ASTM A450/A450M-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: A450/A450M − 21 A450/A450M − 23
Standard Specification for
General Requirements for Carbon and Low Alloy Steel
Tubes
This standard is issued under the fixed designation A450/A450M; 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 a group of requirements which, with the exceptions of 6.3 and Sections 7, 8, 19, 20, 21, 22, 23, 24,
and 25, are mandatory requirements to the following ASTM tubular product specifications:
A
Title of Specification ASTM Designation
Electric-Resistance-Welded Carbon Steel and Carbon- A178/A178M
Manganese Steel Boiler Tubes
Seamless Cold-Drawn Low-Carbon Steel Heat- A179/A179M
Exchanger and Condenser Tubes
Seamless Carbon Steel Boiler Tubes for High-Pressure A192/A192M
Service
Seamless Medium-Carbon Steel Boiler and Super- A210/A210M
heater Tubes
Electric-Resistance-Welded Carbon Steel Heat- A214/A214M
Exchanger and Condenser Tubes
Seamless and Electric-Welded Low-Alloy Steel Tubes A423/A423M
Specification for Seamless and Welded Carbon Steel A498/A498M
Heat-Exchanger Tubes with Integral Fins
Seamless Cold-Drawn Carbon Steel Feedwater Heater A556/A556M
Tubes
Seamless, Cold-Drawn Carbon Steel Tubing for Hy- A822/A822M
draulic System Service
A
These designations refer to the latest issue of the respective specifications.
1.2 One or more of Sections 6.3, 7, 8, 19, 20, 21, 22, 22.1, 24, and 25 apply when the product specification or purchase order has
a requirement for the test or analysis described by these sections.
1.3 In case of conflict between a requirement of the product specification and a requirement of this general requirement
specification only the requirement of the product specification need be satisfied.
1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units
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, 2021Nov. 1, 2023. Published November 2021November 2023. Originally approved in 1961. Last previous edition approved in 20182021
as A450/A450M – 18a.A450/A450M – 21. DOI: 10.1520/A0450_A0450M-21.10.1520/A0450_A0450M-23.
For ASME Boiler and Pressure Vessel Code applications see related Specification SA-450 in Section II of that Code.
Annual Book of ASTM Standards, Vols 01.01 and 01.04.
*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
A450/A450M − 23
are shown in brackets. 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. The
inch-pound units shall apply unless the “M” designation (SI) of the product specification is specified in the order.
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:
A178/A178M Specification for Electric-Resistance-Welded Carbon Steel and Carbon-Manganese Steel Boiler and Superheater
Tubes
A179/A179M Specification for Seamless Cold-Drawn Low-Carbon Steel Heat-Exchanger and Condenser Tubes
A192/A192M Specification for Seamless Carbon Steel Boiler Tubes for High-Pressure Service
A210/A210M Specification for Seamless Medium-Carbon Steel Boiler and Superheater Tubes
A214/A214M Specification for Electric-Resistance-Welded Carbon Steel Heat-Exchanger and Condenser Tubes
A370 Test Methods and Definitions for Mechanical Testing of Steel Products
A423/A423M Specification for Seamless and Electric-Welded Low-Alloy Steel Tubes
A498/A498M Specification for Seamless and Welded Carbon Steel Heat-Exchanger Tubes with Integral Fins
A530/A530M Specification for General Requirements for Specialized Carbon and Alloy Steel Pipe
A556/A556M Specification for Seamless Cold-Drawn Carbon Steel Feedwater Heater Tubes
A700 Guide for Packaging, Marking, and Loading Methods for Steel Products for Shipment
A751 Test Methods and Practices for Chemical Analysis of Steel Products
A822/A822M Specification for Seamless Cold-Drawn Carbon Steel Tubing for Hydraulic System Service
A941 Terminology Relating to Steel, Stainless Steel, Related Alloys, and Ferroalloys
A1047/A1047M Test Method for Pneumatic Leak Testing of Tubing
A1058 Test Methods for Mechanical Testing of Steel Products—Metric
D3951 Practice for Commercial Packaging
E92 Test Methods for Vickers Hardness and Knoop Hardness of Metallic Materials
E213 Practice for Ultrasonic Testing of Metal Pipe and Tubing
E273 Practice for Ultrasonic Testing of the Weld Zone of Welded Pipe and Tubing
