ASTM A865/A865M-23

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: A865/A865M − 06 (Reapproved 2017) A865/A865M − 23
Standard Specification for
Threaded Couplings, Steel, Black or Zinc-Coated
(Galvanized) Welded or Seamless, for Use in Steel Pipe
Joints
This standard is issued under the fixed designation A865/A865M; the number immediately following the designation indicates the year
of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.
A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope Scope*
1.1 This specification covers black or galvanized welded or seamless threaded steel couplings for use with steel pipe in NPS ⁄8
to NPS 20 [DN 6 to DN 500] inclusive (Note 1). Couplings ordered under this specification are intended for the uses outlined in
the pipe specifications referencing this specification.
NOTE 1—The dimensionless designator NPS (nominal pipe size) and DN [diameter nominal] has been substituted in this standard for such traditional terms
as nominal diameter, size, and nominal size.
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each
system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the
two systems may result in non-conformance with the standard.
1.3 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
A370 Test Methods and Definitions for Mechanical Testing of Steel Products
A700 Guide for Packaging, Marking, and Loading Methods for Steel Products for Shipment
A751 Test Methods and Practices for Chemical Analysis of Steel Products
A941 Terminology Relating to Steel, Stainless Steel, Related Alloys, and Ferroalloys
A1058 Test Methods for Mechanical Testing of Steel Products—Metric
B6 Specification for Zinc
E376 Practice for Measuring Coating Thickness by Magnetic-Field or Eddy Current (Electromagnetic) Testing Methods
2.2 ANSI Standard:
B 1.20.1 Pipe Threads
This specification is under the jurisdiction of ASTM Committee A01 on Steel, Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee A01.22
on Steel Forgings and Wrought Fittings for Piping Applications and Bolting Materials for Piping and Special Purpose Applications.
Current edition approved Sept. 1, 2017Sept. 1, 2023. Published October 2017October 2023. Originally approved in 1986. Last previous edition approved in 20122017 as
A865/A865M – 06 (2012).(2017). DOI: 10.1520/A0865_A0865M-06R17.10.1520/A0865_A0865M-23.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
A865/A865M − 23
2.3 API Standards:
5B Specification for Threading, Gaging, and Thread Inspection of Casing, Tubing, and Line Pipe Threads
5L Specification for Line Pipe
3. Terminology
3.1 Definitions of Terms—For definitions of terms used in this standard refer to:
3.1.1 Terminology A941 for general steel terminology,
3.1.2 Test Methods and Definitions A370 or Test Methods A1058 for mechanical testing of steel products terminology, and
3.1.3 Test Methods and Practices A751 for chemical analysis of steel products terminology.
4. Ordering Information
4.1 Orders for material under this specification should include the following, as required, to describe the desired material
adequately:
4.1.1 Specification number,
4.1.2 Quantity (pieces),
4.1.3 Name of material (steel pipe-couplings),
4.1.4 Method of manufacture (welded or seamless),
4.1.5 Finish (black or Type I or Type II) galvanized (see 8.19.1),
4.1.6 Size (NPS designator [DN]),
4.1.7 Standard or extra-strong classification,
4.1.8 Taper tapped-couplings for NPS 2 [DN 50] and smaller, either recessed or non-recessed, if desired, and
4.1.9 Certification (see 11.312.3), if required.
5. Process
5.1 The steel for both welded and seamless couplings shall be made by one or more of the following processes: open-hearth,
electric-furnace, or basic-oxygen.
5.2 Welded couplings NPS 3 ⁄2 [DN 90] and under may be butt-welded, unless otherwise specified. Welded couplings over NPS
3 ⁄2 [DN 90] shall be electric-welded.
6. Chemical Composition
6.1 The steel shall conform to the chemical composition requirements as specified in Table 1.
TABLE 1 Chemical Requirements
Composition, max %
Phosphorus Sulfur
All processes 0.14 0.35
Available from American Petroleum Institute (API), 1220 L. St., NW, Washington, DC 20005.
A865/A865M − 23
7. Dimensions
7.1 Coupling dimensions are listed in Tables 2-4 and Figs. 1-3.
8. Permissible Variations in Dimensions
1 1
8.1 Diameter—For couplings NPS 1 ⁄2 [DN 40] and under, the outside diameter at any point shall not vary more than ⁄64 in. [0.4
mm] over nor more than ⁄32 in. [0.8 mm] under the standard specified. For couplings NPS 2 [DN 50] and over, the outside diameter
shall not vary more than 61 % from the standard specified.
8.2 Threads—The variation of the threads shall not exceed 61 ⁄2 turns for straight tapped and 61 turn for taper tapped from
nominal as determined using gages and the gaging practices in ANSI B 1.20.1.
9. Galvanized Couplings
9.1 Galvanized couplings may be coated with zinc by either the hot-dipped (Type 1) or by the electrogalvanizing process. (Type
II) as specified by the purchaser. The zinc used for the coating shall be any grade of zinc conforming to Specification B6.
9.2 Hot-dipped galvanized couplings are coated prior to threading.
9.2.1 The minimum weight of the zinc coating on the outside surface of the hot-dipped galvanized couplings shall be equivalent
2 2
to 1.6 oz/ft [490 g/m ].
9.2.2 The weight of the zinc coating on the outside surface shall be determined by the use of a magnetic thickness gage, using
the procedure in Practice E376 or using another method that is mutually agreed upon between the purchaser and the manufacturer.
9.3 Electrogalvanized couplings are coated either before or after threading.
9.3.1 The weight of the zinc coating on the outside surface of the electrogalvanized couplings shall be equivalent to 0.18 oz/ft [55
g/m ] (see also 8.2.29.2.2)
9.4 Sampling—Samples of couplings sufficient to determine their conformance with the requirements of this specification, shall
be taken at random for each lot of couplings of the same size.
10. Threading
10.1 The coupling threads shall be in accordance with ANSI B 1.20.1. The couplings shall be applied handling tight, unless power
tight is specified on the order. Taper-tapped couplings shall be furnished on all weights of pipe NPS 2 ⁄2 [DN 65] and larger. For
sizes NPS 2 [DN 50] and smaller, it is regular practice to furnish straight-tapped couplings for standard weight pipe and
taper-tapped couplings for extra-strong and double-extra-strong pipe. Taper-tapped couplings may be specified for pipe sizes NPS
TABLE 2 Coupling Thread Dimension—Straight-Tapped (NPSC) for Standard Weight Pipe
Pitch diameter,
Outside diameter, Coupling min length,
NPS DN
in. [mm]
Threads/in. in. [mm] in. [mm]
Designator Designator
W N
L min max
1 3
⁄8 6 27 0.563 [14.3] ⁄4 [19] 0.370 [9.4] 0.377 [9.6]
1 1
⁄4 8 18 0.719 [18.3] 1 ⁄8 [29] 0.486 [12.3] 0.497 [12.6]
3 1
⁄8 10 18 0.875 [22.2] 1 ⁄8 [29] 0.622 [15.8] 0.632 [16.1]
1 1
⁄2 15 14 1.063 [27.0] 1 ⁄2 [38] 0.772 [19.6] 0.785 [19.9]
3 9
⁄4 20 14 1.313 [33.4] 1 ⁄16 [40] 0.982 [24.9] 0.996 [25.3]
1 15
1 25 11 ⁄2 1.576 [40.0] 1 ⁄16 [49] 1.231 [31.3]
...