit mining, quarrying, and dredgingoperations. Excavators are also utilized in forestry operations for clearing land, harvesting timber, and constructing logging roads.In conclusion, excavators are versatile and indispensable machines in the field of construction and engineering. Their ability to perform a wide range of tasks with precision and efficiency makes them invaluable assetsin various industries. As technology continues to advance, excavators will likely evolve to become even more efficient, environmentally friendly, and safer to operate, further cementing their status as essential equipment in modern construction projects.。

描写挖掘机施工的英语作文Excavation: The Foundation of Modern Construction.In the realm of civil engineering, excavation marks the genesis of countless infrastructure projects, laying the groundwork for towering skyscrapers, sprawling highways, and subterranean marvels. It involves the intricate removal of earth, rock, or other materials from a designated area, creating a void essential for the construction ofstructures or the installation of underground utilities.Types of Excavations.The scope of excavation projects varies widely, each requiring specialized techniques and equipment. Common types include:Cut-and-fill excavation: Involves removing and transporting soil or rock from higher elevations to fill lower areas, creating a level surface for construction.Trench excavation: Consists of digging narrow, deep trenches for the placement of pipelines, cables, or foundations.Basement excavation: Removes soil and rock to createan underground space below a building, providing additional living area or storage.Tunnel excavation: Involves the creation of underground passages for transportation, utility lines, or drainage systems.Excavation Methods.The choice of excavation method depends on the soil conditions, project scale, and environmental considerations. Primary methods include:Mechanical excavation: Utilizes heavy machinery suchas excavators, backhoes, and bulldozers to remove soil and rock in large volumes.Hydraulic excavation: Injects high-pressure water jets into the excavation area, breaking down soil and pumping it out as slurry.Blasting: Uses explosives to fracture rock and remove large quantities of material in restricted areas.Hand excavation: Utilizes manual labor with hand tools such as shovels, picks, and crowbars for small-scale excavations in sensitive or confined spaces.Excavation Planning and Safety.Proper planning is paramount for successful excavation projects. Factors to consider include:Soil analysis: Conducting geotechnical studies to determine soil composition, moisture content, and bearing capacity.Site layout: Determining the location of excavation,spoil disposal areas, and access routes for equipment and materials.Shoring and bracing: Designing and installingtemporary structures to prevent excavation walls from collapsing.De-watering: Managing groundwater infiltration through pumping or drainage systems to maintain excavationstability.Safety is of utmost importance in excavation operations. Workers must adhere to strict safety protocols, including:Wearing proper personal protective equipment (PPE)such as hard hats, gloves, and safety glasses.Maintaining a safe distance from excavation edges and operating machinery.Inspecting equipment regularly and reporting any defects or malfunctions.Following established excavation procedures and adhering to hazard control measures.Environmental Considerations.Excavation projects can have significant environmental impacts. To mitigate these impacts, contractors implement measures such as:Erosion and sediment control: Using sediment barriers, silt fences, and mulches to prevent soil erosion and sedimentation in waterways.Air quality management: Employing dust suppression techniques such as water spraying or chemical treatment to minimize particulate emissions.Noise attenuation: Utilizing noise barriers, blankets, or enclosures to reduce noise levels generated by excavation equipment.Waste management: Disposing of excavated soil and rock in designated areas and recycling materials whenever possible.Conclusion.Excavation, the art of removing earth for construction purposes, is a fundamental aspect of modern civil engineering. It requires careful planning, sophisticated techniques, and diligent safety measures to create the foundation for countless infrastructure projects. By understanding the types of excavations, methods, planning considerations, safety protocols, and environmental implications involved, we can appreciate the complexity and importance of this essential construction process.。

挖掘机外文翻译外文文献中英翻译Excavator Translation: English Translation of Foreign LiteratureAbstract:The translation of foreign literature plays a significant role in acquiring knowledge and broadening horizons. In this article, we will explore the translation of foreign literature related to excavators. By analyzing various examples, we aim to provide an insightful understanding of the translation process and techniques involved in conveying the essence of foreign texts to the target language.1. IntroductionThe field of construction machinery presents numerous challenges when it comes to translation due to the technical nature of the content. Translating related literature helps engineers and professionals gain access to international best practices, safety guidelines, and advancements. One of the key areas within construction machinery is excavators, which serve as the focus of this article's English translation of foreign literature.2. Historical Background and EvolutionBefore delving into translations of foreign literature, it is essential to understand the historical background and evolution of excavators. The first excavators can be traced back to ancient civilizations such as the Egyptians and Greeks. Through detailed research and analysis, these ancient excavation methods have gradually evolved into the sophisticated machinery used today.3. Translation Techniques for Excavator-Related TerminologyTranslating technical terms accurately is crucial in preserving the integrity and clarity of the original text. When it comes to excavators, some terms might not have a direct equivalent in the target language. In such cases, the translator must employ various techniques like borrowing, calque, explanation, or using a closest possible translation. Balancing accuracy and readability is a crucial aspect of this translation process.4. Examples of Translated Excavator LiteratureTo demonstrate the translation techniques mentioned earlier, several examples will be provided in this section. These examples will range from user manuals, safety guidelines, to technical specifications and advancements. Through examining these examples, readers will gain insight into the specific challenges faced during translation and the strategies usedto overcome them.5. Cultural Considerations in Excavator TranslationsIn addition to technical accuracy, cultural considerations play a vital role in translating excavator literature. Different cultures may have varying perceptions and terminologies related to construction machinery. Translators need to be aware of cultural nuances to ensure that the translated materials are not only accurate but also culturally appropriate for the target audience.6. ConclusionIn conclusion, the translation of foreign literature on excavators is of great importance in the field of construction machinery. By accurately conveying the technical details, safety guidelines, and advancements fromforeign texts, engineers and professionals can broaden their knowledge and stay updated with international practices. The translation process involves employing various techniques and considering cultural aspects. As a result, it is crucial for translators to possess both technical expertise and cultural sensitivity when undertaking such translations.Through this article, we have explored the significance of excavator translation, the challenges faced, and the techniques employed. It is the bridge that connects language barriers, facilitates learning, and fosters advancements in the field.。

外文资料Application of tunneling machine in mining and tunnelBoring machine for convenient mining hard rock and provides a unique capability. Therefore, widely is applied in underground, mining and tunneling. In the successful use of the tunnelling machine a a decisive issue is improve machine productivity and reduce the mining cost of reliability analysis. This article presents and discusses the Colorado School of geomechanics research recently completed work for mining in the history of the use of data as a dynamic performance model. This model is from different roadheader under various geological conditions of work based to an extensive collection of data. This article also discussed the development and content of the database The prediction of cutting rate and energy consumption of the boring machine is the program.At present, the mechanical mining system broad use in mining and civil construction, and the main trend is to improve productivity and reduce the cost, the main benefit is to reduce land possession of; at the same time, enhance the safety of workers. These are mainly depending on machine performance of a substantial increase in, the reliability has caused the expansion of mining market and the level of workers has been improved.Boring machine is a kind of widely used in underground soft rock tunneling machine, especially for those sedimentary rocks. They used in the production and development of soft rock mining industry, especially used in coal mines, mines. In the municipal construction, often used in soft ground pipeline digging. And TBM application ability is widely can be basically any structure and section size of mining, regardless of roadway section has more complex can satisfy people's needs. Therefore, people have unanimously welcomed.In addition to the high flexibility and adaptability, boring machine also amaximum cost is low, good economy, general of roadheader have great power, but it is controlled by electromagnetic convenient. Therefore, compared with other machine, it can better dig into hard rock and crushed, such as continuous mining and mining.Today, in the science and technology rapid development, people design the roadheader performance and other aspects have made great progress, they have far more than the coal mining, the main change in recent 50 years. The machine weight and size than the previous increase a lot, cutting head power increased, the supporting rod, rake mechanism and control system have been greatly improved. High efficiency cutting head design, high cutting rate cut tooth development, high pressure water jet assisted cutting, electric hydraulic integration, the larger the place was the use of automatic control system and According to the different geological conditions of indirect control, so these all make the cutting capacity of the machine, work efficiency, power and so on have been greatly improved.中文译文掘进机在采矿和隧道中的应用掘进机为方便的挖掘硬岩而提供了一个独特的能力。

挖掘机臂液压系统的模型化参量估计摘要首先介绍了液压挖掘机的一个改装的电动液压的比例系统。

根据负载独立流量分配（LUDV ）系统的原则和特点，以动臂液压系统为例并忽略液压缸中的油大量泄漏，建立一个力平衡方程和一个液压缸的连续性方程。

基于电动液压的比例阀门的流体运动方程，测试的分析穿过阀门的压力的不同。

结果显示压力的差异并不会改变负载，此时负载接近2.0MPa。

然后假设穿过阀门的液压油与阀芯的位移成正比并且不受负载影响，提出了一个电液控制系统的简化模型。

同时通过分析结构和承重的动臂装置，并将机械臂的力矩等效方程与旋转法、参数估计估计法结合起来建立了液压缸以等质量等为参数的受力平衡参数方程。

最后用阶跃电流控制电液比例阀来测试动臂液压缸中液压油的阶跃响应。

根据实验曲线，阀门的流量增益系数被确定为2.825×10-4m3/(s·A)，并验证了该模型。

关键词：挖掘机，电液比例系统，负载独立流量分配（LUDV ）系统，建模，参数估计1 引言由于液压挖掘机具有高效率、多功能的优点，所以被广泛应用于矿山，道路建设，民事和军事建设，危险废物清理领域。

液压挖掘机在施工机械领域中也发挥了重要作用。

目前，机电一体化和自动化已成为施工机械发展的最新趋势。

因此，自动挖掘机在许多国家逐渐变得普遍并被认为重点。

挖掘机可以用许多控制方法自动地控制操作器。

每种使用方法，研究员必须知道操作器结构和液压机构的动态和静态特征。

即确切的数学模型有利于控制器的设计。

然而，来自外部的干扰使得机械结构模型和各种非线性液压制动器的时变参数很难确定。

关于挖掘机时滞控制的研究已经有人在研究了。

NGUYEN利用模糊的滑动方式和阻抗来控制挖掘机动臂的运动，SHAHRAM等采取了阻抗对挖掘机远距传物的控制。

液压机构非线性模型已经由研究员开发出来了。

然而，复杂和昂贵的设计控制器限制了它的应用。

在本文，根据提出的模型，根据工程学和受力平衡，挖掘机臂液压机构模型简化为连续均衡的液压缸和流动均衡的电液比例阀；同时，确定了模型的参量的估计方法和等式。

挖掘机英语1800字ExcavatorExcavator, also called digger, is an engineering vehicle consisting of a boom, bucket and cab on a rotating platform, also known as a house. The house sits atop an undercarriage with tracks or wheels. Excavators are used in various construction projects, such as digging trenches and foundations, demolition work, and mining.Types of ExcavatorThere are several types of excavator available, each designed for a specific type of job:1. Standard/Full-sized Excavator – This is the largest and most common type of excavator, typically weighing between 25-45 tonnes. These excavators are designed for heavy-duty excavation work and can be used for a wide range of tasks, including digging and levelling large areas.2. Mini Excavator – This excavator is smaller and more compact than a standard excavator, usually weighing between 1-8 tonnes. Mini excavators have a smaller bucket and are ideal for smaller-scale excavation work, such as gardening and landscaping.3. Long-Reach Excavator – This excavator has a longer boom and arm than a standard excavator, allowing it to reach further and excavate deeper.This type of excavator is useful for tasks such as dredging and deep excavation work.4. Wheeled Excavator – This is an excavator with wheels instead of tracks. It is useful for working on hard surfaces, such as pavement, and is ideal for urban areas where space is limited.Components of ExcavatorExcavators consist of several components that work together to excavate and move material:1. Boom – This is the long arm that extends from the cab and holds the bucket. The boom can be raised and lowered to reach different heights.2. Arm – This is the part of the excavator that extends from the boom and holds the bucket. The arm can also be raised and lowered to reach different depths.3. Bucket – This is the scoop-like attachment that is used to dig and move material. The bucket can be changed out for different sizes and shapes depending on the job.4. Cab – The cab is where the operator sits and controls the excavator. It contains the controls for the boom, arm, and bucket.5. Undercarriage – The undercarriage is the part of the excavator that supports the cab and rotates the house. It consists of tracks or wheels, depending on the type of excavator.Uses of ExcavatorExcavators have many uses, including:1. Digging trenches for utilities such as water, gas, and electricity.2. Clearing land for construction projects.3. Demolishing buildings and structures.4. Digging foundations for buildings.5. Moving and shaping dirt for landscaping projects.6. Mining operations.Safety ConsiderationsExcavators are powerful and dangerous machines that require skill and experience to operate safely. To minimize safety hazards, it is important to adhere to the following safety guidelines:1. Only trained and experienced operators should operate excavators.2. Excavators should be inspected before each use to ensure they are in good working order.3. All safety features, such as seat belts and roll bars, should be used.4. The area where the excavator will be used should be clear of any hazards or obstacles.5. Operators should communicate with other workers on the site to ensure safety.Excavators are versatile and powerful machines that have revolutionized the construction and excavation industries. With proper training and safety precautions, they can be a valuable tool for a variety of excavation and construction projects.。