E309 Practice for Eddy Current Examination of Steel Tubular Products Using Magnetic Saturation
E426 Practice for Electromagnetic (Eddy Current) Examination of Seamless and Welded Tubular Products, Titanium, Austenitic
Stainless Steel and Similar Alloys
E570 Practice for Flux Leakage Examination of Ferromagnetic Steel Tubular Products
2.2 SAE Aerospace Material Specifications:
SAE-AMS2806 Identification Bars, Wire, Mechanical Tubing, and Extrusions, Carbon and Alloy Steels and Corrosion and
Heat-Resistant Steels and Alloys
2.3 Military Standards:
MIL-STD-792 Identification Marking Requirements for Special Purpose Equipment
NAVSEA T9074-AS-GIB-010/271 Requirements for Nondestructive Testing Methods
2.4 ASME Boiler and Pressure Vessel Code:
Section IX
2.5 Steel Structures Painting Council:
SSPC-SP 6 Surface Preparation Specification No. 6 Commercial Blast Cleaning
2.6 Other Document:
SNT-TC-1A Recommended Practice for Nondestructive Personnel Qualification and Certification.
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
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 SAE International (SAE), 400 Commonwealth Dr., Warrendale, PA 15096, http://www.sae.org.
Available from Standardization Documents Order Desk, DODSSP, Bldg. 4, Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098.
Available from Naval Inventory Control Point, Code 1 Support Branch, 700 Robbins Ave., Philadelphia, PA 19111-5094.
Available from American Society of Mechanical Engineers (ASME), ASME International Headquarters, Two Park Ave., New York, NY 10016-5990, http://
www.asme.org.
Available from Society for Protective Coatings (SSPC), 40 24th St., 6th Floor, Pittsburgh, PA 15222-4656, http://www.sspc.org.
A450/A450M − 23
3.1.1 remelted heat—in secondary melting, all of the ingots remelted from a single primary heat.
3.1.2 thin-wall tube—a tube meeting the specified outside diameter and specified wall thickness set forth as follows:
Specified Outside Specified Wall Thickness
Diameter
2 in. [50.8 mm] or less 2 % or less of specified outside diameter
Greater than 2 in. [50.8 mm] 3 % or less of specified outside diameter
Any 0.020 in. [0.5 mm] or less
3.1 Other defined terms—Definitions of Terms—The definitions in Test Methods and Definitions For definitions of terms used in
A370, Test Methods, Practices, and Terminology A751, and Terminology A941 are applicable to this specification and to those
listedthis standard that are not included in 1.13.2., 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.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 remelted heat—in secondary melting, all of the ingots remelted from a single primary heat.
3.2.2 thin-wall tube—a tube meeting the specified outside diameter and specified wall thickness set forth as follows:
Specified Outside Specified Wall Thickness
Diameter
2 in. [50.8 mm] or less 2 % or less of specified outside diameter
Greater than 2 in. [50.8 mm] 3 % or less of specified outside diameter
Any 0.020 in. [0.5 mm] or less
4. Ordering Information
4.1 It is the purchaser’s responsibility to specify in the purchase order all ordering information necessary to purchase the needed
material. Examples of such information include, but are not limited to, the following:
4.1.1 Quantity (feet, metres, or number of lengths),
4.1.2 Specificiation number with grade or class, or both, as applicable and year date,
4.1.3 Manufacture (hot-finished or cold-finished),
4.1.4 Size (outside diameter and minimum wall thickness),
4.1.5 Length (specific or random),
4.1.6 Choice of testing track from the options listed in Test Methods A1058 when material is ordered to an M suffix (SI units)
product standard. If the choice of test track is not specified in the order, then the default ASTM test track shall be used as noted
in Test Methods A1058.
4.1.7 Supplementary Requirements, and
4.1.8 Additional requirements.
5. Process
5.1 The steel may be made by any process.
A450/A450M − 23
5.2 If a specific type of melting is required by the purchaser, it shall be as stated on the purchase order.
5.3 The primary melting may incorporate separate degassing or refining and may be followed by secondary melting, such as
electroslag remelting or vacuum-arc remelting.
