ASTM A524 Seamless Carbon Steel Pipe
ASTM A524 – 96
Standard Specification for Seamless Carbon Steel Pipe for Atmospheric and Lower Temperatures
1. Scope
1.1 This specification covers seamless carbon steel pipe intended primarily for service at atmospheric and lower temperatures, NPS
1 ⁄ 8 to 26 inclusive, with nominal (average) wall thickness as given in ANSI B 36.10. Pipe having other dimensions may be furnished, provided such pipe complies with all other requirements of this specification. Pipe ordered to this specification shall be suitable both for welding, and for bending, flanging, and similar forming operations.
1.2 The values stated in inch-pound units are to be regarded as the standard.
NOTE 1—The dimensionless designator NPS (nominal pipe size) has been substituted in this standard for such traditional terms as “nominal diameter,” “size,” and “nominal size”.
1.3 The following hazard caveat applies to the test methods portion, Section 16, only. 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 and health practices and determine the applicability of regulatory limitations prior to use.
2. Referenced Documents
2.1 ASTM Standards:
A 530/A 530M Specification for General Requirements for Specialized Carbon and Alloy Steel Pipe
E 29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
2.2 American National Standards Institute Standard:
B36.10 Welded and Seamless Wrought Steel Pipe
3. Ordering Information
3.1 Orders for material under this specification should include the following, as required, to describe the desired material adequately:
3.1.1 Quantity (feet or number of lengths),
3.1.2 Name of material (seamless carbon steel pipe),
3.1.3 Grade (Table 1 and Table 2),
3.1.4 Manufacture (hot finished or cold drawn),
3.1.5 Size (either nominal wall thickness and weight class or schedule number, or both, or outside diameter and nominal wall thickness, ANSI B36.10),
3.1.6 Length (17),
3.1.7 Optional requirements ( Section 8 and Section 11 of Specification A 530/A 530M),
3.1.8 Test report required (Certification Section of Specification A 530/A 530M),
3.1.9 Specification designation,
3.1.10 End use of material, and
3.1.11 Special requirements.
4. General Requirements
4.1 Material furnished to this specification shall conform to the applicable requirements of the current edition of Specification A 530/A 530M unless otherwise provided herein.
5. Materials and Manufacture
5.1 Process:
5.1.1 The steel shall be killed steel made by one or more of the following processes: open-hearth, electric-furnace, or basic-oxygen.
5.1.2 The steel shall be made to fine grain practice.
5.1.3 Steel may be cast in ingots or may be strand cast.When steel of different grades are sequentially strand cast,identification of the resultant transition material is required.The producer shall remove the transition material by any established procedure that positively separates the grades.
5.1.4 Pipe NPS 1 1 ⁄ 2 and under may be either hot finished or cold drawn.
5.1.5 Unless otherwise specified, pipe NPS 2 and over shall be furnished hot finished. When agreed upon between the manufacturer and purchaser, cold-drawn pipe may be furnished.
5.2 Heat Treatment:
5.2.1 All hot-finished and cold-drawn pipe shall be reheated to a temperature above 1550 °F (845°C) and followed by cooling in air or in the cooling chamber of a controlled atmosphere furnace.
6. Chemical Composition
6.1 The steel shall conform to the chemical requirements prescribed in Table 1.
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 in Section 6. The chemical composition thus determined, or that determined from a product analysis made by the manufacturer, if the latter has not manufactured the steel, shall be reported to the purchaser or the purchaser’s representative, and shall conform to the requirements specified in Section 6.
8. Product Analysis
8.1 At the request of the purchaser, analyses of two pipes from each lot (Note 2) shall be made by the manufacturer from the finished pipe. The chemical composition thus determined shall conform to the requirements specified in Section 6.
NOTE 2—Alot shall consist of 400 lengths, or fraction thereof, for each size NPS 2 up to but not including NPS 6, and of 200 lengths, or fraction thereof, for each size NPS 6 and over.
8.2 If the analysis of one of the tests specified in 8.1 does not conform to the requirements specified in 6, analyses shall be made on additional pipe of double the original number from the same lot, each of which shall conform to requirements specified.