附录现代工程机械行业的技术进步大型机械式挖掘机在目前国际国内在矿山开采及工程施工中有着广泛的应用，其性能的优劣对生产率有很大的影响.在国际市场竟争日趋激烈的今天，如何提高产品的质量是提高其市场竞争力的关键。

目前，我国的大型机械式挖掘机在设计水平，设计手段及产品质量上与国外同类产品相比尚有较大差距.国外已经将人一机一环境作为一个系统统一考虑，提倡低振动、低噪音的绿色设计，将现代设计方法(电子模拟理论、动态设计、可靠性设计等)普遍地应用于挖掘机设计，使产品设计现代化，性能可靠。

而我国仍然主要采用传统的仿型设计，而近年来才将现代设计方法逐步应用到挖掘机的设计上，但在这方面工作开展的不得力，主要表现在自行设计开发能力不够，基础工作做得不完善，尤其在挖掘机动力学方面。

挖掘机结构非常复杂，往往是多发动机同时驱动，同时工作环境恶劣，外载荷成随机性变化，因此在设计大型矿用挖掘机的新产品时，为了使其作业安全，工作顺畅，除必要的理论分析和静强度计算外，还必须要进行动力学分析和计算，以在设计之初保证机械的动强度和可靠性。

在进行这种分析时，土壤的力学特性必须考虑，而且是重要因素。

通过进行动力学研究，才能确定挖掘机各部件的载荷特性，设计出质量可靠的产品。

Modern construction machinery industry of technical progress Large-size mechanical mining excavator is used widely in international and domestic engineering construction and mining performance, and its property defines the efficiency much.Now because the international market is opened step step, how to promote the quality of excavator is the key that a factory reinforces its competing force.In our country，the designing elevation and production quality on excavator can not keep up with international advanced technology applying on excavator.Now the advanced technology has already applied advanced designing method on excavator designing，such as electronic simulating theory，dynamic design， reliability design and so on.But in our country ,the most excavator design has still applied the traditional design method ,the modern design method has not began to be actually applied .The prime display is that the capability of self-design is not enough and the basic work has not done perfectly especially the excavator kinetics .The construct of excavator is very complex and the multiple movers often work simultaneously.at the same time its working environment is very bad and the eternal load varies randomly.As a result ,when designing the new product of excavator ,in order to ensure the performance safety，the designer not only has the basic theory analysis on static load computing ,but also do necessary work about the kinetics of mechanism to qualify the dynamic reliability in the period of designing .Trough the kinetic analysis ,the load property of all the elements in excavator can be decided so as to design reliable product .。

美国控制会议程序宾夕法尼亚州费城，1998年6月液压挖掘机的高性能摆动速度跟踪控制姚斌+，乔扎恩+ +的，道格拉斯··克勒+ +，约翰·Litherland + ++机械工程学院普渡大学西拉斐特，IN 47907byao@+ +的进阶液压集团来，Caterpillar Inc在[6],通过考虑特定的非线性电液伺服系统模型的不确定性，姚明和T omizuka提出的自适应控制(电弧)的方法为高性能鲁棒控制的一个自由度电液提供一个严格的理论框架。

这个非线性相关的液压动力学(非线性函数描述的关系)仔细检查。

弧李雅普诺夫函数引起摩擦力的非线性液压动力学物理理论建立。

这使得摇摆运动控制充满挑战性;本文主要对高性能摆动速度跟踪控制的工业液压挖掘机进行研究。

一个工业液压挖掘机由一个主架,一个旋转结构，液压马达,和一个机器人的手臂构成。

该链接安装在旋转结构,由三个独立的液压缸提供必要的运动。

尽管各种不确定性，通过调节流量,斗杆遵循司机给出的摆动速度命令平稳地加速/减速,。

然而,开发一个高性能的摇摆运动控制器仍然存在一些困难。

首先,由于运动的联动和未知的有效载荷，摆动惯性是变化的和未知的。

这个未知惯性只能度量重力和非线性压力。

工业液压系统中任何一种闭环控制都有一种常见的问题如跳跃，处理的目的:一是推出优质的自适应控制器和其他红外非线性控制器产品，方法[6]可以处理。

第二,系统还有其他副例如swing扭矩。

第三,名义上的摇摆不应超过摆动马达，由于这些困难,挖掘机电流无法使用控制算法;相反,所有这些困难都可以开环练习和实践解决。

因此本文提供了两个高性能的设计，通过解决theorettime -不同和未知的摇摆构造简单、实用解决办法。

2问题公式化和动态模型对于这个ponents挖掘机初始的探讨;(二)ponents如阀门的关键部件，假设该设计流量。

该元件在下面给出。

2.1动态模型I挖掘机摆动qt）的＆= D M P。

中英文对照资料外文翻译文献英文文献Roadheader applications in mining and tunneling industries ABSTRACTRoadheaders offer a unique capability and flexibility for the excavation of soft to medium strength rock formations, therefore, are widely used in underground mining and tunneling operations. A critical issue in successful roadheader application is the ability to develop accurate and reliable estimates of machine production capacity and the associated bit costs. This paper presents and discusses the recent work completed at the Earth Mechanics Institute of Colorado School of Mines on the use of historical data for use as a performance predictor model. The model is based on extensive field data collected from different roadheader operations in a wide variety of geologic formations. The paper also discusses the development of this database and the resultant empirical performance prediction equations derived to estimate roadheader cutting rates and bit consumption.INTRODUCTIONThe more widespread use of the mechanical excavation systems is a trend set by increasing pressure on the mining and civil construction industries to move away from the conventional drill and blast methods to improve productivity and reduce costs. The additional benefits of mechanical mining include significantly improved safety, reduced ground support requirements and fewer personnel. These advantages coupled with recent enhancements in machine performance and reliability have resulted in mechanical miners taking a larger share of the rock excavation market.Roadheaders are the most widely used underground partial-face excavation machines for soft to medium strength rocks, particularly for sedimentary rocks. They are used for both development and production in soft rock mining industry (i.e. main haulage drifts, roadways, cross-cuts, etc.) particularly in coal, industrial minerals and evaporitic rocks. In civil construction, they findextensive use for excavation of tunnels (railway, roadway, sewer, diversion tunnels, etc.) in soft ground conditions, as well as for enlargement and rehabilitation of various underground structures. Their ability to excavate almost any profile opening also makes them very attractive to those mining and civil construction projects where various opening sizes and profiles need to be constructed.In addition to their high mobility and versatility, roadheaders are generally low capital cost systems compared to the most other mechanical excavators. Because of higher cutting power density due to a smaller cutting drum, they offer the capability to excavate rocks harder and more abrasive than their counterparts, such as the continuous miners and the borers. ROADHEADERS IN LAST 50 YEARSRoadheaders were first developed for mechanical excavation of coal in the early 50s. Today, their application areas have expanded beyond coal mining as a result of continual performance increases brought about by new technological developments and design improvements. The major improvements achieved in the last 50 years consist of steadily increased machine weight, size and cutterhead power, improved design of boom, muck pick up and loading system, more efficient cutterhead design, metallurgical developments in cutting bits, advances in hydraulic and electrical systems, and more widespread use of automation and remote control features. All these have led to drastic enhancements in machine cutting capabilities, system availability and the service life.Machine weights have reached up to 120 tons providing more stable and stiffer (less vibration, less maintenance) platforms from which higher thrust forces can be generated for attacking harder rock formations. . The cutterhead power has increased significantly, approaching 500 kW to allow for higher torque capacities. Modern machines have the ability to cutcross-sections over 100m2 from a stationary point. Computer aided cutterhead lacing design has developed to a stage to enable the design of optimal bit layout to achieve the maximum efficiency in the rock and geologic conditions to be encountered. The cutting bits have evolved from simple chisel to robust conical bits. The muck collection and transport systems have also undergone major improvements, increasing attainable production rates. The loading apron can now be manufactured as an extendible piece providing for more mobility and flexibility. The machines can be equipped with rock bolting and automatic dust suppression equipment to enhance the safetyof personnel working at the heading. They can also be fitted with laser-guided alignment control systems, computer profile controlling and remote control systems allowing for reduced operator sensitivity coupled with increased efficiency and productivity. Figure-1 shows a picture of a modern transverse type roadheader with telescopic boom and bolting system.Mobility, flexibility and the selective mining capability constitute some of the most important application advantages of roadheaders leading to cost effective operations. Mobility means easy relocation from one face to another to meet the daily development and production requirements of a mine. Flexibility allows for quick changes in operational conditions such asFigure-1: A Transverse Cutterhead Roadheader (Courtesy of Voest Alpine)different opening profiles (horse-shoe, rectangular, etc.), cross-sectional sizes, gradients (up to 20, sometimes 30 degrees), and the turning radius (can make an almost 90 degree turn). Selectivity refers to the ability to excavate different parts of a mixed face where the ore can be mined separately to reduce dilution and to minimize waste handling, both contributing to improved productivity. Since roadheaders are partial-face machines, the face is accessible, and therefore, cutters can be inspected and changed easily, and the roof support can be installed very close to the face. In addition to these, high production rates in favorable ground conditions, improved safety, reduced ground support and ventilation requirements, all resulting in reduced excavation costs are the other important advantages of roadheaders.The hard rock cutting ability of roadheaders is the most important limiting factor affecting their applications. This is mostly due to the high wear experienced by drag bits in hard, abrasiverocks. The present day, heavy-duty roadheaders can economically cut most rock formations up to 100 MPa (~14,500 psi) uniaxial compressive strength (UCS) and rocks up to 160 MPa (~23,000 psi) UCS if favorable jointing or bedding is present with low RQD numbers. Increasing frequency of joints or other rock weaknesses make the rock excavation easier as the machine simply pulls or rips out the blocks instead of cutting them. If the rock is very abrasive, or the pick consumption rate is more than 1-pick/m3, then roadheader excavation usually becomes uneconomical due to frequent bit changes coupled with increased machine vibrations and maintenance costs.A significant amount of effort has been placed over the years on increasing the ability of roadheaders to cut hard rock. Most of these efforts have focused on structural changes in the machines, such as increased weight, stiffer frames and more cutterhead power. Extensive field trials of these machines showed that the cutting tool is still the weakest point in hard rock excavation. Unless a drastic improvement is achieved in bit life, the true hard rock cutting is still beyond the realm of possibility with roadheaders. The Earth Mechanics Institute(EMI) of the Colorado School of Mines has been developing a new cutter technology, the Mini-Disc Cutter, to implement the hard rock cutting ability of disc cutters on roadheaders, as well as other types of mechanical excavators (Ozdemir et al, 1995). The full-scale laboratory tests with a standard transverse cutterhead showed that MiniDisc Cutters could increase the ability of the roadheaders for hard rock excavation while providing for lesser cutter change and maintenance stoppages. This new cutting technology holds great promise for application on roadheaders to extend their capability into economical excavation of hard rocks. In addition, using the mini-disc cutters, a drum miner concept has been developed by EMI for application to hard rock mine development. A picture of the drum miner during full-scale laboratory testing is shown in Figure-2.Figure-2: Drum Miner CutterheadFIELD PERFORMANCE DATABASEPerformance prediction is an important factor for successful roadheader application. This deals generally with machine selection, production rate and bit cost estimation. Successful application of roadheader technology to any mining operation dictates that accurate and reliable estimates are developed for attainable production rates and the accompanying bit costs. In addition, it is of crucial importance that the bit design and cutterhead layout is optimized for the rock conditions to be encountered during excavation.Performance prediction encompasses the assessment of instantaneous cutting rates, bit consumption rates and machine utilization for different geological units. The instantaneous cutting rate (ICR) is the production rate during actual cutting time, (tons or m3 / cutting hour). Pick consumption rate refers to the number of picks changed per unit volume or weight of rock excavated, (picks / m3 or ton). Machine utilization is the percentage of time used for excavation during the projectTable-I: Classification of the Information in the DatabaseThe Earth Mechanics Institute of the Colorado School of Mines jointly with the Mining Department of the Istanbul Technical University has established an extensive database related to the field performance of roadheaders with the objective of developing empirical models for accurate and reliable performance predictions. The database contains field data from numerous mining and civil construction projects worldwide and includes a variety of roadheaders and different geotechnical conditions.The empirical performance prediction methods are principally based on the past experience and the statistical interpretation of the previously recorded case histories. To obtain the required field data in an usable and meaningful format, a data collection sheet was prepared and sent to major contractors, owners, consultants, and roadheader manufacturers. In addition, data wasgathered from available literature on roadheader performance and through actual visits to job sites. This data collection effort is continuing.The database includes six categories of information, as shown in Table-I. The geological parameters in the database consist generally of rock mass and intact rock properties. The most important and pertinent rock mass properties contained in the database include Rock Quality Designation (RQD), bedding thickness, strike and dip of joint sets and hydrological conditions. The intact rock properties are uniaxial compressive strength, tensile strength, quartz content, texture and abrasivity. The rock formations are divided into separate zones to minimize the variations in the machine performance data to provide for more accurate analysis. This also simplifies the classification of the properties for each zone and the analysis of the field performance data.The major roadheader parameters included are the machine type (crawler mounted, shielded), machine weight, cutterhead type (axial, transverse), cutterhead power, cutterhead-lacing design, boom type (single, double, telescopic, articulated), and the ancillary equipment (i.e.grippers, automatic profiling, laser guidance, bit cooling and dust suppression by water jets, etc.).The operational parameters generally affect the performance of the excavator through machine utilization. The most important operational parameters include ground support, back up system (transportation, utility lines, power supply, surveying, etc.), ground treatment (water drainage, grouting, freezing, etc.), labor (availability and quality), and organization of the project (management, shift hours, material supply, etc.).CONCLUSIONSThe evaluation and analysis of the data compiled in the roadheader field performance database has successfully yielded a set of equations which can be used to predict the instantaneous cutting rate (ICR) and the bit consumption rate(BCR) for roadheaders. A good relationship was found to exist between these two parameters and the machine power (P), weight (W) and the rock compressive strength (UCS). Equations were developed for these parameters as a function of P, W and UCS. These equations were found mainly applicable to soft rocks of evaporatic origin. The current analysis is being extended to include harder rocks with or without joints to make the equations more universal. In jointed rock, the RQD value will be utilized as a measure of rockmass characteristics from a roadheader cuttability viewpoint. It is believed that these efforts will lead to the formulation of an accurate roadheader performance prediction model which can be used in different rock types where the roadheaders are economically applicable.中文译文掘进机在采矿和隧道业中的应用摘要掘进机为方便的挖掘硬岩而提供了一个独特的能力。

