CENTRIFUGAL PUMP IN
CHEMICALPRODUCTIONAPPLICATION
Centrifugal pump in chemical production, this is most widely used because of its performance wide range (including flow, pressure head of media properties and ShiYing sexual), small volume, simple structure, easy operation, flow uniformity, low malfunction, long service life, CaoZuoFei are lower cost and prominent advantages.
(1)centrifugal pump principle of work
Centrifugal pump working principle is: centrifugal pump so can turn the water away is because only centrificating. Water pump before work, pump body and feed water full line must be cans in vacuum condition, when the impeller fast turns, leaf prompted water quickly spin, spin in the water under the action of the centrifugal force, pump impeller flew in from the water was thrown in the central part of the impeller, after forming vacuum area. Water in the water atmospheric pressure (or water pressure) under the action of water pipe pressure came through a tube. This cycle unceasingly, can achieve continuous pumped. In the centrifugal pump is worth mentioning: before initiating must to the pump housing filled with water, can start after, otherwise will cause, the vibration of the pump body, thus reduce heat pump, damage to (hereinafter referred to as "cavitation erosion") cause equipment accident!
Centrifugal pump is a lot of more phyletic, classification methods common has the following kinds of kind: 1, press the impeller inhaled way points: single suction style centrifugal pump double suction type centrifugal pump. 2, press the impeller number points: single grade centrifugal pump mulfistage centrifugal pump. 3, according to the structure of impeller points: open impeller centrifugal pump impeller half open centrifugal pump closed impeller centrifugal pump. 4, according to work pressure points: low voltage centrifugal pump medium centrifugal pump
high-pressure centrifugal pump. 5, according to pump shaft position points: horizontal centrifugal pump edge vertical centrifugal pump.
(2) basic structure, centrifugal pumps
Centrifugal pump is the basic structure by six parts, it is respectively, pump body, impeller pump shaft, bearing, sealing ring, the stuffing box.
1, centrifugal pump impeller is higher than the core part, its great strength, speed and a impeller blades of the main function, impeller before assembly through the static balance experiments. Internal and external surface requirements on the impeller of smooth, to reduce water friction losses.
2, the pump body also called pump shell, it is the pump body. Play support fixed effect, and is connected to install bearing bracket.
3 and the role of pump shaft couplings and motor was borrowed, will connect to the torque motor impeller, so it is the main component of mechanical transmission.
4, bearing is set in the pump shaft support of pump shaft components, a rolling bearing and sliding bearing two kinds. Rolling bearings use butter as lubricant refueling appropriate to general for 2/3 ~ 3/4 volume too much, too little and can calorific a sound and fever! Sliding bearings use transparent oil for lubricant, refuels to oil level line. Too much oil to leak and drift along the pump shaft, too little bearing and melech overheating burnt out cause an accident! The water pump operation process of the highest temperature bearing in general 85 degrees running in about 60 degrees, if gao will find the reasons (whether have impurities, whether black, oily water) and deal with whether!
5, sealing ring and say minus leak rings. The import and pump impeller shell of the gap between will cause the water pump high-pressure zone within the clearance flow by low pressure area, the influence of the pump, low efficiency, &safe-durable! Gap with the pump impeller had caused moment shell friction wear. In order to reduce leakage increased reflow resistance, delaying the impeller and pump shell used in the pump housing life, with inner and impeller sealing, department of foreign aid in the gaps remain sealed between 0.25 ~ 1.10 mm advisable.
6, stuffing box, mainly by packing rings, packing cone, water storage tube packing gland, composed. The role of the stuffing box is mainly to closed pump shell with the space between the pump shaft, don't let pump of water inside don't flow to the outside to also don't let the outside air into the pump inside. Always keep the vacuum pump inside! When the pump shaft and packing friction heat water control
water to be about to rely on water circle make packing cooling! Maintain normal operation of pump. So the water pump operation circuit checking process to the stuffing box examination is special attention should be paid to! About 600 hours in operation for packing replacement to.
(3) centrifugal pump impeller and other components
1. Centrifugal pump impeller
Centrifugal pump impeller is the key components.
according to the mechanical structure can be divided into closed, semi-enclosed and open 3 kinds. Closed impeller suitable for conveying clean liquid. Semi-enclosed and open impeller suitable for conveying containing solid particles of suspending liquid in the efficiency of, this kind of pump low.
Closed and semi-enclosed impeller in operation, leave the impeller's part of high pressure fluid can leak into the impeller and pump shell cavity, between the side because of impeller suction pressure low, liquid at the entrance is liquid in the role of the pressure before and behind impeller to differ, they generate pointing the suction side impeller axial thrust. This force to promote the suction side impeller pump impeller and mobile, cause the contact point of moab shell caused serious damage, the vibration of the pump unit, destroying the normal operation of pump. HouGaiBan in impeller drilled several holes, can reduce the pressure on both sides of the impeller is poor, and decrease the harmful effects of axial thrust, but also reduced the pump efficiency. These holes called balance holes.
according to absorb fluid can be divided into different ways of impeller with single suction style double suction type two kinds, single suction style simple structure, liquid only impeller from one side of the inhalation. Double suction style impeller can simultaneously from impeller symmetry to inhaled liquid, it not only has
a greater ability to absor
b fluid, and basically eliminate the axial thrust.
(3) on the impeller blade according to the geometrical shape, can be bent, radial after blade is divided into three, before and after bending due to bend the kinetic energy transfer liquid leaves, so for static pressure can be used extensively.