9. Physical Properties
9.1 Tensile Properties—The material shall conform to the requirements as to tensile properties prescribed in Table 2.
A The following table gives the computed minimum values:
Note—The above table gives the computed minimum elongation values for each 1 ⁄ 32 -in. (0.79 mm) decrease in wall thickness. Where the wall thickness lies between two values shown above, the minimum elongation value is determined by the following equation:
where:
E = elongation in 2 in. or 50 mm in % and
t = actual thickness of specimen, in. (mm).
9.2 Bending Properties:
9.2.1 For pipe NPS 2 and under, a sufficient length of pipe shall stand being bent cold through 90° around a cylindrical mandrel, the diameter of which is twelve times the nominal diameter of the pipe, without developing cracks. When ordered for close coiling, the pipe shall stand being bent cold through 180° around a cylindrical mandrel, the diameter of which is eight times the nominal diameter of the pipe, without failure.
9.2.2 For pipe whose diameter exceeds 25 in. (635 mm) and whose diameter to wall thickness ratio is 7.0 or less, bend test specimens shall be bent at room temperature through 180° without cracking on the outside of the bent portion. The inside diameter of the bend shall be 1 in. (25.4 mm). This test shall be in place of Section 10.
NOTE 3—Diameter to wall thickness ratio = specified outside diameter/nominal wall thickness.
Example: For 28 in. diameter 5.000 in. thick pipe the diameter to wall
thickness ratio = 28/5 = 5.6.
10. Flattening Test Requirements
10.1 For pipe over NPS 2, a section of pipe not less than 2 1 ⁄ 2 in. (63.5 mm) in length shall be flattened cold between parallel plates until the opposite walls of the pipe meet. Flattening tests shall be in accordance with Specification A 530, except that in the equation used to calculate the H value, the following e constants shall be used:
10.2 When low D-to-t ratio tubulars are tested, because the strain imposed due to geometry is unreasonably high on the inside surface at the 6 and 12 o’clock locations, cracks at these locations shall not be cause for rejection if the D-to-t ratio is less than 10.
11. Hydrostatic Test Requirements
11.1 Each length of pipe shall be subjected to the hydrostatic pressure, except as provided in 11.2.
11.2 When specified in the order, pipe may be furnished without hydrostatic testing and each length so furnished shall include with the mandatory marking the letters “NH.”
11.3 When certification is required by the purchaser and the hydrostatic test has been omitted, the certification shall clearly state “Not Hydrostatically Tested,” and the specification number and grade designation, as shown on the certification, shall be followed by the letters “NH.”
12. Dimensions and Weights
12.1 The dimensions and weights of plain-end pipe are included in ANSI B36.10. Sizes and wall thicknesses most generally available are listed in Appendix X1.
13. Dimensions, Weight, and Permissible Variations
13.1 Weight—The weight of any length of pipe shall not vary more than 6.5 % over and 3.5 % under that specified for pipe of Schedule 120 and lighter nor more than 10 % over and 3.5 % under that specified for pipe heavier than Schedule 120. Unless otherwise agreed upon between the manufacturer and purchaser, pipe in sizes NPS 4 and smaller may be weighed in convenient lots; pipe in sizes larger than NPS 4 shall be weighed separately.
13.2 Diameter—Variations in outside diameter shall not exceed those specified in Table 3.
13.3 Thickness—The minimum wall thickness at any point shall not be more than 12.5 % under the nominal wall thickness specified.
NOTE 4—The minimum wall thickness on inspection is shown in
Appendix X1.
14. Workmanship, Finish, and Appearance
14.1 The pipe manufacturer shall explore a sufficient number of visual surface imperfections to provide reasonable assurance that they have been properly evaluated with respect to depth. Exploration of all surface imperfections is not required but may be necessary to assure compliance with 14.2.
14.2 Surface imperfections that penetrate more than 12 1 ⁄ 2 % of the nominal wall thickness or encroach on the minimum wall thickness shall be considered defects. Pipe with such defects shall be given one of the following dispositions:
14.2.1 The defect may be removed by grinding provided that the remaining wall thickness is within specified limits.
14.2.2 Repaired in accordance with the repair welding provisions of 14.6.
14.2.3 The section of pipe containing the defect may be cut off within the limits of requirements on length.
14.2.4 Rejected.
14.3 To provide a workmanlike finish and basis for evaluating conformance with 14.2, the pipe manufacturer shall remove by grinding the following noninjurious imperfections:
14.3.1 Mechanical marks, abrasions (Note 5) and pits, any of which imperfections are deeper than 1 ⁄ 16 in. (1.58 mm).
NOTE 5—Marks and abrasions are defined as cable marks, dinges, guide marks, roll marks, ball scratches, scores, die marks, and the like.
