ASTM A512-18

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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: A512 − 17 A512 − 18
Standard Specification for
Cold-Drawn Buttweld Carbon Steel Mechanical Tubing
This standard is issued under the fixed designation A512; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope*
1.1 This specification covers cold-drawn buttweld carbon steel tubes for use as mechanical tubing.
1.2 This specification covers round, square, rectangular, and special shape mechanical tubing.
1.3 Round tube size ranges covered are outside diameters up to 3 ⁄2 in. (88.9 mm) and wall thickness from 0.035 to 0.500 in.
(0.89 to 12.70 mm).
1.4 Optional supplementary requirements are provided and, when desired, shall be so stated in the order.
1.5 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.
1.6 This product is available in various grades (Section 6 Tables 1 and 2 and conditions (Section 5).
1.7 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
A751 Test Methods, Practices, and Terminology for Chemical Analysis of Steel Products
A1040 Guide for Specifying Harmonized Standard Grade Compositions for Wrought Carbon, Low-Alloy, and Alloy Steels
2.2 Military Standards:
MIL-STD-129 Marking for Shipment and Storage
2.3 Federal Standard:
Fed. Std. No. 123 Marking for Shipments (Civil Agencies)
3. Ordering Information
3.1 Orders for material under this specification should include the following, as required, to describe the required material
adequately:
3.1.1 Quantity (feet, weight (Note 1), or number of lengths),
NOTE 1—The term “weight” is temporarily used in this specification because of established trade usage. The word is used to mean both “force” and
“mass,” and care must be taken to determine which is meant in each case (SI unit for force = newton and for mass = kilogram).
3.1.2 Name of material (buttweld carbon steel mechanical tubing),
3.1.3 Form (round, square, rectangular, special shape),
3.1.4 Condition, description and code letters (Section 5),
3.1.5 Grade, if required (Section 6),
3.1.6 Dimensions (round, Section 9 or square and rectangular, Section 10),
This specification is under the jurisdiction of ASTM Committee A01 on Steel, Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee A01.09
on Carbon Steel Tubular Products.
Current edition approved Nov. 1, 2017Sept. 1, 2018. Published November 2017September 2018. Originally approved in 1964. Last previous edition approved in 20122017
as A512 – 06 (2012).A512 – 17. DOI: 10.1520/A0512-17.10.1520/A0512-18.
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 Standardization Documents Order Desk, Bldg. 4 Section D, 700 Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.
*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
A512 − 18
A
TABLE 1 Chemical Requirements
Chemical Composition Limits, %
Grade
Phospho-
Designation
Carbon Manganese Sulfur, max
rus, max
MT 1010 0.05–0.15 0.30–0.60 0.04 0.045
MT 1015 0.10–0.20 0.30–0.60 0.04 0.045
MT X 1015 0.10–0.20 0.60–0.90 0.04 0.045
MT 1020 0.15–0.25 0.30–0.60 0.04 0.045
MT X 1020 0.15–0.25 0.70–1.00 0.04 0.045
A
Rimmed or capped steels which may be used for the above grades are
characterized by a lack of uniformity in their chemical composition, and for this
reason product analysis is not technologically appropriate unless misapplication is
clearly indicated.
