ASME B16.20-2012 管法兰用环垫式

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 D

ASME B16.20-2012

(Revision of ASME B16.20-2007)

Metallic Gaskets for Pipe Flanges

Ring-Joint, Spiral-Wound, and Jacketed Copyright ASME International Provided by IHS under license with ASME

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Metallic Gaskets

for Pipe Flanges

Ring-Joint,Spiral-Wound,

and Jacketed

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 D

Two Park Avenue ? New York, NY ? 10016 USA

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Date of Issuance:June25,2013

The next edition of this Standard is scheduled for publication in2017.

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CONTENTS

Foreword (v)

Committee Roster (vi)

Correspondence With the B16Committee (vii)

Important Information Concerning Use of Asbestos or Alternative Materials (viii)

Summary of Changes (xi)

1Scope (1)

2Ring-Joint Gaskets (1)

3Spiral-Wound Gaskets (2)

4Jacketed Gaskets (3)

5Grooved Metal Gaskets With Covering Layers (3)

Figures

1Spiral-Wound Gaskets(Metric) (5)

2Jacketed Gaskets(Metric) (5)

3Grooved Metal Gasket With Covering Layers (6)

4Illustration of Example Markings for Grooved Metal

Gasket With Covering Layers (7)

Tables

1Maximum Hardness for Ring Gaskets (1)

2Ring Gasket Markings (2)

3Type R Ring Gasket Dimensions and Tolerances (8)

4Pipe Sizes for Type R Ring Gaskets Suitable for Referenced Standards (11)

5Type RX Ring Gasket Dimensions and Tolerances (13)

6Pipe Sizes for Type RX Ring Gaskets Suitable for Referenced Standards (15)

7Type BX Ring Gasket Dimensions and Tolerances (16)

8Pipe Sizes for Type BX Ring Gaskets Suitable for Referenced Standards (17)

9Dimensions for Spiral-Wound Gaskets Used With ASME B16.5Flanges (18)

10Dimensions for Spiral-Wound Gaskets Used With ASME B16.47Series A Flanges (19)

11Dimensions for Spiral-Wound Gaskets Used With ASME B16.47Series B Flanges (20)

12Inner-Ring Inside Diameters for Spiral-Wound Gaskets for Use With ASME B16.5

Flanges (21)

13Inner-Ring Inside Diameters for Spiral-Wound Gaskets Used Between ASME

B16.47Series A Flanges (22)

14Inner-Ring Inside Diameters for Spiral-Wound Gaskets Used Between ASME

B16.47Series B Flanges (23)

15Minimum Pipe Wall Thickness Suitable for Use of Spiral-Wound Gaskets With

Inner Rings for ASME B16.5Flanges (24)

16Maximum Bore of ASME B16.5Flanges for Use With Spiral-Wound Gaskets (25)

17Maximum Bore of ASME B16.47Series A Flanges for Use With

Spiral-Wound Gaskets (26)

18Maximum Bore of ASME B16.47Series B Flanges for Use With

Spiral-Wound Gaskets (27)

19Color Coding and Abbreviations for Spiral-Wound Gasket Materials (28)

20Example Markings for Spiral-Wound Gaskets (29)

21Jacketed Gasket Dimensions for ASME B16.5Flanges (30)

22Jacketed Gasket Dimensions for ASME B16.47Series A Flanges (31)

23Jacketed Gasket Dimensions for ASME B16.47Series B Flanges (32)

iii

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24Abbreviations for Identifying Materials for Jacketed Gaskets (33)

25Example Markings for Jacketed Gaskets (33)

26Dimensions for Grooved Metal Gaskets With Covering Layers Used With

ASME B16.5Flanges (34)

27Dimensions for Grooved Metal Gaskets With Covering Layers Used With

ASME B16.47Series A Flanges (35)

28Dimensions for Grooved Metal Gaskets With Covering Layers Used With

ASME B16.47Series B Flanges (36)

29Color Coding and Abbreviations for Grooved Metal Gaskets With Covering Layers

Materials (37)

30Example Markings for Grooved Metal Gaskets With Covering Layers (38)

Mandatory Appendices

I Dimensions of Gaskets in U.S.Customary Units (39)

II References (61)

Nonmandatory Appendix

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A Quality System Program (62)

iv

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FOREWORD

Ring-joint gaskets and grooves probably originated in the boiler field,where they were used

in various forms for manhole covers,autoclaves,and other closures;however,it was in the oil

industry(both in the production and refining of oil)that they received the greatest recognition

and were developed into their present form.Their use expanded steadily as temperatures and

pressures were increased in steam plants.Tests examining their application in flanges and valves

were conducted as early as1928.