(文档含英文原文和中文翻译)中英文翻译外文文献A Summary of Small-size Excavators Home and Abroad I. The brief introduction of hydraulic excavatorParts such as the hydraulic excavator is by engine, hydraulic system and works device and walks device and electric control etc are formed. The hydraulic system is formed by hydraulic pump, control valve, hydraulic cylinder, hydraulic pressure motor, pipe route and fuel tank etc. The electric control system includes supervision dish, motor control system, pump brain and various kinds of sensor and solenoid valves etc. The hydraulic excavator is general by the work device and turns round the device and walks device three is mostly formed. According to his construction and use, we can differentiate : many kinds of typespressure, turns round entirely, not turns round entirely, utility version, mould for a special purpose, the joining with a hinge type and arm type stretched out and drawn back etc.The work device is directly accomplishing the device that excavates the assignment. It has been joined with a hinge by moves the arm, fights the pole and shovels the fill etc three parts. Moving that the arm rises and falls and the pole fought stretches out and draws back and shoveling fighting moves all with moving back and forth type two effect hydraulic cylinders control. In order to suit the needs of various difference construction school assignments, the hydraulic pressure excavator can be joined in marriage loading many kinds of work devices, if excavating and many kinds of school assignment machines and tools such as lifting job, loading, leveling, clamp and pushes soil and shock hammer etc.Turning round and walks the device is the organism of hydraulic pressure excavator, upper setting up power-on device and transmission system of turntable. The engine is the power supply of hydraulic pressure excavator, and adopts diesel oil will also can modify the electromotor in the convenient place mostly.The hydraulic drive system by way of the hydraulic pump with the engine the motive force transmission to hydraulic pressure motor and hydraulic cylinder etc actuator, the promotion work device moves, thus accomplishes the various school assignments. Take more PV-200's mould hydraulic pressure excavators of use in building site as the example. This machine adopts the type the opening center load of advanced version to be passed feeling system (OLSS). This system is with oblique of control type oblique the method of angle (export volume of flow ) variable plunger pump, and reduced the power delivery of engine, thus reduces the oil consumption burnt, and is one kind of saving energy mould system. The characteristic of this kind of hydraulic system is: the fixed torque is controlled, and it is unchangeable to keep the hydraulic pump drive torque, and year absolutely control can reduce the off-loading loss of school assignment time; Oil capacity is controlled, and the export volume of flow of hydraulic pump in the time of can reducing neutral gear and fine control reduces the power loss.The history of the first hand excavator was published up to now to have more than 130 years, and went through from the steam drive fill to turn round that the machinery turns round the developing the course step by step of the complete automatic hydraulic pressure excavator of excavator and application mechanical and electrical liquid integration technology to power drive and the internal-combustion engine drive in the time. Thehydraulic pressure to anti- the type hanging which shoveled machinery in the 1940’s, and developing out the pulling type at the initial stage of in the 1950’s with middle period in succession, to turn round the full hydraulic pressure of hydraulic pressure excavator and caterpillar tread type entirely mechanical. Initial stage the trial hydraulic pressure excavator is the hydraulic technique that adopts plane and machine tool, lacking the hydraulic pressure component that is suitable in the mechanical various operating modes, it is stable inadequately to make the quality, and necessary is not completely yet. From in the 1960’s, the hydraulic pressure excavator is entered the popularization and in vigorous development stage, and mechanical manufacturing plant and the breed of each country increases very fast, and the output is rapidly increased. 83% of the mechanical gross output was occupied to hydraulic pressure excavator output, and is close to 100% at present 1968-1970 certain period.ⅡSmall excavator development and its tendency20th century 80 ~ 90's small mechanical device in construction and soon in municipal engineering, transportation, pipeline has displayed abigger superiority and can rapidly develop. The small excavator forsaved the manpower, the physical resource in these projects makes thesmall excavator mainly to use in the city the constructionconstruction and generally left a bigger contribution,gradually became in the city construct ionto have the representative construction machinery.The small excavator development mainly relies on the urbanconstruction development, because city transformation, constructionconstruction more, the request construction time short, theconstruction machinery affects small, safe, the low pollution, theradius of gyration to the environment is small, is advantageous fortransports as well as has with the city scenery appearancecoordination outward appearance, the small excavator has satisfied thecity each kind of work request, can maximum limit display itsproductivity in the city narrow working space, therefore has theunique superiority.1. The development of small excavatorsThe small excavator mainly uses in the city the constructionconstruction and the general housing repairs and maintains and so onthe work, the request has the good operating performance and therotation performance.Initial small excavator by tire type primarily, because the tire typewalks the natural in the soft ground and the passing difference,afterwards gradually by the marching substitution, and in moved thearm strut organization place toorganism tocarry on swings, completed the trench sidewall excavation renovationwork behind, but this kind of small excavator excavation scope wassmall, cannot realize the material. Hereafter, the small excavator increased upside has rotated theorganization, has solved behind themetial and so on the problem, enhancedthe excavator operating performance, formed the small excavator thebasic structure. Afterwards, the small excavator in the radius ofgyration, behind the field of vision, moved aspect and so on armelevation angle, machine capability has the further improvement,develops for the present standard type.2.Technical progressesSmall excavator working conditions majority of in city, in order toprevent walks when damages the road surface, starts from the 80's touse the rubber caterpillar band, and gradually obtains thepopularization. A rubber caterpillar band heavy wheel is when theinternal iron circuit board the movement, the hard circuit board jointplace and the heavy wheel contact falls to the ground, becomes walksthe destruction road surface main reason. Before uses the width shapeiron circuit board, a rubber caterpillar band heavy wheel diameter isbigger, therefore when approaches the ground, this slit changes in abig way, creates the caterpillar band to the road surface destruction.The super small excavator use and the before same heavy wheel, onlywas the hard circuit board which in the caterpillar band used changesnarrowly, therefore when contacted the ground the slit changesslightly, reduced to the damage of ground.Rear area the small rotation excavator rotation rear part size isextremely small, in order to guarantee the excavator work thestability, must have the enough counterweight, and in does notincrease the mechanical weight under the premise, uses increases thecaterpillar band length and widens the chassis and so on the effectivemethod.But, the chassis width is transported the truck width the limit, forsolves this problem, has used ViCTAS in the super small excavator (Vio- Crawler Technology by Advanced Stability) the technology.fortablenessThe small excavator majority of seals cab, has not rained when thechair frequently drips wet by the rain seeps. In order to solve thisproblem, the use surface and the interior gather a peaceful fat rubberbody to manufacture has not sewn the seam the chair, cannot againfrom sew the seam place destruction, the durability also can enhance,becomes the complete waterproofing chair.Impels the small excavator market fast development the factor:mobile is flexible, extremely is suitable for work andso on cities each kind of pipelining, foundation construction, publicutilities as well as house service. The small excavator compactvolume, the special design enable its to carry on the work in theenvironment which the large-scale excavator is unable to construct.(2) The small excavator has the multi-purpose small excavator truemerit is it has multi-purpose. The small excavator can install manyauxiliary works machines and tools, like the installment brokenhammer, the hydraulic pressure pliers use in the lightweightdemolision work, installs a clamp to use in to eliminate the work,installs the drum, the plate uses in the trench to fill in buriesthe compaction, the installment turns on lathe digs drills uses in thedrill hole, the lift hook uses in to hoist up heavy item and so on.(3)The small excavator is advantageous for the transportation and oneof shift work location small hydraulic pressure excavator market rapidexpansion reasons should belong to its size and the weight. The smallexcavation function conveniently shifts in each job location, thesmall excavator does not need the large-scale trailer perhaps theheavy-duty truck carries on the transportation, the small transportmeans may deliver. Like this not only can facilitate thetransportation, but also may greatly reduce the machine the cartageexpense.(4) Small excavator bright work characteristic: The rear part radiusof turn for the zero design, causes the small excavator not to need inthe work space limited environment mean industry time excavatoroperator to consider the job location is, whether thus enable theoperator to have the obstacle to hinder the excavator the rotation tosuffice wholly absorbed to the scoop operation, this has alsoprevented around the job location the building as well as theexcavator own damage.(5) Invests the repayment rate to be high, the cost recycles quicklyThe small excavator price is cheap, the cost recycles quickly.Slightly digs take the 6t level as the example, American, the Europeandate brand machine price about 400,000 Yuan, South Korea's machineprice about 320,000 Yuan, the domestically produced machine price is30 ~ 320,000 Yuan some brands is lower; But the 20t level center digsthe price in 70 ~ 1 million Yuan. The higher investment repayment ratecauses the small excavator deeply the general center small earthworkconstruction to contract owner's welcome.4 Small excavators technological development tendenciesThe small excavator technological development complied with the globaldiversification job location the demand, has experienced more than 30years history successional variationtechnicalperformance, job function, work efficiency, security, environmentalprotection, energy conservation and maintenance maintenance had thelarge scale enhancement, has formed the quite consistent technicalstandard and the work standard. Mainly manifests in following severalaspects:(1) The tailless rotation and moves the arm deflection technology totake slightly digs the basic concept to move the arm deflection andthe tailless rotation function later period promotes in the 1990s facethe world market. Moves the arm deflection in the organism front part,but does not have the organization to be able to realize is locatednearby the lower part of wall the direct excavation work to havefrequently to move the fuselage. The tailless rotation structureapplication, causes it when the neck of land work does not need toworry the rear part the collision. The tailless rotation structuraldesign difficulty lies in rotates in the platform the generalarrangement, the dynamic system thermal equilibrium solution as wellas the entire machine stable solution. But moves the arm deflectionorganization the design difficulty to lie in an articulation positionthe determination and the hinge body manufacture technology.(2) New hydraulic control technologyThe new hydraulic control technology should have the work efficiencyhigh, the serviceability is good, has the good efficiency, may carryon the high efficiency, the powerful work. The new fluid environmentcompatibility presses the system not to shoulder the size theinfluence, completely needs the oil of the hydraulic pressure system, the current capacity accordingto the control handle scope distribution point, definitely may deferto operator's intention with ease to complete the work. At the sametime, because the engine load is small may avoid the current capacitythe senseless loss, can realize slightly moves the operation and thecompound operation. The new hydraulic control technology applicationalso can increase the dynamic output, enhances the work speed, reducesthe fuel consumption.(3)Security performanceHas the strict legal rule in the European market and the North Americamarket to the security, the equipment security performance can givethe operator to provide the relieved work the environment, enhancesoperator's security. The small excavator security performance mainlymanifests in the cab ROPS/FOPS design below, should satisfy theperformance requirement in the cab experiment:①May satisfy must energy absorption;② May satisfy must anti- load;(4) Environmental protection technologyMainly manifests in the power, the low oil consumption, cleanlydischarges the engine in the application. The new engine shouldsatisfy the American EPATier2 standard and the European EU standard,will cause the environmental pollution the compound to discharge thecontrol in the threshold. The new engine simultaneously reduced thevibration and the noise, is beneficial to the environmental protectionand operator's health.(5) Man-machine project technologyThe cab conforms to the man-machine engineering principle,internal spacious, field of vision open, modelling artistic, the easeof operation, reduces effort the measuring appliance demonstrationdirect-viewing, is accurate, can provide one kind of comfortableoperating environment to the pilot, fully reduces pilot's weariness.(6) Services the maintenance technologyMaintains from the current maintenance to the regular inspectionservice, the simplification operation is extremely essential, canenhance the machine the reliability, makes the machine throughout tomaintain the good condition. Must cause the daily inspection side, the realization not to need withthe aid of the tool as soon as to touch the type operation.Maintenance repair then quickly dnd simplely, but fast carries on theinternal spare part and the system inspection and the service. Moreover, in the design must fully consider prevents the machine theaccident damage.Such as the cowling, the guard plateguards against the collision structural design;Moves the arm hydraulic cylinder guard plate design; Fuel oil tank draw-offvalve; The independence bulldozes the board hydraulic pressure hosedesign; Waterproofing electric system design; In the work installmenthose sets at the design; X frame and halfway up the mountainsidecaterpillar band design; The engine machine oil filter elementreplacement time lengthens; Has forerunner system which the pipelinefilters; Dual spatially filters structure design and so on.5 ConclusionsSociety's development has a more tremendous influence to the smallexcavator, at present the overseas small excavator had the suitable development, like Carter other forces, company and so on Hitachi,small pine, Mitsubishi, the small excavator product has formed theseries, and in unceasingly carries on the development, the expandeduse, the increase appendix type. The domestic small excavatordevelopment has also obtained the certain result,中文译文国内外小型挖掘机发展综述一、液压挖掘机简介液压挖掘机是由发动机、液压系统、工作装置、行走装置和电气控制等部分组成。

