Continuous Thread Stud, Double-End Stud, and Flange Bolting Stud (Stud Bolt) (Inch Series)

AN A MERICAN NA TIONAL S T AND ARD

ASME B18.31.2-2014

(Revision of ASME B18.31.2-2008)

ASME B18.31.2-2014

(Revision of ASME B18.31.2-2008)

Continuous Thread Stud, Double-End Stud, and Flange Bolting Stud (Stud Bolt) (Inch Series)

AN AMERICAN NA TIONAL S T AND ARD

Two Park Avenue • New York, NY • 10016 USA

Date of Issuance: October 29, 2014

This Standard will be revised when the Society approves the issuance of a new edition.

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CONTENTS

Foreword iv

Committee Roster vi

Correspondence With the B18 Committee vii

1. Introduction 1

2. Comparison With ISO Documents 1

3. Referenced Standards 1

4. Terminology 2

5. Dimensions 2

6. Body Diameter 2

7. Stud Length 2

8. Stud Ends 7

9. Thread Length 7

10. Screw Threads 7

11. Materials and Mechanical Properties 7

12. Identification Symbols 8

13. Finish 8

14. Workmanship 8

15. Straightness 8

16. Inspection and Quality Assurance 8

17. Clearance Holes 8

18. Stud Designation 8

Figure

1 Relationship of Dimensions, L and U, on Flange Bolting Studs (Stud Bolts) 2

Tables

1. Dimensions for Continuous Thread Studs 3

2. Dimensions for Clamping Type Studs 4

3. Dimensions for Tap-End Studs (1.5D Engagement) 5

4. Body Diameters for Double-End Studs 6

5. Continuous Thread and Double-End Stud Length Tolerances 7

6. Flange Bolting Stud (Stud Bolt) Length Tolerances 7

iii

FOREWORD

ASME Standards Committee B18 for the Standardization of Bolts, Nuts, Rivets, Screws, Washers, and Similar Fasteners (formerly American National Standards Committee B18) was organized in March 1922 as Sectional Committee B18 under the aegis of the American Engineering Standards Committee (later the American Standards Association, then the United States of America Standards Institute, and, as of October 6, 1969, the American National Standards Institute, Inc. [ANSI]) with the Society of Automotive Engineers (SAE) and the American Society of Mechanical Engineers (ASME) as joint sponsors.

In 1995, the SAE Ship Systems and Equipment Committee that was preparing fastener part standards for the shipbuilding industry asked ASME Committee B18 if there was an interest in developing dimensional standards for studs. At the December 1995 meeting of B18 in Atlanta, it was reported that a survey by ASME showed considerable interest in establishing a subcommit- tee to develop stud standards, and 11 representatives indicated their willingness to serve on a subcommittee. Subcommittee 31 was established, and draft SAE inch and metric stud standards were distributed for review.

The first meeting of Subcommittee 31 on studs was held in April 1996, in conjunction with the ASME B18 meetings in Chicago. Existing stud standards (IFI 136, Studs and Bolts, and IFI 528, Metric Studs and Bolts) were compared with the draft SAE standards (J2271, Part Standard for Studs — Continuous and Double End [Inch Series], and J2271M, Part Standard for Studs — Continuous and Double End [Metric]). The Subcommittee then identified the configurations to be developed along with thread sizes and diameters to be covered. It was determined to develop both inch and metric standards covering both continuously threaded and double-ended studs. A decision to develop the metric standard first was unanimously passed.

As the metric standard B18.31.1M was developed, little effort was devoted to the inch standard until 2005. In April 2005, the Subcommittee developed basic requirements for the inch studs that were similar to the metric studs, with the addition of interference-fit studs using ASME B1.12 threads. A draft was reviewed at the November 2006 meeting with a number of format changes suggested. How to define the nominal length for tap-end studs was discussed, and a motion was approved to identify the nominal length as the overall length rather than the protrusion length when installed as used in ASME B18.31.1M per ISO 225 requirements.

In November 2006, the Subcommittee decided that diameters from 1⁄4 in. to 4 in. would be covered although at the previous meeting it had been agreed to cover diameters down to Size No. 0. The nominal length for tap-end studs was again revisited without a consensus being reached.

At the April 2007 meeting, examples of both methods of identifying the nominal length of tap studs were reviewed, and it was determined to use the overall length as the nominal length as this had been the past convention for inch studs in the United States.

