|A249/ A249M||A269||A270||A778||A335/ A335M||A691|
|A790||A312||A409||A554||A358/ A358M||A928/ A928M|
CS pipe Grades
Standard Specification for
Seamless and Welded Austenitic Stainless Steel Tubing for
This standard is issued under the fixed designation A 269; 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 (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1.1 This specification covers grades of nominal-wallthickness,
stainless steel tubing for general corrosion-resisting
and low- or high-temperature service, as designated in Table 1.
1.2 The tubing sizes and thicknesses usually furnished to
this specification are 1⁄4 in. (6.4 mm) in inside diameter and
larger and 0.020 in. (0.51 mm) in nominal wall-thickness and
1.3 Mechanical property requirements do not apply to
tubing smaller than 1⁄8 in. (3.2 mm) in inside diameter or 0.015
in. (0.38 mm) in thickness.
NOTE 1—Additional testing requirements may apply for use in ASME
1.4 Optional supplementary requirements are provided and,
when one or more of these are desired, each shall be so stated
in the order.
1.5 The values stated in inch-pound units are to be regarded
as the standard.
2. Referenced Documents
2.1 ASTM Standards: 2
A 262 Practices for Detecting Susceptibility to Intergranular
Attack in Austenitic Stainless Steels
A 370 Test Methods and Definitions for Mechanical Testing
of Steel Products
A 480/A 480M Specification for General Requirements for
Flat-Rolled Stainless and Heat-Resisting Steel Plate,
Sheet, and Strip
A 632 Specification for Seamless and Welded Austenitic
Stainless Steel Tubing (Small-Diameter) for General Service
A 1016/A 1016M Specification for General Requirements
for Ferritic Alloy Steel, Austenitic Alloy Steel, and Stainless
E 527 Practice for Numbering Metals and Alloys (UNS)
2.2 ASME Piping Code:
ASME B31.3 Process Piping3
2.3 Other Standard:
SAE J1086 Practice for Numbering Metals and Alloys
3. Ordering Information
3.1 Orders for material under this specification should
include the following, as required, to describe the desired
3.1.1 Quantity (feet, metres, or number of lengths),
3.1.2 Name of material (seamless or welded tubes),
3.1.3 Grade (Table 1),
3.1.4 Size (outside diameter and nominal wall thickness),
3.1.5 Length (specific or random),
3.1.6 Optional requirements (heat treatment, see Section 6;
hydrostatic or nondestructive electric test, see Section 10),
3.1.7 Test report required (see Section on Inspection of
Specification A 1016/A 1016M),
3.1.8 Specification designation, and
3.1.9 Special requirements and any supplementary requirements
4. General Requirements
4.1 Material furnished under this specification shall conform
to the applicable requirements of the current edition of
Specification A 1016/A 1016M, unless otherwise provided
5.1 The tubes shall be made by the seamless or welded
5.2 At the manufacturer’s option, tubing may be furnished
either hot finished or cold finished.
6. Heat Treatment
6.1 All material shall be furnished in the heat-treated
condition. Except as provided in 6.2, the heat-treatment procedure
shall, except for S31254 and S32654 (see 6.3), S24565
(see 6.4), N08367 (see 6.8), N08904 (see 6.5) and N08926 (see
6.7), consist of heating the material to a minimum temperature
of 1900 °F (1040 °C) and quenching in water or rapidly
cooling by other means. Alternatively, for seamless tubes,
immediately following hot forming while the temperature of
the tubes is not less than the specified minimum solution
treatment temperature, tubes may be individually quenched in
water or rapidly cooled by other means.
6.2 Controlled structural or special service characteristics
shall be specified as a guide for the most suitable heat
treatment. If the final heat treatment is at a temperature under
1900 °F and is so specified on the order, each tube shall be
stenciled with the final heat treatment temperature in degrees
Fahrenheit after the suffix “HT”.
6.3 S31254 and S32654 shall be heat-treated to a minimum
temperature of 2100 °F (1150 °C) followed by quenching in
water or rapidly cooling by other means.
6.4 S24565 shall be heat-treated in the range 2050 °F (1120
°C) to 2140 °F (1170 °C) followed by quenching in water or
rapidly cooling by other means.
6.5 N08904 shall be heat treated to a minimum temperature
of 2000 °F (1100 °C) followed by quenching in water or
rapidly cooling by other means.