2. The centrifugal pump impeller
In order to reduce leave the liquid directly into the pump impeller shell caused by impact energy loss in the impeller and pump shell, between sometimes device a fixed blade and contain keep-off device. The blade into the pump impeller shell has gradually turned into the liquid flow, make continuous expansion and partial kinetic energy effectively converted to static pressure can. Multistage centrifugal pump impeller usually are installed.
The snail shaped pump, impeller blade and the bent on after all can improve kinetic energy to guide the conversion, and therefore can plenum are regarded as turn can device.
3. Shaft sealing device
Because of pump shaft rotation and pump shell stationary, and in the axis and the contact point of the pump housing must have certain gap. To avoid pump internal high-pressure liquid leakage along the gap, or prevent outside air from the opposite direction into the pump must set within the shaft seal device. Centrifugal pump shaft sealing device has a filler letter and mechanical (end) seal. Stuffing box is will pump shaft through pump shell ring gap to finish seal, in which loaded soft packing (such as oil or coating graphite baptized of asbestos rope, etc.). Mechanical seal is by an outfit in the acting-ring axis and another fixed in the pump housing formed by static ring. Two rings of end borrow spring force tiejin each other relative rotation, and played the sealing effect. Mechanical seal applies to seal higher occasions, such as the conveying acid, alkali, inflammable, explosive and poisonous liquid.
(4)the centrifugal pump introduces below several important performance curve.
1, flow - head characteristic curve
It is the basic of centrifugal pump performance curve. Less than 80 than speed centrifugal pump has the characteristics of rise and fall, both sides among (both under convex curved), says hump performance curve. In 80 ~ 150 than speed centrifugal pump has between plain performance curve. More than 150 RPM centrifugal pump performance curves with steep drop. In general, when flow hours, head is high, with the increase of flow is decreasing. Head
2, flow - power curve
The shaft power increases with the flow, when flow Q = 0, the corresponding shaft power is not equal to zero, and for certain value (about the normal operation of the 60 percent). The power consumed mainly by the mechanical loss. This is full of water pump, if long time running, will lead to the temperature rising pump, pump shell, bearing can calorific, serious when may make pump body thermal deformation, we called "stuffy head", then head for maximum, when water valve gradually opened, the flow rate will increase, shaft power also slow increase.
3, flow - efficiency curve
Its curve shape, when flow xiangshan head is equal, efficiency and equal to zero, with the increase of flow, efficiency, but also gradually increase the efficiency increased to a certain value has decreased, after a high efficiency in highest efficiency point near, efficiency is higher, this area is called efficient area.
离心泵在化工生产的应用
离心泵在化工生产中应用最为广泛，这是由于其具有性能适用范围广（包括流量、压头及对介质性质的失迎性）、体积小、结构简单、操作容易、流量均匀、故障少、寿命长、购置费和操作费均较低等突出优点。
（一）、离心泵的工作原理
离心泵的工作原理是：离心泵所以能把水送出去是由于离心力的作用。水泵在工作前，泵体和进水管必须罐满水行成真空状态，当叶轮快速转动时，叶片促使水很快旋转，旋转着的水在离心力的作用下从叶轮中飞去，泵内的水被抛出后，叶轮的中心部分形成真空区域。水原的水在大气压力（或水压）的作用下通过管网压到了进水管内。这样循环不已，就可以实现连续抽水。在此值得一提的是：离心泵启动前一定要向泵壳内充满水以后，方可启动，否则将造成泵体发热，震动，出水量减少，对水泵造成损坏（简称“气蚀”）造成设备事故！