In June1936,the American Petroleum Institute(API)issued Tentative Standard5-G-3on Ring-

Joints for Steel Flanges and Flange Unions for use with API Tubular Goods.This standard was

known as API Specification6B,Ring-Joint Flanges.Following the acceptance of ring-joints for

flanges and valves by API and the issuance of their standard,ASA B16e on Steel Pipe Flanges

and Flanged Fittings was revised to include them,and the1939edition included standard

dimensions for a full line of ring-joint flanges based on the API standard.Development work

continued,and API formulated Standard6E,Specification for Wellhead Equipment,which

included ring-joints not covered in ASA B16e-1939.

In1949,the American Standards Association(ASA),Sectional Committee B16,Subcommittee

3,Steel Flanges and Flanged Fittings,assembled the available information on ring-joint gaskets

into a single standard.ASA approval was granted on April30,1952,with the designation

ASA B16.20-1952.

An updated version was submitted,and ASA approval was granted on April4,1955,with the

designation ASA B16.20-1955.Ring gaskets for Class900(900lb at that time)in sizes NPS26

through36were added,and ASA approval was granted on April2,1956.The standard was

reviewed in1962,and approval was granted by the ASA on April25,1963.

The standard was again reviewed and approval was granted by the American National

Standards Institute(ANSI)on April25,1973,with the designation of an American National

Standard.

API requested that ASME convert their gasket standard,API601,into an ASME American

National Standard.As a result of that request,the standard was expanded to include requirements

for spiral-wound and jacketed gaskets that were formerly listed in API601,7th edition,1988.

Also,ring-joint groove dimensions were not included,because they were included in ASME/

ANSI B16.5-1988,Pipe Flanges and Flanged Fittings,and ASME B16.47-1990,Large Diameter

Steel Flanges.

The1993edition was approved by the B16Standards Committee,and,following approval by

ASME,approval by ANSI was given on January22,1993,with the designation ASME B16.20-1993.

In the1998edition of ASME B16.20,reference standards were updated,a quality system

program annex was added,inner ring inside diameters for spiral-wound gaskets were revised,

and several editorial revisions were made.Following approval by ASME B16Subcommittee G and

the B16Main Committee,ANSI approved this American National Standard on November20,1998.

In2007,the Standard adopted metric dimensions as an independent standard to the

U.S.Customary units,and Mandatory Appendix I was added to cover dimensional tables in

U.S.Customary units.

In2012,the Standard introduced minor revisions to the material requirements for spiral-wound

gaskets,along with the tables and figures.A new chapter has been included for Grooved Metal

Gaskets With Covering Layers,and Mandatory Appendix II has also been updated to ensure

relevancy.

Following approval by B16Subcommittee G,the Standards Committee,and ASME,ANSI

approved this American National Standard on October22,2012.

v

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ASME B16COMMITTEE

Standardization of Valves,Flanges,Fittings,

and Gaskets

(The following is the roster of the Committee at the time of approval of this Standard.)

STANDARDS COMMITTEE OFFICERS

W.B.Bedesem,Chair G.A.Jolly,Vice Chair C.E.O’Brien,Secretary

STANDARDS COMMITTEE PERSONNEL

A.Appleton,Alloy Stainless Products Co.,Inc.R.W.Barnes,ANRIC Enterprises,Inc.W.

B.Bedesem,Consultant

R.M.Bojarczuk,ExxonMobil Research &Engineering Co.D.F.Buccicone,Elkhart Products Corp.

A.M.Cheta,Shell Exploration and Production Co.M.A.Clark,NIBCO,Inc.

G.A.Cuccio,Capitol Manufacturing Co.C.E.Davila,Crane Energy

D.R.Frikken,Becht Engineering Co.R.P .Griffiths,U.S.Coast Guard

SUBCOMMITTEE G —GASKETS FOR FLANGED JOINTS

D.F.Reid,Chair,VSP Technologies

a45fe2bde45c3b3566ec8b22in,Vice Chair,Exelon Nuclear

F.Huang,Secretary,The American Society of Mechanical Engineers T.Allami,Advanced Sealing and Supply Company,Inc.J.Baulch,Teadit

K.A.Benton,Consultant

R.M.Bojarczuk,ExxonMobil Research &Engineering Co.D.R.Frikken,Becht Engineering Co.C.B.Gillis,Samson Controls

vi

G.A.Jolly,Vogt Valves/Flowserve Corp.M.Katcher,Haynes International W.N.McLean,B&L Engineering

