Unit14 limits and tolerances

Unit1Two methods of designating limit dimensions are considered as standard.One method is the maximum material method in which the large dimension is placed above the smaller dimension for male parts, and the reverse is true for female parts.This method is well suited for small lot quantities because it is likely that the machinist himself may check the dimension of the parts .In so doing he will be verifying initially the large dimension of the male parts and the smaller dimension of the female part.other method is the maximum number method and is preferred by production and quality control departments .In this method of designating a dimension , the large number is always placed above the smaller number ,regardless of whether the part is male or female.两种方法都被看作是指定极限尺寸标准。

一种方法是最大的资料法,大尺寸较小的尺寸摆在上面男性部件,事实正相反对女性的部分。

英文：Engineering ToleranceIntroductionA solid is defined by its surface boundaries. Designers typically specify a component’s nominal dimensions such that it fulfils its requirements. In reality, components cannot be made repeatedly to nominal dimensions, due to surface irregularities and the intrinsic surface roughness. Some variability in dimensions must be allowed to ensure manufacture is possible. However, the variability permitted must not be so great that the performance of the assembled parts is impaired. The allowed variability on the individual component dimensions is called the tolerance.The term tolerance applies not only to the acceptable range of component dimensions produced by manufacturing techniques, but also to the output of machines or processes. For example , the power produced by a given type of internal combustion engine varies from one engine to another. In practice, the variability is usually found to be modeled by a frequency distribution curve, for example the normal distribution (also called the Gaussian distribution).One of the tasks of the designer is to specify a dimension on a component and the allowable variability on this value that will give acceptable performance.Component TolerancesControl of dimensions is necessary in order to ensure assembly and interchangeability of components. Tolerances are specified on critical dimensions that affect clearances and interferences fits. One method of specifying tolerances is to state the nominal dimension followed by the permissible variation, so a dimension could be stated as 40.000mm ± 0.003mm.This means that the dimension should be machined so that it is between 39.997mm and 40.003mm.Where thevariation can vary either side of the nominal dimension, the tolerance is called a bilateral tolerance. For a unilateral tolerance, one tolerance is zero, e.g. 40+0.006 .0.000Most organizations have general tolerances that apply to dimensions when an explicit dimension is not specified on a drawing. For machined dimensions a general tolerance may be ±0.5mm. So a dimension specified as 15.0mm may range between 14.5mm and 15.5mm. Other general tolerances can be applied to features such as angles, drilled and punched holes, castings，forgings, weld beads and fillets.When specifying a tolerance for a component, reference can be made to previous drawings or general engineering practice. Tolerances are typically specified in bands as defined in British or ISO standards.Standard Fits for Holes and ShaftsA standard engineering ask is to determine tolerances for a cylindrical component, e.g. a shaft, fitting or rotating inside a corresponding cylindrical component or hole. The tightness of fit will depend on the application. For example, a gear located onto a shaft would require a “tight” interference fit, where the diameter of the shaft is actually slightly greater than the inside diameter of the gear hub in order to be able to transmit the desired torque. Alternatively, the diameter of a journal bearing must be greater than the diameter of the shaft to allow rotation. Given that it is not economically possible to manufacture components to exact dimensions, some variability in sizes of both the shaft and hole dimension must be specified. However, the range of variability should not be so large that the operation of the assembly is impaired. Rather than having an infinite variety of tolerance dimensions that could be specified, national and international standards have been produced defining bands of tolerances. To turn this information into actual dimensions corresponding tables exist，defining the tolerance levels for the size of dimension under consideration.Size：a number expressing in a particular unit the numerical value of a dimension.Actual size：the size of a part as obtained by measurement.Limits of size：the maximum and minimum sizes permitted for a feature.Maximum limit of size the greater of the two limits of size.Minimum limit of size：the smaller of the two limits of size.Basic size：the size by reference to which the limits of size are fixed.Deviation：the algebraic difference between a size and the corresponding basic size.Actual deviation：the algebraic difference between the actual size and the corresponding basic size.Upper deviation：the algebraic difference between the maximum limit of size and the corresponding basic size.Lower deviation：the algebraic difference between the minimum limit of size and the corresponding basic size.Tolerance：the difference between the maximum limit of size and the minimum limit of size.Shaft：the term used by convention to designate all external features of a part.Hole：the term used by convention to designate all internal features of a part.Heat Treatment of MetalThe generally accepted definition for heat treating metals and metal alloys is “heating and cooling a solid metal or alloy in a way so as to obtain specific conditions and I or properties.”Heating for the sole purpose of hot working(as in forging operations) is excluded from this definition．Likewise，the types of heat treatment that are sometimes used for products such as glass or plastics are also excluded from coverage by this definition．Transformation CurvesThe basis for heat treatment is the time-temperature-transformation curves or TTT curves where，in a single diagram all the three parameters are plotted．Becauseof the shape of the curves，they are also sometimes called C-curves or S-curves．To plot TTT curves，the particular steel is held at a given temperature and the structure is examined at predetermined intervals to record the amount of transformation taken place．It is known that the eutectoid steel (T80) under equilibrium conditions contains，all austenite above 723℃，whereas below，it is pearlite．To form pearlite，the carbon atoms should diffuse to form cementite．The diffusion being a rate process，would require sufficient time for complete transformation of austenite to pearlite ．From different samples，it is possible to note the amount of the transformation taking place at any temperature．These points are then plotted on a graph with time and temperature as the axes．Classification of Heat Treating ProcessesIn some instances，heat treatment procedures are clear cut in terms of technique and application．whereas in other instances，descriptions or simple explanations are insufficient because the same technique frequently may be used to obtain different objectives ．