离心泵的种类很多，分类方法常见的有以下几种方式：1、按叶轮吸入方式分：单吸式离心泵双吸式离心泵。2、按叶轮数目分：单级离心泵多级离心泵
3、按叶轮结构分：敞开式叶轮离心泵半开式叶轮离心泵封闭式叶轮离心泵
4、按工作压力分：低压离心泵中压离心泵高压离心泵。
5、按泵轴位置分：卧式离心泵边立式离心泵。
（二）、离心泵的基本构造
离心泵的基本构造是由六部分组成的，分别是叶轮，泵体，泵轴，轴承，密封环，填料函。
1、叶轮是离心泵的核心部分，它转速高出力大，叶轮上的叶片又起到主要作用，叶轮在装配前要通过静平衡实验。叶轮上的内外表面要求光滑，以减少水流的摩擦损失。
2、泵体也称泵壳，它是水泵的主体。起到支撑固定作用，并与安装轴承的托架相连接。
3、泵轴的作用是借联轴器和电动机相连接，将电动机的转距传给叶轮，所以它是传递机械能的主要部件。
4、轴承是套在泵轴上支撑泵轴的构件，有滚动轴承和滑动轴承两种。滚动轴承使用牛油作为润滑剂加油要适当一般为2/3～3/4的体积太多会发热，太少又有响声并发热！滑动轴承使用的是透明油作润滑剂的,加油到油位线。太多油要沿泵轴渗出并且漂贱，太少轴承又要过热烧坏造成事故！在水泵运行过程中轴承的温度最高在85度一般运行在60度左右，如果高了就要查找原因（是否有杂质，油质是否发黑，是否进水）并及时处理！
5、密封环又称减漏环。叶轮进口与泵壳间的间隙过大会造成泵内高压区的水经此间隙流向低压区，影响泵的出水量，效率降低！间隙过小会造成叶轮与泵壳摩擦产生磨损。为了增加回流阻力减少内漏，延缓叶轮和泵壳的所使用寿命，在泵壳内缘和叶轮外援结合处装有密封环，密封的间隙保持在0.25～1.10mm之间为宜。
6、填料函主要由填料，水封环，填料筒，填料压盖，水封管组成。填料函的作用主要是为了封闭泵壳与泵轴之间的空隙，不让泵内的水流不流到外面来也不让外面的空气进入到泵内。始终保持水泵内的真空！当泵轴与填料摩擦产生热量就要靠水封管住水到水封圈内使填料冷却！保持水泵的正常运行。所以在水泵的运行巡回检查过程中对填料函的检查是特别要注意！在运行600个小时左右就要对填料进行更换。
（三）离心泵的叶轮和其它部件
1．离心泵的叶轮
叶轮是离心泵的关键部件。
(1)按其机械结构可分为闭式、半闭式和开式三种。闭式叶轮适用于输送清洁液体；半闭式和开式叶轮适用于输送含有固体颗粒的悬浮液，这类泵的效率低。
闭式和半闭式叶轮在运转时，离开叶轮的一部分高压液体可漏入叶轮与泵壳之间的空腔中，因叶轮前侧液体吸入口处压强低，故液体作用于叶轮前、后侧的压力不等，便产生了指向叶轮吸入口侧的轴向推力。该力推动叶轮向吸入口侧移动，引起叶轮和泵壳接触处的摩损，严重时造成泵的振动，破坏泵的正常操作。在叶轮后盖板上钻若干个小孔，可减少叶轮两侧的压力差，从而减轻了轴向推力的不利影响，但同时也降低了泵的效率。这些小孔称为平衡孔。
(2)按吸液方式不同可将叶轮分为单吸式与双吸式两种，单吸式叶轮结构简单，液体只能从一侧吸入。双吸式叶轮可同时从叶轮两侧对称地吸入液体，它不
仅具有较大的吸液能力，而且基本上消除了轴向推力。
(3)根据叶轮上叶片上的几何形状，可将叶片分为后弯、径向和前弯三种，由于后弯叶片有利于液体的动能转换为静压能，故而被广泛采用。
2．离心泵的导轮
为了减少离开叶轮的液体直接进入泵壳时因冲击而引起的能量损失，在叶轮与泵壳之间有时装置一个固定不动而带有叶片的导轮。导轮中的叶片使进入泵壳的液体逐渐转向而且流道连续扩大，使部分动能有效地转换为静压能。多级离心泵通常均安装导轮。
蜗牛形的泵壳、叶轮上的后弯叶片及导轮均能提高动能向静压能的转化率，故均可视作转能装置。
3．轴封装置
由于泵轴转动而泵壳固定不动，在轴和泵壳的接触处必然有一定间隙。为避免泵内高压液体沿间隙漏出，或防止外界空气从相反方向进入泵内，必须设置轴封装置。离心泵的轴封装置有填料函和机械（端面）密封。填料函是将泵轴穿过泵壳的环隙作成密封圈，于其中装入软填料（如浸油或涂石墨的石棉绳等）。机械密封是由一个装在转轴上的动环和另一固定在泵壳上的静环所构成。两环的端面借弹簧力互相贴紧而作相对转动，起到了密封的作用。机械密封适用于密封较高的场合，如输送酸、碱、易燃、易爆及有毒的液体。
（四）、离心泵的几条重要的性能曲线。
1、流量—扬程特性曲线
它是离心泵的基本的性能曲线。比转速小于80的离心泵具有上升和下降的特点（既中间凸起，两边下弯），称驼峰性能曲线。比转速在80～150之间的离心泵具有平坦的性能曲线。比转数在150以上的离心泵具有陡降性能曲线。一般的说，当流量小时，扬程就高，随着流量的增加扬程就逐渐下降。
2、流量—功率曲线
轴功率是随着流量而增加的，当流量Q=0时，相应的轴功率并不等于零，而为一定值（约正常运行的60％左右）。这个功率主要消耗于机械损失上。此时水泵里是充满水的，如果长时间的运行，会导致泵内温度不断升高，泵壳，轴承会发热，严重时可能使泵体热力变形，我们称为“闷水头”，此时扬程为最大值，当出水阀逐渐打开时，流量就会逐
渐增加，轴功率亦缓慢的增加。
3、流量—效率曲线
它的曲线象山头形状，当流量为零时，效率也等于零，随着流量的增大，效率也逐渐的增加，但增加到一定数值之后效率就下降了，效率有一个最高值，在最高效率点附近，效率都比较高，这个区域称为高效率区。
离心泵的型号说明 100KY100-200A 100--------吸入口直径（mm） KY--------水平中开式 100--------设计点流量（M3/h） 200--------设计点扬程（m） A-----------叶轮外径经第一次切割 本系列泵是单吸、多级、水平中开的卧式离心泵，供输送温度小于60℃的含水原油之用。主要用于油田内部集输工程，也可用于输送其他石油产品和清水。 制造泵的主要材质是铸铁、球墨铸铁和碳钢，根据用户要求，可选用硅黄铜、铝青铜、不锈钢等材料制造过流部位的零件。 IH50-32-160S1-303 IH-符合国际标准的化工泵
50-泵吸入口径（mm） 32-泵排出口径（mm） 160-叶轮名义直径（mm） S1-轴封形式（S1为单端内装型机械密封） 303-过流零件的材料代号（ZG1Cr18Ni9） IH系列泵是单级、单吸、悬臂式离心泵，是机械部确定取代F型离心泵的节能产品。适合于输送化工流程中有腐蚀性、粘度类似于水的液体。可广泛用于化工、石油、冶金、电力、造纸、食品、制药、合成纤维等行业。介质温度一般为-20℃～15℃，若采用适当的冷却措施，可输送更高温度的介质。 本系列泵共33个基本型，每种型号都可以通过切割叶轮获得较低的流量和扬程。 DYK DGK YD YDS型多级离心输液泵 DYK100-30*5
DYK--------- 100----------设计流量（M3/h） 30------------单级设计扬程（m） 5--------------级数 DYK、DGK、YD、YDS型泵适用于油田集输、厂矿企业排水和锅炉给水，输送介质为不带固体颗粒的原油、清水及物理、化学性质类似的液体，输送介质的温度低于105℃ 25CDLF2-260 25--------吸入口直径 CDL------轻型立式多级离心泵 F----------普通型略，过流部件为不锈钢304或316
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外文翻译 专业机械设计制造及其自动化学生姓名刘链柱 班级机制111 学号1110101102 指导教师葛友华
外文资料名称： Design and performance evaluation of vacuum cleaners using cyclone technology 外文资料出处：Korean J. Chem. Eng., 23(6), (用外文写) 925-930 (2006) 附件： 1.外文资料翻译译文 2.外文原文
