ASTM A 312/A 312M – 95a: Seamless and Welded Austenitic Stainless Steel Pipes
ASTM A 312/A 312M – 95a
Seamless and Welded Austenitic Stainless Steel Pipes
This specification covers austenitic steel pipe intended for high temperature and general corrosive service. H grades in the chemical composition table are specifically for high temperature service
Dimensions and Tolerances
-
Dimensions. All standard pipe sizes and wall thicknesses may be specified, subject to manufacturing limitations. Minimum wall thickness pipe is also covered as a supplementary requirement.
-
Tolerances. ASTM pipe
Manufacture
-
Materials. Refer to chemical composition table.
-
Manufacture. In order to comply with this specification the pipe must be manufactured by an automatic welding process using no filler metal, or it must be a seamless pipe. If a welded pipe has a nominal pipe size greater than 14 then it may be constructed from two longitudinal sections, and hence have two longitudinal welds. The pipe may be either hot finished or cold finished.
-
Heat treatment. Refer to heat treatment table and supplementary requirement S6.
-
Marking on each length of pipe: Manufacturer’s make or brand, specification number, ‘WR’ if weld repaired, ‘NPS’ and schedule, ‘NH’ if no hydrotesting performed, ‘ET’ if eddy-current tested, ‘UT’ if ultrasonic tested. (NPS = Nominal Pipe Size.)
Finish and Repair
-
Finish. The surface of the pipe must be clean and free of scale and contaminating iron particles. It can be bright annealed but may be pickled, blasted or can be passivated.
-
Repair by welding. Permitted on <20% of the weld seam length of welded pipe if >NPS 6 and having a wall thickness >0.200 in (mm). Tungsten-arc welding process is used for repairs, with filler metal to a grade as specified in A 312 (not repeated here). Weld repairs must be identified on the pipe and in test certificate.
Mandatory Testing
-
Transverse or Longitudinal Tension Test. One test made on a specimen for lots of less than 100 pipes. Two tests made for greater lots.
-
Flattening Test. 5% of pipe will be treated and at least 2 pipes from heat treated lot. For welded pipe, transverse guided face bend test may be conducted in place of flattening test.
-
Grain Size Examination. The following grades will be subjected to grain size determinations, with 5% of the pipe being examined: TP309H, TP309HCb, TP310H, TP310HCb – grain size No 6 or coarser, UNS S32615 – grain size No 3 or finer.
-
Hydrostatic Test. Each pipe will be tested unless the pipe exceeds NPS 10 and the purchaser has agreed, or has agreed to alternative Nondestructive testing.
-
Nondestructive Examination. All processing must be completed before testing. Either Ultrasonic (Practice E 213) or Eddy Current (Practice E 426) testing may be used, or both. The operator must be qualified. A reference standard must be employed to regularly calibrate the testing equipment. Guidance regarding the reference standards, detailed in A 312, is not included in this summary.
Ordering Information
Item
Notes
Specification number
ASTM A 312/A 312M-95a
Size
Nominal pipe size or outside diameter. Schedule or average wall thickness.
Quantity
Random or specified lengths. Total length or number of lengths.
Name of material
Austenitic stainless steel pipe
Process
Seamless or welded
Grade
Selected from chemical composition table
End finish
Plain ends with all burrs removed is ASTM requirement. Bevelled, or other end finishes can be specified.
Test report
DIN 50049.3.1.B standard, or DIN 50049.3.1.C optional (3rd party witness test) at extra cost
Options and supplementary requirements
Refer to optional and supplementary requirements S1 to S8
Note -The above table is based on ASTM requirements except with regard to alternative end finishes and test reports, where standard practice options are added. See also page 10-2 for ISO based ordering and general delivery information.
Optional and Supplementary Requirements
-
Chemical analysis of one billet or one length of flat rolled stock from each heat may be performed if required by purchaser.
-
Hydrostatic, eddy-current or ultrasonic testing.
-
Discontinuities. The type, size, location, orientation, of discontinuities that are of interest during NDT may be specified.
-
Hot or cold finishing.
-
Passivating treatment may be requested.
-
Surface Finish. Bright annealed or other surface finish.
-
Pipe Marking. The weight may be requested for pipe >NPS4.
-
S1 Product Analysis. NPS 5 and larger one analysis for each ten lengths from each heat of
-
steel. NPS smaller than 5 then only 10% need be tested.
-
S1 Tranverse Tension Tests. NPS 8 and larger can have one transverse tension test on 10% of lengths per he at of steel.
-
S1 Flattening Test. A flattening test will be made on a specimen from one or both ends of each pipe. The number of tests per pipe needs to be specified.
-
S1 Etching Tests. Etching tests show the homogeneity of pipes and are made on a cross section from one or both ends of a pipe.