For example, stress relieving and tempering are often accomplished with the same equipment and by use of identical time and temperature cycles．The objectives，however，are different for the two processes ．The following descriptions of the principal heat treating processes are generally arranged according to their interrelationships．Normalizing consists of heating a ferrous alloy to a suitable temperature (usually 50°F to 100 °F or 28 ℃to 56℃) above its specific upper transformation temperature. This is followed by cooling in still air to at least some temperature well below its transformation temperature range．For low-carbon steels．the resulting structure and properties are the same as those achieved by full annealing ；for most ferrous alloys, normalizing and annealing are not synonymous.Normalizing usually is used as a conditioning treatment, notably for refining the grain of steels that have been subjected to high temperatures for forging or other hot working operations．The normalizing process usually is succeededby another heat treating operation such as austenitizing for hardening, annealing，or tempering.Annealing is a generic term denoting a heat treatment that consists of heating to and holding at a suitable temperature followed by cooling at a suitable rate．It is used primarily to soften metallic materials，but also to simultaneously produce desired changes in other properties or in microstructure．The purpose of such changes may be，but is not confined to, improvement of machinability, facilitation of cold work ( known as in-process annealing)，improvement of mechanical or electrical properties, or to increase dimensional stability．When applied solely to relieve stresses, it commonly is called stress-relief annealing, synonymous with stress relieving．When the term “anneali ng is applied to ferrous alloys without qualification, full annealing is implied．This is achieved by heating above the alloy’s transformation temperature，then applying a cooling cycle which provides maximum softness．This cycle may vary widely, depending on composition and characteristics of the specific alloy．Quenching is the rapid cooling of a steel or alloy from the austenitizing temperature by immersing the workpiece in a liquid or gaseous medium．Quenching media commonly used include water，5% brine，5% caustic in an aqueous solution，oil，polymer solutions，or gas(usually air or nitrogen)．Selection of a quenching medium depends largely on the hardenability of the material and the mass of the material being treated(principally section thickness)．The cooling capabilities ofthe above-listed quenching media vary greatly．In selecting a quenching medium, it is best to avoid a solution that has more cooling power than is needed to achieve the results，thus minimizing the possibility of cracking and warp of the parts being treated．Modifications of the term quenching include direct quenching，fog quenching，hot quenching，interrupted quenching selective quenching，spray quenching, and time quenching．Tempering ．In heat treating of ferrous alloys ，tempering consists of reheating the austenitized and quench-hardened steel or iron to some preselected temperature that is below the lower transformation temperature (generally below 1300°F or 705℃) ．Tempering offers a means of obtaining various combinations of mechanical properties．Tempering temperatures used for hardened steels are often no higher than 300°F (150℃)．The term “tempering”should not be confused with either process annealing or stress relieving．Even though time and temperature cycles for the three processes may be the same，the conditions of the materials being processed and the objectives may be different．Stress Relieving．Like tempering, stress relieving is always done by heating to some temperature below the lower transformation temperature for steels and irons ．For nonferrous metals，the temperature may vary from slightly above room temperature to several hundred degrees，depending on the alloy and the amount of stress relief that is desired．The primary purpose of stress relieving is to relieve stresses that have been imparted to the workpiece from such processes as forming, rolling，machining or welding．The usual procedure is to heat workpieces to the pre-established temperature long enough to reduce the residual stresses (this is a time-and temperature-dependent operation) to an acceptable level；this is followed by cooling at a relatively slow rate to avoid creation of new stresses．Introduction to CAD/CAMThroughout the history of our industrial society, many inventions have been patented and whole new technologies have evolved. Perhaps the single development that has impacted manufacturing more quickly and significantly than any previous technology is the digital computer. Computers are being used increasingly for both design and detailing of engineering components in the drawing office.Computer-aided design (CAD) is defined as the application of computers and graphics software to aid or enhance the product design from conceptualizationto documentation. CAD is most commonly associated with the use of an interactive computer graphics system, referred to as a CAD system. Computer-aided design systems are powerful tools and are used in the mechanical design and geometric modeling of products and components.There are several good reasons for using a CAD system to support the engineering design function：⑴To increase the productivity⑵To improve the quality of the design⑶To uniform design standards⑷To create a manufacturing data base⑸To eliminate inaccuracies caused by hand-copying of drawingsand inconsistency between drawingsComputer-aided manufacturing (CAM) is defined as the effective use of computer technology in manufacturing planning and control. CAM is most closely associated with functions in manufacturing engineering, such as process and production planning, machining, scheduling, management, quality control, and numerical control (NC) part programming. Computer-aided design and computer-aided manufacturing are often combined into CAD/CAM systems.This combination allows the transfer of information from the design stage into the stage of planning for the manufacturing of a product, without the need to reenter the data on part geometry manually. The database developed during CAD is stored; then it is processed further, by CAM, into the necessary data and instructions for operating an controlling production machinery, material-handling equipment, and automated testing and inspection for product quality.Rationale for CAD/CAMThe rationale for CAD/CAM is similar to that used to justify any technology-based improvement in manufacturing. It grows out of a need to continually improve productivity, quality and competitiveness. There are also other reasons why a company might make a conversion from manual processes toCAD/CAM：⑴Increased productivity⑵Better quality⑶Better communication⑷Common database with manufacturing⑸Reduced prototype construction costs⑹Faster response to customersCAD/CAM HardwareThe hardware part of a CAD/CAM system consists of the following components：(1) one or more design workstations,(2) digital computer, (3) plotters, printers and other output devices, and (4) storage devices. In addition, the