应用旋风技术真空吸尘器的设计和性能介绍 吉尔泰金，洪城铱昌，宰瑾李， 刘链柱译 摘要：旋风型分离器技术用于真空吸尘器 - 轴向进流旋风和切向进气道流旋风有效地收集粉尘和降低压力降已被实验研究。优化设计等因素作为集尘效率，压降，并切成尺寸被粒度对应于分级收集的50％的效率进行了研究。颗粒切成大小降低入口面积，体直径，减小涡取景器直径的旋风。切向入口的双流量气旋具有良好的性能考虑的350毫米汞柱的低压降和为1.5μm的质量中位直径在1米3的流量的截止尺寸。一使用切向入口的双流量旋风吸尘器示出了势是一种有效的方法，用于收集在家庭中产生的粉尘。 摘要及关键词：吸尘器; 粉尘; 旋风分离器 引言 我们这个时代的很大一部分都花在了房子，工作场所，或其他建筑，因此，室内空间应该是既舒适情绪和卫生。但室内空气中含有超过室外空气因气密性的二次污染物，毒物，食品气味。这是通过使用产生在建筑中的新材料和设备。真空吸尘器为代表的家电去除有害物质从地板到地毯所用的商用真空吸尘器房子由纸过滤，预过滤器和排气过滤器通过洁净的空气排放到大气中。虽然真空吸尘器是方便在使用中，吸入压力下降说唱空转成比例地清洗的时间，以及纸过滤器也应定期更换，由于压力下降，气味和细菌通过纸过滤器内的残留粉尘。 图1示出了大气气溶胶的粒度分布通常是双峰形，在粗颗粒（>2.0微米）模式为主要的外部来源，如风吹尘，海盐喷雾，火山，从工厂直接排放和车辆废气排放，以及那些在细颗粒模式包括燃烧或光化学反应。表1显示模式，典型的大气航空的直径和质量浓度溶胶被许多研究者测量。精细模式在0.18?0.36 在5.7到25微米尺寸范围微米尺寸范围。质量浓度为2?205微克，可直接在大气气溶胶和 3.85至36.3μg/m3柴油气溶胶。
Optimum blank design of an automobile sub-frame Jong-Yop Kim a ,Naksoo Kim a,*,Man-Sung Huh b a Department of Mechanical Engineering,Sogang University,Shinsu-dong 1,Mapo-ku,Seoul 121-742,South Korea b Hwa-shin Corporation,Young-chun,Kyung-buk,770-140,South Korea Received 17July 1998 Abstract A roll-back method is proposed to predict the optimum initial blank shape in the sheet metal forming process.The method takes the difference between the ?nal deformed shape and the target contour shape into account.Based on the method,a computer program composed of a blank design module,an FE-analysis program and a mesh generation module is developed.The roll-back method is applied to the drawing of a square cup with the ˉange of uniform size around its periphery,to con?rm its validity.Good agreement is recognized between the numerical results and the published results for initial blank shape and thickness strain distribution.The optimum blank shapes for two parts of an automobile sub-frame are designed.Both the thickness distribution and the level of punch load are improved with the designed blank.Also,the method is applied to design the weld line in a tailor-welded blank.It is concluded that the roll-back method is an effective and convenient method for an optimum blank shape design.#2000Elsevier Science S.A.All rights reserved. Keywords:Blank design;Sheet metal forming;Finite element method;Roll-back method
化工离心泵条件及参数 一、化工离心泵的概述： 化工离心泵是单级单吸悬臂式离心泵，其标记性能点和尺寸等效采用国际标准 ISO2858-1975（E），是一种用以取代F型耐腐蚀泵更新换代的节能产品，适用于化工、石油、冶金、电站、食品、制药、合成纤维等部门输送温度在-20℃～105℃的腐蚀性介质或物理、氟塑料化工泵化学性能类似于水的介质。 二、化工离心泵的性能范围（按设计点）： 流量Q：6.3～400m3/h 扬程H：5～125m 泵的最高工作设计压力为1.6MPa 化工泵输送介质温度为-20℃～105℃，需要时采用双端面密封冷却装置，可输送介质温度为20℃～+280℃。耐腐蚀化工泵适用于化工、石油、冶金、电力、造纸、食品、制药、环保、废水处理和合成纤维等行业用于输送各种腐蚀的或不允许污染的类似于水的介质。 三、化工离心泵的性能范围： 流量Q：6.3～400m3/h扬程H：5～132m 转速n：2900、1450r/min配带功率：0.55～110KW 进口直径：50～200mm最高工作压力：1.6Mpa 系列泵有29个基本型，其中22个双速（2900、1450r/min）经过A、B两种型式的叶轮直径切割变型后，达112个规格。 泵的结构：
泵是全国泵行业采用ISO国际标准联合设计的系列产品，其主要由泵体、叶传输线、密封环、叶轮螺母、泵盖、密封部件、中间支架、轴、悬架部件等组成。 泵的结构特点： 化工泵盖通过止口固定在中间支架上，然后通过泵体与中间支架止口的联接把泵盖夹紧在中间，泵体是轴向吸入，径向排出，脚支承式，可直接固定在底座上。悬架部件通过止口固定固定在中间支架上，并用悬架支架支撑在底座上。为拆卸方便，设计了加长联轴器，检修时可以不拆卸进出口联接管路，泵体和电动机。只需拆下联轴器的中间联接件，即可退出转子部件进行检修。这是国际上通用的一种结构形式。 泵的旋转方向： 泵通过加长联轴器由电动机直接驱动，从电动机端看，按顺时针方向旋转。 泵的轴封型式：