6.6 A solution annealing temperature above 1950 °F (1065
°C) may impair the resistance to intergranular corrosion after
subsequent exposure to sensitizing conditions in TP321,
TP347, and TP348. When specified by the purchaser, a lower
temperature stabilization or re-solution anneal shall be used
subsequent to the initial high temperature solution anneal (see
Supplementary Requirement S3).
6.7 N08926 shall be heat-treated to a minimum temperature
of 2010 °F (1100 °C) followed by quenching in water or
rapidly cooling by other means.
6.8 UNS N08367 should be solution annealed from 2025 °F
(1107 °C) minimum followed by rapid quenching.
6.9 Solution annealing of S35045 shall consist of heating
the material to a temperature of 2000 °F (1093 °C) minimum
for an appropriate time, followed by cooling in still air or at a
6.10 S31727 and S32053 shall be solution annealed in the
range 1975 to 2155 °F (1080 to 1180 °C) followed by
quenching in water or rapidly cooling by other means.
7. Chemical Composition
7.1 The steel shall conform to the requirements as to
chemical composition as prescribed in Table 1.
8. Product Analysis
8.1 An analysis of either one billet or one length of
flat-rolled stock or one tube shall be made from each heat. The
chemical composition thus determined shall conform to the
8.2 A product analysis tolerance of Table number A1.1 in
Specification A 480/A 480M shall apply. The product analysis
tolerance is not applicable to the carbon content for material
with a specified maximum carbon of .04 % or less.
8.3 If the original test for product analysis fails, retests of
two additional billets, lengths of flat-rolled stock, or tubes shall
be made. Both retests for the elements in question shall meet
the requirements of the specification; otherwise all remaining
material in the heat or lot shall be rejected or, at the option of
the producer, each billet, length of flat-rolled stock, or tube
may be individually tested for acceptance. Billets, lengths of
flat-rolled stock, or tubes which do not meet the requirements
of the specification shall be rejected.
9. Mechanical Tests Required
9.1 Flaring Test (Seamless Tubes)— One test shall be made
on specimens from one end of one tube from each lot (Note 2)
of finished tubes.
NOTE 2—The term lot applies to all tubes prior to cutting to length of
the same nominal size and wall thickness which are produced from the
same heat of steel. When final heat treatment is in a batch-type furnace, a
heat-treatment lot shall include only those tubes of the same size and from
the same heat which are heat treated in the same furnace charge. When the
final heat treatment is in a continuous furnace or when the heat-treated
condition is obtained directly by quenching after hot forming, the number
of tubes of the same size and from the same heat in a heat-treatment lot
shall be determined from the size of the tubes as prescribed in Table 2.
9.2 Flange Test (Welded Tubes)—One test shall be made on
specimens from one end of one tube from each lot (Note 2) of
9.3 Hardness Test—Brinell or Rockwell hardness determination
shall be made on specimens from two tubes from each
lot. The term lot applies to all tubes prior to cutting, of the same
nominal diameter and wall thickness that are produced from
the same heat of steel. When final heat treatment is in a
batch-type furnace, a lot shall include only those tubes of the
same size and the same heat which are heat treated in the same
furnace charge. When the final heat treatment is in a continuous
furnace or when the heat-treated condition is obtained directly
by quenching after hot forming, a lot shall include all tubes of
the same size and heat, heat treated in the same furnace at the
same temperature, time at heat, and furnace speed, or all tubes
of the same size and heat, hot formed and quenched in the same
9.4 When more than one heat is involved, the flaring,
flanging, and hardness test requirements shall apply to each
9.5 Reverse Flattening Test—For welded tubes, one reverse
flattening test shall be made on a specimen from each 1500 ft
(460 m) of finished tubing. Coiled tubing greater than 1500 ft
(450 m) in length shall be sampled at both ends. A coil must be
continuous without any circumferential butt welds.
10. Hydrostatic or Nondestructive Electric Test
10.1 Each tube shall be subjected to the nondestructive
electric test or the hydrostatic test. The type of test to be used
shall be at the option of the manufacturer, unless otherwise
specified in the purchase order.