CAD/CAM system would have a communication interface to permit transmission of data to and from other computer systems, thus enabling some of the benefits of computer integration.The workstation is the interface between computer and user in the CAD system. The design of the CAD workstation and its available features have an important influence on the convenience, productivity, and quality of the user’s output. The workstation must include a graphics display terminal and a set of user input devices. CAD/CAM applications require a digital computer with a high-speed control processing unit (CPU). It contains the main memory and logic/arithmetic section for the system. The most widely used secondary storage medium in CAD/CAM is the hard disk, floppy diskette, or a combination of both.Input devices are generally used to transfer information from a human or storage medium to a computer where “CAD functions” are carried out. There are two basic approaches to input an existing drawing:model the object on a drawing or digitize the drawing. The standard output device for CAD/CAM is a CRT display. There are two major types of CRT displays: random-scan-line-drawing displays and raster-scan displays. In addition to CRT, there are also plasma paneldisplays and liquid-crystal displays.CAD/CAM SoftwareSoftware allows the human user to turn a hardware configuration into a powerful design and manufacturing system. CAD/CAM software falls into two broad categories, 2-D and 3-D, based on the number of dimensions visible in the finished geometry. CAD packages that represent objects in two dimensions are called 2-D software. Early systems were limited to 2-D. This was a serious shortcoming because 2-Drepresentations of 3-Dobjects is inherently confusing. Equally problem has been the inability of manufacturing personnel to properly read and interpret complicated 2-D representations of objects. 3-D software permits the parts to be viewed with the three-dimensional planes-height, width, and depth-visible. The trend in CAD/CAM is toward 3-D representation of graphic images. Such representations approximate the actual shape and appearance of the object to be produced; therefore, they are easier to read and understand.Applications of CAD/CAMThe emergence of CAD/CAM has had a major impact on manufacturing, by standardizing product development and by reducing design effort, tryout, and prototype work; it has made possible significantly reduced costs and improved productivity.Numerical ControlNumerical control (NC) is a form of programmable automation in which the processing equipment is controlled by means of numbers，letters，and other symbols．The numbers，letters，and symbols are coded in an appropriate format to define a program of instructions for a particular workpart or job. Theinstructions are provided by either of the two binary coded decimal systems: the Electronic Industries Association (EIA) code, or the American Standard Code for Information Interchange (ASCII). ASCII-coded machine control units will not accept EIA coded instructions and vice versa. Increasingly, however, control units are being made to accept instructions in either code. Automation operation by NC is readily adaptable to the operation of all metalworking machines. Lathes, milling machines, drill presses, boring machines, grinding machines, turret punches, flame or wire-cutting and welding machines, and even pipe benders are available with numerical controls.Basic Components of NCA numerical control system consists of the following three basic components：(1) Program instructions(2) Machine control unit(3) Processing equipmentThe program instructions are the detailed step by step commands that direct the processing equipment In its most common form，the commands refer to positions of a machine tool spindle with respect to the worktable on which the part is fixed．More advanced instructions include selection of spindle speeds，cutting tools，and other functions.The machine control unit (MCU) consists of the electronics and control hardware that reads and interprets the program of instructions and convert it into mechanical actions of the machine tool or other processing equipment ．The processing equipment is the component that performs metal process．In the most common example of numerical control ，it is used to perform machining operations. The processing equipment consists of the worktable and spindle as well as the motors and controls needed to drive them．Types of NCThere are two basic types of numerical control systems：point to point and contouring ．Point to point control system, also called positioning, are simpler than contouring control system．Its primary purpose is to move a tool or workpiece from one programmed point to another. Usually the machine function，such as a drilling operation，is also activated at each point by command from the NC Program．Point to point systems are suitable for hole machining operations such as drilling, countersinking，counterboring，reaming，boring and tapping. Hole punching machines，spotwelding machines，and assembly machines also use point to point NC systems．Contouring system，also known as the continuous path system，positioning and cutting operations are both along controlled paths but at different velocities．Because the tool cuts as it travels along a prescribed path ，accurate control and synchronization of velocities and movements are important．The contouring system is used on lathes，milling machines，grinders，welding machinery，and machining centers．Movement along the path，or interpolation, occurs incrementally，by one of several basic methods ．There are a number of interpolation schemes that have been developed to deal with the various problems that are encountered in generating a smooth continuous path with a contouring type NC system．They include linear interpolation, circular interpolation, helical interpolation, parabolic interpolation and cubic interpolation. In all interpolations，the path controlled is that of the center of rotation of the tool．Compensation for different tools，different diameter tools，or tools wear during machining，can be made in the NC program．Programming for NCA program for numerical control consists of a sequence of directions that causes an NC machine to carry out a certain operation ，machining being the most commonly used process ．Programming for NC may be done by aninternal programming department，on the shop floor，or purchased from an outside source．Also，programming may be done manually or with computer assistance．The program contains instructions and commands．Geometric instructions pertain to relative movements between the tool and the workpiece. Processing instructions pertain to spindle speeds，feeds，tools，and so on．Travel instructions pertain to the type of interpolation and slow or rapid movements of the tool or worktable．Switching commands pertain to on/off position for coolant supplies，spindle rotation，direction of spindle rotation tool changes，workpiece feeding，clamping，and so on. The first NC programming language was developed by MIT developmental work on NC programming systems in the late 1950s and called APT(Automatically Programmed Tools).DNC and CNCThe development of numerical control was a significant achievement in batch and job shop manufacturing，from both a technological and a commercial viewpoint．