ASME B16.5 is the most common use standard specification for manufacturing cast and forged steel pipe flange and flanged fittings.

ASME B16.5是制造铸锻钢管法兰和法兰配件最常用的标准规范。

The Brief History of ASME B16.5

ASME B16.5简史

ASME B16.5 is the standard specification for pipe flanges and flanged fittings sized from NPS 1/2 (DN 15) to NPS 24 (DN 600). It is the most widely used flange standard in piping industry. This standard is developed by the sectional Committee B16 of Americal Standards Association (ASA). It is derived from the 1932 revision of ASA B16E. During its development history, the standard had been published as ASA B16.5, ANSI B16.5, ASME/ ANSI B16.5. Then, on October 3, 1996, it was approved with the new formal designation ASME B16.5. So far, we have several editions of ASME B16.9: 2003, 2009, and 2013.

ASME B16.5是尺寸从NPS 1/2（DN 15）到NPS 24（DN 600）的管道法兰和法兰配件的标准规范。它是管道行业中使用最广泛的法兰标准。本标准由美国标准协会（ASA）B16分会制定。它源自1932年修订的ASA B16E。在其发展历史上，该标准曾被发布为ASA B16.5、ANSI B16.5、ASME/ANSI B16.5。然后，在1996年10月3日，它被批准为新的正式名称ASME B16.5。到目前为止，草莓视频APP下载污有几个版本的ASME B16.9:2003、2009和2013。

ASME B16.5 standard covers pressure-temperature ratings, materials, dimensions, tolerances, marking, testing, and methods of designating openings for pipe flange and flanged fittings. ASME B16.5 standard covers Steel Pipe Flanges and Flanged Fittings from NPS 1/2 through NPS 24 Metric/Inch in pressure class 150 to class 2500. 

ASME B16.5标准涵盖了压力温度额定值、材料、尺寸、公差、标记、测试以及为管道法兰和法兰配件指定开口的方法。ASME B16.5标准涵盖了压力等级为150至2500的NPS 1/2至NPS 24公制/英寸的钢管法兰和法兰配件。

ASME B16.5 limited to:

ASME B16.5仅限于：

• Flanges and flanged fittings made from cast or forged materials由铸造或锻造材料制成的法兰和法兰配件
• Blind flanges and certain reducing flanges made from cast, forged or plate materials.盲板和某些由铸造、锻造或板材制成的异径法兰。
• Flange bolting, gaskets and joints.法兰螺栓、垫片和接头。

Unit单元

Flanges with rating class of 150#, 300#, 400#, 600#, 900# and 1500# in sizes NPS 1/2 to 24. For 2500# in sizes from NPS 1/2 to NPS 12, with requirements in both metric and U.S. Customary units with diameter of bolts and flange bolt holes expressed in inch units.

额定等级为150#、300#、400#、600#、900#和1500#的法兰，尺寸为NPS 1/2至24。对于尺寸从NPS 1/2到NPS 12的2500#，要求采用公制和美国惯用单位，螺栓和法兰螺栓孔的直径以英寸单位表示。

Flanged fittings with 150#, 300# in sizes of NPS 1/2 to NPS 24, expressed in inch Units.

尺寸为NPS 1/2至NPS 24的150#、300#法兰配件，单位为英寸。

Flanged fittings with 400#, 600#, 900#, and 1500# from NPS 1/2 to NPS24, and 2500# from NPS 1/2 to NPS 12, which only US. Customary units are provided. More details visit Nonmandatory Appendix E in ASME B16.5.

NPS 1/2至NPS24的400#、600#、900#和1500#以及NPS 1/2至NPS 12的2500#法兰配件，仅提供美国惯用单位。更多详细信息请访问ASME B16.5中的非强制性附录E。

ASME B16.5 Ratings Designation

ASME B16.5额定值名称

Class, followed by a dimensionless number, is the designation for pressure-temperaure ratings as follows:

压力-温度额定值的名称如下：

Class   150   300   400   600   900   1500   2500

Size

In NPS, is designation for nominal flange or flange fittings size. NPS related to nominal diameter, DN in international standards, relations as below:

在NPS中，表示标称法兰或法兰配件尺寸。NPS与公称直径、DN在国际标准中的关系如下：

Note: For NPS ≥ 4, the related DN = 25 multiplied by the NPS number. For example NPS 10 is DN250.

注：对于NPS≥4的情况，相关DN=25乘以NPS编号。例如，NPS 10为DN250。

Pressure-Temperature Rating压力温度额定值

The pressure-temperature rating is the maximum allowable working pressure (bar unit) of the material and grade used at the rated temperature (Celsius).