A draft was balloted prior to the November 2007 meeting and several disapprovals were resolved at the meeting. It was agreed that the maximum nut-end thread length would be deleted in favor of a total thread length to the last scratch, which would be the minimum thread length plus five thread pitches. As a result, thread gaging is simplified without affecting the overall suitability of the studs.

A reconsideration draft was balloted prior to the April 2008 meeting. The only disapproval was withdrawn prior to the meeting, and the Subcommittee approved several minor editorial corrections at the meeting.

ASME B18.31.2-2008 was approved by the American National Standards Institute on August 4, 2008.

In the fall of 2013, the B18.31 Subcommittee decided it was time to make some minor revisions to B18.31.2 to update its format and content to be consistent with recent revisions of other B18 standards. The technical revisions are to change the pointed ends from optional to mandatory,

iv

and to add a stud type referred to as “flange bolting stud (stud bolt).” This is a stud design that originated in the 1960s by the publication of the ASME B16.5 flange standard wherein it described the continuous-thread stud having a length designation from the first full thread on one end to the first full thread on the other end rather than the length being designated as being from end to end. This description was used for many years in general terms in ASTM A193 and A962, but never thoroughly covered by the ASME B18 standards.

This revision was approved by ANSI on August 1, 2014.

v

ASME B18 COMMITTEE

Standardization of Bolts, Nuts, Rivets, Screws, Washers, and Similar Fasteners

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

STANDARDS COMMITTEE OFFICERS

J. Greenslade, Chair

D. S. George, Vice Chair

W. H. King, Vice Chair

1. J. Gomez, Secretary

   
   

   
   

   V. Cartina, Nylok, LLC

2. A. Clever, Contributing Member, Consultant

A. P. Cockman, Ford Motor Co.

1. D. de la Garza, TSP, Inc.

2. S. George, Ramco Specialties

STANDARDS COMMITTEE PERSONNEL

M. D. Prasad, Contributing Member, Global M & F Solutions, Inc.

J. F. McCarrick, Defense Supply Center Philadelphia

J. P. Nash, Caterpillar, Inc.

S. Savoji, Contributing Member, ITW Medalist

Q. M. Smith III, Oregon Department of Transportation

C. J. Gomez, The American Society of Mechanical Engineers

J. Greenslade, Industrial Fasteners Institute

J. J. Grey, Contributing Member, Fastener Consulting Services, Inc.

A. Herskovitz, Contributing Member, Consultant

J. Hubbard, Leland-Powell Fasteners, Inc.

J. C. Jennings, Contributing Member, Naval Surface Warfare Center

W. H. King, Fastenal Co.

D. Korneffel, Contributing Member, Cadenas PARTsolutions

D. J. Soscia, General Dynamics Electric Boat Corp.

W. R. Stevens, Ramco

R. D. Strong, Doerken Corp.

W. K. Wilcox, Consultant

C. B. Williamson, Fastenal Co.

C. J. Wilson, Consultant

J. G. Zeratsky, Contributing Member, National Rivet and Manufacturing Co.

C. D. de la Garza, Chair, TSP, Inc.

T. Anderson, Vice Chair, Bay Bolt

J. F. Braden, Fasteners Unlimited

SUBCOMMITTEE 31 — STUDS, LIFTING EYES, AND BENT BOLTS

J. F. McCarrick, Defense Supply Center Philadelphia

R. B. Meade, Atrona Test Labs, Inc.

W. R. Schevey, BGM-Fastener Co., Inc.

D. A. Clever, Contributing Member, Consultant

J. Finnegan, Safety Socket, LLC

D. S. George, Ramco Specialties

J. Greenslade, Industrial Fasteners Institute

A. Herskovitz, Consultant

J. Hubbard, Leland-Powell Fasteners, Inc.

J. C. Jennings, Naval Surface Warfare Center

J. W. Lewis, Newport News Shipbuilding

G. M. Simpson, Semblex Corp.

D. J. Soscia, General Dynamics Electric Boat Corp.

W. R. Stevens, Ramco

R. D. Strong, Doerken Corp.

W. K. Wilcox, Consultant

C. B. Williamson, Fastenal Co.

1. J. Wilson, Consultant

2. Winn, Kamax

vi

CORRESPONDENCE WITH THE B18 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, B18 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 for the purpose of providing 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 B18 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 B18 Standards Committee at go.asme.org/Inquiry.