外文翻译 原文 Foreign T rade o f China Material Source:W anfang Database Author:Hitomi Iizaka 1.Introduction On December11,2001,China officially joined the World T rade Organization(WTO)and be c a me its143rd member.China’s presence in the worl d economy will continue to grow and deepen.The foreign trade sector plays an important andmultifaceted role in China’s economic development.At the same time, China’s expanded role in the world economy is beneficial t o all its trading partners. Regions that trade with China benefit from cheaper and mor e varieties of imported consumer goods,raw materials and intermediate products.China is also a large and growing export market.While the entry of any major trading nation in the global trading system can create a process of adjustment,the o u t c o me is fundamentally a win-win situation.In this p aper we would like t o provide a survey of the various institutions,laws and characteristics of China’s trade.Among some of the findings, we can highlight thefollowing: ?In2001,total trade to gross domestic pr oduct(GDP)ratio in China is44% ?In2001,47%of Chinese trade is processed trade1 ?In2001,51%of Chinese trade is conduct ed by foreign firms in China2 ?In2001,36%of Chinese exports originate from Gu an gdon g province ?In2001,39%of China’s exports go through Hong Kong to be re-exported elsewhere 2.Evolution of China’s Trade Regime Equally remarkable are the changes in the commodity composition of China’s exports and imports.Table2a shows China’s annu al export volumes of primary goods and manufactured goods over time.In1980,primary goods accounted for 50.3%of China’s exports and manufactured goods accounted for49.7%.Although the share of primary good declines slightly during the first half of1980’s,it remains at50.6%in1985.Since then,exports of manufactured goods have grown at a much
化工泵参数及型号定义 上海阳光泵业作为国内一家著名的集研制、开发、生产、销售、服务于一体的大型多元化企业，上海阳光泵业制造有限公司一直坚持“以质量求生存、以品质求发展”的宗旨为广大客户提供优质服务!同时，上海阳光泵业一直专注于自身实力的提升以及对产品质量的严格把关，为此，目前不但拥有国内最高水准的水泵性能测试中心、完善的一体化服务体系、经验丰富的水泵专家，同时经过多年的发展，产品以优越的性能、精良的品质、良好的服务口碑获得各项专业认证证书和客户认可。经过团队的不懈努力，上海阳光泵业在国内水泵行业已经取得了很大成就。这样一家诚信为本、责任重于天的水泵行业佼佼者，对于水泵的维修、保养等各大方面都有自己独特的方法，下面就一起来看看吧! 一、ZX系列卧式自吸化工泵产品概述： ZX系列型泵是卧式自吸离心泵。耐腐蚀化工泵该型式泵与其它型式的自吸离心泵比较，因为泵本身没有逆止阀，结构最为简单；工作最为可靠；无故障工作时间长，维护、使用方便、体积小、重量轻、效率高、在设计上做了特别的考虑与相同口径的泵比较，排量大、性能高。 ZX型自吸泵在工农业生产、抢险救助，如排涝、救火中作为应急泵使用效能更为突出。氟塑料化工泵 ZX型泵广泛适用石油、化工、冶金、机械、化纤、食品、能源、交通等工业部门城市给水、亦可用于农业排灌、喷灌。供输送清水或粘度小于5°E，温度低于80℃物理及化学性质类似清水的其它液体。二、ZX系列卧式自吸化工泵技术参数： 流量：6.3～400m3/h； 扬程：5～132m； 转速：2900、1450r/min； 功率：0.55～110KW； 进口直径：50～200mm； 最高工作压力：1.6Mpa。 三、ZX系列卧式自吸化工泵维护和拆装：
GM in Petroleum & Chemical Industry 化工离心泵选型 上海尼可尼流体系统有限公司 （201100） 林 霞 西门子（中国）有限公司上海分公司 （200120） 陈 波
的离心泵，根据电动机驱动方式的不同，可以选择磁力泵、电动 机直联和屏蔽式。一般工程公司及设计院在前期设计时，多数已经确定了泵的形式，不需要另外选择和判断，但在某些类似案例重复出现的时候，也可以对泵的形式提出另外的建议。某化工企业项目在输送甲苯、乙苯、丙苯、苯乙烯、焦油、液化石油气及烷类介质的工位中要求使用无泄漏泵，客户考虑采用化工离心泵串联式干气密封，出于泵长期使用的安全性、易操作维护、减少现场管路布置等的考虑，建议用户选用磁力驱动泵，采用磁力驱动方式既可以达到介质无泄漏，又可以减少设置P L A N冲洗方案时的复杂管路配置，如提供外部供给阻隔气体用于干气密封的P L A N74配置。最终方案被采纳并顺利投入生产。某企业需要泵输送M T B E、异丁烯等介质，流量在1～3m 3/h之间，扬程在70～150m，客户考虑使用多级离心泵，根据旋涡泵的小流量高扬程、具有定量性、可通过变频调节流量的特点进行了推荐，而且旋涡泵比多级离心泵占地体积小、结构简单、适应急停急起运行，业主通过实际应用也对旋涡泵在该工况下的稳定性感到满意。 3.流量和扬程 无论对于化工离心泵还是普通水泵，对流量和扬程的选型基本原则都是相同的，即最大需要流量和最高需要扬程点落在最高效率点的左侧，一般在额定流量的30%～70%之间选型比较适合。在化工离心泵选型中，影响流量扬程点的因素有很多，主要为以下几种情况： （1）输送介质中含有微量细微颗粒时（固体粒径小于100μm） 普通离心泵的闭式叶轮结构就无法应对，一方面可以进行性能修正，扬程和效率比输送清水时的值下降同一个比例。另一方面，根据颗粒含量的多少及颗粒大小考虑将闭式叶轮改为半开式叶轮或开式叶轮，而这种叶轮形式的改变也将会影响泵在性能上的降低，在没有开式叶轮泵性能测试报告的时候，根据经验值可以按照5%～10%的性能下降比例来进行选型估算。 （2）介质为放射性危险液体、有毒有害液体或不允许泄漏物质时 磁力驱动离心泵起到了很好的密封作用，通过磁力驱动的化工离心泵与电动机直接驱动的化工离心泵，由于磁驱的作用泵性能也有所下降，根据选型经验一般按20%～25%考虑计算，泵选型配用的电动机功率也需要相应增加。 （3）离心泵输送介质为清水时 没有黏度因素影响泵的性能。但当介质黏度超过20cP（1cP=10－3Pa·s，下同）时，泵性能开始下降，例如泵输送清水介质时的性能为流量60m 3/h，扬程110m，当输送介质黏度为30c P时，性能下降为流量55.6m 3/h，扬程108m，当输送黏度为200c P的介质时，此泵的流量为40m 3/h，扬程为104m。化工离心泵选型建议输送介质的最大黏度范围在300c P以下，可以查表或用“黏性液体性能修正程序”来计算性能下降值。 旋涡泵的选型，由于其是全开式起动，靠出口阀门的调节控制吐出压力，与离心泵闭式起动，通过调节阀门控制流量的方法不同，所以在选型中，旋涡泵的主参考值是吐出压力，通过先查到性能曲线对应的压力点再查对应的流量点，与离心泵选型正好相反，两者的选型步骤分别如图1、图2所示。 图1 旋涡泵选型示意图 图2 离心泵选型示意图 所以旋涡泵选型可以不用遵照选型点在性能曲线最高效率点左侧这样的规则，由于旋涡泵流量越大功率越低，流量越小功率越高，所以只要在选型时注意，不要靠压力的过分增大来得到小流量即可，过高的压力值会增大电动机的负载，接近关死点的流量会使液体在泵 体流道内形成自循环，从而使液体的温度快速的升高，