Flanged Joints

压力温度额定值是在额定温度（摄氏度）下使用的材料和等级的最大允许工作压力（巴单位）。

法兰接头

A flanged joint is composed of separate and independent, although interrelated components: the flanges, gasket, and bolting, which are assembled by another influence, the assembler. Proper controls must be exercised in the selection and application for all these elements to attain a joint that has acceptable leak tightness. Special techniques, such as controlled bolt tightening, are described in ASME PCC-1

法兰接头由单独且独立但相互关联的部件组成：法兰、垫片和螺栓，这些部件由另一个影响因素组装而成，即组装人员。在选择和应用所有这些元件时必须进行适当的控制，以获得具有可接受密封性的接头。ASME PCC-1中描述了特殊技术，如受控螺栓拧紧

Mixed Flanged Joints混合法兰接头

If the flanges of a flange joint have different pressure-temperature ratings, the flange joint shall be rated for the lower of the two ratings at that temperature at any temperature.

如果法兰接头的法兰具有不同的压力-温度额定值，则法兰接头在任何温度下在该温度下的额定值应为两个额定值中的较低值。

Rated temperature额定温度

The rated temperature corresponding to the rated pressure is refers to the temperature of the pressure vessel of the flange and flange fittings. This temperature is generally the same as the temperature of the stored liquid.

额定压力对应的额定温度是指法兰和法兰配件的压力容器的温度。该温度通常与储存液体的温度相同。

Use of a pressure rating corresponding to a temperature other than that of the contained fluid is the responsibility of the user, subject to the requirements of applicable codes and regulations. For any temperature below−29°C (−20°F),the rating shall be no greater than the rating shown for −29°C(−20°F).

根据适用规范和法规的要求，用户有责任使用与所含流体温度以外的温度相对应的压力等级。对于低于-29°C（-20°F）的任何温度，额定值不得大于-29°C（-20°F）所示的额定值。

Temperature Consideration

温度考虑因素

Whether flange joints are used at high or low temperatures, leakage due to external forces and moments generated by the connected piping or equipment should be considered. To prevent leakage, pipe flanges and flanged fittings should avoid the application of severe external loads and sharp thermal gradients.

无论法兰接头是在高温还是低温下使用，都应考虑连接管道或设备产生的外力和力矩造成的泄漏。为防止泄漏，管道法兰和法兰配件应避免施加严重的外部载荷和急剧的热梯度。

High Temperature高温

Application at temperatures in the creep range will result in decreasing bolt loads as relaxation of flanges, bolts, and gaskets takes place. Flanged joints subjected to thermal gradients may likewise be subject to decreasing bolt loads. Decreased bolt loads diminish the capacity of the flanged joint to sustain loads effectively without leakage. At temperatures above 200°C (400°F) for Class 150 and above 400°C (750°F) for other class designations, flanged joints may develop leakage problems unless care is taken to avoid imposing severe external loads, severe thermal gradients, or both.

在蠕变范围内的温度下应用会导致螺栓载荷降低，因为法兰、螺栓和垫片会松弛。承受热梯度的法兰接头可能同样会受到螺栓载荷的减小。螺栓载荷的减少会降低法兰接头有效承受载荷而不泄漏的能力。在150级温度高于200°C（400°F）和其他等级温度高于400°C（750°F）的情况下，法兰接头可能会出现泄漏问题，除非注意避免施加严重的外部载荷、严重的热梯度或两者兼而有之。

Low Temperature低温

Some materials, especially some carbon steel materials, exhibit a significant decrease in ductility when used at low temperatures, and thus cannot withstand impact load, sudden stress changes, and high stress concentrations. Some regulations require an impact test even when the temperature is above -29 °C (−20°F).

一些材料，特别是一些碳钢材料，在低温下使用时延展性显著降低，因此无法承受冲击载荷、突然的应力变化和高应力集中。即使温度高于-29°C（-20°F），一些法规也要求进行冲击试验。

System Hydrostatic Testing系统水压试验

Flanged joints and flanged fittings may be subjected to system hydrostatic tests at a pressure of 1.5 times the 38°C (100°F) rating rounded off to the next higher 1 bar (25 psi)
increment. Testing at any higher pressure is the responsibility of the user,taking into account the requirements of the applicable code or regulation.