T.A.McMahon,Emerson Process Management M.L.Nayyar,Consultant

C.E.O’Brien,The American Society of Mechanical Engineers W.H.Patrick,Dow Chemical Co.R.A.Schmidt,Canadoil

H.R.Sonderegger,Fluoroseal,Inc.W.M.Stephan,Flexitallic LP

F.R.Volgstadt,Volgstadt &Associates,Inc.D.A.Williams,Southern Co.Generation

K.Guenther,Shell

D.H.Monroe,Consultant R.T.Mueller,Consultant

P .S.Petrunich,Fluid Sealing Association

M.Pollock,Graftech International Holdings,Inc.D.Reeves,Chevron

W.M.Stephan,Flexitallic LP

C.Yoder,Garlock Sealing Technologies K.Kolb,Alternate,Lamons Gasket Co.

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CORRESPONDENCE WITH THE B16COMMITTEE

General.ASME Standards are developed and maintained with the intent to represent the

consensus of concerned interests.As such,users of this Standard may interact with the Committee

by requesting interpretations,proposing revisions,and attending Committee meetings.Corre-

spondence should be addressed to:

Secretary,B16Standards Committee

The American Society of Mechanical Engineers

Two Park Avenue

New York,NY10016-5990

As an alternative,inquiries may be submitted via email to:SecretaryB16@a45fe2bde45c3b3566ec8b22.

Proposing Revisions.Revisions are made periodically to the Standard to incorporate changes

that appear necessary or desirable,as demonstrated by the experience gained from the application

of the Standard.Approved revisions will be published periodically.

The Committee welcomes proposals for revisions to this Standard.Such proposals should be

as specific as possible,citing the paragraph number(s),the proposed wording,and a detailed

description of the reasons for the proposal,including any pertinent documentation.

Interpretations.Upon request,the B16Committee will render an interpretation of any require-

ment of the Standard.Interpretations can only be rendered in response to a written request sent

to the Secretary of the B16Standards Committee.

The request for interpretation should be clear and unambiguous.It is further recommended --`,,```,,,,````-`-`,,`,,`,`,,`---

that the inquirer submit his/her request in the following format:

Subject:Cite the applicable paragraph number(s)and the topic of the inquiry.

Edition:Cite the applicable edition of the Standard for which the interpretation is

being requested.

Question:Phrase the question as a request for an interpretation of a specific requirement

suitable for general understanding and use,not as a request for an approval

of a proprietary design or situation.The inquirer may also include any plans

or drawings that are necessary to explain the question;however,they should

not contain proprietary names or information.

Requests that are not in this format will be rewritten in this format by the Committee prior

to being answered,which may inadvertently change the intent of the original request.

ASME procedures provide for reconsideration of any interpretation when or if additional

information that might affect an interpretation is available.Further,persons aggrieved by an

interpretation may appeal to the cognizant ASME Committee or Subcommittee.ASME does not

“approve,”“certify,”“rate,”or“endorse”any item,construction,proprietary device,or activity.

Attending Committee Meetings.The B16Standards Committee regularly holds meetings,which

are open to the public.Persons wishing to attend any meeting should contact the Secretary of

the B16Standards Committee.

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IMPORTANT INFORMATION CONCERNING USE OF

ASBESTOS OR ALTERNATIVE MATERIALS

Asbestos is referenced for use as a filler material in metallic gaskets.It has served as a universal

sealing material,compatible with most fluid services.It has been of extreme usefulness in minimiz-

ing fire hazards.

Certain serious adverse health effects are associated with asbestos,among them the serious

and often fatal diseases of lung cancer,asbestosis,and mesothelioma(a cancer of the chest and

abdominal linings).The degree of exposure to asbestos varies with the product and the work

practices involved.

Consult the most recent edition of the Occupational Safety and Health Administration,U.S.

Department of Labor,Occupational Safety and Health Standard for Asbestos,Tremolite,

Anthophyllite,and Actinolite,29Code of Federal Regulations Section1910.1001;the U.S.

Environmental Protection Agency National Emission Standard for Asbestos,40Code of Federal

Regulations Sections61.140through61.156;and the proposed rule by the U.S.Environmental

Protection Agency proposing labeling requirements and phased banning of asbestos products,

published at51Federal Register3738-3759(January29,1986).

There are currently in use and under development a number of substitute materials to replace

asbestos in certain applications.Manufacturers and users are encouraged to develop and use

effective substitute materials that can meet the specifications for,and operating requirements of,

the equipment to which they would apply.

Information concerning safety and health risks and proper precautions with respect to particular

materials and conditions should be obtained from one’s employer,the manufacturer or supplier

of that material,or the Material Safety Data Sheet.