翻译文献：INVESTIGATION ON DYNAMIC PERFORMANCE OF SLIDE UNIT IN MODULAR MACHINE TOOL （对组合机床滑台动态性能的调查报告） 文献作者：Peter Dransfield, 出处：Peter Dransfield, Hydraulic Control System-Design and Analysis of TheirDynamics, Springer-Verlag, 1981 翻译页数：p139—144 英文译文： 对组合机床滑台动态性能的调查报告 【摘要】这一张纸处理调查利用有束缚力的曲线图和状态空间分析法对组合机床滑台的滑动影响和运动平稳性问题进行分析与研究，从而建立了滑台的液压驱动系统一自调背压调速系统的动态数学模型。通过计算机数字仿真系统，分析了滑台产生滑动影响和运动不平稳的原因及主要影响因素。从那些中可以得出那样的结论，如果能合理地设计液压缸和自调背压调压阀的结构尺寸. 本文中所使用的符号如下： s1-流源，即调速阀出口流量； S el—滑台滑动摩擦力 R一滑台等效粘性摩擦系数： I1—滑台与油缸的质量 12—自调背压阀阀心质量 C1、c2—油缸无杆腔及有杆腔的液容； C2—自调背压阀弹簧柔度； R1, R2自调背压阀阻尼孔液阻， R9—自调背压阀阀口液阻 S e2—自调背压阀弹簧的初始预紧力； I4, I5—管路的等效液感 C5、C6—管路的等效液容： R5, R7-管路的等效液阻； V3, V4—油缸无杆腔及有杆腔内容积； P3, P4—油缸无杆腔及有杆腔的压力 F—滑台承受负载， V—滑台运动速度。本文采用功率键合图和状态空间分折法建立系统的运动数学模型，滑台的动态特性可以能得到显著改善。
204/JOURNAL OF BRIDGE ENGINEERING/AUGUST1999
JOURNAL OF BRIDGE ENGINEERING /AUGUST 1999/205 ends.The stress state in each cylindrical strip was determined from the total potential energy of a nonlinear arch model using the Rayleigh-Ritz method. It was emphasized that the membrane stresses in the com-pression region of the curved models were less than those predicted by linear theory and that there was an accompanying increase in ?ange resultant force.The maximum web bending stress was shown to occur at 0.20h from the compression ?ange for the simple support stiffness condition and 0.24h for the ?xed condition,where h is the height of the analytical panel.It was noted that 0.20h would be the optimum position for longitudinal stiffeners in curved girders,which is the same as for straight girders based on stability requirements.From the ?xed condition cases it was determined that there was no signi?cant change in the membrane stresses (from free to ?xed)but that there was a signi?cant effect on the web bend-ing stresses.Numerical results were generated for the reduc-tion in effective moment required to produce initial yield in the ?anges based on curvature and web slenderness for a panel aspect ratio of 1.0and a web-to-?ange area ratio of 2.0.From the results,a maximum reduction of about 13%was noted for a /R =0.167and about 8%for a /R =0.10(h /t w =150),both of which would correspond to extreme curvature,where a is the length of the analytical panel (modeling the distance be-tween transverse stiffeners)and R is the radius of curvature.To apply the parametric results to developing design criteria for practical curved girders,the de?ections and web bending stresses that would occur for girders with a curvature corre-sponding to the initial imperfection out-of-?atness limit of D /120was used.It was noted that,for a panel with an aspect ratio of 1.0,this would correspond to a curvature of a /R =0.067.The values of moment reduction using this approach were compared with those presented by Basler (Basler and Thurlimann 1961;Vincent 1969).Numerical results based on this limit were generated,and the following web-slenderness requirement was derived: 2 D 36,500a a =1?8.6?34 (1) ? ??? t R R F w ?y where D =unsupported distance between ?anges;and F y =yield stress in psi. An extension of this work was published a year later,when Culver et al.