5.4 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.
6. Chemical Composition
6.1 Samples for chemical analysis, and method of analysis shall be in accordance with Test Methods, Practices, and
TerminologyMethods and Practices A751.
6.2 Heat Analysis—If the heat analysis reported by the steel producer is not sufficiently complete for conformance with the heat
analysis requirements of the applicable product specification to be fully assessed, the manufacturer may complete the assessment
of conformance with such heat analysis requirements by using a product analysis for the specified elements that were not reported
by the steel producer, provided that product analysis tolerances are not applied and the heat analysis is not altered.
6.3 Product Analysis—Product analysis requirements and options, if any, are contained in the product specification.
7. Tensile Properties
7.1 The material shall conform to the requirements as to tensile properties prescribed in the individual specification.
7.2 The yield strength corresponding to a permanent offset of 0.2 % of the gage length or to a total extension of 0.5 % of the gage
length under load shall be determined.
7.3 If the percentage of elongation of any test specimen is less than that specified and any part of the fracture is more than ⁄4 in.
[19.0 mm] from the center of the gage length, as indicated by scribe marks on the specimen before testing, a retest shall be allowed.
8. Standard Weights
8.1 The calculated weight per unit length, based upon a specified minimum wall thickness, shall be determined by the following
equation:
W 5 C~D 2t!t (1)
where:
C = 10.69 [0.0246615],
W = weight, lb/ft [kg/m],
D = specified outside diameter, in. [mm], and
t = specified minimum wall thickness, in. [mm]
8.2 The permissible variations from the calculated weight per foot [kilogram per metre] shall be as prescribed in Table 1.
9. Permissible Variations in Wall Thickness
9.1 Variations from the specified minimum wall thickness shall not exceed the amounts prescribed in Table 2.
9.2 For tubes 2 in. [50.8 mm] and over in outside diameter and 0.220 in. [5.6 mm] and over in thickness, the variation in wall
thickness in any one cross section of any one tube shall not exceed the following percentage of the actual mean wall at the section.
The actual mean wall is defined as the average of the thickest and thinnest wall in that section.
Seamless tubes 610 %
Welded tubes 65 %
A450/A450M − 23
A
TABLE 1 Permissible Variations in Weight Per Unit Length
Permissible Variation in Weight
per Unit Length, %
Method of Manufacture
Over Under
Seamless, hot-finished 16 0
Seamless, cold-finished:
1 ⁄2 in. [38.1 mm] and under OD 12 0
Over 1 ⁄2 in. [38.1 mm] OD 13 0
Welded 10 0
A
These permissible variations in weight apply to lots of 50 tubes or more in sizes
4 in. [101.6 mm] and under in outside diameter, and to lots of 20 tubes or more in
sizes over 4 in. [101.6 mm] in outside diameter.
A
TABLE 2 Permissible Variations in Wall Thickness
Wall Thickness, %
0.095 Over Over 0.150 Over
Outside [2.4] 0.095 to 0.180 0.180,
Diameter, and to 0.150 [3.8 to [4.6]
in. [mm] Under [2.4 to 4.6], incl
3.8], incl
Over Under Over Under Over Under Over Under
Seamless, Hot-Finished Tubes
4 [101.6] and 40 0 35 0 33 0 28 0
under
Over 4 . . 35 0 33 0 28 0
[101.6]
Seamless, Cold-Finished Tubes
Over Under
1 ⁄2 [38.1] and 20 0
under
Over 1 ⁄2 [38.1] 22 0
Welded Tubes
All sizes 18 0
A
These permissible variations in wall thickness apply only to tubes, except
internal-upset tubes, as rolled or cold-finished, and before swaging, expanding,
bending, polishing, or other fabricating operations.
9.3 When cold-finished tubes as ordered require wall thicknesses ⁄4 in. [19.1 mm] or over, or an inside diameter 60 % or less of
the outside diameter, the permissible variations in wall thickness for hot-finished tubes shall apply.