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ASME B16.20-2012

SUMMARY OF CHANGES

Following approval by the B16Committee and ASME,and after public review,ASME B16.20-2012

was approved by the American National Standards Institute on October22,2012.

ASME B16.20-2012consists of editorial changes,revisions,and corrections identified by a margin

note,(12),placed next to the affected area.

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Page Location Change

1 1.1Revised

3 4.4Revised in its entirety

5Added

5Fig.1Added

Fig.2Added

6Fig.3Added

7Fig.4Added

18Table9(1)General Note(b)revised

(2)Notes(1)and(2)transposed

19Table10(1)Illustration removed

(2)General Note(b)revised

20Table11(1)Illustration removed

(2)General Note(b)revised

28Table19Revised

30Table21General Note(b)added

31Table22(1)Illustration removed

(2)General Note(b)added

32Table23(1)Illustration removed

(2)General Note(b)added

34Table26Added

35Table27Added

36Table28Added

37Table29Added

38Table30Added

39Fig.I-1Added

40Fig.I-2Added

47Table I-4(1)General Note(b)revised

(2)Notes(1)and(2)transposed

48Table I-5(1)Illustration removed

(2)General Note(b)revised

49Table I-6(1)Illustration removed

(2)General Note(b)revised

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Page Location Change

55Table I-12(1)Illustration removed

(2)General Note(b)added

56Table I-13(1)Illustration removed

(2)General Note(b)added

57Table I-14(1)Illustration removed

(2)General Note(b)added

58Table I-15Added

59Table I-16Added

60Table I-17Added

61Mandatory Appendix II Updated

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(12)

ASME B16.20-2012

METALLIC GASKETS FOR PIPE FLANGES

Ring-Joint,Spiral-Wound,and Jacketed

1SCOPE

1.1General

This Standard covers materials,dimensions,toler-

ances,and markings for metal ring-joint gaskets,spiral-

wound metal gaskets,metal-jacketed gaskets,and

grooved metal gaskets with covering layers.These gas-

kets are dimensionally suitable for use with flanges

described in reference flange standards ASME B16.5,

ASME B16.47,API Specification6A,and ISO10423.

1.2Quality Systems

Requirements relating to the product manufacturers’

quality system programs are described in

Nonmandatory Appendix A.

1.3References

Standards and specifications adopted by reference in

this Standard are shown in Mandatory Appendix II,

which is part of this Standard.

1.4Relevant Units

This Standard states values in both SI(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 parentheses or in

separate tables that appear in Mandatory Appendix I.

The values stated in each system are not exact equiva-

lents;therefore,it is required that each system of units

be used independently of the a45fe2bde45c3b3566ec8b22bining values

from the two systems constitutes nonconformance with

the Standard.

2RING-JOINT GASKETS

2.1Types

Ring-joint gaskets shall be either octagonal or oval in

cross section.

2.2Size

Ring-joint gaskets shall be identified by an R,RX,or

BX number that relates to flange size(NPS),pressure

class,and the appropriate flange standards

(ASME B16.5,ASME B16.47,API Specification6A,or

ISO10423).

1

Table1Maximum Hardness for Ring Gaskets

Maximum Hardness

Ring Gasket Material Brinell Rockwell“B”Scale

Soft iron[Note(1)]9056

Low-carbon steel12068

4–6chrome1?2Mo13072

Type41017086

Type30416083

Type31616083

Type34716083

NOTE:

(1)May be low-carbon steel,not to exceed maximum hardness of

90Brinell—56Rockwell“B.”

2.3Materials

2.3.1General.Ring-joint gasket materials,some of

which are listed in Table1,shall be selected by the user

based on suitability for the service conditions.

It is recommended that ring-joint gaskets be of a lesser

hardness than that of the mating flanges.

2.3.2Hardness.Ring-joint gaskets of materials

listed in Table1shall have a hardness equal to or less

than that shown in Table1.

2.4Marking

The outer surface of each gasket shall carry the manu-

facturer’s name or identification trademark and gasket

number prefixed by the letters R,RX,or BX,followed

by the gasket material identification.Materials shall be

identified as shown in Table2.The gasket shall also be

marked with an ASME B16.20designation.The marking

shall be applied so as not to harmfully distort the gasket

or affect the integrity of the seal.

2.5Dimensions and Tolerances

Dimensions and tolerances for ring-joint gaskets shall

be as shown in Tables3through8(Tables I-1,I-2,and

I-3of Mandatory Appendix I).