英文文献Roadheader applications in mining and tunneling industriesH. Copur1, L. Ozdemir2, and J. Rostami31Graduate Student, 2 Director and Professor, and 3 Assistant ProfessorEarth Mechanics Institute, Colorado School of Mines, Golden, Colorado, 80401 ABSTRACTRoadheaders offer a unique capability and flexibility for the excavation of soft to medium strength rock formations, therefore, are widely used in underground mining and tunneling operations. A critical issue in successful roadheader application is the ability to develop accurate and reliable estimates of machine production capacity and the associated bit costs. This paper presents and discusses the recent work completed at the Earth Mechanics Institute of Colorado School of Mines on the use of historical data for use as a performance predictor model. The model is based on extensive field data collected from different roadheader operations in a wide variety of geologic formations. The paper also discusses the development of this database and the resultant empirical performance prediction equations derived to estimate roadheader cutting rates and bit consumption.INTRODUCTIONThe more widespread use of the mechanical excavation systems is a trend set by increasing pressure on the mining and civil construction industries to move away from the conventional drill and blast methods to improve productivity and reduce costs. The additional benefits of mechanical mining include significantly improved safety, reduced ground support requirements and fewer personnel. These advantages coupled with recent enhancements in machine performance and reliability have resulted in mechanical miners taking a larger share of the rock excavation market.Roadheaders are the most widely used underground partial-face excavation machines for soft to medium strength rocks, particularly for sedimentary rocks. They are used for both development and production in soft rock mining industry (i.e. main haulage drifts, roadways, cross-cuts, etc.) particularly in coal, industrial minerals and evaporitic rocks. In civil construction, they findextensive use for excavation of tunnels (railway, roadway, sewer, diversion tunnels, etc.) in soft ground conditions, as well as for enlargement and rehabilitation of various underground structures. Their ability to excavate almost any profile opening also makes them very attractive to those mining and civil construction projects where various opening sizes and profiles need to be constructed.In addition to their high mobility and versatility, roadheaders are generally low capital cost systems compared to the most other mechanical excavators. Because of higher cutting power density due to a smaller cutting drum, they offer the capability to excavate rocks harder and more abrasive than their counterparts, such as the continuous miners and the borers. ROADHEADERS IN LAST 50 YEARSRoadheaders were first developed for mechanical excavation of coal in the early 50s. Today, their application areas have expanded beyond coal mining as a result of continual performance increases brought about by new technological developments and design improvements. The major improvements achieved in the last 50 years consist of steadily increased machine weight, size and cutterhead power, improved design of boom, muck pick up and loading system, more efficient cutterhead design, metallurgical developments in cutting bits, advances in hydraulic and electrical systems, and more widespread use of automation and remote control features. All these have led to drastic enhancements in machine cutting capabilities, system availability and the service life.Machine weights have reached up to 120 tons providing more stable and stiffer (less vibration, less maintenance) platforms from which higher thrust forces can be generated for attacking harder rock formations. . The cutterhead power has increased significantly, approaching 500 kW to allow for higher torque capacities. Modern machines have the ability to cutcross-sections over 100m2 from a stationary point. Computer aided cutterhead lacing design has developed to a stage to enable the design of optimal bit layout to achieve the maximum efficiency in the rock and geologic conditions to be encountered. The cutting bits have evolved from simple chisel to robust conical bits. The muck collection and transport systems have also undergone major improvements, increasing attainable production rates. The loading apron can now be manufactured as an extendible piece providing for more mobility and flexibility. The machines can be equipped with rock bolting and automatic dust suppression equipment to enhance the safetyof personnel working at the heading. They can also be fitted with laser-guided alignment control systems, computer profile controlling and remote control systems allowing for reduced operator sensitivity coupled with increased efficiency and productivity. Figure-1 shows a picture of a modern transverse type roadheader with telescopic boom and bolting system.Mobility, flexibility and the selective mining capability constitute some of the most important application advantages of roadheaders leading to cost effective operations. Mobility means easy relocation from one face to another to meet the daily development and production requirements of a mine. Flexibility allows for quick changes in operational conditions such asFigure-1: A Transverse Cutterhead Roadheader (Courtesy of Voest Alpine)different opening profiles (horse-shoe, rectangular, etc.), cross-sectional sizes, gradients (up to 20, sometimes 30 degrees), and the turning radius (can make an almost 90 degree turn). Selectivity refers to the ability to excavate different parts of a mixed face where the ore can be mined separately to reduce dilution and to minimize waste handling, both contributing to improved productivity. Since roadheaders are partial-face machines, the face is accessible, and therefore, cutters can be inspected and changed easily, and the roof support can be installed very close to the face. In addition to these, high production rates in favorable ground conditions, improved safety, reduced ground support and ventilation requirements, all resulting in reduced excavation costs are the other important advantages of roadheaders.The hard rock cutting ability of roadheaders is the most important limiting factor affecting their applications. This is mostly due to the high wear experienced by drag bits in hard, abrasiverocks. The present day, heavy-duty roadheaders can economically cut most rock formations up to 100 MPa (~14,500 psi) uniaxial compressive strength (UCS) and rocks up to 160 MPa (~23,000 psi) UCS if favorable jointing or bedding is present with low RQD numbers. Increasing frequency of joints or other rock weaknesses make the rock excavation easier as the machine simply pulls or rips out the blocks instead of cutting them. If the rock is very abrasive, or the pick consumption rate is more than 1-pick/m3, then roadheader excavation usually becomes uneconomical due to frequent bit changes coupled with increased machine vibrations and maintenance costs.A significant amount of effort has been placed over the years on increasing the ability of roadheaders to cut hard rock. Most of these efforts have focused on structural changes in the machines, such as increased weight, stiffer frames and more cutterhead power. Extensive field trials of these machines showed that the cutting tool is still the weakest point in hard rock excavation. Unless a drastic improvement is achieved in bit life, the true hard rock cutting is still beyond the realm of possibility with roadheaders. The Earth Mechanics Institute(EMI) of the Colorado School of Mines has been developing a new cutter technology, the Mini-Disc Cutter, to implement the hard rock cutting ability of disc cutters on roadheaders, as well as other types of mechanical excavators (Ozdemir et al, 1995). The full-scale laboratory tests with a standard transverse cutterhead showed that MiniDisc Cutters could increase the ability of the roadheaders for hard rock excavation while providing for lesser cutter change and maintenance stoppages. This new cutting technology holds great promise for application on roadheaders to extend their capability into economical excavation of hard rocks. In addition, using the mini-disc cutters, a drum miner concept has been developed by EMI for application to hard rock mine development. A picture of the drum miner during full-scale laboratory testing is shown in Figure-2.Figure-2: Drum Miner CutterheadFIELD PERFORMANCE DATABASEPerformance prediction is an important factor for successful roadheader application. This deals generally with machine selection, production rate and bit cost estimation. Successful application of roadheader technology to any mining operation dictates that accurate and reliable estimates are developed for attainable production rates and the accompanying bit costs. In addition, it is of crucial importance that the bit design and cutterhead layout is optimized for the rock conditions to be encountered during excavation.Performance prediction encompasses the assessment of instantaneous cutting rates, bit consumption rates and machine utilization for different geological units. The instantaneous cutting rate (ICR) is the production rate during actual cutting time, (tons or m3 / cutting hour). Pick consumption rate refers to the number of picks changed per unit volume or weight of rock excavated, (picks / m3 or ton). Machine utilization is the percentage of time used for excavation during the projectTable-I: Classification of the Information in the DatabaseThe Earth Mechanics Institute of the Colorado School of Mines jointly with the Mining Department of the Istanbul Technical University has established an extensive database related to the field performance of roadheaders with the objective of developing empirical models for accurate and reliable performance predictions. The database contains field data from numerous mining and civil construction projects worldwide and includes a variety of roadheaders and different geotechnical conditions.The empirical performance prediction methods are principally based on the past experience and the statistical interpretation of the previously recorded case histories. To obtain the required field data in an usable and meaningful format, a data collection sheet was prepared and sent to major contractors, owners, consultants, and roadheader manufacturers. In addition, data wasgathered from available literature on roadheader performance and through actual visits to job sites. This data collection effort is continuing.The database includes six categories of information, as shown in Table-I. The geological parameters in the database consist generally of rock mass and intact rock properties. The most important and pertinent rock mass properties contained in the database include Rock Quality Designation (RQD), bedding thickness, strike and dip of joint sets and hydrological conditions. The intact rock properties are uniaxial compressive strength, tensile strength, quartz content, texture and abrasivity. The rock formations are divided into separate zones to minimize the variations in the machine performance data to provide for more accurate analysis. This also simplifies the classification of the properties for each zone and the analysis of the field performance data.The major roadheader parameters included are the machine type (crawler mounted, shielded), machine weight, cutterhead type (axial, transverse), cutterhead power, cutterhead-lacing design, boom type (single, double, telescopic, articulated), and the ancillary equipment (i.e.grippers, automatic profiling, laser guidance, bit cooling and dust suppression by water jets, etc.).The operational parameters generally affect the performance of the excavator through machine utilization. The most important operational parameters include ground support, back up system (transportation, utility lines, power supply, surveying, etc.), ground treatment (water drainage, grouting, freezing, etc.), labor (availability and quality), and organization of the project (management, shift hours, material supply, etc.).CONCLUSIONSThe evaluation and analysis of the data compiled in the roadheader field performance database has successfully yielded a set of equations which can be used to predict the instantaneous cutting rate (ICR) and the bit consumption rate(BCR) for roadheaders. A good relationship was found to exist between these two parameters and the machine power (P), weight (W) and the rock compressive strength (UCS). Equations were developed for these parameters as a function of P, W and UCS. These equations were found mainly applicable to soft rocks of evaporatic origin. The current analysis is being extended to include harder rocks with or without joints to make the equations more universal. In jointed rock, the RQD value will be utilized as a measure of rockmass characteristics from a roadheader cuttability viewpoint. It is believed that these efforts will lead to the formulation of an accurate roadheader performance prediction model which can be used in different rock types where the roadheaders are economically applicable.中文译文掘进机在采矿和隧道业中的应用摘要掘进机为方便的挖掘硬岩而提供了一个独特的能力。