A
TABLE 2 Chemical Requirements for Other Carbon Grades
Grade Chemical Composition Limits, %
Desig-
Phospho-
B
Carbon Manganese Sulfur, max
nation
rus, max
1008 0.10 max 0.30–0.50 0.040 0.045
1010 0.08–0.13 0.30–0.60 0.040 0.045
1012 0.10–0.15 0.30–0.60 0.040 0.045
1015 0.13–0.18 0.30–0.60 0.040 0.045
1016 0.13–0.18 0.60–0.90 0.040 0.045
1018 0.15–0.20 0.60–0.90 0.040 0.045
1019 0.15–0.20 0.70–1.00 0.040 0.045
1020 0.18–0.23 0.30–0.60 0.040 0.045
1021 0.18–0.23 0.60–0.90 0.040 0.045
1025 0.22–0.28 0.30–0.60 0.040 0.045
1026 0.22–0.28 0.60–0.90 0.040 0.045
1030 0.28–0.34 0.60–0.90 0.040 0.045
1035 0.32–0.38 0.60–0.90 0.040 0.045
C
1110 0.08–0.13 0.30–0.60 0.040 0.130
C
1115 0.13–0.20 0.60–0.90 0.040 0.130
C
1117 0.14–0.20 1.00–1.30 0.040 0.130
A
Rimmed or capped steels which may be used for the above grades are
characterized by a lack of uniformity in their chemical composition, and for this
reason product analysis is not technologically appropriate unless misapplication is
clearly indicated.
B
Other analyses are available.
C
Grades 1110, 1115, and 1117 shall contain 0.08 min % sulfur.
3.1.7 Length (round length, 9.2; square and rectangular length, 10.5),
3.1.8 Burr removal (Section 11),
3.1.9 Report of chemical analysis and products analysis, if required,
3.1.10 Individual supplementary requirements if required (S1 through S5),
3.1.11 Special requirements,
3.1.12 End use,
3.1.13 Specification designation,
3.1.14 Special marking (Section 15), and
3.1.15 Special packaging (Section 16).
4. Materials and Manufacture
4.1 The steel shall be made by any process.
4.2 If a specific type of melting is required by the purchaser, it shall be as stated on the purchase order.
4.3 The primary melting may incorporate separate degassing or refining, and may be followed by secondary melting, such as
electroslag or vacuum-arc remelting. If secondary melting is employed, the heat shall be defined as all of the ingots remelted from
a single primary heat.
4.4 Steel may be cast in ingots or may be strand cast. When steel of different grades is sequentially strand cast, identification
of the resultant transition material is required. The producer shall remove the transition material by an established procedure that
positively separates the grades.
4.5 Tubes shall be made by the furnace buttweld process.
4.6 Tubes shall be cold finished, either externally only (sunk) or externally and internally (mandrel drawn).
A512 − 18
5. Condition
5.1 The purchaser shall specify in the order one of the following conditions:
MD (Mandrel Drawn)—No final thermal treatment
SD (Sink Drawn)—No final thermal treatment
MDSR—Mandrel Drawn and Stress Relieved
SDSR—Sink Drawn and Stress Relieved
MDSA—Mandrel Drawn and Soft Annealed or normalized
SDSA—Sink Drawn and Soft Annealed or normalized
NORM-MD-SR—Normalized, Mandrel Drawn, and Stress Relieved
NORM-SD-SR—Normalized, Sink Drawn, and Stress Relieved
6. Chemical Composition
6.1 The steel shall conform to the requirements as to chemical composition prescribed in Table 1 or Table 2 (see Specification
A1040) and Table 3.
6.2 When a grade is ordered under this specification, supplying an alloy grade that specifically requires the addition of any
element other than those listed for the ordered grade in Table 1 or Table 2 is not permitted.
7. Heat Analysis
7.1 An analysis of each heat of steel shall be made by the steel manufacturer to determine the percentages of the elements
specified; if secondary melting processes are used, the heat analysis shall be obtained from one remelted ingot or the product of
one remelted ingot of each primary melt. The heat analysis shall conform to the requirements specified, except that where the heat
identity has not been maintained or where the analysis is not sufficiently complete to permit conformance to be determined, the
chemical composition determined from a product analysis made by the tubular manufacturer shall conform to the requirements
specified for heat analysis. When requested in the order or contract, a report of such analyses shall be furnished to the purchaser.
7.2 A report of this analysis shall be furnished only when requested on the order.
8. Product Analysis
8.1 When requested on the purchase order, a product analysis shall be made by the manufacturer. The chemical composition
thus determined shall conform to the requirements prescribed in Table 1 or Table 2 as modified by Table 3.