14.3.2 Visual imperfections, commonly referred to as scabs,seams, laps, tears or slivers, found by exploration in accordance with 14.1 to be deeper than 5 % of the nominal wall thickness.
14.4 At the purchaser’s discretion, pipe shall be subject to rejection if surface imperfections acceptable under 14.2 are not scattered, but appear over a large area in excess of what is considered a workmanlike finish. Disposition of such pipe shall be a matter of agreement between the manufacturer and the purchaser.
14.5 When imperfections or defects are removed by grinding, a smooth curved surface shall be maintained, and the wall thickness shall not be decreased below that permitted by this specification. The outside diameter at the point of grinding may be reduced by the amount so removed.
14.5.1 Wall thickness measurements shall be made with a mechanical caliper or with a properly calibrated nondestructive testing device of appropriate accuracy. In case of dispute,the measurement determined by use of the mechanical caliper shall govern.
14.6 Weld repair shall be permitted only subject to the approval of the purchaser and in accordance with Specification A 530/A 530M.
14.7 The finished pipe shall be reasonably straight.
15. Number of Tests and Retests
15.1 One of either of the tests specified in 9.1 shall be made on one length of pipe from each lot (Note 2).
15.2 For pipe NPS 2 and under, the bend test specified in 9.2 shall be made on one pipe from each lot (Note 2). The bend tests specified in 9.2.2 shall be made on one end of each pipe.
15.3 The flattening test specified in 10 shall be made on one length of pipe from each lot (Note 2).
15.4 Retests shall be in accordance with SpecificationA 530 and as provided in 15.5 and 15.6.
15.5 If a specimen breaks in an inside or outside surface flaw, a retest shall be allowed.
15.6 Should a crop end of a finished pipe fail in the flattening test, one retest may be made from the broken end.
16. Test Specimens and Methods of Testing
16.1 Specimens cut either longitudinally or transversely shall be acceptable for the tension test.
16.2 Test specimens for the bend test specified in 9.2 and for the flattening tests specified in 10 shall consist of sections cut from a pipe. Specimens for flattening tests shall be smooth on the ends and free from burrs, except when made on crop ends.
16.3 Test specimens for the bend test specified in 9.2.2 shall be cut from one end of the pipe and, unless otherwise specified,shall be taken in a transverse direction. One test specimen shall be taken as close to the outer surface as possible and another from as close to the inner surface as possible. The specimens shall be either 1 ⁄ 2 by 1 ⁄ 2 in. (12.7 mm) in section or 1 by 1 ⁄ 2 in. (25.4 by 12.7 mm) in section with the corners rounded to a radius not over 1 ⁄ 16 in. (1.6 mm) and need not exceed 6 in. (152mm) in length. The side of the samples placed in tension during the bend shall be the side closest to the inner and outer surface of the pipe respectively.
17. Lengths
17.1 Pipe lengths shall be in accordance with the following regular practice:
17.1.1 The lengths required shall be specified in the order,and
17.1.2 No jointers are permitted unless otherwise specified.
17.2 If definite lengths are not required, pipe may be ordered in single random lengths of 16 to 22 ft (4.9 to 6.7 m),with 5 % 12 to 16 ft (3.7 to 4.9 m), or in double random lengths with a minimum average of 35 ft (10.7 m) and a minimum length of 22 ft with 5 % 16 to 22 ft.
18. Rejection
18.1 Each length of pipe that develops injurious defects during shop working or application operations will be rejected,and the manufacturer shall be notified. No rejections under this or any other specifications shall be marked as specified in 19 for sale under this specification except where such pipe fails to comply with the weight requirements alone, in which case it may be sold under the weight specifications with which it does comply.