11. Hardness Requirements
11.1 Grades TPXM-29, S24565, N08367, and N08926
tubes shall have a hardness number not exceeding 256 HB/270
HV or 100 HRB. Grades TPXM-10, TPXM-11, and TPXM-19
tubes shall have a hardness number not exceeding 269 HB/285
HV or 25 HRC. S31254 shall have a hardness number not
exceeding 220 HB/230 HV or 96 HRB. S32654 shall have a
hardness number not exceeding 250 HB/263 HV or 100 HRB.
Tubes made from all other grades shall have a hardness number
not exceeding 192 HB/200 HV or 90 HRB.
11.2 For tubing less than 0.065 in. (1.65 mm) in wall
thickness, it is permissible to use the Rockwell superficial
hardness test or the Vickers hardness test. When the Vickers
test is used, the values of 11.1 will apply. The superficial
hardness number for Grade TPXM-29 tubes shall not exceed
80 on the 30 T scale or 92 on the 15 T scale. The hardness
number for Grades TPXM-10, TPXM-11, and TPXM-19 tubes
shall not exceed 46 on the 30 N scale or 73 on the 15 N scale.
The hardness number for S31254 shall not exceed 79 on the 30
T scale or 91 on the 15 T scale. Tubes made from all other
grades shall not exceed 74 on the 30 T scale or 88 on the 15 T
11.3 The hardness test shall not be required on tubes smaller
than 1⁄4 in. (6.4 mm) in inside diameter or tubes having a wall
thickness thinner than 0.020 in. (0.51 mm) (see A2.4 of
Methods and Definitions A 370). Smaller or thinner tubes
should be tension tested only, in accordance with Specification
12. Permissible Variations in Dimensions
12.1 Variations in outside diameter, wall thickness, and
length, from those specified, shall not exceed the amounts
prescribed in Table 3.
12.2 The permissible variations in outside diameter given in
Table 3 are not sufficient to provide for ovality in thin-walled
tubes, as defined in the Table. In such tubes, the maximum and
minimum diameters at any cross section shall deviate from the
nominal diameter by no more than twice the permissible
variation in outside diameter given in Table 3; however, the
mean diameter at that cross section must still be within the
given permissible variation.
13. Surface Condition
13.1 The tubes shall be pickled free of scale. When bright
annealing is used, pickling is not necessary.
14. Product Marking
14.1 In addition to the marking prescribed in Specification
A 1016/A 1016M, the marking shall include whether the tubing
is seamless or welded and the final heat-treatment temperature
in degrees Fahrenheit after the suffix “HT” if the final heat
treatment temperature is under 1900°F (1040°C).
14.2 When the Nondestructive Electric Test is performed,
each length of tubing shall be marked with the letters “NDE,”
and the certification, when required, shall also indicate this test.
15.1 austenitic stainless steel; seamless steel tube; stainless
steel tube; steel tube; welded steel tube
The following supplementary requirements shall apply only when specified by the purchaser in the
inquiry, contract, or order.
S1. Stress-Relieved Annealed Tubes
S1.1 For use in certain corrosives, particularly chlorides
where stress corrosion may occur, tubes in Grades TP304L,
TP316L, TP321, TP347, and TP348 may be specified in the
S1.2 When stress-relieved tubes are specified, tubes shall be
given a heat treatment at 1550 to 1650 °F (845 to 900 °C) after
roll straightening. Cooling from this temperature range may be
either in air or by slow cooling. No mechanical straightening is
permitted after the stress-relief treatment.
S1.3 Straightness of the tubes and additional details of this
supplementary requirement shall be agreed upon between the
manufacturer and purchaser.
S2. Air Underwater Pressure Test
S2.1 When specified, the tubing shall be examined by the air
underwater pressure test.
S3. Stabilizing Heat Treatment
S3.1 Subsequent to the solution anneal required in Section
6, Grades TP321, TP347, and TP348 shall be given a stabilization
heat treatment at a temperature lower than that used for
the initial solution annealing heat treatment. The temperature
of stabilization heat treatment shall be at a temperature as
agreed upon between the purchaser and vendor.
S4. Intergranular Corrosion Test
S4.1 When specified, material shall pass intergranular corrosion
tests conducted by the manufacturer in accordance with
Practices A 262, Practice E.
S4.2 A stabilization heat treatment in accordance with
Supplementary Requirement S3 may be necessary and is
permitted in order to meet this requirement for the grades
containing titanium or columbium.