-
S1 Radiographic Examination. The entire length of weld will be examined for any double welded pipe. In addition the pipe will be marked RT and the test results included in the certification.
-
S1 Stabilising Heat Treatment. The solution annealed grades TP309HCb, TP310HCb, TP321, TP321H, TP347, TP347H, TP348 and TP348H will be given a stabilisation heat treatment. Temperature will be as agreed between purchaser and vendor.
-
S1 Intergranular Corrosion Test. This test in accordance with Practices A 262 Practice E.
-
S1 Minimum Wall Pipe. A minimum wall thickness may be specified, in which case the wall thickness may not be below the thickness
Tensile Requirements
Tensile Strength min |
Yield Strength min |
Elongation in 2 in (50 mm) or 4D min |
|||||
Grade |
UNS |
||||||
ksi |
MPa |
ksi |
MPa |
Longit % |
Trans % |
||
All |
All |
75 |
515 |
30 |
205 |
35 |
25 |
TP304L |
S30403 |
70 |
485 |
25 |
170 |
35 |
25 |
TP304N |
S30451 |
80 |
550 |
35 |
240 |
35 |
25 |
S31272 |
65 |
450 |
29 |
200 |
35 |
25 |
|
TP316L |
S31603 |
70 |
485 |
25 |
170 |
35 |
25 |
TP316N |
S31651 |
80 |
550 |
35 |
240 |
35 |
25 |
TP321 |
S32100 |
75(701) |
515(4851) |
30(251) |
205(1701) |
35 |
25 |
TP321H |
S32109 |
75(701) |
515(4851) |
30(251) |
205(1701) |
35 |
25 |
TPXM- 10 |
S21900 |
90 |
620 |
50 |
345 |
35 |
25 |
TPXM- 11 |
S21904 |
90 |
620 |
50 |
345 |
35 |
25 |
TPXM- 19 |
S20910 |
100 |
690 |
55 |
380 |
35 |
25 |
TPXM- 29 |
S24000 |
100 |
690 |
55 |
380 |
35 |
25 |
S31254 |
94 |
650 |
44 |
300 |
35 |
25 |
|
S30615 |
90 |
620 |
40 |
275 |
35 |
25 |
|
S30815 |
87 |
600 |
45 |
310 |
35 |
25 |
|
S31050 |
84(782) |
580(5402) |
39(372) |
270(2552) |
25 |
– |
|
S30600 |
78 |
540 |
35 |
240 |
35 |
25 |
|
S31726 |
80 |
550 |
35 |
240 |
35 |
25 |
|
S32615 |
80 |
550 |
32 |
220 |
25 |
– |
|
S33228 |
73 |
500 |
27 |
185 |
35 |
25 |
|
S24565 |
115 |
795 |
60 |
415 |
35 |
25 |
|
S30415 |
87 |
600 |
42 |
290 |
35 |
25 |
|
S32654 |
109 |
750 |
62 |
430 |
35 |
25 |
|
S35315 |
94 |
650 |
39 |
270 |
35 |
25 |
|
N08367 |
100(953) |
690(6553) |
45(453) |
310(3103) |
30 |
– |
|
N08904 |
71 |
490 |
31 |
215 |
35 |
25 |
Notes
– All = All grades listed in the chemical composition table other than those itemised in this table. 1 Values for wall thickness >3/8 in (9.5 mm)
-
Values for wall thickness >1/4 in (6.35 mm)
-
Values for wall thickness >0.187 in (4.75 mm)
Heat Treatment
Grade |
UNS |
Temperature °F |
Temperature °C |
Treatment |
All |
All |
1900 |
1040 |
Minimum solution temperature. Quench1 |
TP304H |
S30409 |
1900(1900) |
1040(1040) |
Minimum solution temp for cold (hot) working. Quench1 |
TP316H |
S31609 |
1900(1900) |
1040(1040) |
Minimum solution temp for cold (hot) working. Quench1 |
TP321H |
S32109 |
2000(1925) |
1090(1050) |
Minimum solution temp for cold (hot) working. Quench1 |
TP347H |
S34709 |
2000(1925) |
1090(1050) |
Minimum solution temp for cold (hot) working. Quench1 |
