ASTM B743-23

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: B743 − 12 (Reapproved 2020) B743 − 23
Standard Specification for
Seamless Copper Tube in Coils
This standard is issued under the fixed designation B743; 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*
1.1 This specification establishes the requirements for seamless copper tube in coils, suitable for use in refrigeration and air
conditioning or other uses, such as oil lines and gasoline lines.
1.2 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only and are not considered standard.
1.3 The tube shall be produced of the following coppers. Unless otherwise specified, tubes made from any one of these coppers
may be supplied:coppers:
Copper Alloy Previously Used
UNS No. Designation Type of Copper
A
C10200 OF Oxygen-free without residual deoxidants
A
C10300 . Oxygen-free, extra low phosphorus
A
C10800 . Oxygen-free, low phosphorus
C12000 DLP Phosphorized, low residual phosphorus
C12200 DHP Phosphorized, high residual phosphorus
A
See Classification B224.
1.4 The following safety hazards caveat pertains to the test method portion, Section 17, of this specification. This standard does
not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard
to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior
to use.
1.5 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:
B153 Test Method for Expansion (Pin Test) of Copper and Copper-Alloy Pipe and Tubing
B170 Specification for Oxygen-Free Electrolytic Copper—Refinery Shapes
B193 Test Method for Resistivity of Electrical Conductor Materials
This specification is under the jurisdiction of ASTM Committee B05 on Copper and Copper Alloys and is the direct responsibility of Subcommittee B05.04 on Pipe and
Tube.
Current edition approved Oct. 1, 2020April 1, 2023. Published October 2020May 2023. Originally approved in 1985. Last previous edition approved in 20122020 as
B743 – 12.B743 – 12 (2020). DOI: 10.1520/B0743-12R20.10.1520/B0743-23.
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.
*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
B743 − 23
B224 Classification of Coppers
B251 Specification for General Requirements for Wrought Seamless Copper and Copper-Alloy Tube (Metric) B0251_B0251M
B577 Test Methods for Detection of Cuprous Oxide (Hydrogen Embrittlement Susceptibility) in Copper
B601 Classification for Temper Designations for Copper and Copper Alloys—Wrought and Cast
B846 Terminology for Copper and Copper Alloys
E2B950 Methods of Preparation of Micrographs of Metals and Alloys (Including Recommended Practice for Photography As
Applied to Metallography); Replaced by E 883Guide for Editorial Procedures and Form of Product Specifications for Copper
and Copper Alloys (Withdrawn 1983)
E3 Guide for Preparation of Metallographic Specimens
E8/E8M Test Methods for Tension Testing of Metallic Materials
E18 Test Methods for Rockwell Hardness of Metallic Materials
E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
E53 Test Method for Determination of Copper in Unalloyed Copper by Gravimetry (Withdrawn 2022)
E62 Test Methods for Chemical Analysis of Copper and Copper Alloys (Photometric Methods) (Withdrawn 2010)
E112 Test Methods for Determining Average Grain Size
E243 Practice for Electromagnetic (Eddy Current) Examination of Copper and Copper-Alloy Tubes
E255 Practice for Sampling Copper and Copper Alloys for the Determination of Chemical Composition (Withdrawn 2023)
E2575 Test Method for Determination of Oxygen in Copper and Copper Alloys by Inert Gas Fusion
3. General Requirements
3.1 The following sections of Specification B251 constitute a part of this specification:
3.1.1 Sampling,
3.1.2 Number of tests and retests,
3.1.3 Dimensions and permissible variations,
3.1.4 Test specimens, and
3.1.5 Significance of numerical limits.
3.2 In addition, when a section with a title identical to those referenced in 3.1 appears in this specification, it contains additional
information that supplements those appearing in Specification B251. In case of conflict, this specification shall prevail.
4. Terminology
4.1 Definitions—For the definitions of terms related to copper and copper alloys, refer to Terminology B846.
4.2 Definitions of Terms Specific to This Standard:
4.2.1 level or traverse wound, adj—coil in which the turns are wound into layers parallel to the axis of the coil such that successive
turns in a given layer are next to one another (sometimes called “helical coil”).
TABLE 1 Chemical Requirements
Composition, %
Element Copper Alloy UNS No.
A
C10200 C10300 C10800 C12000 C12200
B
Copper, min 99.95 . . 99.90 99.9
Copper + phosphorus, min . 99.95 99.95 . .
Phosphorus . 0.001–0.005 0.005–0.012 0.004–0.012 0.015–0.040
A
Oxygen in C10200 shall be 10 ppm max.
B
Silver counting as copper.
The last approved version of this historical standard is referenced on www.astm.org.
B743 − 23
4.2.2 single layer flat, adj—coil in which the product is spirally wound into a single disk-like layer (sometimes called “pan-cake
coil” or “single layer spirally wound coil”).