(1973)checked the accuracy of the isolated elas-tically supported cylindrical strips by treating the panel as a unit two-way shell rather than as individual strips.The ?ange/web boundaries were modeled as ?xed,and the boundaries at the transverse stiffeners were modeled as ?xed and simple.Longitudinal stiffeners were modeled with moments of inertias as multiples of the AASHO (Standard 1969)values for straight https://www.doczj.com/doc/192186272.html,ing analytical results obtained for the slenderness required to limit the plate bending stresses in the curved panel to those of a ?at panel with the maximum allowed out-of-?atness (a /R =0.067)and with D /t w =330,the following equa-tion was developed for curved plate girder web slenderness with one longitudinal stiffener: D 46,000a a =1?2.9 ?2.2 (2) ? ? ? t R f R w ?b where the calculated bending stress,f b ,is in psi.It was further concluded that if longitudinal stiffeners are located in both the tension and compression regions,the reduction in D /t w will not be required.For the case of two stiffeners,web bending in both regions is reduced and the web slenderness could be de-signed as a straight girder panel.Eq.(1)is currently used in the ‘‘Load Factor Design’’portion of the Guide Speci?cations ,and (2)is used in the ‘‘Allowable Stress Design’’portion for girders stiffened with one longitudinal stiffener.This work was continued by Mariani et al.(1973),where the optimum trans-verse stiffener rigidity was determined analytically. During almost the same time,Abdel-Sayed (1973)studied the prebuckling and elastic buckling behavior of curved web panels and proposed approximate conservative equations for estimating the critical load under pure normal loading (stress),pure shear,and combined normal and shear loading.The linear theory of shells was used.The panel was simply supported along all four edges with no torsional rigidity of the ?anges provided.The transverse stiffeners were therefore assumed to be rigid in their directions (no strains could be developed along the edges of the panels).The Galerkin method was used to solve the governing differential equations,and minimum eigenvalues of the critical load were calculated and presented for a wide range of loading conditions (bedding,shear,and combined),aspect ratios,and curvatures.For all cases,it was demonstrated that the critical load is higher for curved panels over the comparable ?at panel and increases with an increase in curvature. In 1980,Daniels et al.summarized the Lehigh University ?ve-year experimental research program on the fatigue behav-ior of horizontally curved bridges and concluded that the slen-derness limits suggested by Culver were too severe.Equations for ‘‘Load Factor Design’’and for ‘‘Allowable Stress Design’’were developed (respectively)as D 36,500a =1?4?192(3)? ?t R F w ?y D 23,000a =1?4 ?170 (4) ? ? t R f w ?b The latter equation is currently used in the ‘‘Allowable Stress Design’’portion of the Guide Speci?cations for girders not stiffened longitudinally. Numerous analytical and experimental works on the subject have also been published by Japanese researchers since the end of the CURT project.Mikami and colleagues presented work in Japanese journals (Mikami et al.1980;Mikami and Furunishi 1981)and later in the ASCE Journal of Engineering Mechanics (Mikami and Furunishi 1984)on the nonlinear be-havior of cylindrical web panels under bending and combined bending and shear.They analyzed the cylindrical panels based on Washizu’s (1975)nonlinear