8.2 The product analysis limits shown for carbon are not normally applicable to the MT grades.
8.3 The number and source of samples for such product analysis shall be based on the individual heat or lot identity of one of
the following forms of material.
8.3.1 Heat Identity Maintained—One product analysis per heat on either a billet, a length of flat rolled stock, or a tube.
8.3.2 Heat Identity Not Maintained—One product analysis from one tube per 2000 ft (610 m) or less for sizes over 3 in. (76.2
mm), or one product analysis from one tube per 5000 ft (1524 m) or less for sizes under 3 in. (76.2 mm).
8.4 If the original test for product analysis fails, retests of 2 additional billets, 2 lengths of flat rolled stock, or 2 tubes shall be
made. Both retests for the elements in question shall meet the requirements of this specification; otherwise all remaining material
in the heat or lot shall be rejected, or at the option of the producer, each billet, length, flat rolled stock, or tube may be individually
tested for acceptance.
8.5 Samples for product analysis, except for spectrochemical analysis, analysis shall be taken in accordance with Practice A751,
and the composition thus determined shall correspond to the requirements in the applicable section or table.
9. Permissible Variations in Dimensions of Round Tubing
9.1 Diameter and Wall Thickness:
9.1.1 Variations in outside diameter, inside diameter, and wall thickness shall not exceed the amounts prescribed in Table 4.
TABLE 3 Tolerances for Product Analysis for Steels Shown in
Table 1
Limit, or Maximum Variation, Over Maximum Limit or
Element
of Specified Under Minimum Limit
Range, %
Under min, % Over max, %
Carbon To 0.15, incl 0.02 0.03
Over 01.5 0.03 0.04
Manganese To 0.60, incl 0.03 0.03
Over 0.60 0.04 0.04
Phosphorus . . . . . . 0.01
Sulfur . . . . . . 0.01
A512 − 18
TABLE 4 Diameter and Wall Thickness Tolerances for Round Tubing
Outside Diameter, in. (mm) Inside Diameter, in. (mm) Wall Thickness, %
Outside Diameter Range, in. (mm)
Over Under Over Under Over Under
Sunk
A
Up to ⁄2 (12.7), excl 0.004 (0.10) 0 . . . . . . 15 15
A
1 1
⁄2 to 1 ⁄2 (12.7 to 38.1), excl 0.005 (0.13) 0 . . . . . . 10 10
A
1 ⁄2 to 3 (38.1 to 76.2), incl 0.010 (0.25) 0 . . . . . . 10 10
Mandrel Drawn
Less than 0.156 (3.96) wall:
1 1 1
Up to ⁄2 (12.7), excl 0.004 (0.10) 0 0 0.010 (0.25) 12 ⁄2 12 ⁄2
B
1 1
⁄2 to 1 ⁄2 (12.7 to 38.1), excl 0.005 (0.13) 0 0 0.005 (0.13) 10 10
0.156 (3.96) wall and over:
B
1 1
⁄2 to 1 ⁄2 (12.7 to 38.1), excl 0.005 (0.13) 0 0 0.005 (0.13) 7 7
Under 0.156 (3.96) wall:
1 ⁄2 (38.1) and over 0.010 (0.25) 0 . . . 0.010 (0.25) 10 10
0.156 (3.96) wall and over:
1 ⁄2 (38.1) and over 0.010 (0.25) 0 0 0.010 (0.25) 7 7
A
Except at the weld line, where the weld pad may exceed this figure.
B
Tubes with an inside diameter under ⁄2 in. (12.7 mm) may require more than 0.005 in. (0.13 mm) inside diameter tolerance and the producer should be consulted.
9.1.2 These variations apply to round, unannealed, and stress-relieved tubing.
9.1.3 Diameter tolerance includes ovality.
9.1.4 Sink tubing is normally ordered by outside diameter and nominal wall. Mandrel-drawn tubing is normally ordered by
outside diameter and inside diameter and may be ordered by outside diameter or inside diameter and wall thickness but not by all
three dimensions.