法兰接头和法兰配件可以在38°C（100°F）额定值的1.5倍压力下进行系统静水压试验，四舍五入到下一个更高的1巴（25磅/平方英寸）

增量。考虑到适用规范或法规的要求，用户有责任在任何更高的压力下进行测试。

Identification Markings识别标记

A ASME B16.5 flange shall furnished with below marking requirements. Flange and flange fittings shall be marked in accordance with MSS SP-25 except for modifications to this specification.

ASME B16.5法兰应具有以下标记要求。除本规范的修改外，法兰和法兰配件应按照MSS SP-25进行标记。

• Name: Manufacturer name or trademark制造商名称或商标
• Material: Cast or Forged, material standard ASTM xxx.材料：铸造或锻造，材料标准ASTM xxx。
• Pressure Ratings: Class 150 to 2500压力等级：150至2500级
• Conformance: ASME B16.5 or other B16 standard.符合性：ASME B16.5或其他B16标准。
• Temperature温度
• Size尺寸
• Ring Joint Flanges: Shall be marked with letter R and ring groove number.环形接头法兰：应标有字母R和环形槽编号。
• Multiple Material Marking: In case multiple material used.多种材料标记：如果使用多种材料。

Materials材料

Material required for flanges and flanged fittings commonly are:法兰和法兰配件所需的材料通常是：

• ASTM A105 for forged carbon steel flange·ASTM A105锻造碳钢法兰
• ASTM A350 for forged carbon steel, low alloy steel flange ·ASTM A350适用于锻造碳钢、低合金钢法兰
• ASTM A182 for alloy steel flange and stainless steel flange·ASTM A182适用于合金钢法兰和不锈钢法兰
• ASTM A216 for casting carbon steel flanges·ASTM A216铸造碳钢法兰
• ASTM A352, ASTM A217
• ASTM A515 Gr 70, 65 for plates flange·ASTM A515 Gr 70，65用于板法兰
• ASTM A516 Gr 70, 65 for carbon and low alloy steel plates flange·ASTM A516 Gr 70，65用于碳和低合金钢板法兰
• ASTM A203, A204
• ASTM A387 Gr 11, 22, 91 CL 2 for alloy steel plates flange   ASTM A387 Gr 11, 22, 91 CL 2 for alloy steel plates flange
• ASTM A240 Grade 304/L, 316/L for stainless steel plate flange  ·ASTM A240 304/L、316/L级不锈钢板法兰

Notes:笔记：

1. Plate and flat bar materials shall be used only for blind flanges and reducing flanges without hubs.

（1） 板和扁钢材料只能用于无轮毂的盲板法兰和异径法兰。

(2) Flanges and flanged fittings shall be manufactured as one piece in accordance with the applicable material specification. Assembly of multiple pieces into the finished product by welding or other means is not permitted by this Standard

（2） 法兰和法兰配件应按照适用的材料规范作为一个整体制造。本标准不允许通过焊接或其他方式将多个零件组装成成品

Mechanical properties机械性能

The mechanical properties shall be determined from the specimen and the specimen shall represent the final heat treated condition of the material as required by the material standard.

机械性能应由试样确定，试样应代表材料标准要求的材料最终热处理状态。

Bolts螺栓

Include high strength bolts, medium strength bolts, low strength bolts and bolts for grey cast iron flanges.

包括高强度螺栓、中强度螺栓、低强度螺栓和灰口铸铁法兰螺栓。

Gasket垫片

The material of the ring gasket shall comply with ASME B 16.20. The user is responsible for selecting gasket materials that are suitable for operating conditions, can withstand bolt loads, and do not cause cracking.

环形垫片的材料应符合ASME B 16.20。用户有责任选择适合操作条件、能够承受螺栓载荷且不会导致开裂的垫片材料。

ASME B16.5 Flange DimensionsASME B16.5法兰尺寸

ASME B16.5 flange dimensions including different pressure ratings for weld neck flange, slip on flange, blind flange, reducing flange, socket weld flange, threaded flange, view below for more details.

ASME B16.5法兰尺寸，包括焊颈法兰、滑套法兰、盲板法兰、异径法兰、承插焊法兰、螺纹法兰的不同压力等级，详见下图。

Class 150, 300, 600 Flange Dimensions150、300、600级法兰尺寸

• Ring Joint Facing Dimensions  环形接头端面尺寸
• Class 150 Flange Dimensions  150级法兰尺寸
• Class 300 Flange Dimensions  300级法兰尺寸
• Class 600, 900, 1500, 2500 Flange Dimensions  600、900、1500、2500级法兰尺寸

Tolerance公差

In order to determine compliance with this standard, where a fixed effective number is required where the limits, maximum and minimum values are specified, rounding shall be  in accordance with the method defined in ASTM Practice E29.