介绍的挖掘机作文英语Title: Introduction to Excavator。

An excavator, also known as a digger, is a heavy construction equipment used primarily for digging trenches, holes, and foundations. It is equipped with a boom, a dipper or stick, a bucket, and a cab mounted on a rotating platform known as the house. Excavators are commonly usedin construction, mining, forestry, demolition, and other earthmoving applications due to their versatility and efficiency.The main components of an excavator include the following:1. Boom: The boom is the long arm of the excavator that extends from the house. It provides the excavator with horizontal reach and height for digging and lifting operations.2. Dipper or Stick: The dipper, also known as the stick, is attached to the end of the boom and holds the bucket. It controls the depth and angle of the bucket during digging operations.3. Bucket: The bucket is the attachment at the end of the dipper that is used for digging, scooping, and loading materials. Buckets come in various sizes and configurations depending on the specific application.4. House: The house is the upper structure of the excavator that houses the operator's cab, engine, hydraulic system, and other components. It can rotate 360 degrees, allowing the operator to work in any direction without repositioning the entire machine.5. Tracks or Wheels: Excavators can have either tracksor wheels for movement. Tracks provide better traction and stability on uneven terrain, while wheeled excavators offer greater mobility on smooth surfaces.Excavators are powered by diesel engines, which drivehydraulic pumps to control the movement of the boom, dipper, bucket, and house. The hydraulic system allows for precise and efficient operation, enabling the operator to perform a wide range of tasks with ease.In addition to digging, excavators can be equipped with various attachments to perform other functions such as:Grapple: Used for grabbing and lifting objects such as logs, rocks, and debris.Auger: Used for drilling holes in the ground for foundations, fence posts, and other purposes.Compactor: Used for compacting soil, gravel, and other materials to create a stable foundation.Breaker: Used for breaking up concrete, asphalt, and other hard surfaces during demolition or construction.Excavators come in a range of sizes, from compact mini-excavators weighing a few thousand pounds to largehydraulic excavators weighing several tons. The choice of excavator depends on the specific requirements of the job, including the type of terrain, the depth of excavation, and the size of the materials being handled.In conclusion, excavators are versatile and powerful machines that play a vital role in construction and earthmoving projects. With their ability to perform a wide range of tasks efficiently, they have become indispensable tools for contractors and construction companies worldwide. Whether digging trenches, demolishing buildings, or loading trucks, excavators continue to be at the forefront of modern construction technology.。

