Large Diameter Steel Flanges

NPS 26 Through NPS 60 Metric/Inch Standard

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 B16.47-2006

(Revision of ASME B16.47-1996)

Large Diameter Steel Flanges

NPS 26 Through NPS 60 Metric/Inch Standard

AN AMERICAN NA TIONAL S T AND ARD

Three Park Avenue • New York, NY 10016

Date of Issuance: May 31, 2007

The next edition of this Standard is scheduled for publication in 2011. There will be no addenda issued to this edition.

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The American Society of Mechanical Engineers Three Park Avenue, New York, NY 10016-5990

Copyright © 2007 by

THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS

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CONTENTS

Foreword v

Committee Roster vi

Correspondence With the B16 Committee vii

1. Scope 1

2. Pressure–Temperature Ratings 2

3. Component Size: Nominal Pipe Size 3

4. Marking 3

5. Materials 3

6. Dimensions 5

7. Tolerances 6

8. Pressure Testing 6

Figures

1. Welding Ends (Welding Neck Flanges, No Backing Rings) 7

2. Welding Ends (Welding Neck Flanges With Backing Rings) 8

3. Welding Ends (Welding Neck Flanges) 9

Tables

1. List of Material Specifications 10

2. List of Bolting Specifications (Applicable ASTM Specifications) 12

3. Pressure–Temperature Ratings for Group 1.1 Materials 13

4. Pressure–Temperature Ratings for Group 1.2 Materials 14

5. Pressure–Temperature Ratings for Group 1.3 Materials 15

6. Pressure–Temperature Ratings for Group 1.4 Materials 16

7. Pressure–Temperature Ratings for Group 1.5 Materials 17

8. Pressure–Temperature Ratings for Group 1.7 Materials 18

9. Pressure–Temperature Ratings for Group 1.9 Materials 19

10. Pressure–Temperature Ratings for Group 1.10 Materials 20

11. Pressure–Temperature Ratings for Group 1.11 Materials 21

12. Pressure–Temperature Ratings for Group 1.13 Materials 22

13. Pressure–Temperature Ratings for Group 1.14 Materials 23

14. Pressure–Temperature Ratings for Group 1.15 Materials 24

15. Pressure–Temperature Ratings for Group 1.17 Materials 25

16. Pressure–Temperature Ratings for Group 2.1 Materials 26

17. Pressure–Temperature Ratings for Group 2.2 Materials 27

18. Pressure–Temperature Ratings for Group 2.3 Materials 28

19. Pressure–Temperature Ratings for Group 2.4 Materials 29

20. Pressure–Temperature Ratings for Group 2.5 Materials 30

21. Pressure–Temperature Ratings for Group 2.6 Materials 31

22. Pressure–Temperature Ratings for Group 2.7 Materials 32

23. Pressure–Temperature Ratings for Group 2.8 Materials 33

24. Pressure–Temperature Ratings for Group 2.9 Materials 34

25. Pressure–Temperature Ratings for Group 2.10 Materials 35

26. Pressure–Temperature Ratings for Group 2.11 Materials 36

27. Pressure–Temperature Ratings for Group 2.12 Materials 37

28. Dimensions of Ring-Joint Facings 38

29. Permissible Imperfections in Flange Facing Finish 38

    iii

30. Dimensions of Class 150 Series A Flanges 39

31. Dimensions of Class 300 Series A Flanges 40

32. Dimensions of Class 400 Series A Flanges 41

33. Dimensions of Class 600 Series A Flanges 42

34. Dimensions of Class 900 Series A Flanges 43

35. Dimensions of Class 75 Series B Flanges 44

36. Dimensions of Class 150 Series B Flanges 45

37. Dimensions of Class 300 Series B Flanges 46

38. Dimensions of Class 400 Series B Flanges 47

39. Dimensions of Class 600 Series B Flanges 48

40. Dimensions of Class 900 Series B Flanges 49

41. Flange Bolting Dimensional Recommendations 50

    Mandatory Appendices

    
    

    I	Pressure–Temperature Ratings and Dimensional Data for Classes 75, 150, 300,
    	400, 600, and 900 Flanges in U.S. Customary Units ...............................	51
    II	Quality System Program ..........................................................	92
    III	References ........................................................................	93

    Nonmandatory Appendices

    1. Methods Used for Establishing Pressure–Temperature Ratings 95

    2. Gaskets (Other Than Ring-Joint) 99

iv

FOREWORD

In November 1980, a task force was appointed within Subcommittee C of the American National Standards (ANSI) B16 Committee to develop a standard for pipe flanges in size NPS 26 through NPS 48. Every attempt was made to standardize those dimensions that existed within the industry for the materials covered by ANSI B16.5.