There have been two enhancements and extensions of NC technology，including：(1) Direct numerical control(2) Computer numerical controlDirect numerical control can be defined as a manufacturing system in which a number of machines are controlled by a computer through direct connection and in real time．The tape reader is omitted in DNC，thus relieving the system of its least reliable component．Instead of using the tape reader，the part program is transmitted to the machine tool directly from the computer memory．In principle，one computer can be used to control more than 100 separate machines．(One commercial DNC system during the l970s boasted a control capability of up to 256 machine tools.) The DNC computer is designed to provide instructions to each machine tool on demand ．When the machine needs control commands ，they are communicated to it immediately．Since the introduction of DNC ，there have been dramatic advances in computer technology．The physical size and cost of a digital computer has been significantly reduced at the same time that its computational capabilities have been substantially increased．In numerical control，the result of these advances has been that the large hard-wired MCUs of conventional NC have been replaced by control units based on the digital computer．Initially，minicomputers were utilized in the early 1970s ．As further miniaturization occurred in computers ，minicomputers were replaced by today’s microcomputers．Computer numerical control is an NC system using dedicated microcomputer as the machine control unit ．Because a digital computer is used in both CNC and DNC，it is appropriate to distinguish between the two types of system．There are three principal differences：(1) DNC computers distribute instructional data to，and collect data from， a large number of machines．CNC computers control only one machine，or a small number of machines．(2) DNC computers occupy a location that is typically remote from the machines under their control. CNC computer are located very near their machine tools.(3) DNC software is developed not only to control individual pieces of production equipment, but also to serve as part of a management information system in the manufacturing sector of the firm. CNC software is developed to augment the capabilities of a particular machine tool.中文翻译：工程公差引言固体由其表面边界确定界限。

Get familiar with the words and expressions listed below, and then complete each of the following sentences with a proper word from the list.多孔的，漏洞多的骨质减少鉴定，识别密度，浓度生育，分娩双膦酸盐类药物阿仑膦酸钠片碳酸钙伊班膦酸钠片甲状旁腺素骨折，破裂骨裂粉碎性骨折弓形骨折绿枝性骨折复合骨折头昏眼花的使人眩晕的，引起头晕的威胁生命的金属固定板固定用敷料，石膏夹板筛查最初的，开始的老年保健医疗更年期，绝经期重申反复灌输关键的，决定性的限额，折扣自体免疫的不确定的，不能使人信服的矛盾的不足的，缺乏的大剂量著名的，杰出的，突出的适当的，恰当的肾结石1.Autoimmune disorders are conditions in which a person’s immune system attack s the body’s own cells, causing tissue destruction.2. A fracture usually results from traumatic injury to a bone, causing thecontinuity of bone tissues or bony cartilage to be disrupted or broken.3. The government should be playing a more prominent role in healthpromotion.4. I keep getting contradictory advice - some people tell me to keep itwarm and some tell me to put ice on it.5. If he doesn’t eat something at lunchtime he will start to feel lightheaded by mid-afternoon.6. Initial reports say that seven people have died, though this has not yetbeen confirmed.7. A diet deficient in vitamin D may cause the disease rickets.8. A life-threatening disease is a very serious one that can cause death.9. Identification of osteoporosis and osteopenia is made by measuring the mineral density of a person’s bones.10. Doctors urge more older women to be screened for osteoporosis.11. A bone density test done on older women measures the risk ofgetting osteoporosis.12. The medical tests were inconclusive, and will need to be repeated.13. The baggage allowance for most flights is 20 kilos.14. The survey is only concerned with women of childbearing age.15. Modern scientific techniques have made it possible for a womanpast menopause to have a baby.Write down three questions you find interesting to explore on the topic “Bone Health”. The first two questions are given as a prompt. Discuss brieflyeach of them with your deskmates.1. What major functions do our bones have?2. What risk factors affect bone health?3. _______________________________________________4. _______________________________________________5. _______________________________________________Listen to a passage three times and while listening, you are to put the missing word in each numbered blank according to what you hear.The word osteoporosis means porous bones, or bones that are not (1) solid enough. The disease harms bones by removing calcium and other (2) minerals from tissue. The National Osteoporosis Foundation says eight of every ten osteoporosis patients are women.Before people (3) develop osteoporosis, they have a condition called osteopenia. Treatment can (4) prevent this condition from becoming osteoporosis. Doctors agree that the best way to deal with osteopenia or osteoporosis is to find and treat it before the disease (5) progresses. Bone damage need not be permanent. Drugs can help replace lost bone.(6) Identification of osteoporosis and osteopenia is made by measuring the mineral density of a person’s bones. In this ca se, density means the (7) strength of the bones.Differences in bone mineral density among body parts are most often found in women who recently ended their (8) childbearing years. The density may be normal at one place but low at another. Bone mineral density in the (9) spine decreases first. A woman’s bone mineral density becomes about the same in all parts of her body after she is 70 years old.Doctors who treat osteoporosis patients say physical exercise can help the bones. For active people, (10)lifting weights or playing tennis, slow running and dancing can be helpful.Several kinds of drugs treat osteoporosis. America’s Mayo Clinic medical centers say bisphosphonates are the most popular. Fosamax, Actonel and Boniva are (11) products of this family of drugs. The Mayo Clinic advises that these drugs are very effective and appear safe for most people if taken as (12) directed.Listen to a passage “Fracture” twice. While listening, you are to give an answer as short as possible to each of the questions below.1. What kind of fracture is it when a bone is broken in more than two places?A comminuted fracture.2. What kind of fracture is it when the bone breaks the skin?An open or compound fracture.3. What happens to people if they are seriously injured?People can go into shock.4. Why should broken bones be treated quickly?They can restrict blood flow or cause nerve damage.5. Why in some cases is a splint, instead of casts, put around the area of the break?To restrict movement.Listen to each sentence, repeat it aloud, listen to it again, and then write down the whole sentence on the space provided. You will listen to each sentence for a third time to have a check.1. Along with the bone damage there is a risk of infection in the openwound.2. While broken bones can be painful, they are generally not life-threatening.3. People who are seriously injured can go into shock. They