为了确定是否符合本标准，如果需要一个固定的有效数字，其中规定了限值、最大值和最小值，则应按照ASTM规程E29中定义的方法进行四舍五入。

Required tolerances for different flanges and flanged fittings elements are as follows:

不同法兰和法兰配件元件的所需公差如下：

Center to Contract Surfaces and Center to End Tolerances中心到合同表面和中心到端公差

(a). Center-to-Contract Surfaces other than Ring Joint除环形接头外的中心至接触面

(b). Center-to-End (Ring Joint)中心到端（环形接头）

(c). Center surface-to-Contact surface other than ring joint中心表面至接触面（环形接头除外）

(d). End-to-End端到端

Tolerances for Flange Facings法兰面公差

For both flange and flanged fittings facings tolerances are as follows:法兰和法兰配件的表面公差如下：

(a) Inside and outside diameter of large and small tongue and groove and female, ±0.5 mm (±0.02 in.). 大小榫槽和阴螺纹的内径和外径，±0.5 mm（±0.02 in.）。
(b) Outside diameter,2.0 mm (0.06 in.) raised face, ±1.0 mm (±0.03 in.). 外径，2.0毫米（0.06英寸）凸面，±1.0毫米（±0.03英寸）。
(c) Outside diameter, 7.0 mm (0.25 in.) raised face, ±0.5 mm (±0.02 in.).  外径，7.0毫米（0.25英寸）凸面，±0.5毫米（±0.02英寸）。
(d) Ring joint groove tolerances are shown in Table 5 (Table II-5 of Mandatory Appendix II in ASME B16.5) 环接头槽公差如表5所示（ASME B16.5强制性附录II表II-5）
(e)Perpendicularity of the face with the bore as below table表面与钻孔的垂直度如下表所示

Flange thickness tolerances法兰厚度公差

The plus tolerance is applicable to bolting bearing surfaces whether as-forged, as-cast, spot-faced, or back-faced.

正公差适用于螺栓连接轴承表面，无论是锻造、铸造、点焊还是背面。

Welding end flange ends and hubs焊接端部法兰端和轮毂

Outside Diameter外径

For welding ends of welding neck flanges nominal outside diameter as follows:焊接颈法兰的焊接端标称外径如下：

Inside Diameter内径

Tolerances for nominal inside diameter of welding ends of weld neck flange and socket weld flange with smaller bore.

焊接颈法兰和小口径承插焊法兰焊接端的标称内径公差。

1. For figures 7 (Bevel for wall thickness  from 5 mm to 22 mm), figure 8 (greater than 22 mm) and figure 4 (Straight Hub Welding Flange) in ASME B16.5.

（a） 对于ASME B16.5中的图7（壁厚为5mm至22mm的斜面）、图8（大于22mm）和图4（直轮毂焊接法兰）。

For figure 9 (Inside Contour for Use With Rectangular Backing Ring)图9（与矩形垫环一起使用的内部轮廓）

Backing ring contact surface垫环接触面

Length through hub on welding neck flanges焊接颈法兰上穿过轮毂的长度

Flange Bore Diameter法兰孔直径

Lapped and Slip-On Flange Bores研磨和滑动法兰孔

Counter Bores, Threaded Flanges钻孔、螺纹法兰

Counter Bores, Socket Welding Flanges钻孔、承插焊接法兰

Pressure Test压力测试

No pressure test is required on the flange.法兰无需进行压力测试。

Flanged fitting should be tested for shell pressure. 法兰接头应进行壳体压力测试。 

Shell Pressure Test for Flanged Fittings法兰管件的壳体压力试验

The shell pressure test for flanged fittings shall be at a pressure no less than 1.5 times the 38°C (100°F) pressure rating rounded off to the next higher 1 bar (25 psi) increment.

法兰配件的壳体压力试验应在不小于38°C（100°F）压力额定值1.5倍的压力下进行，四舍五入到下一个更高的1bar（25磅/平方英寸）增量。

Test Conditions试验条件

The shell pressure test for flanged fittings shall be at a pressure no less than 1.5 times the 38°C (100°F) pressure rating rounded off to the next higher 1 bar (25 psi) increment

法兰配件的壳体压力试验应在不小于38°C（100°F）压力额定值1.5倍的压力下进行，四舍五入到下一个更高的1bar （25磅/平方英寸）增量

Test Duration测试持续时间