4.2.3 double layer flat, adj—coil in which the product is spirally wound into two connected disk-like layers such that one layer
is on top of the other (sometimes called “double layer pan-cake coil” or “double layer spirally wound coil”).
5. Ordering Information
5.1 Include the following information specified choices when placing orders for product under this specification, as applicable:
5.1.1 ASTM designation and year of issue;
5.1.2 Copper UNS No. (for example, C12200), if required (see C12200);1.3 and Table 1);
5.1.3 Temper (see Section 8);
5.1.4 Dimensions, diameter, and wall thickness. Dimensional tolerances, if other than those included in this specification, are
required;
5.1.5 How furnished: Straight lengths or coils;
5.1.6 Length Quantity: Total weight or total length or number of pieces of each size (see 14.1 and Table 2);
5.1.7 Type of coil (see coil;4.2); and
5.1.8 Total quantity of each item.Product purchased for agencies of the U.S. Government, it shall conform to the Supplementary
Requirements as defined herein.
5.2 The following options are available and and, when required, shall be specified at the time of placing the order, when
required:order:
5.2.1 Embrittlement test (see 13.3),
5.2.2 Refrigeration or air-conditioning grade Cleanness Test (see 13.4),
5.2.3 If coil ends are to be sealed (see 13.4.1.1),
5.2.4 Eddy-current test (see 13.1.1),
5.2.5 Expansion test (see 12.1.1),
5.2.6 Electrical resistivity requirement (see 10.1),
5.2.7 Certification (see Section 21),
5.2.8 Mill test Test report (see Section 22).),
5.2.9 Product certified for ASME Boiler and Pressure Code Applications (see Section 21), and
TABLE 2 Coil Length Tolerances (Specific Lengths)
Shortest Permissible
Tube Outside Diameter, in. Maximum Permissible Weight of
Nominal Length, ft (m) Length, % of Nominal Tolerance All Plus ft (m)
(mm) Ends, % of Lot Weight
Length
All sizes Up to 100 (30.5), incl 100 0 1 (0.3)
All sizes Over 100 (30.5) 40 20 . . .
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TABLE 3 Mechanical Property Requirements of Drawn-Temper and Annealed-Temper Tube
Rockwell Hardness
B
Wall Thickness, Tensile Strength Min, Elongation in 2 in.,
Yield Strength Min,
Temper Designation Scale Value A
A
ksi (MPa)
in. (mm) ksi (MPa) min %
H58 Less than 0.020 N/A N/A 36 (250) 30 (205) N/A
C
0.020 and over 30T 30 min 36 (250) 30 (205) N/A
O50 Less than 0.015 N/A N/A 30 (205) 9 (62) 40
C
0.015 to 0.035 15T 65 max 30 (205) 9 (62) 40
(0.381 to 0.889)
C
Over .035 F 55 max 30 (205) 9 (62) 40
(0.889)
O60 Less than 0.015 N/A N/A 30 (205) 6 (40) 40
C
0.015 to 0.035 15T 60 max 30 (205) 6 (40) 40
(0.381 to 0.889)
C
Over 0.35 F 50 max 30 (205) 6 (40) 40
(0.889)
A
ksi = 1000 psi.
B
Yield strength to be determined at 0.5 % extension under load.
C
Rockwell hardness values apply to tubes having an inside diameter of ⁄16 in. (7.92 mm) or over, and Rockwell hardness test shall be made on the inside surface of the
tube. When suitable equipment is not available for determining the specific Rockwell hardness, other Rockwell scales and values may be specified subject to agreement
between the purchaser and supplier.
5.2.10 Heat identification or traceability.
6. Materials and Manufacture
6.1 Material:
6.1.1 The material of manufacture shall be cast a form (cast billet, bar, tube, and so forth etc.) of Copper Alloys Nos. C10200,
C10300, C10800, C12000, or C12200 and of such purity and soundness as to be suitable for processing in to into the product
prescribed herein.
6.1.2 In the event When specified in the contract or purchase order that heat identification or traceability is required, the purchaser
shall specify the details desired.
NOTE 1—Due to the discontinuous nature of the processing of castings into wrought products, it is not always practical to identify a specific casting
analysis with a specific quantity of finished material.
6.2 Manufacture:
6.2.1 The product shall be manufactured by such hot and cold working processes neededworking, cold working, and annealing
processes as to produce a homogenous, uniform wrought structure in the finished product.
6.2.1.1 The product shall be cold drawn to the finish size and wall thickness.
6.2.1.2 When the cold-drawn cold drawn temper is required, the final drawing operation shall be such as to meet the temper
properties specified.
6.2.1.3 When the annealed temper is required, the tube shall be annealed after the final cold draw to meet the temper properties
specified.