might feel cold, dizzy and unable to think clearly.4. Broken bones should be treated quickly because they can restrict blood flow or cause nerve damage.5. X-rays are taken to see the break. Treatment depends on the kind of fracture that is identified.Watch a video clip “Bone Density Test” twice and decide whether each of the statements below is TRUE (T) or FALSE(F)._T_ _T_ _F_ _F_ 1. Osteoporosis is the hidden danger that millions of women face as they age.2. A bone density test measures the risk of gettingosteoporosis.3. According to a new study, women with healthy bones need to be tested as often as they have been.4. Dr. Ethel Cyrus emphasizes the importance ofgetting a bone density test every year after theage of 65._F__T_ _F_ 5. The bone starts to thin after menopause aroundage 50 so it is worth the money to test most women at this age. 6. A good thing to do for bone health is getting enough calcium.7. Frequent follow-up scans can be dangerous forwomen with thinning bones.Watch a video clip “Bone Health and Calcium Supplements” twice and choose the best answer to each of the questions below.1. Which of the following statement is TRUE of a new report from theInstitute of Medicine?A) It says women need more calcium to keep their bones healthy.B) It says much of what has been told about vitamin D is a myth.C) It has been hammered into ma ny healthy women’s heads.D) It says women need more vitamin D rather than calcium.2. The report holds a surprise that _______.A) calcium is added to everythingB) there is no debate over vitamin DC) both calcium and vitamin D are criticalD) many peop le don’t need calcium supplements3. It is mentioned that vitamin D might lower the risk of thefollowingEXCEPT _______.A) heart diseaseB) various cancersC) respiratory diseases D) autoimmune disorders4. The panel found most people ______.A) get vitamin D from supplementsB) worry they are vitamin D deficientC) get enough vitamin D from their dietD) need to take extra vitamin D supplement5.For some people, the studies about vitamin supplements are _______.A) confusing B) convincingC) appropriate D) specificKey to Task 71. B2. D3. C4. C5. AListen to the five sentences twice and interpret each into Chinese.1. The word osteoporosis means porous bones, or bones that are not solid enough. The disease harms bones by removing calcium骨质疏松这个词的意思是多孔的骨头，或骨骼不够坚实。

Line Blanks A N A M E R I C A N N A T I O N A L S T A N D A R DLine BlanksA N A M E R I C A N N A T I O N A L S T A N D A R DThree Park Avenue • New York, NY 10016Date of Issuance:January16,2006The next edition of this Standard is scheduled for publication in2010.There will be no addenda or written interpretations of the requirements of this Standard issued to this edition.ASME is the registered trademark of The American Society of Mechanical Engineers.This code or standard was developed under procedures accredited as meeting the criteria for American National Standards.The Standards Committee that approved the code or standard was balanced to ensure that individuals from competent and concerned interests have had an opportunity to participate.The proposed code or standard was made available for public review and comment that provides an opportunity for additional public input from industry,academia, regulatory agencies,and the public-at-large.ASME does not“approve,”“rate,”or“endorse”any item,construction,proprietary device,or activity.ASME does not take any position with respect to the validity of any patent rights asserted in connection with any items mentioned in this document and does not undertake to insure anyone utilizing a standard against liability for infringement of any applicable letters patent,nor assume any such ers of a code or standard are expressly advised that determination of the validity of any such patent rights,and the risk of infringement of such rights,is entirely their own responsibility.Participation by federal agency representative(s)or person(s)affiliated with industry is not to be interpreted as government or industry endorsement of this code or standard.ASME accepts responsibility for only those interpretations of this document issued in accordance with the established ASME procedures and policies,which precludes the issuance of interpretations by individuals.No part of this document may be reproduced in any form,in an electronic retrieval system or otherwise,without the prior written permission of the publisher.The American Society of Mechanical EngineersThree Park Avenue,New York,NY10016-5990Copyright©2006byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.CONTENTSForeword (iv)Committee Roster (v)1Scope (1)2Pressure-Temperature Ratings (1)3Design (2)4Dimensions (2)5Materials (3)6Marking (3)7Paddle Blank and Spacer Identification (3)8Testing (3)Figure1Line Blanks (2)Tables1Dimensions of Class150Raised Face Figure-8Blanks (4)2Dimensions of Class300Raised Face Figure-8Blanks (5)3Dimensions of Class600Raised Face Figure-8Blanks (6)4Dimensions of Class900Raised Face Figure-8Blanks (7)5Dimensions of Class1500Raised Face Figure-8Blanks (8)6Dimensions of Class2500Raised Face Figure-8Blanks (9)7Dimensions of Class150Female Ring-Joint Facing Figure-8Blanks (10)8Dimensions of Class300Female Ring-Joint Facing Figure-8Blanks (11)9Dimensions of Class600Female Ring-Joint Facing Figure-8Blanks (12)10Dimensions of Class900Female Ring-Joint Facing Figure-8Blanks (13)11Dimensions of Class1500Female Ring-Joint Facing Figure-8Blanks (14)12Dimensions of Class2500Female Ring-Joint Facing Figure-8Blanks (15)13Dimensions of Class150Male Oval Ring-Joint Facing Figure-8Blanks (16)14Dimensions of Class300Male Oval Ring-Joint Facing Figure-8Blanks (17)15Dimensions of Class600Male Oval Ring-Joint Facing Figure-8Blanks (18)16Dimensions of Class900Male Oval Ring-Joint Facing Figure-8Blanks (19)17Dimensions of Class1500Male Oval Ring-Joint Facing Figure-8Blanks (20)18Dimensions of Class2500Male Oval Ring-Joint Facing Figure-8Blanks (21)Nonmandatory AppendicesA Dimensional Data for Line Blanks in U.S.Customary Units (22)B References (41)C Quality System Program (42)iiiFOREWORDIn July1993,the ASME B16Committee gave to its Subcommittee C the assignment to convert the API590Steel Line Blanks Standard into an ASME standard.The American Petroleum Institute no longer publishes the API590Standard.These line blanks were designed in accordance with the rules of the ASME B31.3-2002edition. Materials and relevant footnotes have been added following the ASME format.Significant additions made to this2005edition include reference to the use of all materials listed in B16.5Table1-A plus Metric units.The added materials of construction include additions to classes of alloy steels,stainless steels,and nickel alloys.This edition has also been metricated over previous editions to include both U.S.Customary units(in parenthesis)and Metric units in the text,Metric units in dimensional tables in the body,and U.S.Customary units in dimensional tables in Nonmandatory Annex A.All requests for interpretations or suggestions for revisions should be sent to the Secretary, B16Committee,The American Society of Mechanical Engineers,Three Park Avenue,New York, NY10016-5990.The B16Committee operates under procedures accredited by the American