19. Product Marking
19.1 In addition to the marking prescribed in Specification A 530/A 530M, the marking shall include the hydrostatic test pressure when tested or the letters “NH” when not tested, the length and schedule number, and on pipe sizes larger than NPS 4 the weight shall be given. Length shall be marked in feet and tenths of a foot, or metres to two decimal places, depending on the units to which the material was ordered, or other marking subject to agreement.
19.2 Bar Coding—In addition to the requirements in 19.1,bar coding is acceptable as a supplemental identification method. The purchaser may specify in the order a specific bar coding system to be used.
Standard Specification for Seamless Carbon Steel Pipe for Atmospheric and Lower Temperatures
1. Scope
1.1 This specification covers seamless carbon steel pipe intended primarily for service at atmospheric and lower temperatures, NPS
1 ⁄ 8 to 26 inclusive, with nominal (average) wall thickness as given in ANSI B 36.10. Pipe having other dimensions may be furnished, provided such pipe complies with all other requirements of this specification. Pipe ordered to this specification shall be suitable both for welding, and for bending, flanging, and similar forming operations.
1.2 The values stated in inch-pound units are to be regarded as the standard.
NOTE 1—The dimensionless designator NPS (nominal pipe size) has been substituted in this standard for such traditional terms as “nominal diameter,” “size,” and “nominal size”.
1.3 The following hazard caveat applies to the test methods portion, Section 16, only. 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 and health practices and determine the applicability of regulatory limitations prior to use.
2. Referenced Documents
2.1 ASTM Standards:
A 530/A 530M Specification for General Requirements for Specialized Carbon and Alloy Steel Pipe
E 29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
2.2 American National Standards Institute Standard:
B36.10 Welded and Seamless Wrought Steel Pipe
3. Ordering Information
3.1 Orders for material under this specification should include the following, as required, to describe the desired material adequately:
3.1.1 Quantity (feet or number of lengths),
3.1.2 Name of material (seamless carbon steel pipe),
3.1.3 Grade (Table 1 and Table 2),
3.1.4 Manufacture (hot finished or cold drawn),
3.1.5 Size (either nominal wall thickness and weight class or schedule number, or both, or outside diameter and nominal wall thickness, ANSI B36.10),
3.1.6 Length (17),
3.1.7 Optional requirements ( Section 8 and Section 11 of Specification A 530/A 530M),
3.1.8 Test report required (Certification Section of Specification A 530/A 530M),
3.1.9 Specification designation,
3.1.10 End use of material, and
3.1.11 Special requirements.
4. General Requirements
4.1 Material furnished to this specification shall conform to the applicable requirements of the current edition of Specification A 530/A 530M unless otherwise provided herein.
5. Materials and Manufacture
5.1 Process:
5.1.1 The steel shall be killed steel made by one or more of the following processes: open-hearth, electric-furnace, or basic-oxygen.
5.1.2 The steel shall be made to fine grain practice.
5.1.3 Steel may be cast in ingots or may be strand cast.When steel of different grades are sequentially strand cast,identification of the resultant transition material is required.The producer shall remove the transition material by any established procedure that positively separates the grades.
5.1.4 Pipe NPS 1 1 ⁄ 2 and under may be either hot finished or cold drawn.
5.1.5 Unless otherwise specified, pipe NPS 2 and over shall be furnished hot finished. When agreed upon between the manufacturer and purchaser, cold-drawn pipe may be furnished.
5.2 Heat Treatment:
5.2.1 All hot-finished and cold-drawn pipe shall be reheated to a temperature above 1550 °F (845°C) and followed by cooling in air or in the cooling chamber of a controlled atmosphere furnace.
6. Chemical Composition
6.1 The steel shall conform to the chemical requirements prescribed in Table 1.
TABLE 1 Chemical Requirements
| Element | Grades I and II, Composition, % |
| Carbon, max | 0.21 |
| Manganese | 0.90–1.35 |
| Phosphorus, max | 0.035 |
| Sulfur, max | 0.035 |
| Silicon | 0.10–0.40 |
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 in Section 6. The chemical composition thus determined, or that determined from a product analysis made by the manufacturer, if the latter has not manufactured the steel, shall be reported to the purchaser or the purchaser’s representative, and shall conform to the requirements specified in Section 6.