Prompted by suggestions received from committee members, the task force was authorized to increase the size range to NPS 60. The first draft was developed in December 1982 to include Class 75 through Class 1500 for the size range NPS 26 through NPS 60. Flange dimensions were based on the Manufacturers Standardization Society Standard Practice (MSS SP) 44 flanges, except for Class 75 flanges that are ANSI/API 605 flanges.

At the request of the American Petroleum Institute (API), flange dimensions, in accordance with the API Standard 605, were included in the subsequent drafts. Class 1500 flanges were deleted due to a lack of interest in using large size flanges in that pressure–temperature rating. The API-605 flanges for Class 150 and 300 and for sizes NPS 36 and smaller for classes higher than Class 300 are not compatible with the MSS SP-44 flanges. Thus, the MSS SP-44 flanges are designated as Series A flanges and the API-605 flanges are designated as Series B flanges in this Standard. Materials covered in this Standard are as in ANSI B16.5, except nickel base alloys are

excluded. Pressure–temperature ratings are in accordance with ANSI B16.5.

In 1982, American National Standards Committee B16 was reorganized as the American Society of Mechanical Engineers (ASME) B16 Committee operating under procedures accredited by ANSI. Following approval by the Standards Committee and ASME, approval as an American National Standard was given by ANSI on June 12, 1990.

The 1996 Edition allowed flanges marked with more than one material grade or specification, revised flange face finish requirements, revised pressure–temperature ratings for several material groups, added permissible flange facing imperfections, added blind flanges for Series B flanges, and included several other revisions. Following approval by the Standards Committee and ASME, Boiler and Pressure Vessel Committee, ANSI approved the previous edition as an American National Standard on October 3, 1996 with the new designation ASME B16.47-1996.

This 2006 Edition is presented in metric units, as primary units, with U.S. Customary units in either parenthetical or separate forms. Mandatory Appendix I has been provided after the main text for convenience to cover ratings and dimensions in U.S. Customary units. Inch dimension bolt holes were retained for flanges manufactured to metric dimensions to avoid fit up problems. Development of metric dimensions was done to reflect the intended precision of the dimension rather than by numerical conversion. For some materials pressure–temperature ratings have been revised to reflect revisions to material strength properties (tensile and yield) listed in the ASME Boiler and Pressure Vessel Code, Section II. Some materials have been assigned to different rating tables in order to minimize changes to ratings for commonly used materials.

All requests for interpretation or suggestions for revisions should be sent to the Administrative Secretary B16, The American Society of Mechanical Engineers, Three Park Avenue, New York, NY 10016-5990. As an alternative, inquiries may be submitted via e-mail to: SecretaryB16@asme.org. ASME B16.47-2006 was approved by the American National Standards Institute on

November 6, 2006.