theory of shells.The governing nonlinear differential equations were solved numerically by the ?nite-difference method.Simple support boundary condi-tions were assumed along the curved boundaries (top and bot-tom at the ?ange locations)and both simple and ?xed support conditions were used at the straight (vertical)boundaries.The large displacement behavior was demonstrated by Mi-kami and Furunishi for a range of geometric properties.Nu-merical values of the load,de?ection,membrane stress,bend-ing stress,and torsional stress were obtained,but no equations for design use were presented.Signi?cant conclusions include that:(1)the compressive membrane stress in the circumfer-ential direction decreases with an increase in curvature;(2)the panel under combined bending and shear exhibits a lower level of the circumferential membrane stress as compared with the panel under pure bending,and as a result,the bending moment carried by the web panel is reduced;and (3)the plate bending stress under combined bending and shear is larger than that under pure bending.No formulations or recommendations for direct design use were made. Kuranishi and Hiwatashi (1981,1983)used the ?nite-ele-ment method to demonstrate the elastic ?nite displacement be-havior of curved I-girder webs under bending using models with and without ?ange rigidities.Rotation was not allowed (?xed condition)about the vertical axis at the ends of the panel (transverse stiffener locations).Again,the nonlinear distribu-
提高塔式复合人工湿地处理农村生活污水的 脱氮效率1 摘要： 努力保护水源，尤其是在乡镇地区的饮用水源，是中国污水处理当前面临的主要问题。氮元素在水体富营养化和对水生物的潜在毒害方面的重要作用，目前废水脱氮已成为首要关注的焦点。人工湿地作为一种小型的，处理费用较低的方法被用于处理乡镇生活污水。比起活性炭在脱氮方面显示出的广阔前景，人工湿地系统由于溶解氧的缺乏而在脱氮方面存在一定的制约。为了提高脱氮效率，一种新型三阶段塔式混合湿地结构----人工湿地（thcw）应运而生。它的第一部分和第三部分是水平流矩形湿地结构，第二部分分三层，呈圆形，呈紊流状态。塔式结构中水流由顶层进入第二层及底层，形成瀑布溢流，因此水中溶解氧浓度增加，从而提高了硝化反应效率，反硝化效率也由于有另外的有机物的加入而得到了改善，增加反硝化速率的另一个原因是直接通过旁路进入第二部分的废水中带入的足量有机物。常绿植物池柏（Taxodium ascendens），经济作物蔺草（Schoenoplectus trigueter），野茭白（Zizania aquatica），有装饰性的多花植物睡莲（Nymphaea tetragona），香蒲（Typha angustifolia）被种植在湿地中。该系统对总悬浮物、化学需氧量、氨氮、总氮和总磷的去除率分别为89%、85%、83%、83% 和64%。高水力负荷和低水力负荷（16 cm/d 和32 cm/d）对于塔式复合人工湿地结构的性能没有显著的影响。通过硝化活性和硝化速率的测定，发现硝化和反硝化是湿地脱氮的主要机理。塔式复合人工湿地结构同样具有观赏的价值。 关键词： 人工湿地；硝化作用；反硝化作用；生活污水；脱氮；硝化细菌；反硝化细菌 １. 前言 对于提高水源水质的广泛需求，尤其是提高饮用水水源水质的需求是目前废水深度处理的技术发展指向。在中国的乡镇地区，生活污水是直接排入湖泊、河流、土壤、海洋等水源中。这些缺乏处理的污水排放对于很多水库、湖泊不能达到水质标准是有责任的。许多位于中国的乡镇地区的社区缺乏足够的生活污水处理设备。由于山区地形、人口分散、经济基础差等原因，废水的收集和处理是很成问题的。由于资源短缺，经济欠发达地区所采取的废水处理技术必须低价高效，并且要便于施用，能量输入及维护费用较低，而且要保证出水能达标。建造在城市中基于活性污泥床的废水集中处理厂，对于小乡镇缺乏经济适用性，主要是由于污水收集结构的建造费用高。 1Ecological Engineering，Fen xia ，Ying Li。
泵型号各字母代表的意思 The Standardization Office was revised on the afternoon of December 13, 2020
B: 单级单吸悬臂式离心泵。 D: 节段式多级泵。 DG: 节段式多级锅炉给水泵。 DL: 立轴多级泵。 DS: 首级用双吸叶轮的节段式多级泵。 F: 耐腐蚀泵。 JC: 长轴深井泵。 KD: 中开式多级泵。 KDS: 首级用双吸叶轮的中开式多级泵。 QJ: 井用潜水泵。 QX.: 单相干式下泵式潜水泵。 QS: 充水上泵式潜水泵。 QY: 充油上泵式潜水泵。 R: 热水泵。 S: 单级双吸式离心泵。 WB: 高扬程横轴污水泵。 Y: 液压泵。 YG: 管道式液压泵。 ZB: 自吸式离心泵。 目前离心泵产品型号一共有32种，分别是：SG管道离心泵、 ISW卧式管道离心泵、
QDLF不锈钢多级离心泵、GC锅炉给水离心泵、 DL立式多级离心泵、GDL多级管道离心泵、PBG屏蔽式管道离心泵、YG立式管道油泵、ISWR卧式热水泵、ISWH卧式化工泵 ISWB卧式管道油泵、ISG立式管道离心泵、IRG立式热水循环泵、IHG立式管道化工泵、ISGB便拆式管道离心泵ISGD低转速离心泵、ISWD低转速离心泵、 IS单级单吸清水离心泵、IH单级单吸化工离心泵、FS卧式玻璃钢离心泵、 S型玻璃钢离心泵、GBW浓硫酸离心泵、FSB型氟塑料合金离心泵、AFB、FB耐腐蚀离心泵、
TSWA卧式多级离心泵 、ZX自吸式离心泵、 S、Sh单级双吸离心泵、 LG高层建筑给水多级离心泵、 CDLF不锈钢立式多级离心泵、 D多级离心泵、 CYZ-A自吸式离心泵、 IHF氟塑料合金化工离心泵。 油泵的型号及技术参数 AY型离心油泵：流量Q ～500m3/h 扬程H 60～300m AY型系列离心油泵可用在石油精致、石油化工和化学工业及其它输送不含固体颗粒的石油、液化石油气等介质。 DY型多级离心泵：流量Q 10～540m3/s 扬程H 87～690m