8. Product Analysis
8.1 At the request of the purchaser, analyses of two pipes from each lot (Note 2) shall be made by the manufacturer from the finished pipe. The chemical composition thus determined shall conform to the requirements specified in Section 6.
NOTE 2—Alot shall consist of 400 lengths, or fraction thereof, for each size NPS 2 up to but not including NPS 6, and of 200 lengths, or fraction thereof, for each size NPS 6 and over.
8.2 If the analysis of one of the tests specified in 8.1 does not conform to the requirements specified in 6, analyses shall be made on additional pipe of double the original number from the same lot, each of which shall conform to requirements specified.
9. Physical Properties
9.1 Tensile Properties—The material shall conform to the requirements as to tensile properties prescribed in Table 2.
TABLE 2 Tensile Requirements
| Wall Thicknesses | ||||
| Grade I, 0.375 in. (9.52 mm) and under | Grade II, greater than 0.375 in.(9.52 mm) | |||
| Tensile strength, psi (MPa) | 60 000–85 000(414–586) | 55 000–80 000 (380–550) | ||
| Yield strength, min, psi (MPa) | 35 000 (240) | 30 000 (205) | ||
| Longitudinal | Transverse | Longitudinal | Transverse | |
| Elongation in 2 in. or 50 mm, min %: | 30 | 16.5 | 35 | 25 |
| Basic minimum elongation for walls 5 ⁄16 in. (7.9 mm) and over in thickness, strip tests, and for all small sizes tested in full section | 22 | 12 | 28 | 20 |
| When standard round 2 in. or 50 mm gage length test specimen is used for strip tests, a deduction for each 1 ⁄ 32 in. (0.8 mm) decrease in wall thickness below 5 ⁄ 16 in. (7.9 mm) from the basic minimum elongation of the following percentage | 1.50 A | 1.00 A | .... | .... |
|
Wall Thickness |
Elongation in 2 in. or 50 mm, min, % | ||
| Grade I | |||
| in. | mm | Longitudinal | Transverse |
| 5 ⁄ 16 (0.312) | 7.94 | 30.0 | 16.5 |
| 9 ⁄ 32 (0.281) | 7.14 | 28.5 | 15.5 |
| 1 ⁄ 4 (0.250) | 6.35 | 27.0 | 14.5 |
| 7 ⁄ 32 (0.219) | 5.56 | 25.5 | .... |
| 3 ⁄ 16 (0.188) | 4.76 | 24.0 | .... |
| 5 ⁄ 32 (0.156) | 3.97 | 22.5 | .... |
| 1 ⁄ 8 (0.125) | 3.18 | 21.0 | .... |
| 3 ⁄ 32 (0.094) | 2.38 | 19.5 | .... |
| 1 ⁄ 16 (0.062) | 1.59 | 18.0 | .... |
Note—The above table gives the computed minimum elongation values for each 1 ⁄ 32 -in. (0.79 mm) decrease in wall thickness. Where the wall thickness lies between two values shown above, the minimum elongation value is determined by the following equation:
| Grade | Direction of Test | Equation |
| I | transverse | E = 32t + 6.50 |
| I | longitudinal | E = 48t + 15.00 |
where:
E = elongation in 2 in. or 50 mm in % and
t = actual thickness of specimen, in. (mm).
9.2 Bending Properties:
9.2.1 For pipe NPS 2 and under, a sufficient length of pipe shall stand being bent cold through 90° around a cylindrical mandrel, the diameter of which is twelve times the nominal diameter of the pipe, without developing cracks. When ordered for close coiling, the pipe shall stand being bent cold through 180° around a cylindrical mandrel, the diameter of which is eight times the nominal diameter of the pipe, without failure.
9.2.2 For pipe whose diameter exceeds 25 in. (635 mm) and whose diameter to wall thickness ratio is 7.0 or less, bend test specimens shall be bent at room temperature through 180° without cracking on the outside of the bent portion. The inside diameter of the bend shall be 1 in. (25.4 mm). This test shall be in place of Section 10.
NOTE 3—Diameter to wall thickness ratio = specified outside diameter/nominal wall thickness.
Example: For 28 in. diameter 5.000 in. thick pipe the diameter to wall
thickness ratio = 28/5 = 5.6.