v

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

H. R. Sonderegger, Chair

M. L. Nayyar, Vice Chair

U. D’Urso, Secretary

R. W. Barnes, Anric Enterprises, Inc.

STANDARDS COMMITTEE PERSONNEL

M. Katcher, Haynes International

W. B. Bedesem, ExxonMobil Research and Engineering Co.

D. A. Buccicone, Elkhart Products Corp.

M. A. Clark, Nibco, Inc.

U. D’Urso, The American Society of Mechanical Engineers

1. E. Floren, Mueller Co.

2. R. Frikken, Becht Engineering

G. G. Grills, U.S. Coast Guard

M. L. Henderson, Forgital USA

G. A. Jolly, Vogt Valves/Flowserve Corp.

W. N. McLean, Newco Valves

T. A. McMahon, Fisher Controls International, Inc.

M. L. Nayyar, Bechtel Power Corp.

J. D. Page, U.S. Nuclear Regulatory Commission

R. A. Schmidt, Trinity-Ladish

H. R. Sonderegger, Anvil International, Inc.

W. M. Stephan, Flexitallic, L.P.

T. F. Stroud, Ductile Iron Pipe Research Association

D. A. Williams, Southern Company Services

SUBCOMMITTEE C — STEEL FLANGES AND FLANGED FITTINGS

M. L. Nayyar, Chair, Bechtel Power Corp.

U. D’Urso, Secretary, The American Society of Mechanical Engineers

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

W. B. Bedesem, ExxonMobil Research and Engineering Co.

R. Chakravarti, Foster Wheeler USA Corp.

C. E. Davila, Crane Valves

B. Dennis, Kerkau Manufacturing

J. P. Ellenberger, WFI International

D. R. Frikken, Becht Engineering

M. L. Henderson, Forgital USA

C. L. Henley, Taylor Forge Engineered Systems, Inc.

R. E. Johnson, Consultant

M. Katcher, Haynes International

R. Koester, The William Powell Co.

W. N. McLean, Newco Valves

W. H. Patrick, The Dow Chemical Co.

T. V. Ramakrishnan, Forged Vessel Connections

T. C. Rentschler, Solutia Inc.

R. A. Schmidt, Trinity-Ladish

J. P. Tucker, FlowServe

M. M. Zaidi, Jacobs Engineering

vi

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, and attending Committee meetings. Corre- spondence should be addressed to:

Secretary, B16 Standards Committee

The American Society of Mechanical Engineers Three Park Avenue

New York, NY 10016-5990

As an alternative, inquiries may be submitted via e-mail to: SecretaryB16@asme.org.

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 B16 Committee 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 B16 Standards 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, which 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 B16 Standards Committee regularly holds meetings, which are open to the public. Persons wishing to attend any meeting should contact the Secretary of

the B16 Standards Committee.

vii

viii

ASME B16.47-2006

LARGE DIAMETER STEEL FLANGES

NPS 26 THROUGH NPS 60 METRIC/INCH STANDARD

1. SCOPE

   1. General

      This Standard covers pressure–temperature ratings, materials, dimensions, tolerances, marking, and testing for pipe flanges in sizes NPS 26 through NPS 60. Included here are flanges with rating class designations 75, 150, 300, 400, 600, and 900 with requirements given in both SI (metric) and U.S. Customary units, with diam- eter of bolts and flange bolt holes expressed in inch units.

      This Standard is limited to

      1. flanges made from cast or forged materials

      2. blind flanges made from cast, forged, or plate materials (see Tables 1 and 2)

         Also, included in this Standard are requirements and recommendations regarding flange bolting, flange gas- kets, and flange joints.

         
         

   2. Flange Series

      This Standard provides two series of flange dimen- sions. Series A specifies flange dimensions for general use flanges. Series B specifies flange dimensions for com- pact flanges that, in most cases, have smaller bolt circle diameters than Series A flanges. These two series of flanges are, in general, not interchangeable. The user should recognize that some flanged valves, equipment bolted between flanges, and flanged equipment may be compatible with only one series of these flanges.

      
      

   3. References

      Codes, standards, and specifications, containing pro- visions to the extent referenced herein, constitute requirements of this Standard. These reference docu- ments are listed in Mandatory Appendix III.

      
      

   4. Time of Purchase, Manufacture, or Installation

      The pressure–temperature ratings in this Standard are applicable upon its publication to all flanges within its scope that otherwise meet its requirement. For unused flanges maintained in inventory, the manufacturer of the flange may certify conformance to this Edition, provided that it can be demonstrated that all requirements of this Edition have been met. Where such components were installed in accordance with the pressure–temperature

      ratings of an earlier edition of this Standard, those rat- ings are applicable, except as may be governed by the applicable code or regulation.

      
      

   5. User Accountability

      This Standard cites responsibilities that are to be assumed by the flange user in the areas of, for example

      1. application

      2. installation

      3. system pressure testing

      4. operation

      5. material selection

         
         

   6. Quality Systems

      Requirements relating to the product manufacturer’s Quality System Program are described in Mandatory Appendix II.

      
      

   7. Relevant Units

      This Standard states values in both SI (metric) and

      U.S. Customary units. As an exception, diameter of bolts and flange bolt holes are expressed in inch units only. 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. The values stated in each system are not exact equivalents; therefore, it is required that each system of units be used indepen- dently of the other. Except for diameter of bolts and flange bolt holes, combining values from the two sys- tems constitutes nonconformance with the Standard.