外文原文：The vertical Boom-type Roadheader design1 IntroductionMechanical design is in the process of product design and an important part of the main links, it is followed in programme design after the design work. The vertical Boom-type roadheader (the roadheader) to the overall design of the merits of complete machine play a decisive role, and the decision of the assembly, the system, coordination between the various components of the unity and match, to obtain the high-end performance and overall better economic efficiency technology. Roadheader design, including the following: 1)According to design project description choice type and various cellular construction pattern 2) Decides the complete machine the main technical performance parameter, Including size parameter, heavy parameter, the parameter of movement and the technical economy refer parameter, 3) According to system design performance requirement, definite complete machine system composition and between them match as well as each part main technical senate parameter, 4) The necessary whole, and the mapping of transmission, hydraulic, electronic control systems, and other plans.2 the selected models and various components and structural type, drive, and the overall layout of the reasonableIn determining the content, first task should be designed to meet the contents, especially the users of the main demands of the investigation, the two sides exchanged views repeatedly, to satisfy both users (or superior) conditions, can better meet the product development of the overall plan.2.1 the selected modelsAccording to roadheader use, for the coal mine tunnel boring or used for other sectors of the works, roadheader working conditions for cutting coal roadway or semi-Coal Lane, the compressive strength of coal and rock one-way (or the value of platts coefficient f) and the rock abrasion factor. At the same time the control line should be superscript MT138 ~ 1995"cantilevered Roadheader types and parameters",according to cutting coal and rock the biggest one-way compressive strength, the type of selected models.2.2 the structure of the various components, the way the driver identifiedRoadheader by cutting general agencies, shipping agencies, walking, hydraulic system, electronic control systems and auxiliary devices (such as dust removal devices, security devices, remote monitoring devices) and other components. 1) Cutting agencies. Cutting the drive from AC motor-driven, in the transmission system located in the general profile coupling with no mechanical overload protection device, the two planets reducer driven spindle front of the cutting head. Some sections of the working bodies boring machine has cut chain, disc-milling and cutting-such as cantilever. Cantilever due to the cutting-boring machine body flexible, relatively small, can cut a variety of shapes and sections of the roadway, and to achieve selective cutting, but cutting good effect, a higher rate of boring, so now used mainly cantilever Cutting-and has become boring machine working body of a basic pattern. By cutting head of the layout, is divided into horizontal and vertical axis of the two. The line-cutting head of the advantages are: Transmission convenient, compact and can be cut to any shape of the profile, easy access to the formation of a cross-section and is conducive to expansion in the use of cantilever, or ditch digging, in Waterloo. Cutting head the shape of a cylindrical, cone and the cone and cylindrical, as the latter two cutting head to drilling, and the cutting surface than the formation, use it more. This is the work of the shortcomings: As the longitudinal axis of cutting head in the horizontal swing at the cutting reaction force is not passed machine centres, with cantilevered form of torque to boring machine have a greater vibration, stability is poor. Therefore, the coal roadway excavation, the need to increase the body weight or support the installation of auxiliary equipment. At present, such a boring machine in some sections of the use of more boring machine. 2) Shipment of bodies. It generally from the middle loading and conveyor components. They were driven or focus may be linked, either by AC motor drive, can also be usedhydraulic motor drive. Trailing claw-is to use a turn moves the rake claws to continue to rake materials and in a reprint from transport operators. This structure is simple, reliable, small formfactor, loading good effect, the application is widespread. However, such institutions loading width restricted (because boring machine running track when agencies generally do not arouse). To expand the loading width, will shovel the entire harrow board, together with the claw agencies in the level of swing, or design dual rake claws, to expand the scope of loading. Institutions than the rake-wheel-claw simple, high intensity, reliable, but with less bulk materials. Loading agency programme is not only the installation of the claw-rake-wheel can also be installed, the two can be used interchangeably. Usually, the choice rake claw-loaded, but considering loading width of the problem, may choose to double rake claws, can also be designed to rake claw-round interchangeable with the loading mechanism. Some sections boring machine use of scraper chain conveyor agencies. Transportation agencies are generally undertaken by the tail to the nose tilted upward direction of the layout. Transportation agencies can be the driver, is about to motor or hydraulic motor and reducer layout in the scraper conveyor and around the side of the fuselage, the body in the driver loading at the same time, indirectly, to transport bodies to take the initiative to the tail shaft driven scraper Transportation agencies. This drive system components in small, relatively simple bodies, but loading and transportation agencies involved in the two campaigns, mutual influence. As the location less space layout more difficult. Transmission organizations to adopt an independent driver, is about to motor or hydraulic motor layout away from the machine side, driven by slow delivery agencies. This mode of transmission drive layout simple, and filling the campaign Hubuyingxiang. However, due to transmission and more dynamic components, the point of failure has increased. At present, the two transportation agencies are used, as appropriate, the design should be identified. General loading and institutions often use the same drive. Loading agencies can use motor-driven, can also be used hydraulic motor drive. However, in consideration of the working environment and wet with mud, optionalhydraulic motor drive for good. 3) Run institutions. Walking agencies tracked the general pattern, crawler-run institutions apply to the floor is uneven or soft conditions, no road track laying. Traction with large capacity, good mobility, reliability, flexibility and mobility on the floor adaptability of the advantages of good. But its complex structure, componentsand wear more serious. At present cross-section of the boring machine is usually used crawler-run institutions. Walking agencies tracked the general pattern, the two tracked separately by the respective power to drive, to achieve in situ. Caterpillar is the driving force of two motors and hydraulic motors, motor driver is generally set up a walking speed, hydraulic motor-driven large low-speed torque motor can be driven directly tracked sprocket, or used in the hydraulic motor speed Reducer led the drive sprocket track, it can achieve Promise governor. Tracked structure of a sliding and rolling two, when the speed machine to mobilize ≤ 10 m / min in the light Roadheader, should adopt the structure of sliding when the mobilization of speed machines> 10 m / min of heavy, severe Roadheader should be used Rolling structural type. 4) The hydraulic system. Hydraulic systems use of open-way valve system more centralized control (direct or remote control manipulation) way. Domestic and foreign use of the past, gear pumps, hydraulic system in recent years Roadheader used piston pump have increased the trend. 5) Electronic control system. Electronic control systems, including some power, control and inspection of the part. Electronic control system must be in accordance with the requirements of coal mine explosion-proof design, manufacture, testing, GB3836-2000 must meet the standards of the relevant provisions and requirements. In order to improve operations at the Roadheader in the security, operational flexibility and mechanical transmission part of the fault diagnosis and monitoring functions, from the practical point of view, the installation of the necessary machines from a remote control device, monitoring pressure, temperature, level and key parts the fault diagnosis device.2.3 LayoutGeneral layout of the contents include the following: 1) Identify thecomponents in complete machine said the location, shape and size of the request; 2) To identify the parts, components and the connections between complete machine; 3) estimates complete machine weight and the weight of all components requested; 4) layout of the manipulation of institutions, the driver's seat;5) examination of moving parts of the movement space, rule out the possibility of interference in the campaign.2.4 specific requirementsBoring machine in the general layout, the need to pay attention to the following questions: 1) institutions into the reducer reducer, as far as possible to coax axis; 2) cantilever and spade-suited to the size of relations, not only conducive to loading, to avoid cutting the first shovel cutting board; 3) the level of cantilever and vertical position can swing the center coincidence, can not overlap. From the increased stability of the machine, these are highly swing should be reduced. In the cantilever is not guaranteed to interfere with other agencies under the conditions of swing centres are located should try to rely on, but must ensure that the machines in the centre plane of vertical symmetry;4) When all the major components designed after. Checking should be carried out, does not meet requirements to be adjusted just so that the focus in track and less than the former center Shaopian L / 6 (L grounding for the track length). In addition, the center of gravity position in the demand for cutting bodies turret after the centerline, and Yuediyuehao high center of gravity to enhance stability when operating machinery. 5) the overall layout should consider the weight of symmetrical left and right and take care of work habits and to facilitate the operation. General driver in the left side of the fuselage and the fuselage in the rear, driver seat height should ensure that the people's attention, what good control of their machines, cutting out the rules of the roadway; 6) Caozong Tai position should be appropriate, should ensure that drivers easy manipulation, and effort. Instruments showed that the location devices for drivers to observe, not scattered normal operation of the driver's attention.2.5 types and power transmission components choicetransmission patterns and components should follow the principle of choice 1) the advanced nature of technology: machines to improve performance, increase productivity; 2) economic rationality: drive system as simple as possible, fewer components and easy processing, low price, easy maintenance, long life;3) reliability of the work: the transmission system reliability performance for the life of components, as well as component quality requirements; 4) adaptation: the drive system components should be adapted to load, working conditions and environmental conditions of the request. Agencies to the transmission system requirements and the choice of transmission patterns . Boring machine cutting, loading, transport, walking and other institutions generally are respectively transmission, all parts of the state and subject to different working conditions, thus driving patterns have different requirements. 1) institutions require a greater short-term Guozainengli, motor oil is very sensitive to the impact load, the loading capacity of low-impact cutting head for normal functioning. Therefore, the boring machine working body should adopt the motor-driven mechanical transmission type. Should make use of small size, power, a strong capacity for electric motors, and equipped with reliable electrical protection device. According to the compact body of work features, usually work in the reducer cantilever, an integral part of a cantilever. Cutting the first governor general way with a round peg for the method of transmission organizations to simple. 2) rake with institutions transmission device is characterized by: reducer be installed in the limited size of the lower part of the shovel plate, thus design a smaller space, poor working conditions. Reducer often soaked in muddy coal and rock in the cards when the material easy to overload. Trailing equipment, transportation agencies the use of mechanical transmission, for the larger motor, not the end of the conveyor installation, the shovel is generally installed on both sides of the board two motor, with a rake, a common power transmission organizations, such bound to make the Slowdown me the size of the increase in the spade under the board layout more tense. In addition, consider the claw and rake boards linked linked overload situation, to protect the motor did not burn, thegeneral needs of internal security in reducer friction-clutch. Trailing equipment, transportation agencies the use of motor oil transmission gear, as small size, light weight, will enable the two separate drive, thus simplifying transmission device, for the spade under the board layout, designed for good results sealed mechanical seal or reducer And shovel plate separation, while achieving automatic overload protection.3) walk the track-driven approach and a motor-driven motor oil in two ways. Respectively, through mechanical devices or directly from the slowdown in motor oil led the initiative sprocket running track. Mechanical transmission of the walking track, with General Motors will be tracked in two reducer rear, the brake hydraulic braking by mechanical means way. This transmission mode drive high reliability and low prices of motor, easy maintenance, but not speed, slow me larger, Lin Shui major roadway, the motor easily exposed to moisture and burned. Tracked walk to adopt hydraulic transmission patterns, simple system, better performance and advanced technology. Hydraulic transmission of the walking mechanism, in the form choice and hydraulic motor speed control mode design, there are different options. The use of low-speed torque motor-driven, characterized by the system simple, small size, light weight, to achieve stepless speed regulation and automatic overload protection. However, hydraulic motor drive complex, the high cost of manufacturing, maintenance more difficult. Gear used motor oil, the volume of high efficiency, performance and impact-resistant, easy maintenance, low cost, a 10 KW around the motor gear oil prices only with the power of the radial-Sema Da 1 / 10; small size, light weight. A 10 KW gear around the weight of motor oil, with the only major power low-speed torque motor of 1 / 18, the weight of the motor 1 / 13. Gear used motor oil, although lower-speed reducer size large torque motor, but a small electric (MRH-S50-13-type plane reducer transmission ratio i = 328). So can easily be motors, reducers, hydraulic Zhidong Fa, tight chain devices installed in the middle-tracked. In this way than on the technical performance of mechanical transmission, the economic indicators better than the low-speed torque motor drive. So has a unique advantage. The walking speed in two ways: one is a variable pump. The other is the useor diversion of the flow and speed control programmes, such as the MRH-S50-13 type aircraft, that is, in the rapid mobilization of machinery, to stop carrying motor oil, only to run motor oil so that the boring machine has two Walking speed.3 determination complete machine main technology senate parameter Mechanical Roadheader complete machine main technical parameter including size senate parameter (length ×width ×highly); we ight parameter, parameter of movement and dynamic parameter.3.1 size parametersComplete machine length, width of the size directly related to its turning radius, Recommended light-length ≤ 7.5 m, medium-length ≤ 8.5 m, heavy machine ≤ l0m, the corresponding width were ≤ 1.6 m, ≤ 2.5 m, ≤ 3 m. The complete machine relates its tendency, the static stability highly directly, the adaptation scope and passes quality, therefore lower better. The current development trend of Chinese and foreign models is the dwarf models, medium and heavy-high 1.6 ~ 2 m, special light, light machine the height of 1.4 ~ 1.6 m. Roadheader to dig the biggest section of roadway, the minimum height and width should be designed to meet the requirements of the mission. Undercover depth of 250 ~ 400 mm, ground clearance C = B/13 +84 (mm), B for the two track distance). Middle-long conveyor entrance to the expected high degree of the best 400 mm, length of track ground with the center distance L B ratio for L / B ≤ 1.6.3.2 weight parametersThe complete machine dead weight is the mechanical roadheader - an important parameter, the engine weight too is light, the work stability drops, when swinging cutting can occur fishtails the phenomenon, the cutting efficiency drops, truncation tooth rate of wear increase; Heavy-weight, poor mobility, flexibility to decline. The self-respect as it may be w = (t) estimates, in the N-type body for cutting power, kW; V for the cutting head on average cutting speed, m / s; can also be Roadheader with reference to the existing analog method to determine , machine-(t) and cutting power (kW) ratio of 0.25 to 0.4. For general coal, rock bottom, the allowable value≤ 0.14 MPa; muddy for the water to soften the shale bottom,≤ 0.05 MPa.3.3 movement parametersCutting the movement parameters: cutting head of the average cutting speed V: on the one-way coal and rock compressive strength of σ c ≤ 40 MPa, V = 3 ~ 3.5m / s;σ c ≤ 60MPa, V = 2 ~ 2.5m / s, σ c > 60MPa. V = l ~ 2m / s. But eventually cuttingspeed by cutting technology to determine.3.4 dynamic parametersRoadheader-driven power sources are used Motors. Cutting power body size. In fact the general use of analogy, combined with roadheader some personality andexperience factors to determine. Roadheader in the operating process, the vertical axis and the horizontal axis-of the need for adequate cutting edge and push forward swing (horizontal and vertical) force. According to Russia (the former Soviet Union) in the laboratory test results that the cutting of coal and rock platts hardness f = 4 ~ 6 (equivalent to 0 C = 40 ~ 60MPa), grinding coefficient F = 5 ~ 7mg/mm2. Cutting the shaking force (traction) Pv = (1 ~ 1.34) P, P = M / Rcp, in the P-cutting head for the average cutting edge; Rcp cutting head for the average radius; M for cutting the head of the rated torque. Cut the feeding of (axial thrust) R; (1.8 ~ 2.5) Pv, this force should be no larger than the floor slippery track at the limits of traction.3.5 technical and economic indicatorsQ = (m3/min), in the sx-cutting head for the verticalcross sectional area, m2: Vn for the cutting head of cutting swing speed, m / min. Roadheader designed life, in the international advanced products up to 3 to 5 years, during which the need of major repair or wells, the general domestic product for 1 to 2 years.4 in accordance with design requirements. Determine the parameters of the main components and their relationship between the connector4.1 cutting agencies and technical parameters of the established link between1) Cutting-agency technical parameters of cutting the head with thegeneral pick for the double-headed or three spiral layout. Cutting head speed n = 20 ~ 65r/min, a sharp pick cutting the average speed V = 1.5 ~ 2.5m / s, cutting swing speed Vn = 0.8 ~ l0m / s. Cut-off line from t = 20 ~ 50mm, (when cutting coal from the value of all-time for small value). Average single-pole/double-throw force should reach: f4 grade coal and rock F ≥ 2500 N, f6 grade coal and rock F ≥ 5000 N, f8 grade coal and rock F ≥ 12000 N, pick the best angle for the installation of 45 ° ~ 48 °. 2) Cutting the link .Cutting agencies cantilever Chaxing-installed in front of the fixed-Chaxing rotary table, the turret to the rack. According to cutting agencies in the course of operating the force and torque, the application of MT475-1996 "cantilevered Roadheader rotary bearing type, the basic parameters and technical requirements" selected rotary bearing the structural type, determined by calculatingslewing ring size specifications. If the user does not require a cantilever stretching structure, is generally not recommended.4.2 shipping agencies determine the parameters1) Loading mechanism Loading bodies and Middle conveyor used linkage or single-action mode, loading the bodies rake claws speed is generally 25 ~ 48 r / min. Star Ferry's speed can be slightly higher than some. Using direct-drive hydraulic motors, the maximum output torque rated torque for calculating the value of 1.5 times. Shovel coal-general of the tilt angle to 21 ° ~ 25 °, it should be the width of track, spacious than the 0.6 ~ 1.2 m, declining position should not be less than the minimum depth of undercover maximum height should be increased to 350 ~ 400 mm. 2) Intermediate conveyor Middle conveyor chain may be single or double-stranded chain structure of the ring chain, chain-speed should not exceed 0.92 m / s, using the U.S. chain of universal sleeve roller chain single chain, the chain speed should not exceed 2.5 m / s, generally from 1.6 ~ 2 m in order to meet the changing demands a high degree of unloading, the tail should be set up multi-stage hydraulic cylinders to achieve take-off and landing movements, raising the minimum height for the hopper and a high degree of around 300 mm. If the tail need to swing around, the United States must adopt a universal sleeve roller chain, to set the location of the side-effect hydraulic cylinder to achieve the tail swingaround 45 °, to expan d the width of unloading.4.3 running track and identify the technical parameters of connectivity betweena)walking track drivers and transmission patterns have the following two ways, the overall design and layout determined at the time one of them.1) Drive a motor-driven than reducer (i ≈250) →led initiative sprocket. Can only establish a walking speed of 5 ~ 7.5 m / min. 2) The speed of a hydraulic motor torque direct drive or take the initiative sprocket of a slowdown in high-speed motor driven me a sprocket can take the initiative to achieve rapid mobilization and the need to slow operations, walking speed of 0 ~ 10 m / min of no - Speed. b) tracked the transmission link between Structure has two sliding and rolling, sliding simple structure, the resistance of larger, the special light, light and medium-sized roadheader recommend sliding structured. Rolling resistance smaller operation, crawler-crawler at the bottom andwear small chain of contacts. Heavy and severe roadheader recommend using this structure type. Track-installed at the bottom of the supporting wheels, each bearing capacity should be not less than 50 percent of weight, distance is generally tracked the plate pitch 1.5 times.4.4 the hydraulic system of technical parameters establishedHydraulic system of technical parameters should be determined in the hydraulic design calculations. The pressure should not be rated higher than the 20 ~ 25 MPa. A hydraulic motor in the system should be set up power transmission cooler, the system in the optional round series at the pump, rated pressure announced that the following 20 MPa. Selection of pumps and motors of the Anyu should be around 1.5. Each loop system in the pressure relief valve is set for the rated pressure of 1.8 to 2.2 times suitable.4.5 electronic control system identified the main technical parametersElectronic control system of power supply voltage should be roadheader models to determine the size of pressure levels, special light, light machine should be elected 660 V, medium and heavy aircraft should be elected 660 V/1140V. Some momentum in the electrical circuit components,the power supply should meet the range of 70% to 115% of the requests.4.6 other supporting systems1) Spray system, cutting nozzles installed in the front organizations cantilever pressure for 1.5 MPa. Spray nozzle within the system installed in cutting the first pick in the back seat of the spray system pressure of not less than 4 MPa. Cutting rock on the case should be to increase water pressure and water. 2) Inside and outside the water spray system shall not exceed the actual health roadheader capacity of 6 to 8 percent, or stagnant water in the face of slime.5 the overall calculation of the necessary plans and systemsSuch as in roadheader design and overall layout is complete with two of the main components of each system and the main structure, the basic technical parameters have been determined, theComplete machine should carry out the necessary calculations and the overall system, and other plans. 1) Cutting agencies roadheader static and dynamic stability of the calculation. 2) Transmission and hydraulic components of the electronic control system of power calculation.3) Hydraulic system heat balance calculations. 4) Drawing transmission, hydraulic, electronic control system plans. 5) Drawing cutting sections of roadway.6 ConclusionRoadheader design is roadheader design projects in the technical design of the components. It is the key to the design of the overall performance parameters of reasonable choices, the assembly of each system and optimize the design standards, in particular, cutting the cutting technology is particularly important. Roadheader described in this paper, the overall design is still based on traditional design, dynamics, kinematics, the calculation of the force should be wider use of modern design methods, such as conceptual design, 3D design kinematics, dynamics simulation technology, limited Yuan design and optimize the design. At the same time, the international community should be extensively studied this aspect of the new design for my use, to enhance our design standards, we have accumulated experience in the design, to produce a safe, reliable, high-performance high-end products.译文：悬臂纵轴式掘进机的总体设计总体设计是机械产品设计过程中的重要内容和主要环节，它是在方案设计之后紧接着进行的设计工作。