9.2 Length—Random lengths between acceptable limits will be furnished, utilizing the full mill length. Tubing will be cut in
half if specified. Full length random tubing will have a spread not exceeding 7 ft (2.1 m). Half-length random tubing will have
a spread not exceeding 4 ft (1.2 m). Not more than 10 % of the total footage of a shipment may be furnished in lengths shorter
than the minimum specified but not less than 6 ft (1.8 m).
9.2.1 When specified, multiple lengths will be furnished and should include allowances made for the customer’s cutting tool
width and grippage. Maximum and minimum lengths may be specified with the understanding that not more than 10 % of the total
footage in a shipment may be furnished in individual multiples cut to the customer’s specifications.
9.2.2 Variations from the specified length shall not exceed the amounts prescribed in Table 5.
9.3 Straightness:
9.3.1 A round tube shall be considered straight provided that no 3-ft (0.9-m) section departs from a straight line by more than
0.030 in. (0.76 mm).
9.3.2 The straightness of round tubes shorter than 3 ft (0.9 m) shall be proportionate to 0.010 in./ft (0.8 mm/m).
9.3.3 These straightness tolerances do not apply to soft-annealed tubing nor to long lengths of small diameter tubing.
TABLE 5 Permissible Variations in Length—Round Tubing
Lengths 4 ft (1.2 m) and under—up to 2 in. (50.8 mm) ± ⁄32 in. (0.8 mm)
diameter
Lengths 4 ft (1.2 m) and under—up to 2 in. (50.8 mm) ± ⁄32 in. (0.8 mm)
diameter
Lengths 4 ft (1.2 m) and under—over 2 in. (50.8 mm) ± ⁄64 in. (1.2 mm)
diameter
Lengths 4 ft (1.2 m) and under—over 2 in. (50.8 mm) ± ⁄64 in. (1.2 mm)
diameter
Lengths 4 ft to 10 ft (1.2 to 3.0 m), incl—up to 2 in. ± ⁄64 in. (1.2 mm)
(50.8 mm) diameter
Lengths 4 ft to 10 ft (1.2 to 3.0 m), incl—up to 2 in. ± ⁄64 in. (1.2 mm)
(50.8 mm) diameter
Lengths 4 ft to 10 ft (1.2 to 3.0 m), incl—over 2 in. ± ⁄16 in. (1.6 mm)
(50.8 mm) diameter
Lengths 4 ft to 10 ft (1.2 to 3.0 m), incl—over 2 in. ± ⁄16 in. (1.6 mm)
(50.8 mm) diameter
Lengths 10 ft to 24 ft (3.0 to 7.3 m), incl—all ± ⁄8 in. (3.2 mm)
diameters
Lengths 10 ft to 24 ft (3.0 to 7.3 m), incl—all ± ⁄8 in. (3.2 mm)
diameters
A
Lengths over 24 ft (7.3 m)—all diameters ± ⁄8 in. (3.2 mm)
A 1
Plus an additional tolerance of ± ⁄16 (1.6 mm) for each 10 ft (3.0 m) or fraction
over 24 ft (7.3 m).
A512 − 18
10. Permissible Variations in Dimensions of Square and Rectangular Tubing
10.1 Outside Dimensions and Wall Thickness—Variations in largest outside dimensions across flats and wall thickness shall not
exceed the amounts prescribed in Table 6.
10.2 Corner Radii—The corners of square and rectangular tubes shall be slightly rounded inside and slightly rounded outside
consistent with wall thickness. The outside corners may be slightly flattened. The radii of corners for square and rectangular
cold-finished buttweld tubes shall be in accordance with Table 7. Special radii may be obtained.
10.3 Squareness Tolerance—Permissible variations for the side of square and rectangular tube shall be determined by the
following equation:
6b 5 c 30.006, in. mm
~ !
where:
b = tolerance for out-of-square, and
c =
...