National Standards Institute(ANSI).Following approval by the Standards Committee and ASME,this revision to the1997edition was approved as an American National Standard by ANSI on September19, 2005with the designation ASME B16.48-2005.ivASME B16COMMITTEE Standardization of Valves,Flanges,Fittings,and Gaskets(The following is the roster of the Committee at the time of approval of this Standard.)OFFICERSW.N.McLean,Chair R.A.Schmidt,Vice Chair C.Artibee,SecretaryCOMMITTEE PERSONNELR.W.Barnes,Anric Enterprises,Inc.W.B.Bedesem,ExxonMobil Research and Engineering Co.M.A.Clark,Nibco,Inc.C.E.Floren,Mueller Co.D.R.Frikken,Becht Engineering Co.G.G.Grills,U.S.Coast Guard A.Hamilton,ABS Americas M.L.Henderson,Forgital USA G.A.Jolly,Vogt Valves/Flowserve M.Katcher,Haynes International R.Koester,Honorary MemberSUBCOMMITTEE CD.R.Frikken,Chair,Becht Engineering Co.C.Artibee,Secretary,The American Society of Mechanical EngineersV.C.Bhasin,Sigmatech G.D.Conlee,Consultant W.C.Farrell,Jr.,Consultant M.L.Henderson,Coffer Corp.R.E.Johnson,Flowline DivisionvW.N.McLean,Newco ValvesT.A.McMahon,Fisher Controls International,Inc.M.L.Nayyar,Bechtel Power Corp.J.D.Page,U.S.Regulatory CommissionP .A.Reddington,The American Society of Mechanical Engineers R.A.Schmidt,Trinity-ladishH.R.Sonderegger,Anvil International,Inc.W.M.Stephan,Flexitallic LPT.F.Stroud,Ductile Iron Pipe Research Association R.E.White,Richard E.White &Associates PC D.A.Williams,Southern Company ServicesR.Koester,Honorary Member W.N.McLean,Newco ValvesM.L.Nayyar,Bechtel Power Corp.R.A.Schmidt,Trinity-ladish D.L.Shira,Taylor ForgeJ.C.Thompson,Milwaukee Valve L.A.Willis,Dow Chemical Co.viASME B16.48-2005 LINE BLANKS1SCOPE1.1GeneralThis Standard covers pressure-temperature ratings, materials,dimensions,tolerances,marking,and testing for operating line blanks in sizes NPS1⁄2through NPS24 for installation between ASME B16.5flanges in the150, 300,600,900,1500,and2500pressure classes.1.2Definitions1.2.1Figure-8Blank.A figure-8blank(also called a spectacle blank)is a pressure-retaining plate with one solid end and one open end connected with a web or tie bar(see Fig.1).1.2.2Paddle Blank.A paddle blank is similar to the solid end of a figure-8blank.It has a plain radial handle.It is generally used in conjunction with a paddle spacerin large sizes.1.2.3Paddle Spacer.A paddle spacer is similar to the open end of a figure-8blank.It has a plain radial handle.It is generally used in conjunction with a paddle blank.1.3ReferencesCodes,standards,and specifications,containing pro-visions to the extent referenced herein,constitute requirements of this Standard.These reference docu-ments are listed in Nonmandatory Appendix B.1.4Quality SystemsNonmandatory requirements relating to the product manufacturer’s Quality System Program are describedin Nonmandatory Appendix C.1.5Relevant UnitsThis Standard states values in both Metric and U.S.Customary units.These systems of units are to be regarded separately as standard.Within the text,the U.S.Customary units are shown in parenthesis or sepa-rate tables.Refer to Nonmandatory Appendix A.The values stated in each system are not exact equivalents; therefore,it is required that each system of units be used independently of the bining values from the two systems constitutes nonconformance with the Stan-dard.Nonmandatory Appendix A provides dimensionsin U.S.Customary units.1.6ConventionFor the purpose of determining conformance with this Standard,the convention for fixing significant digits1where limits and maximum and minimum values are specified,shall be rounded as defined in ASTM Practice E29.This requires that an observed or calcu-lated value shall be rounded off to the nearest unit in the last right-hand digit used for expressing the limit. Decimal values and tolerances do not imply a particular method of measurement.1.7SizeNPS,followed by a dimensionless number,is the des-ignation for nominal blank size.NPS is related to the reference nominal diameter,DN,as defined in ISO6708. The relationship is typically as follows:NPS DN1⁄2153⁄42012511⁄43211⁄24025021⁄2653804100NOTE:For NPS≥4,the related DN is DN p25(NPS).1.8Service ConditionsCriteria for selection of materials suitable for particu-lar fluid service are not wihtin the scope of this Standard.2PRESSURE-TEMPERATURE RATINGS2.1Pressure ClassesLine blanks covered by this Standard are for the fol-lowing pressure classes:150,300,600,900,1500,and 2500as listed in ASME B16.5.2.2Pressure-Temperature Ratings2.2.1Ratings.Ratings are the maximum allowable working gage pressure at the temperature shown in Tables2and F-2of ASME B16.5for the appropriate material and pressure class.For intermediate tempera-tures,linear interpolation between temperatures withina pressure class is permitted by ASME B16.5.2.2.2System Pressure Testing.Line blanks may be subjected to system tests at a pressure not to exceed 1.5times the38°C(100°F)rating rounded off to the next higher1bar(25psi)increment.Testing at any higher pressure is the responsibility of the user,taking intoASME B16.48-2005LINE BLANKSFigure-8 BlankPaddle BlankPaddle SpacerFig.1Line Blanksaccount the requirements of the applicable code or regulation.2.2.3Mixed Material Joints.Should either the two flanges or the line blank in a flanged line blank assembly not have the same pressure-temperature rating,the rat-ing of the assembled joint at any temperature shall be the lower of the flange or line blank rating at that temper-ature.3DESIGN3.1HandleThe handle or web(tie bar)may be integral or attached to the line blank or spacer.The web and its attachment shall be capable of supporting the weight of the blank or spacer in all orientations without permanent defor-mation to the web.3.2Edge PreparationFinished surfaces shall be free of projections that would interfere with gasket seating.3.3Facing3.3.1Raised Face Joint Blanks.The gasket seating surface finish and dimensions for raised face line blanks shall be in accordance with ASME B16.5.A raised face may be specified at the option of the purchaser.The height of the raised faces shall be in addition to the2thicknesses,t,listed in Tables1through6(Tables A-1 through A-6in Nonmandatory Appendix A).3.3.2Female Ring-Joint Blanks.Female ring-joint grooves shall be shaped with the groove side wall sur-face finish not exceeding1.6␮m(63␮in.)Ra roughness. The finish of the gasket contact faces shall be judged by visual comparison with Ra standards(see ASME B46.1) and not by instruments having stylus tracers and elec-tronic amplification.3.3.3Male Ring-Joint Blanks.The gasket shape(ring) for male ring-joint blanks shall not exceed1.6␮m (63␮in.)Ra roughness.The finish of the gasket contact faces shall be judged by visual comparison with Ra stan-dards(see ASME B46.1)and not by instruments having stylus tracers and electronic amplification.4DIMENSIONS4.1GeneralDimensions shall be in accordance with Tables1 through18(Tables A-1through A-18of Nonmandatory Appendix A).4.2Tolerances4.2.1Facing Tolerances.Tolerances for facings shall be in accordance with ASME B16.5.4.2.2Thickness Tolerances.Thickness tolerances are NPS18and smaller−zero+3.0mm(0.12in.)NPS20and larger−zero+4.8mm(0.19in.)4.3Openings(a)For NPS1⁄2,NPS3⁄4,and NPS1blanks in all raised face classes,the inside diameter is equal to standard weight welding neck flange bore.