机械类外文文献翻译(中英文翻译)英文原文Mechanical Design and Manufacturing ProcessesMechanical design is the application of science and technology to devise new or improved products for the purpose of satisfying human needs. It is a vast field of engineering technology which not only concerns itself with the original conception of the product in terms of its size, shape and construction details, but also considers the various factors involved in the manufacture, marketing and use of the product.People who perform the various functions of mechanical design are typically called designers, or design engineers. Mechanical design is basically a creative activity. However, in addition to being innovative, a design engineer must also have a solid background in the areas of mechanical drawing, kinematics, dynamics, materials engineering, strength of materials and manufacturing processes.As stated previously, the purpose of mechanical design is to produce a product which will serve a need for man. Inventions, discoveries and scientific knowledge by themselves do not necessarily benefit people; only if they are incorporated into a designed product will a benefit be derived. It should be recognized, therefore, that a human need must be identified before a particular product is designed.Mechanical design should be considered to be an opportunity to use innovative talents to envision a design of a product, to analyze the systemand then make sound judgments on how the product is to be manufactured. It is important to understand the fundamentals of engineering rather than memorize mere facts and equations. There are no facts or equations which alone can be used to provide all the correct decisions required to produce a good design.On the other hand, any calculations made must be done with the utmost care and precision. For example, if a decimal point is misplaced, an otherwise acceptable design may not function.Good designs require trying new ideas and being willing to take a certain amount of risk, knowing that if the new idea does not work the existing method can be reinstated. Thus a designer must have patience, since there is no assurance of success for the time and effort expended. Creating a completely new design generally requires that many old and well-established methods be thrust aside. This is not easy since many people cling to familiar ideas, techniques and attitudes. A design engineer should constantly search for ways to improve an existing product and must decide what old, proven concepts should be used and what new, untried ideas should be incorporated.New designs generally have "bugs" or unforeseen problems which must be worked out before the superior characteristics of the new designs can be enjoyed. Thus there is a chance for a superior product, but only at higher risk. It should be emphasized that, if a design does not warrant radical new methods, such methods should not be applied merely for the sake of change.During the beginning stages of design, creativity should be allowedto flourish without a great number of constraints. Even though many impractical ideas may arise, it is usually easy to eliminate them in the early stages of design before firm details are required by manufacturing. In this way, innovative ideas are not inhibited. Quite often, more than one design is developed, up to the point where they can be compared against each other. It is entirely possible that the design which is ultimately accepted will use ideas existing in one of the rejected designs that did not show as much overall promise.Psychologists frequently talk about trying to fit people to the machines they operate. It is essentially the responsibility of the design engineer to strive to fit machines to people. This is not an easy task, since there is really no average person for which certain operating dimensions and procedures are optimum.Another important point which should be recognized is that a design engineer must be able to communicate ideas to other people if they are to be incorporated. Communicating the design to others is the final, vital step in the design process. Undoubtedly many great designs, inventions, and creative works have been lost to mankind simply because the originators were unable or unwilling to explain their accomplishments to others. Presentation is a selling job. The engineer, when presenting a new solution to administrative, management, or supervisory persons, is attempting to sell or to prove to them that this solution is a better one. Unless this can be done successfully, the time and effort spent on obtaining the solution have been largely wasted.Basically, there are only three means of communication available tous. These are the written, the oral, and the graphical forms. Therefore the successful engineer will be technically competent and versatile in all three forms of communication. A technically competent person who lacks ability in any one of these forms is severely handicapped. If ability in all three forms is lacking, no one will ever know how competent that person is!The competent engineer should not be afraid of the possibility of not succeeding in a presentation. In fact, occasional failure should be expected because failure or criticism seems to accompany every really creative idea. There is a great deal to be learned from a failure, and the greatest gains are obtained by those willing to risk defeat. In the final analysis, the real failure would lie in deciding not to make the presentation at all. To communicate effectively, the following questions must be answered:(1) Does the design really serve a human need?(2) Will it be competitive with existing products of rival companies?(3) Is it economical to produce?(4) Can it be readily maintained?(5) Will it sell and make a profit?Only time will provide the true answers to the preceding questions, but the product should be designed, manufactured and marketed only with initial affirmative answers. The design engineer also must communicate the finalized design to manufacturing through the use of detail and assembly drawings.Quite often, a problem will occur during the manufacturing cycle [3].It may be that a change is required in the dimensioning or tolerancing of a part so that it can be more readily produced. This fails in the category of engineering changes which must be approved by the design engineer so that the product function will not be adversely affected. In other cases, a deficiency in the design may appear during assembly or testing just prior to shipping. These realities simply bear out the fact that design is a living process. There is always a better way to do it and the designer should constantly strive towards finding that better way.Designing starts with a need, real or imagined. Existing apparatus may need improvements in durability, efficiently, weight, speed, or cost. New apparatus may be needed to perform a function previously done by men, such as computation, assembly, or servicing. With the objective wholly or partly defined, the next step in design is the conception of mechanisms and their arrangements that will perform the needed functions.For this, freehand sketching is of great value, not only as a record of one's thoughts and as an aid in discussion with others, but particularly for communication with one's own mind, as a stimulant for creative ideas.When the general shape and a few dimensions of the several components become apparent, analysis can begin in earnest. The analysis will have as its objective satisfactory or superior performance, plus safety and durability with minimum weight, and a competitive east. Optimum proportions and dimensions will be sought for each critically loaded section, together with a balance between the strength of the several components. Materials and their treatment will be chosen. These important objectives can be attained only by analysis based upon the principles ofmechanics, such as those of statics for reaction forces and for the optimumutilization of friction; of dynamics for inertia, acceleration, and energy; of elasticity and strength of materials for stress。