TP348H |
S34809 |
2000(1925) |
1090(1050) |
Minimum solution temp for cold (hot) working. Quench1 |
S30815 |
1920 |
1050 |
Minimum solution temperature. Quench 1,2 |
|
S31272 |
1920 |
1050 |
Minimum solution temperature. Quench 1 |
|
S31254 |
2100 |
1150 |
Minimum solution temperature. Quench1 |
|
S24565 |
2050-2140 |
1121-1170 |
Solution temperature range. Quench1 |
|
S32654 |
2100 |
1150 |
Minimum solution temperature. Quench1 |
|
S35315 |
2010 |
1100 |
Minimum solution temperature. Quench1 |
|
N08367 |
2025 |
1100 |
Minimum solution temperature. Quench1 |
|
N08904 |
2000 |
1100 |
Minimum solution temperature. Quench1 |
Notes
-
All = All grades listed in the chemical composition table other than those itemised in this table. 1 Quench in water or rapid cool by other means
2 Pipe marking to include heat number and heat-treatment lot number
Chemical Composition
Grade
UNS
Composition Percentage, max or range
&DUERn
C
0DQJDQHVe
Mn
3KRVSKRUXs
P
6XOSKXr
S
6LOLFRn
Si
1LFNHl Ni
&KURPLXmCr
0RO\EGHQXm
Mo
Note
TP304
S30400
0.08
2.00
0.040
0.030
0.75
8.00-11.0
18.0-20.0
–
TP304H
S30409
0.04-
0.10
2.00
0.040
0.030
0.75
8.00-11.0
18.0-20.0
–
TP304L
S30403
0.035
2.00
0.040
0.030
0.75
8.00-13.0
18.0-20.0
–
25
TP304N
S30451
0.08
2.00
0.040
0.030
0.75
8.00-11.0
18.0-20.0
–
1
TP304LN
S30453
0.035
2.00
0.040
0.030
0.75
8.00-11.0
18.0-20.0
–
1
TP309Cb
S30940
0.08
2.00
0.045
0.030
0.75
12.0-16.0
22.0-24.0
0.75
2
TP309H
S30909
0.04-
0.10
2.00
0.040
0.030
0.75
12.0-15.0
22.0-24.0
–
TP309HCb
S30941
0.04-
0.10
2.00
0.045
0.030
0.75
12.0-16.0
22.0-24.0
0.75
2
TP309S
S30908
0.08
2.00
0.045
0.030
0.75
12.0-15.0
22.0-24.0
0.75
TP310Cb
S31040
0.08
2.00
0.045
0.030
0.75
19.0-22.0
24.0-26.0
0.75
2
TP310H
S31009
0.04-
0.10
2.00
0.040
0.030
0.75
19.0-22.0
24.0-26.0
–
TP310HCb
S31041
0.04-
0.10
2.00
0.045
0.030
0.75
19.0-22.0
24.0-26.0
0.75
2
TP310S
S31008
0.080
2.00
0.045
0.030
0.75
19.0-22.0
24.0-26.0
0.75
S31272
0.08-
0.12
1.5-2.0
0.030
0.015
0.3-0.7
14.0-16.0
14.0-16.0
1.0-1.4
3
TP316
S31600
0.08
2.00
0.040
0.030
0.75
11.0-14.0
16.0-18.0
2.00-3.00
24
TP316H
S31609
0.04-
0.10
2.00
0.040
0.030
0.75
11.0-14.0
16.0-18.0
2.00-3.00
24
TP316L
S31603
0.035
2.00
0.040
0.030
0.75
10.0-15.0
16.0-18.0
2.00-3.00
25
TP316N
S31651
0.08
2.00
0.040
0.030
0.75
11.0-14.0
16.0-18.0
2.00-3.00
1,24
TP316LN
S31653
0.035
2.00
0.040
0.030
0.75
11.0-14.0
16.0-18.0
2.00-3.00
1,24
TP317
S31700
0.08
2.00
0.040
0.030
0.75
11.0-14.0
18.0-20.0
3.00-4.00
TP317L
S31703
0.035
2.00
0.040
0.030
0.75
11.0-15.0
18.0-20.0
3.00-4.00
TP321
S32100
0.08
2.00
0.040
0.030
0.75
9.00-13.0
17.0-20.0
–
20
TP321H
S32109
0.04-
0.10
2.00
0.040
0.030
0.75
9.00-13.0
17.0-20.0
–
21
TP347
S34700
0.08
2.00
0.040
0.030
0.75
9.00-13.0
17.0-20.0
–
22
TP347H
S34709
0.04-
0.10
2.00
0.040
0.030
0.75
9.00-13.0
17.0-20.0
–
23
TP348
S34800
0.08
2.00
0.040
0.030
0.75
9.00-13.0
17.0-20.0
–
4, 22
TP348H
S34809
0.04-
0.10
2.00