(b)For NPS11⁄4and larger blanks in Classes150and 300raised face,the inside diameter is equal to the pipe outside diameter.(c)For NPS11⁄4and larger blanks in Classes600and 900raised face,the inside diameter is equal to Schedule10S welding neck flange bore.(d)For Class1500raised face blanks,the inside diam-eter is equal to Schedule40welding neck flange bore.(e)For Class2500raised face blanks,the inside diame-ter is equal to Schedule40through NPS6,Schedule60 for NPS8and NPS10,and Schedule80for NPS12. (f)For all ring-joint blanks,the inside diameter is equal to the pipe outside diameter.(g)Dimensions are based upon concentric installation of spiral wound gaskets with inner rings as required by ASME B16.20and conform to the maximum permitted bore of ASME B16.5welding neck flanges described in Table16of ASME B16.20.LINE BLANKS ASME B16.48-20054.4Facing FinishFacing finish shall be in accordance with ASME B16.5, para.6.4.5.5MATERIALSMaterials for line blanks shall be in accordance with ASME B16.5,Table1-A,and shall include material restrictions cited in notes to Tables2or F-2of ASME B16.5.Recommended bolting materials for flange-blank assemblies are listed in ASME B16.5, Table1-B.Criteria for the selection of materials are not within the scope of this Standard.6MARKING6.1General(a)Line blanks shall be marked as follows:(1)Manufacturer’s name or trademark(2)Material,specification,and grade or class(3)Pressure class(4)B16(5)Size(NPS)(6)Ring number(if applicable)(b)Where space does not permit all of the above markings,they may be omitted in the reverse order given in 6.1(a).3(c)The B16designation may be applied only when the line blank has been manufactured in full confor-mance with this Standard.6.2Marking MethodThe marking shall be applied by steel stamping on the web(tie bar)or handle.Where space is limited, marking may be stamped on the outside edge of the blind portion of blanks.7PADDLE BLANK AND SPACER IDENTIFICATION 7.1Paddle HandlesIn order to differentiate between an installed paddle spacer and a paddle blank,it is required that there be an externally visible distinction between the two as required by paras.7.2and7.3.7.2Paddle Blank HandlesHandles for paddle blanks shall be solid with no openings.7.3Paddle Spacer HandlesHandles for paddle spacers shall have a single through indicator hole located near the end of the handle.The hole diameter shall not be less than12mm(1⁄2in.).8TESTINGLine blanks are not required to be pressure tested.Table1Dimensions of Class150Raised Face Figure-8Blanks Inside Outside CenterlineDiameter,B,Diameter,O,Dimension,A,Thickness,t,Web Width,W, NPS mm mm mm mm mm1⁄2164560 3.0383⁄4215470 3.038 1276480 3.03811⁄4427390 6.43811⁄24883100 6.438 261102120 6.45121⁄273107140 6.451 389133150 6.46431⁄21021591759.764 41141721909.764 51411942159.776 616821924012.776 821927630012.776 1027333736015.7102 1232440643019.1102 1435644847519.1108 1640651146022.4108 1845754658025.4114 2050860363528.4121 2461071475031.8140GENERAL NOTE:Dimensions are in millimeters.For inch dimensions,refer to corresponding Table A-1in Nonmandatory Appendix A.NOTES:(1)Hole size(where required due to bolt spacing)shall be the same as the flange bolt hole and locatedsuch that it will not interfere with bolting between two flanges.(2)The thickness of the web(or tie bar)dimension,W t,shall be as determined by para.3.1.(3)Refer to para.3.3.1.Table2Dimensions of Class300Raised Face Figure-8Blanks Inside Outside CenterlineDiameter,B,Diameter,O,Dimension,A,Thickness,t,Web Width,W, NPS mm mm mm mm mm1⁄2165165 6.4383⁄4216480 6.438 1277090 6.43811⁄44279100 6.43811⁄24892115 6.438 2611081259.75121⁄2731271509.751 3891461709.76431⁄210216218512.764 411417820012.764 514121323515.776 616824827015.776 821930533022.476 1027335938525.4102 1232441945028.4102 1435648351531.8108 1640653657038.1108 1845759463041.1114 2050865168544.5121 2461077281050.8140GENERAL NOTE:Dimensions are in millimeters.For inch dimensions,refer to corresponding Table A-2in Nonmandatory Appendix A.NOTES:(1)Hole size(where required due to bolt spacing)shall be the same as the flange bolt hole and locatedsuch that it will not interfere with bolting between two flanges.(2)The thickness of the web(or tie bar)dimension,W t,shall be as determined by para.3.1.(3)Refer to para.3.3.1.Table3Dimensions of Class600Raised Face Figure-8Blanks Inside Outside CenterlineDiameter,B,Diameter,O,Dimension,A,Thickness,t,Web Width,W, NPS mm mm mm mm mm1⁄2165165 6.4383⁄4216480 6.438 1277090 6.45711⁄437791009.75711⁄243921159.767 2551081259.75721⁄26712715012.767 38314617012.76731⁄29615918515.776 410819121515.776 513523826519.186 616226429022.486 821231835028.495 1026539743035.1105 1231545449041.1105 1434648952544.5114 1639756260550.8124 1844861065553.8133 2049767972563.5133 2459778784073.2152GENERAL NOTE:Dimensions are in millimeters.For inch dimensions,refer to corresponding Table A-3in Nonmandatory Appendix A.NOTES:(1)Hole size(where required due to bolt spacing)shall be the same as the flange bolt hole and locatedsuch that it will not interfere with bolting between two flanges.(2)The thickness of the web(or tie bar)dimension,W t,shall be as determined by para.3.1.(3)Refer to para.3.3.1.Table4Dimensions of Class900Raised Face Figure-8Blanks Inside Outside CenterlineDiameter,B,Diameter,O,Dimension,A,Thickness,t,Web Width,W, NPS mm mm mm mm mm1⁄2166080 6.4383⁄4216790 6.441 12776100 6.45711⁄437861109.75711⁄243951259.767 25514016512.75721⁄26716219012.767 38316519015.767 410820323519.176 513524428022.486 616228632025.486 821235639535.195 1026543247041.1105 1231549553547.8105 1434651856053.8114 1639757261560.5124 1844863568566.5133 2049769675073.2133 2459783590088.9152GENERAL NOTE:Dimensions are in millimeters.For inch dimensions,refer to corresponding Table A-4in Nonmandatory Appendix A.NOTES:(1)Hole size(where required due to bolt spacing)shall be the same as the flange bolt hole and locatedsuch that it will not interfere with bolting between two flanges.(2)The thickness of the web(or tie bar)dimension,W t,shall be as determined by para.3.1.(3)Refer to para.3.3.1.Table5Dimensions of Class1500Raised Face Figure-8Blanks Inside Outside CenterlineDiameter,B,Diameter,O,Dimension,A,Thickness,t,Web Width,W, NPS mm mm mm mm mm1⁄2166180 6.4383⁄42167909.741 127761009.76411⁄435861109.76411⁄2419512512.770 25314016512.77021⁄26316219015.776 37817220519.176 410220624022.489 512825129028.489 615427932035.189 820334939541.1102 1025543248050.8114 1230351857060.5114 1433357563566.5127 1638163870576.2133 1842970277585.9146 2047875283095.3152 24575899990111.3178GENERAL NOTE:Dimensions are in millimeters.For inch dimensions,refer to corresponding Table A-5in Nonmandatory Appendix A.NOTES:(1)Hole size(where required due to bolt spacing)shall be the same as the flange bolt hole and locatedsuch that it will not interfere with bolting between two flanges.(2)The thickness of the web(or tie bar)dimension,W t,shall be as determined by para.3.1.