The request for an 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 may be rewritten in the appropriate 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 B18 Standards Committee regularly holds meetings and/or telephone conferences that are open to the public. Persons wishing to attend any meeting and/or telephone conference should contact the Secretary of the B18 Standards Committee. Future Committee meeting dates and locations can be found on the Committee Page at

go.asme.org/B18Committee.

vii

INTENTIONALLY LEFT BLANK

viii

ASME B18.31.2-2014

CONTINUOUS THREAD STUD, DOUBLE-END STUD, AND FLANGE BOLTING STUD (STUD BOLT) (INCH SERIES)

1. INTRODUCTION

   1. Scope

      1. This Standard covers the complete dimen- sional and general data for the following types of studs in inch dimensions:

         1. continuous thread studs

         2. double-end studs

         3. flange bolting studs (stud bolts)

         These studs are recognized as American National Standard. The following configurations are covered:

         continuous thread stud: a stud that is threaded over its complete length.

         double-end (clamping type — identical ends) stud: a stud with screw threads of the same length and configuration on each end. This type of stud serves the function of clamping two bodies together with a nut on each end.

         double-end (tap-end type) stud: a stud designed to be installed in a tapped hole and usually with different threaded lengths on each end. For the tap end of the studs, both regular unified threads and interference-fit threads are covered.

         Double-end studs of the following body diameters are covered:

         1. reduced-diameter body (see para. 6.1 for dimensions)

         2. full body (see para. 6.2 for dimensions)

         flange bolting stud (stud bolt): a threaded stud used pri- marily in applications with flanges covered by ASME B16.5, and made using ASTM A01 bolting materials.

      2. The inclusion of dimensional data in this Standard is not intended to imply that all products described are stock production items. Consumers should consult with suppliers concerning availability of products.

         
         

2. COMPARISON WITH ISO DOCUMENTS

   There is no comparable ISO standard.

3. REFERENCED STANDARDS

The following is a list of publications referenced in this Standard. Unless otherwise specified, the reference shall be to the most recent issue at the time of order placement.

ASME B1.1, Unified Inch Screw Threads (UN and UNR Thread Form)

ASME B1.3, Screw Thread Gaging Systems for Acceptability — Inch and Metric Screw Threads (UN, UNR, UNJ, M, and MJ)

ASME B1.12, Class 5 Interference-Fit Thread ASME B16.5, Pipe and Flange Fittings

ASME B18.2.8, Clearance Holes for Bolts, Screws, and Studs

ASME B18.2.9, Straightness Gage and Gaging for Bolts and Screws

ASME B18.12, Glossary of Terms for Mechanical Fasteners

ASME B18.18, Quality Assurance for Fasteners ASME Y14.5, Dimensioning and Tolerancing

Publisher: The American Society of Mechanical Engineers (ASME), Two Park Avenue, New York, NY 10016-5990; Order Department: 22 Law Drive,

P.O. Box 2900, Fairfield, NJ 07007-2900 (www.asme.org)

ASTM A193/A193M, Alloy-Steel and Stainless Steel Bolting Materials for High-Temperature Service

ASTM A320/A320M, Alloy Steel Bolting Materials for Low-Temperature Service

ASTM A354, Quenched and Tempered Alloy Steel Bolts, Studs, and Other Externally Threaded Fasteners

ASTM A380, Standard Practice for Cleaning, Descaling, and Passivation of Stainless Steel Parts, Equipment, and Systems

ASTM A437/A437M, Alloy-Steel Turbine-Type Bolting Material Specially Heat Treated for High-Temperature Service

ASTM A449, Quenched and Tempered Steel Bolts and Studs

ASTM A453/A453M, High-Temperature Bolting Materials With Expansion Coefficients Comparable to Austenitic Stainless Steels

ASTM A540/A540M, Alloy-Steel Bolting Materials for Special Applications

ASTM A1014/A1014M, Precipitation-Hardening Bolting Material (UNS N07718) for High Temperature Service

ASTM F468, Nonferrous Bolts, Hex Cap Screws, and Studs for General Use

ASTM F593, Stainless Steel Bolts, Hex Cap Screws, and Studs

ASTM F788/F788M, Surface Discontinuities of Bolts, Screws, and Studs, Inch and Metric Series

1