2.6Surface Finish

Types R and RX gaskets shall have a surface finish

not rougher than1.6?m(63?in.)roughness.Type BX

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ASME B16.20-2012

Table2Ring Gasket Markings

Marking Example Ring Gasket Material Identification[Note(1)]

Soft iron[Note(2)]D R51D

Low-carbon steel S R51S

4–6chrome1?2Mo F5[Note(3)]R51F5

Type410S410R51S410

Type304S304R51S304

Type316S316R51S316

Type347S347R51S347

NOTES:

(1)This number shall be preceded by the manufacturer’s name or

identification trademark.

(2)May be low-carbon steel,not to exceed maximum hardness of

90Brinell—56Rockwell“B.”

(3)F5identification designates ASTM Specification A182-72chemi-

cal composition requirements only.

gaskets shall have a surface finish not rougher than 0.8?m(32?in.)roughness.Surface finish shall pertain to the gasket-sealing surface.

2.7Identification Number

Dimensional reference identification numbers are assigned to ring-joint gaskets and shown in Tables3 through8(Tables I-1,I-2,and I-3of Mandatory Appendix I).

3SPIRAL-WOUND GASKETS

3.1Size and Class

Spiral-wound gaskets,including centering ring and inner ring(paras.3.2.4and3.2.5),are identified by flange size(NPS),pressure class,and the appropriate flange standard(ASME B16.5or ASME B16.47).

3.2Dimensions and Tolerances

3.2.1General.Dimensions and tolerances for spi-ral-wound gaskets,centering rings,and inner rings shall be in accordance with Tables9through14(Tables I-4 through I-9of Mandatory Appendix I)and as specified

in this section(see also Figs.1and I-1).

3.2.2Construction.Spiral-wound gaskets shall be constructed as alternate plies(circular layers counted as revolutions)of preformed metal windings and pliant fillers that are spirally wound.For the finished gasket, the filler shall be essentially flush with,but not below, the metal winding on both contact faces of the gasket. The metal strip in the winding shall be0.15-mm (0.006-in.)to0.23-mm(0.009-in.)thick.The filler material thickness shall be determined by the manufacturer.

3.2.3Metal Joining.The inner windings shall have a minimum of three plies of preformed metal strip without filler.The initial two plies shall have spot welds spaced

2around the inner circumference.The minimum number of welds shall be three.The maximum distance between welds shall be76mm(3.0in.).The outer windings, which shall have a minimum of three plies of preformed metal without filler,shall be spot-welded circumferen-tially with a minimum of three welds,the last of which shall be the terminal weld.

The distance of the first weld from the terminal weld shall be no greater than38mm(1.5in.).Up to four additional loose preformed metal windings beyond the terminal weld may be used to retain the gasket into the centering ring.

3.2.4Centering Ring.All spiral-wound gaskets shall be furnished assembled into a centering ring.The centering ring thickness shall be from2.97mm(0.117in.) to3.33mm(0.131in.)and suitably grooved on the inside diameter so as to retain the gasket.

3.2.5Inner Ring.Inward buckling of spiral-wound gaskets has been identified as a potential problem.Inner rings shall be furnished with all spiral-wound gaskets having PTFE(polytetrafluoroethylene)filler material. Inner rings for flexible graphite-filled,spiral-wound gas-kets shall be furnished unless the purchaser specifies otherwise.

For all filler materials,inner rings shall be furnished in spiral-wound gaskets for

(a)NPS24and larger in Class900

(b)NPS12and larger in Class1500

(c)NPS4and larger in Class2500

Inner rings are required for these gaskets due to high available bolt loads,which may result in outer ring damage.

The inner ring thickness shall be from2.97mm to 3.33mm(0.117in.to0.131in.).

Tables12through14(Tables I-7through I-9of Mandatory Appendix I)show inner ring inside diame-ters that may extend a maximum of1.5mm(0.06in.) into the flange bore under the worst combination of flange bore,eccentric installation,and tolerance. Gaskets with inner rings should be used only with socket welding,lapped,welding neck,and integral flanges.Reference Table15for minimum pipe wall thick-ness for use with gaskets with inner rings.Reference Tables16through18(Tables I-10and I-11of Mandatory Appendix I)for maximum allowable bore for use with gaskets without inner rings.

3.2.6Gasket Compression.Spiral-wound gaskets NPS1?2,NPS3?4,and NPS1in Classes150,300,and600 shall be designed so that a uniform bolt stress of172MPa (25,000psi),based on the nominal bolt root diameter, will compress the gasket to a thickness of3.30mm±0.13mm(0.130in.±0.005in.).All other gasket sizes and classes shall be designed so that a uniform bolt stress of207MPa(30,000psi)will compress the gasket to a thickness of3.30mm±0.13mm(0.130in.±0.005in.).

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