10. Permissible Variations in Outside Diameter
10.1 Except as provided in 10.2, variations from the specified outside diameter shall not exceed the amounts prescribed in Table
3.
10.2 Thin-wall tubes usually develop significant ovality (out of roundness) during final annealing, or straightening, or both. The
diameter tolerances of Table 3 are not sufficient to provide for additional ovality expected in thin-wall tubes, and, for such tubes,
are applicable only to the mean of the extreme (maximum and minimum) outside diameter readings in any one cross section.
However, for thin wall tubes the difference in extreme outside diameter readings (ovality) in any one cross section shall not exceed
the following ovality allowances:
Outside Diameter Ovality Allowance
1 in. [25.4 mm] and under 0.020 in. [0.5 mm]
Over 1 in. [25.4 mm] 2.0 % of specified outside diameter
11. Permissible Variations in Length
11.1 Variations from the specified length shall not exceed the amounts prescribed in Table 4.
A450/A450M − 23
A
TABLE 3 Permissible Variations in Outside Diameter
Outside Diameter, Permissible Variations, in. [mm]
in. [mm]
Over Under
Hot-Finished Seamless Tubes
1 1
4 [101.6] and under ⁄64 [0.4] ⁄32 [0.8]
1 1 3
Over 4 to 7 ⁄2 [101.6 to 190.5], incl ⁄64 [0.4] ⁄64 [1.2]
1 1 1
Over 7 ⁄2 to 9 [190.5 to 228.6], incl ⁄64 [0.4] ⁄16 [1.6]
Welded Tubes and Cold-Finished Seamless Tubes
Under 1 [25.4] 0.004 [0.1] 0.004 [0.1]
1 to 1 ⁄2 [25.4 to 38.1], incl 0.006 [0.15] 0.006 [0.15]
Over 1 ⁄2 to 2 [38.1 to 50.8], excl 0.008 [0.2] 0.008 [0.2]
2 to 2 ⁄2 [50.8 to 63.5], excl 0.010 [0.25] 0.010 [0.25]
2 ⁄2 to 3 [63.5 to 76.2], excl 0.012 [0.3] 0.012 [0.3]
3 to 4 [76.2 to 101.6], incl 0.015 [0.38] 0.015 [0.38]
Over 4 to 7 ⁄2 [101.6 to 190.5], incl 0.015 [0.38] 0.025 [0.64]
Over 7 ⁄2 to 9 [190.5 to 228.6], incl 0.015 [0.38] 0.045 [1.14]
A
Except as provided in 10.2, these permissible variations include out-of-
roundness. These permissible variations in outside diameter apply to hot-finished
seamless, welded and cold-finished seamless tubes before other fabricating
operations such as upsetting, swaging, expanding, bending, or polishing.
A
TABLE 4 Permissible Variations in Length
Method of Outside Cut Length,
Manufacture Diameter, in. [mm]
in. [mm]
Over Under
Seamless, hot-finished All sizes ⁄16 [5] 0 [0]
Seamless, cold- Under 2 [50.8] ⁄8 [3] 0 [0]
finished 2 [50.8] and over ⁄16 [5] 0 [0]
Welded Under 2 [50.8] ⁄8 [3] 0 [0]
2 [50.8] and over ⁄16 [5] 0 [0]
A
These permissible variations in length apply to tubes before bending. They apply
to cut lengths up to and including 24 ft [7.3 m]. For lengths greater than 24 ft [7.3
m], the above over-tolerances shall be increased by ⁄8 in. [3 mm] for each 10 ft [3
m] or fraction thereof over 24 ft or ⁄2 in. [13 mm], whichever is the lesser.
12. Permissible Variations in Height of Flash on Electric-Resistance-Welded Tubes
12.1 For tubes manufactured to this specification, the weld flash on the outside of the tube shall be mechanically removed by
cutting prior to any subsequent cold work or sizing.
12.2 For tubes over 2 in. [50.8 mm] in outside diameter, or over 0.135 in. [3.44 mm] in wall thickness, the flash on the inside of
the tubes shall be mechanically removed by cutting to a maximum height of 0.010 in. [0.25 mm] at any point on the tube.