10. Flattening Test Requirements
10.1 For pipe over NPS 2, a section of pipe not less than 2 1 ⁄ 2 in. (63.5 mm) in length shall be flattened cold between parallel plates until the opposite walls of the pipe meet. Flattening tests shall be in accordance with Specification A 530, except that in the equation used to calculate the H value, the following e constants shall be used:
0.07 for Grade I
0.08 for Grade II
0.08 for Grade II
10.2 When low D-to-t ratio tubulars are tested, because the strain imposed due to geometry is unreasonably high on the inside surface at the 6 and 12 o’clock locations, cracks at these locations shall not be cause for rejection if the D-to-t ratio is less than 10.
11. Hydrostatic Test Requirements
11.1 Each length of pipe shall be subjected to the hydrostatic pressure, except as provided in 11.2.
11.2 When specified in the order, pipe may be furnished without hydrostatic testing and each length so furnished shall include with the mandatory marking the letters “NH.”
11.3 When certification is required by the purchaser and the hydrostatic test has been omitted, the certification shall clearly state “Not Hydrostatically Tested,” and the specification number and grade designation, as shown on the certification, shall be followed by the letters “NH.”
12. Dimensions and Weights
12.1 The dimensions and weights of plain-end pipe are included in ANSI B36.10. Sizes and wall thicknesses most generally available are listed in Appendix X1.
13. Dimensions, Weight, and Permissible Variations
13.1 Weight—The weight of any length of pipe shall not vary more than 6.5 % over and 3.5 % under that specified for pipe of Schedule 120 and lighter nor more than 10 % over and 3.5 % under that specified for pipe heavier than Schedule 120. Unless otherwise agreed upon between the manufacturer and purchaser, pipe in sizes NPS 4 and smaller may be weighed in convenient lots; pipe in sizes larger than NPS 4 shall be weighed separately.
13.2 Diameter—Variations in outside diameter shall not exceed those specified in Table 3.
TABLE 3 Variations in Outside Diameter
| NPS Designator | Permissible Variations in Outside Diameter, in. (mm) | |
| Over | Under | |
| 1 ⁄ 8 to 1 1 ⁄ 2 , incl | 1 ⁄ 64 (0.4) | 1 ⁄ 32 (0.8) |
| Over 1 1 ⁄ 2 to 4, incl | 1 ⁄ 32 (0.8) | 1 ⁄ 32 (0.8) |
| Over 4 to 8, incl | 1 ⁄ 16 (1.6) | 1 ⁄ 32 (0.8) |
| Over 8 to 18, incl | 3 ⁄ 32 (2.4) | 1 ⁄ 32 (0.8) |
| Over 18 | 1 ⁄ 8 (3.2) | 1 ⁄ 32 (0.8) |
13.3 Thickness—The minimum wall thickness at any point shall not be more than 12.5 % under the nominal wall thickness specified.
NOTE 4—The minimum wall thickness on inspection is shown in
Appendix X1.
14. Workmanship, Finish, and Appearance
14.1 The pipe manufacturer shall explore a sufficient number of visual surface imperfections to provide reasonable assurance that they have been properly evaluated with respect to depth. Exploration of all surface imperfections is not required but may be necessary to assure compliance with 14.2.
14.2 Surface imperfections that penetrate more than 12 1 ⁄ 2 % of the nominal wall thickness or encroach on the minimum wall thickness shall be considered defects. Pipe with such defects shall be given one of the following dispositions:
14.2.1 The defect may be removed by grinding provided that the remaining wall thickness is within specified limits.
14.2.2 Repaired in accordance with the repair welding provisions of 14.6.
14.2.3 The section of pipe containing the defect may be cut off within the limits of requirements on length.
14.2.4 Rejected.
14.3 To provide a workmanlike finish and basis for evaluating conformance with 14.2, the pipe manufacturer shall remove by grinding the following noninjurious imperfections:
14.3.1 Mechanical marks, abrasions (Note 5) and pits, any of which imperfections are deeper than 1 ⁄ 16 in. (1.58 mm).
NOTE 5—Marks and abrasions are defined as cable marks, dinges, guide marks, roll marks, ball scratches, scores, die marks, and the like.
