Metallic Gaskets for Pipe Flanges

AN A MERICAN NA TIONAL S T AND ARD

ASME B16.20-2017

(Revision of ASME B16.20-2012)

ASME B16.20-2017

(Revision of ASME B16.20-2012)

Metallic Gaskets

for Pipe Flanges

AN AMERICAN NATIONAL STANDARD

Date of Issuance: December 29, 2017

The next edition of this Standard is scheduled for publication in 2022.

ASME issues written replies to inquiries concerning interpretations of technical aspects of this Standard. Periodically certain actions of the ASME B16 Committee may be published as Cases. Cases and interpretations are published on the ASME Web site under the Committee Pages at https://cstools.asme.org/ as they are issued.

Errata to codes and standards may be posted on the ASME Web site under the Committee Pages to provide corrections to incorrectly published items, or to correct typographical or grammatical errors in codes and standards. Such errata shall be used on the date posted.

The Committee Pages can be found at https://cstools.asme.org/. There is an option available to automatically receive an e-mail notification when errata are posted to a particular code or standard. This option can be found on the appropriate Committee Page after selecting “Errata” in the “Publication Information” section.

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 assure 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 liability. Users 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 Engineers Two Park Avenue, New York, NY 10016-5990

Copyright © 2017 by

THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS

All rights reserved Printed in U.S.A.

CONTENTS

Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v

Committee Roster vi

Correspondence With the B16 Committee vii

Important Information Concerning Use of Asbestos or Alternative Materials ix

Summary of Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . x

List of Changes in Record Number Order xi

Mandatory Appendix

I References 48

Nonmandatory Appendix

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 as 1928.

In June 1936, the American Petroleum Institute (API) issued Tentative Standard 5-G-3 on Ring-Joints for Steel Flanges and Flange Unions for use with API Tubular Goods. This standard was known as API Specification 6B, 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 the 1939 edition included standard dimensions for a full line of ring-joint flanges based on the API standard. Development work continued, and API formulated Standard 6E, Specification for Wellhead Equipment, which included ring-joints not covered in ASA B16e-1939.

In 1949, 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 approved the Standard, with the designation ASA B16.20-1952, on April 30, 1952.

On April 4,1955, ASA approved an updated edition with the designation ASA B16.20-1955. Ring gaskets for Class 900 (900 lb at that time) in sizes NPS 26 through NPS 36 were added in the next edition, which ASA approved on April 2, 1956. The Standard was again reviewed in 1962, and ASA approved it on April 25, 1963. In 1973, the Standard was revised, and the American National Standards Institute (ANSI) approved it as an American National Standard.

Following publication of the 1973 edition, API requested that ASME convert their gasket standard, API 601, 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 API 601, 7th edition, 1988. 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. The revised Standard was approved by ANSI on January 22, 1993.

Subsequent editions further expanded the Standard. In the 1998 edition, a quality system program annex was added. In the 2007 edition, metric dimensions were adopted 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. In the 2012 edition, a new chapter for grooved metal gaskets with covering layers was added.

In this 2017 edition, the entire Standard has been reorganized based on the different types of gaskets. In addition, the title of the Standard has been revised, as have multiple paragraphs, tables, and figures. Following approval by the ASME B16 Standards Committee, ANSI approved ASME B16.20-2017 as an American National Standard on October 11, 2017.

ASME B16 COMMITTEE

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

R. M. Bojarczuk, Chair

C. E. Davila, Vice Chair

C. R. Ramcharran, Secretary

STANDARDS COMMITTEE PERSONNEL

A. Appleton, Alloy Stainless Products Co., Inc.

1. E. Barker, Dezurik Water Controls

2. Barron, Ward Manufacturing

D. C. Bayreuther, Metso Automation, Flow Control Division

W. B. Bedesem, Consultant

R. M. Bojarczuk, ExxonMobil Research & Engineering Co.

A. M. Cheta, Qatar Shell GTL

M. A. Clark, NIBCO, Inc.

G. A. Cuccio, Capitol Manufacturing Co.

J. D’Avanzo, Fluoroseal Valves

C. E. Davila, Crane Energy

K. S. Felder, Valero Energy

D. R. Frikken, Becht Engineering Co.

R. B. Hai, RBH Associates

D. Hunt, Jr., Fastenal Co.

G. A. Jolly, Samshin, Ltd.

E. J. Lain, Exelon Nuclear

T. A. McMahon, Emerson Process Management

R. C. Merrick, Fluor Enterprises

M. L. Nayyar, NICE

W. H. Patrick, Dow Chemical Co.

D. Rahoi, CCM 2000

1. R. Ramcharran, The American Society of Mechanical Engineers

2. F. Reid, VSP Technologies

R. A. Schmidt, Canadoil

J. Tucker, Flowserve

F. R. Volgstadt, Volgstadt & Associates, Inc.

F. Feng, Delegate, China Productivity Center for Machinery, National Technical Committee

R. Barnes, Contributing Member, Anric Enterprises, Inc.

P. V. Craig, Contributing Member, Jomar Group

B. G. Fabian, Contributing Member, Pennsylvania Machine Works

M. Katcher, Contributing Member, Haynes International

A. G. Kireta, Jr., Contributing Member, Copper Development Association, Inc.

SUBCOMMITTEE G — GASKETS FOR FLANGED JOINTS

1. F. Reid, Chair, VSP Technologies

2. J. Lain, Vice Chair, Exelon Nuclear

C. Ramcharran, Secretary, The American Society of Mechanical Engineers

J. Baulch, Teadit North America

R. M. Bojarczuk, ExxonMobil Research & Engineering Co.

K. S. Felder, Valero Energy

P. R. Francis, Thermoseal, Inc.

D. R. Frikken, Becht Engineering Co.

K. E. Guenther, Shell

E. Jamalyaria, Flexitallic Engineering

Y. Li, Flexitallic L.P.

L. Melvin, Leader Global Technologies, Inc.

R. T. Mueller, Consultant

D. Reeves, Sealing and Bolting Technologies, LLC

M. Ruffin, Chevron

C. Yoder, Garlock Sealing Technologies

H. Azibert, Contributing Member, Camtrack, LLC

D. H. Monroe, Contributing Member, Consultant

CORRESPONDENCE WITH THE B16 COMMITTEE

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 or a case, and attending Committee meetings. Correspondence should be addressed to:

Secretary, B16 Standards Committee

The American Society of Mechanical Engineers Two Park Avenue

New York, NY 10016-5990

https://go.asme.org/Inquiry

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.

Proposing a Case. Cases may be issued to provide alternative rules when justified, to permit early implementation of an approved revision when the need is urgent, or to provide rules not covered by existing provisions. Cases are effective immediately upon ASME approval and shall be posted on the ASME Committee Web page.

Requests for Cases shall provide a Statement of Need and Background Information. The request should identify the Standard and the paragraph, figure, or table number(s), and be written as a Question and Reply in the same format as existing Cases. Requests for Cases should also indicate the applicable edition(s) of the Standard to which the proposed Case applies.

Interpretations. Upon request, the B16 Standards Committee will render an interpretation of any requirement of the Standard. Interpretations can only be rendered in response to a written request sent to the Secretary of the B16 Standards Committee.

Requests for interpreta