7. Chemical Composition
7.1 The material shall conform to the compositional requirements listed in Table 1 for the copper UNS No. designation specified
in the ordering information.
7.1.1 Results of analysis on a product (check) sample shall conform to the composition requirements within the permitted
analytical variance specified in Table 1.
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7.2 These compositional limits do not preclude the presence of other elements. By agreement between the manufacturer and
purchaser, limits may be established and analysis required for unnamed elements.
8. Temper
8.1 The standard tempers for products described in this specification are given in Table 3.
8.2 H (Drawn) Temper—The temper of drawn tube shall be designated as H58 (drawn, general purpose).
8.3 O (Annealed) Temper—The temper of annealed tube shall be designated as 050 (light anneal) and 060 (soft anneal). Tempers
are defined in Classification B601.
9. Grain Size for Annealed Tempers
9.1 Grain size shall be the standard requirement for all product in the annealed tempers.
9.2 Acceptance or rejection based upon grain size shall depend only on the average grain size of a test specimen taken from each
of two sample portions, and each specimen shall be within the limits prescribed in Table 4 when determined in accordance with
Test Methods E112.
9.3 Upon agreement between the manufacturer and the purchaser, special grain size ranges (other than standard O50 and O60) may
be designated to facilitate fabrication etc. If the desired range spans both O50 and O60 designations, the O60 yield strength and
the O50 hardness limits will apply.
10. Physical Property Requirements
10.1 Electrical Resistivity Requirement—When specified in the contract or purchase-order, the product Product ordered for
electrical conductor application produced from Copper UNS No. C10200, C10300, or C12000 shall conform to the electrical mass
resistivity, Ω.g/mresistivity prescribed in Table 5 for the specified copper and temper when tested in accordance with Test Method
B193.
11. Mechanical Property Requirements
11.1 Tensile and Yield Strength—The product shall conform to the requirements in Table 3 for the specified temper.
11.2 Rockwell Hardness:
11.2.1 For product of the H58 temper andtemper, the Rockwell hardness values are given for reference purposes only.
11.2.2 For product of the O (annealed) temper, the product shall conform to the Rockwell hardness values contained in Table 3.
TABLE 4 Grain Size of Annealed Tempers
Temper Average Grain Size, mm
O60 0.040 min
O50 0.040 max
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TABLE 5 Resistivity (·g/m ) of Copper UNS No.
NOTE 1—Refer to Appendix X1 for the International Annealed Copper
Standard (IACS) electrical conductivity equivalents.
Temper C10200 C10300 C12000
O50, O60 0.153 28 0.156 14 0.170 31
H58 0.15737 0.159 40 0.174 18
12. Performance Requirements
12.1 Expansion Requirement:
12.1.1 When specified in the contract or purchase order, tube Tube furnished in the annealed temper shall be capable of being
expanded in accordance with Test Method B153 with an expansion of the outside diameter in the following percentage:
Outside Diameter, Expansion of Outside
in. (mm) Diameter, %
0.750 (19.1) and under 40
Over 0.750 (19.1) 30
12.1.2 The expanded tube shall show no cracking or rupture visible to the unaided eye.
13. Other Requirements
13.1 Nondestructive Examination for Defects:
13.1.1 Upon agreement between the manufacturer and the purchaser, each tube shall be subjected to an eddy-current test.
13.1.2 Tubes shall be tested normally in the drawn temper; however, they may be tested in the annealed temper at the option of
the manufacturer.
13.1.3 Testing shall follow the procedures of Practice E243 except for the determination of “end effect.”
NOTE 2—End effect is that length of the tube, which travels through the coil until the testing unit, has stabilized and is able to detect flaws. The magnitude
of the spike, generated when an end passes through the test coils is such that it disrupts testing momentarily.
13.1.4 Unless otherwise agreed upon between the manufacturer, or supplier, and the purchaser, the manufacturer shall have the
option of calibrating the test equipment using either notches or drilled holes. If agreement cannot be reached, drilled holes shall
be used.
13.1.4.1 Notch-depth Unless otherwise agreed upon between the manufacturer, or supplier, and the purchaser, notch-depth
standards rounded to the nearest 0.001 in. (0.025 mm) shall be 22 % (max) of the nominal bottom-wall thickness.
13.1.4.2 Drilled-hole standards shall be 0.025 in. 0.025 in. (0.635 mm) diameter (max.) for tubes up to and including ⁄4 in. in.
(19.05 mm) specified diameter and 0.031 in. (0.785 mm) (0.785 mm) max. diameter for tubes over ⁄4 in. in. (19.05 mm) specified
diameter. Hole diameter tolerance is +0.001 in.
13.1.5 Tubes that do not actuate the signaling device on the eddy-current tester shall be conside
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