14.3.2 Visual imperfections, commonly referred to as scabs,seams, laps, tears or slivers, found by exploration in accordance with 14.1 to be deeper than 5 % of the nominal wall thickness.
14.4 At the purchaser’s discretion, pipe shall be subject to rejection if surface imperfections acceptable under 14.2 are not scattered, but appear over a large area in excess of what is considered a workmanlike finish. Disposition of such pipe shall be a matter of agreement between the manufacturer and the purchaser.
14.5 When imperfections or defects are removed by grinding, a smooth curved surface shall be maintained, and the wall thickness shall not be decreased below that permitted by this specification. The outside diameter at the point of grinding may be reduced by the amount so removed.
14.5.1 Wall thickness measurements shall be made with a mechanical caliper or with a properly calibrated nondestructive testing device of appropriate accuracy. In case of dispute,the measurement determined by use of the mechanical caliper shall govern.
14.6 Weld repair shall be permitted only subject to the approval of the purchaser and in accordance with Specification A 530/A 530M.
14.7 The finished pipe shall be reasonably straight.
15. Number of Tests and Retests
15.1 One of either of the tests specified in 9.1 shall be made on one length of pipe from each lot (Note 2).
15.2 For pipe NPS 2 and under, the bend test specified in 9.2 shall be made on one pipe from each lot (Note 2). The bend tests specified in 9.2.2 shall be made on one end of each pipe.
15.3 The flattening test specified in 10 shall be made on one length of pipe from each lot (Note 2).
15.4 Retests shall be in accordance with SpecificationA 530 and as provided in 15.5 and 15.6.
15.5 If a specimen breaks in an inside or outside surface flaw, a retest shall be allowed.
15.6 Should a crop end of a finished pipe fail in the flattening test, one retest may be made from the broken end.
16. Test Specimens and Methods of Testing
16.1 Specimens cut either longitudinally or transversely shall be acceptable for the tension test.
16.2 Test specimens for the bend test specified in 9.2 and for the flattening tests specified in 10 shall consist of sections cut from a pipe. Specimens for flattening tests shall be smooth on the ends and free from burrs, except when made on crop ends.
16.3 Test specimens for the bend test specified in 9.2.2 shall be cut from one end of the pipe and, unless otherwise specified,shall be taken in a transverse direction. One test specimen shall be taken as close to the outer surface as possible and another from as close to the inner surface as possible. The specimens shall be either 1 ⁄ 2 by 1 ⁄ 2 in. (12.7 mm) in section or 1 by 1 ⁄ 2 in. (25.4 by 12.7 mm) in section with the corners rounded to a radius not over 1 ⁄ 16 in. (1.6 mm) and need not exceed 6 in. (152mm) in length. The side of the samples placed in tension during the bend shall be the side closest to the inner and outer surface of the pipe respectively.
17. Lengths
17.1 Pipe lengths shall be in accordance with the following regular practice:
17.1.1 The lengths required shall be specified in the order,and
17.1.2 No jointers are permitted unless otherwise specified.
17.2 If definite lengths are not required, pipe may be ordered in single random lengths of 16 to 22 ft (4.9 to 6.7 m),with 5 % 12 to 16 ft (3.7 to 4.9 m), or in double random lengths with a minimum average of 35 ft (10.7 m) and a minimum length of 22 ft with 5 % 16 to 22 ft.
18. Rejection
18.1 Each length of pipe that develops injurious defects during shop working or application operations will be rejected,and the manufacturer shall be notified. No rejections under this or any other specifications shall be marked as specified in 19 for sale under this specification except where such pipe fails to comply with the weight requirements alone, in which case it may be sold under the weight specifications with which it does comply.
19. Product Marking
19.1 In addition to the marking prescribed in Specification A 530/A 530M, the marking shall include the hydrostatic test pressure when tested or the letters “NH” when not tested, the length and schedule number, and on pipe sizes larger than NPS 4 the weight shall be given. Length shall be marked in feet and tenths of a foot, or metres to two decimal places, depending on the units to which the material was ordered, or other marking subject to agreement.
19.2 Bar Coding—In addition to the requirements in 19.1,bar coding is acceptable as a supplemental identification method. The purchaser may specify in the order a specific bar coding system to be used.