0.040
0.030
0.75
9.00-13.0
17.0-20.0
–
4, 23
TPXM-10
S21900
0.08
8.0-10.0
0.040
0.030
1.00
5.50-7.50
19.0-21.5
–
5
TPXM-11
S21904
0.04
8.0-10.0
0.040
0.030
1.00
5.50-7.50
19.0-21.5
–
5
TPXM-15
S38100
0.08
2.00
0.030
0.030
1.50-
2.50
17.5-18.5
17.0-19.0
–
TPXM-19
S20910
0.060
4.0-6.0
0.040
0.030
1.00
11.5-13.5
20.5-23.5
1.50-3.00
6
TPXM-29
S24000
0.080
11.5-14.5
0.060
0.030
1.00
2.25-3.75
17.0-19.0
–
7
S31254
0.020
1.00
0.030
0.010
0.80
17.5-18.5
19.5-20.5
6.00-6.50
8
S30615
0.16-
0.24
2.00
0.030
0.030
3.2-4.0
13.5-16.0
17.0-19.5
–
9
S30815
0.05-
0.10
0.80
0.040
0.030
1.40-
2.00
10.0-12.0
20.0-22.0
–
10
S31050
0.025
2.00
0.020
0.015
0.4
20.5-23.5
24.0-26.0
1.6-2.6
11
S30600
0.018
2.00
0.020
0.020
3.7-4.3
14.0-15.5
17.0-18.5
0.20
12
S31725
0.03
2.00
0.040
0.030
0.75
13.5-17.5
18.0-20.0
4.0-5.0
13,26
S31726
0.03
2.00
0.040
0.030
0.75
13.5-17.5
17.0-20.0
4.0-5.0
14,26
S32615
0.07
2.00
0.045
0.030
4.8-6.0
19.0-22.0
16.5-19.5
0.3-1.5
15
S33228
0.04-
0.08
1.00
0.020
0.015
0.30
31.0-33.0
26.0-28.0
–
16
S24565
0.03
5.0-7.0
0.030
0.010
1.00
16.0-18.0
23.0-25.0
4.0-5.0
17
S30415
0.04-
0.06
0.80
0.045
0.030
1.00-
2.00
9.0-10.0
18.0-19.0
–
18
S32654
0.020
2.00-4.00
0.030
0.005
0.50
21.0-23.0
24.0-25.0
7.0-8.0
19
TP347LN
S34751
0.005-
0.020
2.00
0.040
0.030
0.75
9.00-13.0
17.0-20.0
–
27
S35315
0.04-
0.08
2.00
0045
0.030
0.75
34.0-36.0
24.0-26.0
–
18
N08367
0.030
2.00
0.040
0.030
1.00
23.50-
25.50
20.0-22.0
6.00-7.00
28
N08904
0.020
2.00
0.045
0.035
1.00
23.0-28.0
19.0-23.0
4.0-5.0
29
Composition Notes
1 Nitrogen 0.10-0.16%
2 Niobium + Tantalum: 10 x Carbon min, 1.10% max 3 Titanium 0.3-0.6%, Boron 0.004-0.008%
4 Tantalum 0.10% max
5 Nitrogen 0.15-0.40%
6 Niobium + Tantalum: 0.10-0.30%, Nitrogen 0.20-0.40%, Vanadium 0.10-0.30%
7 Nitrogen 0.20-0.40%
8 Nitrogen 0.18-0.22%, Copper 0.50-1.00%
9 Aluminium 0.8-1.5%
10 Nitrogen 0.14-0.20%, Cerium 0.03-0.08%
11 Nitrogen 0.09-0.15%
-
Copper 0.50% max
-
Nitrogen 0.10% max, Copper 0.75% max
-
Nitrogen 0.10-0.20%, Copper 0.75% max
15 Copper 1.5-2.5%
-
Niobium + Tantalum: 0.6-1.0%, Cerium 0.05-0.10%, Aluminium 0.025% max
-
Niobium + Tantalum: 0.1% max, Nitrogen 0.4-0.6%
18 Nitrogen 0.12-0.18%, Cerium 0.03-0.08%
19 Nitrogen 0.45-0.55%, Copper 0.30-0.60%
-
Titanium >5 x Carbon and 0.70% max
-
Titanium >4 x Carbon and 0.6% max
-
Niobium + Tantalum >10 x Carbon and 1.00% max 23 Niobium + Tantalum >8 x Carbon and 1.0% max
-
For welded pipe the nickel range is 10.0-14.0% max
-
Carbon 0.040% max is necessary for pipes where many drawing passes are required, as with outside diameter <0.5 in (12.7 mm) or nominal wall thickness <0.049 in (1.2 mm) (minimum wall thickness <0.044 in (1.12 mm))
-
For welded pipe, Phosphorus 0.045% max
-
Niobium + Tantalum: 0.2-0.5%, >15 x Carbon, Nitrogen 0.06-0.10%
-
Nitrogen 0.18-0.25%, Copper 0.75% max
-
Nitrogen 0.10% max, Copper 1.0-2.0% Note
-
-
Niobium is sometimes referred to as Columbium