      
      

   8. Service Conditions

      Criteria for selection of materials suitable for particu- lar fluid service are not within the scope of this Standard.

      
      

   9. Convention

      For the purpose of determining conformance with this Standard, the convention for fixing significant digits where limits, maximum and minimum values are speci- fied, shall be rounded as defined in ASTM Practice E 29. This requires that an observed or calculated 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 mea- surement.

      
      

      1

      ASME B16.47-2006

      
      

   10. Denotation

       1. Pressure Rating Designation. Class, followed by a dimensionless number, is the designation for pressure–temperature ratings (i.e., class 75, class 150, class 300, class 400, class 600, class 900).

       2. Size. NPS, followed by a dimensionless number, is the designation for nominal flange size. NPS is related to the reference nominal diameter, DN, used in international and other standards. For the sizes cov- ered in this Standard, the relationship is: DN p 25 NPS.

       
       

2. PRESSURE–TEMPERATURE RATINGS

   1. General

      Pressure–temperature ratings are maximum allow- able working gage pressures, in bar units, at the temper- atures in degrees Celsius shown in Tables 3 through 27 for the applicable material and class designation. Tables I-1 through I-25 of Mandatory Appendix I lists pressure–temperature ratings using psi units for pres- sure at the temperature in degrees Fahrenheit. For inter- mediate temperatures, linear interpolation is permitted. Interpolation between class designations is not per- mitted.

   2. Flanged Joints

      A flanged joint is composed of separate and indepen- dent, although interrelated, components: the flanges, the gasket, and the bolting, which are assembled by another influence, the assembler. Proper controls must be exer- cised in the selection and application for all of these elements to attain a joint that has acceptable leak tight- ness. Assembly and tightening techniques, such as con- trolled bolt tightening, are described in ASME PCC-1.

   3. Ratings of Flanged Joints

1. Basis. Pressure–temperature ratings apply to flanged joints that conform to the limitations on bolting in para. 5.3 and on gaskets in para. 5.4, and which are made up in accordance with good practice for alignment and assembly (see para. 2.2). Use of these ratings for flanged joints not conforming to these limitations is the responsibility of the user.

2. Mixed Flanged Joints. If the two flanges in a flanged joint do not have the same pressure–temperature rating, the rating of the joint at any temperature is the lower of the two flange ratings at that temperature.

1. Rating Temperature

   The temperature shown for a corresponding pressure rating is the temperature of the pressure containing shell of the component. In general, this temperature is the same as that of the contained fluid. 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 regu- lations. For any temperature below −29°C (−20°F) the rating shall be no greater than the rating shown for

   −29°C (−20°F). See also para. 2.5.3.

   
   

2. Temperature Considerations

   1. General. Use of flanges at either high or low temperatures shall take into consideration the risk of joint leakage due to forces and moments developed in the connected piping or equipment. Provisions in paras. 2.5.2 and 2.5.3 are included as advisory with the aim of lessening these risks.

   2. High Temperature. Application at tempera- tures 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 tempera- tures above 200°C (400°F) for Classes 75 and 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 and/or severe thermal gradients.

   3. Low Temperature. Some of the materials listed in Tables 1 and 2, notably some carbon steels, may undergo a decrease in ductility when used at low tem- peratures to such an extent as to be unable to safely resist shock loading, sudden changes of stress, or high stress concentration. Some codes or regulations may require impact testing for applications even where tem- peratures are higher than −29°C (−20°F). When such requirements apply, it is the responsibility of the user to ensure these requirements are communicated to the manufacturer prior to the time of purchase.

      
      

3. System Pressure Testing

   Flanged joints may be subjected to system pressure 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.

   
   

4. Welding Neck Flanges

   1. Maximum Bore Size. Ratings for welding neck flanges covered by this Standard are based upon their hubs at the welding end having a thickness at least equal to that calculated for pipe having a 276 MPa (40,000 psi) specified minimum yield strength. In order to assure adequate flange hub thickness for flange sizes NPS 26 and larger, the bore of a welding neck flange, dimension B as shown in Figs. 1 and 2, shall not exceed Bmax deter- mined as follows:

2