(3)Refer to para.3.3.1.Table6Dimensions of Class2500Raised Face Figure-8Blanks Inside Outside CenterlineDiameter,B,Diameter,O,Dimension,A,Thickness,t,Web Width,W, NPS mm mm mm mm mm1⁄21667909.7383⁄42173959.741 127831109.76411⁄43510213012.76411⁄24111414515.770 25314317015.77021⁄26316519519.176 37819423022.476 410223227528.489 512827632535.189 615431437041.189 819838444053.8102 1024847354066.5114 1228954662079.2114GENERAL NOTE:Dimensions are in millimeters.For inch dimensions,refer to corresponding Table A-6in Nonmandatory Appendix A.NOTES:(1)Hole size(where required due to bolt spacing)shall be the same as the flange bolt hole and locatedsuch that it will not interfere with bolting between two flanges.(2)The thickness of the web(or tie bar)dimension,W t,shall be as determined by para.3.1.(3)Refer to para.3.3.1.Table7Dimensions of Class1500Female Ring-Joint Facing Figure-8Blanks Inside Outside CenterlineDiameter,B,Diameter,O,Dimension,A,Thickness,t,Web Width,W, NPS mm mm mm mm mm 134648019.15111⁄442739019.15111⁄2488310019.157 26110212019.15721⁄27312114022.457 38913315022.45731⁄210215417522.464 411417219022.464 514119421525.470 616821924025.483 821927330028.495 1027333036031.8102 1232440643035.1121 1435642647535.1127 1640648354038.1127 1845754658041.1127 2050859763541.1127 2461071175047.8152 GENERAL NOTE:Dimensions are in millimeters.For inch dimensions,refer to corresponding Table A-7in Nonmandatory Appendix A.NOTES:(1)Hole size(where required due to bolt spacing)shall be the same as the flange bolt hole and locatedsuch that it will not interfere with bolting between two flanges.(2)Female ring-joint groove dimensions shall be in accordance with ASME B16.5.(3)The thickness of the web(or tie bar)dimension,W t,shall be as determined by para.3.1.Table8Dimensions of Class300Female Ring-Joint Facing Figure-8Blanks Inside Outside CenterlineDiameter,B,Diameter,O,Dimension,A,Thickness,t,Web Width,W, NPS mm mm mm mm mm1⁄221516515.7383⁄427648019.145 134709019.15111⁄4427910022.45111⁄2489011522.457 26110812525.45721⁄27312715028.457 38914617028.45731⁄210215918528.464 411417520031.864 514121023535.170 616824127035.183 821930233041.195 1027335638544.5102 1232441345050.8121 1435645751553.8127 1640650857057.2127 1845757563060.5127 2050863568569.9127 2461074981079.2152GENERAL NOTE:Dimensions are in millimeters.For inch dimensions,refer to corresponding Table A-8in Nonmandatory Appendix A.NOTES:(1)Hole size(where required due to bolt spacing)shall be the same as the flange bolt hole and locatedsuch that it will not interfere with bolting between two flanges.(2)Female ring-joint groove dimensions shall be in accordance with ASME B16.5.(3)The thickness of the web(or tie bar)dimension,W t,shall be as determined by para.3.1.Table9Dimensions of Class600Female Ring-Joint Facing Figure-8Blanks Inside Outside CenterlineDiameter,B,Diameter,O,Dimension,A,Thickness,t,Web Width,W, NPS mm mm mm mm mm1⁄221516519.1383⁄427648022.445 134709022.45111⁄4427910022.45111⁄2489011522.457 26110812528.45721⁄27312715031.857 38914617031.85731⁄210215918535.164 411417521535.164 514121026538.170 616824129044.583 821930235050.895 1027335643057.2102 1232441349063.5121 1435645752566.5127 1640650860573.2127 1845757565579.2127 2050863572588.9127 24610749840104.6152GENERAL NOTE:Dimensions are in millimeters.For inch dimensions,refer to corresponding Table A-9in Nonmandatory Appendix A.NOTES:(1)Hole size(where required due to bolt spacing)shall be the same as the flange bolt hole and locatedsuch that it will not interfere with bolting between two flanges.(2)Female ring-joint groove dimensions shall be in accordance with ASME B16.5.(3)The thickness of the web(or tie bar)dimension,W t,shall be as determined by para.3.1.Table10Dimensions of Class900Female Ring-Joint Facing Figure-8Blanks Inside Outside CenterlineDiameter,B,Diameter,O,Dimension,A,Thickness,t,Web Width,W, NPS mm mm mm mm mm1⁄221618022.4383⁄427679022.445 1347110022.45111⁄4428111025.45111⁄2489212525.464 26112416531.85121⁄27313719035.167 38915519035.167 411418123541.173 514121628044.573 616824131547.873 821930839557.280 1027336247063.5121 1232441953573.2121 1435646756082.6121 1640652461591.9127 18457594685101.6133 20508648750111.3127 24610772900133.4140 GENERAL NOTE:Dimensions are in millimeters.For inch dimensions,refer to corresponding Table A-10 in Nonmandatory Appendix A.NOTES:(1)Hole size(where required due to bolt spacing)shall be the same as the flange bolt hole and locatedsuch that it will not interfere with bolting between two flanges.(2)Female ring-joint groove dimensions shall be in accordance with ASME B16.5.(3)The thickness of the web(or tie bar)dimension,W t,shall be as determined by para.3.1.ASME B16.48-2005LINEBLANKSTable11Dimensions of Class1500Female Ring-Joint Facing Figure-8BlanksInside Outside CenterlineDiameter,B,Diameter,O,Dimension,A,Thickness,t,Web Width,W,NPS mm mm mm mm mm1⁄221618022.4383⁄427679025.445 1347110025.45411⁄4428111025.45411⁄2489212528.457 26112416535.15421⁄27313719038.157 38916820544.573 411419424047.876 514122929053.876 616824831560.579 821931839573.286 1027337148082.5133 12324438570101.6133 14356489635111.3140 16406546705124.0146 18457613775133.0152 20508673830142.7165 24610794990168.1178 GENERAL NOTE:Dimensions are in millimeters.For inch dimensions,refer to corresponding Table A-11 in Nonmandatory Appendix A.NOTES:(1)Hole size(where required due to bolt spacing)shall be the same as the flange bolt hole and locatedsuch that it will not interfere with bolting between two flanges.(2)Female ring-joint groove dimensions shall be in accordance with ASME B16.5.(3)The thickness of the web(or tie bar)dimension,W t,shall be as determined by para.3.1.LINE BLANKS ASMEB16.48-2005Table12Dimensions of Class2500Female Ring-Joint Facing Figure-8BlanksInside Outside CenterlineDiameter,B,Diameter,O,Dimension,A,Thickness,t,Web Width,W,NPS mm mm mm mm mm1⁄221659025.4383⁄427739528.445 1348311028.45411⁄44210213035.15411⁄24811414538.161 26113317041.15721⁄27314919547.861 38916823050.876 411420327063.583 514124132573.289 616827937082.695 821934044098.695 10273425540117.391 12324495620133.4152GENERAL NOTE:Dimensions are in millimeters.For inch dimensions,refer to corresponding Table A-12 in Nonmandatory Appendix A.NOTES:(1)Hole size(where required due to bolt spacing)shall be the same as the flange bolt hole and locatedsuch that it will not interfere with bolting between two flanges.(2)Female ring-joint groove dimensions shall be in accordance with ASME B16.5.(3)The thickness of the web(or tie bar)dimension,W t,shall be as determined by para.3.1.ASME B16.48-2005LINE BLANKSTable13Dimensions of Class150Male Oval Ring-Joint Facing Figure-8BlanksInside CenterlineDiameter,B,Dimension,A,Thickness,t,Web Width,W,NPS mm mm mm mm13480 6.45111⁄44290 6.45111⁄248100 6.457261120 6.45721⁄2731409.7573891509.75731⁄21021759.76441141909.764514121512.776616824012.783821930015.7951027336219.11021232443222.41211435647622.41271640654025.41271845757828.41272050863528.41272461074935.1152GENERAL NOTE:Dimensions are in millimeters.For inch dimensions,refer to corresponding Table A-13in Nonmandatory Appendix A.NOTES:(1)Hole size(where required due to bolt spacing)shall be the same as the flange bolt hole and locatedsuch that it will not interfere with bolting between two flanges.(2)Oval ring-joint dimensions shall be in accordance with ASME B16.20,except T h p T+t,where T isthe ring height specified in ASME B16.20.(3)The thickness of the web(or tie bar)dimension,W t,shall be as determined by para.3.1.。