12.3 For tubes 2 in. [50.8 mm] and under in outside diameter and 0.135 in. [3.4 mm] and under in wall thickness, the flash on
the inside of the tube shall be mechanically removed by cutting to a maximum height of 0.006 in. [0.15 mm] at any point on the
tube.
13. Straightness and Finish
13.1 Finished tubes shall be reasonably straight and have smooth ends free of burrs. They shall have a workmanlike finish. Surface
imperfections (see Note 1) may be removed by grinding, provided that a smooth curved surface is maintained, and the wall
thickness is not decreased to less than that permitted by this or the product specification. The outside diameter at the point of
grinding may be reduced by the amount so removed.
NOTE 1—An imperfection is any discontinuity or irregularity found in the tube.
14. Repair by Welding
14.1 Repair welding of base metal defects in tubing is permissible only with the approval of the purchaser and with the further
understanding that the tube shall be marked “WR” and the composition of the deposited filler metal shall be suitable for the
composition being welded. Defects shall be thoroughly chipped or ground out before welding and each repaired length shall be
A450/A450M − 23
reheat treated or stress relieved as required by the applicable specification. Each length of repaired tube shall be tested
hydrostatically as required by the product specification.
14.2 Repair welding shall be performed using procedures and welders or welding operators that have been qualified in accordance
with ASME Boiler and Pressure Vessel Code, Section IX.
15. Retests
15.1 If the results of the mechanical tests of any group or lot do not conform to the requirements specified in the individual
specification, retests may be made on additional tubes of double the original number from the same group or lot, each of which
shall conform to the requirements specified.
16. Retreatment
16.1 If the individual tubes or the tubes selected to represent any group or lot fail to conform to the test requirements, the
individual tubes or the group or lot represented may be retreated and resubmitted for test. Not more than two reheat treatments
shall be permitted.
17. Test Specimens
17.1 Test specimens shall be taken from the ends of finished tubes prior to upsetting, swaging, expanding, or other forming
operations, or being cut to length. They shall be smooth on the ends and free of burrs and flaws.
17.2 If any test specimen shows flaws or defective machining, it may be discarded and another specimen substituted.
18. Method of Mechanical Testing
18.1 The specimens and mechanical tests required shall be made in accordance with Annex A2 of Test Methods and Definitions
A370 if inch-pound units are specified or to the requirements described in the applicable track of Test Methods A1058 if SI units
are specified.
18.2 Specimens shall be tested at room temperature.
18.3 Small or subsize specimens as described in Test Methods and Definitions A370 or Test Methods A1058 may be used only
when there is insufficient material to prepare one of the standard specimens. When using small or subsize specimens, the largest
one possible shall be used.
19. Flattening Test
19.1 A section of tube not less than 2 ⁄2 in. [63 mm] in length for seamless and not less than 4 in. [100 mm] in length for welded
shall be flattened cold between parallel plates in two steps. For welded tubes, the weld shall be placed 90° from the direction of
the applied force (at a point of maximum bending). During the first step, which is a test for ductility, no cracks or breaks, except
as provided for in 19.4, on the inside, outside, or end surfaces shall occur in seamless tubes, or on the inside or outside surfaces
of welded tubes, until the distance between the plates is less than the value of H calculated by the following equation:
11e t
~ !
H 5 (2)
e1t/D
where:
H = distance between flattening plates, in. [mm],
t = specified wall thickness of the tube, in. [mm],
D = specified outside diameter of the tube, in. [mm], and
e = deformation per unit length (constant for a given grade of steel: 0.07 for medium-carbon steel (maximum specified carbon
0.19 % or greater), 0.08 for low alloy steel, and 0.09 for low-carbon steel (maximum specified carbon 0.18 % or less)).
During the second step, which is a test for soundness, the flattening shall be continued until the specimen breaks or the opposite
walls of the tube meet. Evidence of laminated or unsound material, or of incomplete weld that is revealed during the entire
flattening test shall be cause for rejection.
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19.2 Surface imperfections in the test specimens before flattening, but revealed during the first step of the flattening test, shall be
judged in accordance with the finish requirements.