挖掘机论文中英文资料外文翻译文献外文文献A Summary of Small-size Excavators Home and Abroad I. The brief introduction of hydraulic excavatorParts such as the hydraulic excavator is by engine, hydraulic system and works device and walks device and electric control etc are formed. The hydraulic system is formed by hydraulic pump, control valve, hydraulic cylinder, hydraulic pressure motor, pipe route and fuel tank etc. The electric control system includes supervision dish, motor control system, pump brain and various kinds of sensor and solenoid valves etc. The hydraulic excavator is general by the work device and turns round the device and walks device three is mostly formed. According to his construction and use, we can differentiate : many kinds of types such as caterpillar tread type, tyre type, walk type, full hydraulic pressure, half hydraulic pressure, turns round entirely, not turns round entirely, utility version, mould for a special purpose, the joining with a hinge type and arm type stretched out and drawn back etc.The work device is directly accomplishing the device that excavates the assignment. It has been joined with a hinge by moves the arm, fights the pole and shovels the fill etc three parts. Moving that the arm rises and falls and the pole fought stretches out and draws back and shoveling fighting moves all with moving back and forth type two effect hydraulic cylinders control. In order to suit the needs of various difference construction school assignments, the hydraulic pressure excavator can be joined in marriage loading many kinds of work devices, if excavating and many kinds of school assignment machines and tools such as lifting job, loading, leveling, clamp and pushes soil and shock hammer etc.Turning round and walks the device is the organism of hydraulic pressure excavator, upper setting up power-on device and transmission system of turntable. The engine is the power supply of hydraulic pressure excavator, and adopts diesel oil will also can modify the electromotor in the convenient place mostly.The hydraulic drive system by way of the hydraulic pump with the engine the motivepromotion work device moves, thus accomplishes the various school assignments. Take more PV-200's mould hydraulic pressure excavators of use in building site as the example. This machine adopts the type the opening center load of advanced version to be passed feeling system (OLSS). This system is with oblique of control type oblique the method of angle (export volume of flow ) variable plunger pump, and reduced the power delivery of engine, thus reduces the oil consumption burnt, and is one kind of saving energy mould system. The characteristic of this kind of hydraulic system is: the fixed torque is controlled, and it is unchangeable to keep the hydraulic pump drive torque, and year absolutely control can reduce the off-loading loss of school assignment time; Oil capacity is controlled, and the export volume of flow of hydraulic pump in the time of can reducing neutral gear and fine control reduces the power loss.The history of the first hand excavator was published up to now to have more than 130 years, and went through from the steam drive fill to turn round that the machinery turns round the developing the course step by step of the complete automatic hydraulic pressure excavator of excavator and application mechanical and electrical liquid integration technology to power drive and the internal-combustion engine drive in the time. The application owing to the hydraulic technique had to join in marriage on the tractor loading hydraulic pressure to anti- the type hanging which shoveled machinery in the 1940’s, and developing out the pulling type at the initial stage of in the 1950’s w ith middle period in succession, to turn round the full hydraulic pressure of hydraulic pressure excavator and caterpillar tread type entirely mechanical. Initial stage the trial hydraulic pressure excavator is the hydraulic technique that adopts plane and machine tool, lacking the hydraulic pressure component that is suitable in the mechanical various operating modes, it is stable inadequately to make the quality, and necessary is not completely yet. From in the 1960’s, the hydraulic pressure excavator is entered the popularization and in vigorous development stage, and mechanical manufacturing plant and the breed of each country increases very fast, and the output is rapidly increased. 83% of the mechanical gross output was occupied to hydraulic pressure excavator output, and is close to 100% at present 1968-1970 certain period.ⅡSmall excavator development and its tendency20th century 80 ~ 90's small mechanical device in construction and soon in municipal engineering, transportation, pipeline has displayed abigger superiority and can rapidlymakes thesmall excavator mainly to use in the city the constructionconstruction and generally left a bigger contribution,gradually became in the city construct ionto have the representative construction machinery.The small excavator development mainly relies on the urbanconstruction development, because city transformation, constructionconstruction more, the request construction time short, theconstruction machinery affects small, safe, the low pollution, theradius of gyration to the environment is small, is advantageous fortransports as well as has with the city scenery appearancecoordination outward appearance, the small excavator has satisfied thecity each kind of work request, can maximum limit display itsproductivity in the city narrow working space, therefore has theunique superiority.1. The development of small excavatorsThe small excavator mainly uses in the city the constructionconstruction and the general housing repairs and maintains and so onthe work, the request has the good operating performance and therotation performance.Initial small excavator by tire type primarily, because the tire typewalks the natural in the soft ground and the passing difference,afterwards gradually by the marching substitution, and in moved thearm strut organization place to increase the rotation organizationabout, enabled the entire work equipment the relative organism tocarry on swings, completed the trench sidewall excavation renovationwork behind, but this kind of small excavator excavation scope wassmall, cannot realize the material. Hereafter, the small excavator increased upside has rotated theorganization, has solved behind themetial and so on the problem, enhancedthe excavator operating performance, formed the small excavator thebasic structure. Afterwards, the small excavator in the radius ofgyration, behind the field of vision, moved aspect and so on armelevation angle, machine capability has the further improvement,develops for the present standard type.2.Technical progressesSmall excavator working conditions majority of in city, in order toprevent walks when damages the road surface, starts from the 80's touse the rubber caterpillar band, and gradually obtains thepopularization. A rubber caterpillar band heavy wheel is when theinternal iron circuit board the movement, the hard circuit board jointplace and the heavy wheel contact falls to the ground, becomes walksthe destruction road surface main reason. Before uses the width shapeiron circuit board, a rubber caterpillar band heavy wheel diameter isbigger, therefore when approaches the ground, this slit changes in abig way, creates the caterpillarheavy wheel, onlywas the hard circuit board which in the caterpillar band used changesnarrowly, therefore when contacted the ground the slit changesslightly, reduced to the damage of ground.Rear area the small rotation excavator rotation rear part size isextremely small, in order to guarantee the excavator work thestability, must have the enough counterweight, and in does notincrease the mechanical weight under the premise, uses increases thecaterpillar band length and widens the chassis and so on the effectivemethod.But, the chassis width is transported the truck width the limit, forsolves this problem, has used ViCTAS in the super small excavator (Vio- Crawler Technology by Advanced Stability) the technology.fortablenessThe small excavator majority of seals cab, has not rained when thechair frequently drips wet by the rain seeps. In order to solve thisproblem, the use surface and the interior gather a peaceful fat rubberbody to manufacture has not sewn the seam the chair, cannot againfrom sew the seam place destruction, the durability also can enhance,becomes the complete waterproofing chair.Impels the small excavator market fast development the factor:(1) The small excavator has the widespread serviceable small excavatorvolume small, mobile is flexible, extremely is suitable for work andso on cities each kind of pipelining, foundation construction, publicutilities as well as house service. The small excavator compactvolume, the special design enable its to carry on the work in theenvironment which the large-scale excavator is unable to construct.(2) The small excavator has the multi-purpose small excavator truemerit is it has multi-purpose. The small excavator can install manyauxiliary works machines and tools, like the installment brokenhammer, the hydraulic pressure pliers use in the lightweightdemolision work, installs a clamp to use in to eliminate the work,installs the drum, the plate uses in the trench to fill in buriesthe compaction, the installment turns on lathe digs drills uses in thedrill hole, the lift hook uses in to hoist up heavy item and so on.(3)The small excavator is advantageous for the transportation and oneof shift work location small hydraulic pressure excavator market rapidexpansion reasons should belong to its size and the weight. The smallexcavation function conveniently shifts in each job location, thesmall excavator does not need the large-scale trailer perhaps theheavy-duty truck carries on the transportation, the small transportmeans may deliver. Like this not only can facilitate(4) Small excavator bright work characteristic: The rear part radiusof turn for the zero design, causes the small excavator not to need inthe work space limited environment mean industry time excavatoroperator to consider the job location is, whether thus enable theoperator to have the obstacle to hinder the excavator the rotation tosuffice wholly absorbed to the scoop operation, this has alsoprevented around the job location the building as well as theexcavator own damage.(5) Invests the repayment rate to be high, the cost recycles quicklyThe small excavator price is cheap, the cost recycles quickly.Slightly digs take the 6t level as the example, American, the Europeandate brand machine price about 400,000 Yuan, South Korea's machineprice about 320,000 Yuan, the domestically produced machine price is30 ~ 320,000 Yuan some brands is lower; But the 20t level center digsthe price in 70 ~ 1 million Yuan. The higher investment repayment ratecauses the small excavator deeply the general center small earthworkconstruction to contract owner's welcome.4 Small excavators technological development tendenciesThe small excavator technological development complied with the globaldiversification job location the demand, has experienced more than 30years history successional variation process, passes through theunceasing improvement consummation, in aspect and so on technicalperformance, job function, work efficiency, security, environmentalprotection, energy conservation and maintenance maintenance had thelarge scale enhancement, has formed the quite consistent technicalstandard and the work standard. Mainly manifests in following severalaspects:(1) The tailless rotation and moves the arm deflection technology totake slightly digs the basic concept to move the arm deflection andthe tailless rotation function later period promotes in the 1990s facethe world market. Moves the arm deflection in the organism front part,but does not have the organization to be able to realize is locatednearby the lower part of wall the direct excavation work to havefrequently to move the fuselage. The tailless rotation structureapplication, causes it when the neck of land work does not need toworry the rear part the collision. The tailless rotation structuraldesign difficulty lies in rotates in the platform the generalarrangement, the dynamic system thermal equilibrium solution as wellas the entire machine stable solution. But moves the arm deflectionorganization the design difficulty to lie in an articulation positionthe determination and the hinge body manufacture technology.(2) New hydraulic control technologyserviceability is good, has the good efficiency, may carryon the high efficiency, the powerful work. The new fluid environmentcompatibility presses the system not to shoulder the size theinfluence, completely needs the oil of the hydraulic pressure system, the current capacity accordingto the control handle scope distribution point, definitely may deferto operator's intention with ease to complete the work. At the sametime, because the engine load is small may avoid the current capacitythe senseless loss, can realize slightly moves the operation and thecompound operation. The new hydraulic control technology applicationalso can increase the dynamic output, enhances the work speed, reducesthe fuel consumption.(3)Security performanceHas the strict legal rule in the European market and the North Americamarket to the security, the equipment security performance can givethe operator to provide the relieved work the environment, enhancesoperator's security. The small excavator security performance mainlymanifests in the cab ROPS/FOPS design below, should satisfy theperformance requirement in the cab experiment:①May satisfy must energy absorption;② May satisfy must anti- load;③The crew member safety zone enough is big.(4) Environmental protection technologyMainly manifests in the power, the low oil consumption, cleanlydischarges the engine in the application. The new engine shouldsatisfy the American EPATier2 standard and the European EU standard,will cause the environmental pollution the compound to discharge thecontrol in the threshold. The new engine simultaneously reduced thevibration and the noise, is beneficial to the environmental protectionand operator's health.(5) Man-machine project technologyThe cab conforms to the man-machine engineering principle,internal spacious, field of vision open, modelling artistic, the easeof operation, reduces effort the measuring appliance demonstrationdirect-viewing, is accurate, can provide one kind of comfortableoperating environment to the pilot, fully reduces pilot's weariness.(6) Services the maintenance technologyMaintains from the current maintenance to the regular inspectionservice, the simplification operation is extremely essential, canenhance the machine the reliability, makes the machine throughout tomaintain the good condition. Must cause the daily inspection side,operation.Maintenance repair then quickly dnd simplely, but fast carries on theinternal spare part and the system inspection and the service. Moreover, in the design must fully consider prevents the machine theaccident damage.Such as the cowling, the guard plateguards against the collision structural design;Moves the arm hydraulic cylinder guard plate design; Fuel oil tank draw-offvalve; The independence bulldozes the board hydraulic pressure hosedesign; Waterproofing electric system design; In the work installmenthose sets at the design; X frame and halfway up the mountainsidecaterpillar band design; The engine machine oil filter elementreplacement time lengthens; Has forerunner system which the pipelinefilters; Dual spatially filters structure design and so on.5 ConclusionsSociety's development has a more tremendous influence to the smallexcavator, at present the overseas small excavator had the suitable development, like Carter other forces, company and so on Hitachi,small pine, Mitsubishi, the small excavator product has formed theseries, and in unceasingly carries on the development, the expandeduse, the increase appendix type. The domestic small excavatordevelopment has also obtained the certain result, but all needsfurther to improve and the consummation in the technology and theproduction.中文译文国内外小型挖掘机发展综述一、液压挖掘机简介液压挖掘机是由发动机、液压系统、工作装置、行走装置和电气控制等部分组成。