19.3 Superficial ruptures resulting from surface imperfections shall not be cause for rejection.
19.4 When low D-to-t ratio tubular products are tested, because the strain imposed due to geometry is unreasonably high on the
inside surface at the six and twelve o’clock locations, cracks at these locations shall not be cause for rejection if the D to t ratio
is less than 10.
20. Reverse Flattening Test
20.1 A 5 in. [100 mm] in length of finished welded tubing in sizes down to and including ⁄2 in. [12.7 mm] in outside diameter
shall be split longitudinally 90° on each side of the weld and the sample opened and flattened with the weld at the point of
maximum bend. There shall be no evidence of cracks or lack of penetration or overlaps resulting from flash removal in the weld.
21. Flaring Test
21.1 A section of tube approximately 4 in. [100 mm] in length shall stand being flared with a tool having a 60° included angle
until the tube at the mouth of the flare has been expanded to the percentages specified in Table 5 without cracking or showing
imperfections rejectable under the provisions of the product specification.
22. Flange Test
22.1 A section of tube shall be capable of having a flange turned over at a right angle to the body of the tube without cracking
or showing imperfections rejectable under the provisions of the product specification. The width of the flange for carbon and alloy
steels shall be not less than the percentages specified in Table 6.
23. Hardness Test
23.1 For tubes 0.200 in. [5.1 mm] and over in wall thickness, either the Brinell or Rockwell hardness test shall be used. When
Brinell hardness testing is used, a 10-mm ball with 3000, 1500, or 500-kg load, or a 5-mm ball with 750-kg load may be used,
at the option of the manufacturer.
23.2 For tubes less than 0.200 in. [5.1 mm] to and including 0.065 in. [1.7 mm] in wall thickness, the Rockwell hardness test shall
be used.
23.3 For tubes less than 0.065 in. [1.7 mm] in wall thickness, the hardness test shall not be required.
23.4 The Brinell hardness test may be made on the outside of the tube near the end, on the outside of a specimen cut from the
tube, or on the wall cross section of a specimen cut from the tube at the option of the manufacturer. This test shall be made so
that the distance from the center of the impression to the edge of the specimen is at least 2.5 times the diameter of the impression.
TABLE 5 Flaring Test Requirements
Minimum Expansion of Inside
Ratio of Inside
Diameter, %
Diameter to Outside
A Carbon Steels Low
Diameter
Alloy Steels
0.9 21 15
0.8 22 17
0.7 25 19
0.6 30 23
0.5 39 28
0.4 51 38
0.3 68 50
A
In determining the ratio of inside diameter to specified outside diameter, the
inside diameter shall be defined as the actual mean inside diameter of the material
tested.
A450/A450M − 23
TABLE 6 Flange Requirements
Outside Diameter of Tube, in. [mm] Width of Flange
To 2 ⁄2 [63.5], incl 15 % of OD
1 3 1
Over 2 ⁄2 to 3 ⁄4 [63.5 to 95.2], incl 12 ⁄2 % of OD
Over 3 ⁄4 to 8 [95.2 to 203.2], incl 10 % of OD
23.5 The Rockwell hardness test may be made on the inside surface, on the wall cross section, or on a flat on the outside surface
at the option of the manufacturer.
23.6 For tubes furnished with upset, swaged, or otherwise formed ends, the hardness test shall be made as prescribed in 23.1 and
23.2 on the outside of the tube near the end after the forming operation and heat treatment.
23.7 For welded or brazed tubes, the hardness test shall be made away from the joints.
23.8 When the product specification provides for Vickers hardness, such testing shall be in accordance with Test Method E92.
24. Hydrostatic Test
24.1 Except as provided in 24.2 and 24.3, each tube shall be tested by the manufacturer to a minimum hydrostatic test pressure
determined by the following equation:
Inch 2 Pound Units:P 5 32000 t/D (3)
SI Units:P 5 220.6t/D
where:
P = hydrostatic test pressure, psi or MPa,
t = specified wall thickness, in. or mm, and
D = specified outside diameter, in. or mm.
24.1.1 The hydrostatic test pressure determined by Eq 3 shall be rounded to the nearest 50 psi [0.5 MPa] for pressure below 1000
psi [7 MPa], and to the nearest 100 psi [1 MPa]
...