STAINLESS STEEL PIPES ASTM A312


The scope of this article is to collect key information about stainless steel pipes ASTM A312: applications, dimensional range per ASME B36.19, chemical composition of the most common stainless steel grades (from TP304 upwards), mechanical properties (as yield/tensile strength and elongation) and, manufacturing tolerances for outside diameter and wall thickness.


 

STAINLESS STEEL PIPES ASTM A312

Stainless steel pipes ASTM A312

The ASTM A312/ASME SA312 specification sets standards for seamless and welded austenitic stainless light-weight steel pipes which are used at high temperature and/or for corrosive service. These pipes are used in the process, petrochemical, pharmaceutical and food industries. The most common grades are SS304 and SS316, but a variety of chrome, nickel and moly alloys are available originating a multitude of grades. Such grades can be grouped into four main categories:

  • austenitic stainless steels
  • ferritic stainless steels
  • martensitic stainless steels
  • duplex and super duplex stainless steels

The standard dimensions of stainless steel pipes are set by the ASME B36.19 specification.

The specification:

This guide covers standard specification for seamless, straight-seam welded, and cold worked welded austenitic stainless steel pipe intended for high-temperature and general corrosive service. Several grades of steel shall conform to the required chemical composition for carbon, manganese, phosphorus, sulfur, silicon, chromium, nickel, molybdenum, titanium, columbium, tantalum, nitrogen, vanadium, copper, cerium, boron, aluminum, and others. All pipes shall be furnished in the heat-treated condition in accordance with the required heat treating temperature and cooling/testing requirements. Tensile properties of the material shall conform to the prescribed tensile strength and yield strength. The steel pipe shall undergo mechanical tests such as transverse or longitudinal tension test and flattening test. Grain size determination and weld decay tests shall be performed. Each pipe shall also be subjected to the nondestructive electric test or the hydrostatic test. This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.

(Source: ASTM)


 

DIMENSIONS OF STAINLESS STEEL PIPES ASTM A312

The table shows the outside diameter and wall thickness chart for ASTM A312 stainless steel pipes in mm.

Note: schedule 5S is hard to find on the market, therefore schedule 10S is recommended for pipe specifications and piping classes.
NPS OD SCH 5S SCH 10S SCH 40S SCH 80S
1/4 13.72 1.65 2.24 3.02
3/8 17.15 1.65 2.31 3.2
1/2 21.34 1.65 2.11 2.77 3.73
3/4 26.67 1.65 2.11 2.87 3.91
1 33.4 1.65 2.77 3.38 4.55
1 1/4 42.16 1.65 2.77 3.56 4.85
1 1/2 48.26 1.65 2.77 3.68 5.08
2 60.33 1.65 2.77 3.91 5.54
2 1/2 73.03 2.11 3.05 5.16 7.01
3 88.9 2.11 3.05 5.49 7.62
3 1/2 101.6 2.11 3.05 5.74 8.08
4 114.3 2.11 3.05 6.02 8.56
5 141.3 2.77 3.4 6.55 9.53
6 168.28 2.77 3.4 7.11 10.97
8 219.08 2.77 3.76 8.18 12.7
10 273.05 3.4 4.19 9.27 12.7
12 323.85 3.96 4.57 9.53 12.7
14 355.6 3.96 4.78 9.53 12.7
16 406.4 4.19 4.78 9.53 12.7
18 457.2 4.19 4.78 9.53 12.7
20 508 4.78 5.54 9.53 12.7
22 558.8 4.78 5.54
24 609.6 5.54 6.35 9.53 12.7
26 660.4
28 711.2
30 762 6.35 7.92

 


CHEMICAL COMPOSITION OF STAINLESS STEEL PIPES ASTM A312

The table shows the chemical composition of the most common grades of stainless steel pipes under the ASTM A312 specification:

A312 SS PIPES
GRADES
UNS C Mn P S Si Cr Ni Mo Ti Nb N
TP304 S3040 0.08 2.0 0.045 0.030 1.0 18.0-20.0 8.0-11.0
TP304L S30403 0.035 2.0 0.045 0.030 1.0 18.0-20.0 8.0-13.0
TP304H S30409 0.04-0.10 2.0 0.045 0.030 1.0 18.0-20.0 8.0-11.0
TP304N S30451 0.08 2.0 0.045 0.030 1.0 18.0-20.0 8.0-18.0 0.10-0.16
TP304LN S30453 0.035 2.0 0.045 0.030 1.0 18.0-20.0 8.0-12.0 0.10-0.16
TP309S S30908 0.08 2.0 0.045 0.030 1.0 22.0-24.0 12.0-15.0 0.75
TP309H S30909 0.04-0.10 2.0 0.045 0.030 1.0 22.0-24.0 12.0-15.0
TP309Cb S30940 0.08 2.0 0.045 0.030 1.0 22.0-24.0 12.0-16.0 0.75 10xC min
1.10 max
TP309HCb S30941 0.04-0.10 2.0 0.045 0.030 1.0 22.0-24.0 12.0-16.0 0.75 10xC min
1.10 max
TP310S S3108 0.08 2.0 0.045 0.030 1.0 24.0-26.0 19.0-22.0 0.75
TP310H S3109 0.04-0.10 2.0 0.045 0.030 1.0 24.0-26.0 19.0-22.0
TP310Cb S31040 0.08 2.0 0.045 0.030 1.0 24.0-26.0 19.0-22.0 0.75 10xC min
1.10 max
TP310HCb S31041 0.04-0.10 2.0 0.045 0.030 1.0 24.0-26.0 19.0-22.0 0.75 10xC min
1.10 max
TP316 S3160 0.08 2.0 0.045 0.030 1.0 16.0-18.0 11.0-14.0 2.0-3.0
TP316L S31603 0.035 2.0 0.045 0.030 1.0 16.0-18.0 10.0-14.0 2.0-3.0
TP316H S31609 0.04-0.10 2.0 0.045 0.030 1.0 16.0-18.0 11.0-14.0 2.0-3.0
TP316Ti S31635 0.08 2.0 0.045 0.030 0.75 16.0-18.0 10.0-14.0 2.0-3.0 5x
(C-N)
-0.70
0.10
TP316N S31651 0.08 2.0 0.045 0.030 1.0 16.0-18.0 10.0-14.0 2.0-3.0 0.10-0.16
TP316LN S31653 0.035 2.0 0.045 0.030 1.0 16.0-18.0 11.0-14.0 2.0-3.0 0.10-0.16
TP317 S3170 0.08 2.0 0.045 0.030 1.0 18.0-20.0 10.0-14.0 3.0-4.0
TP317L S31703 0.035 2.0 0.045 0.030 1.0 18.0-20.0 11.0-15.0 3.0-4.0
TP321 S3210 0.08 2.0 0.045 0.030 1.0 17.0-19.0 9.0-12.0 0.10
TP321H S32109 0.04-0.10 2.0 0.045 0.030 1.0 17.0-19.0 9.0-12.0 0.10
TP347 S3470 0.08 2.0 0.045 0.030 1.0 17.0-19.0 9.0-13.0
TP347H S34709 0.04-0.10 2.0 0.045 0.030 1.0 17.0-19.0 9.0-13.0
TP347LN S34751 0.05-0.02 2.0 0.045 0.030 1.0 17.0-19.0 9.0-13.0 0.20-
50.0
0.06-0.10
TP348 S3480 0.08 2.0 0.045 0.030 1.0 17.0-19.0 9.0-13.0
TP348H S34809 0.04-0.10 2.0 0.045 0.030 1.0 17.0-19.0 9.0-13.0

 


 

MECHANICAL PROPERTIES OF STAINLESS STEEL PIPES A312

SS Pipes Grade Tensile Strength
N/mm2 (min)
Yield Strength
N/mm2 (min)
Elongation
% (min)
TP304 515 205 35
TP304L 485 170 35
TP316 515 205 35
TP316L 485 170 35
TP321 OD < 17,1 mm – 515; OD < 17,1 mm – 205; 35
OD > 17,1 mm – 485 OD > 17,1 mm – 170

 

ASTM A312 Stainless Steel Pipes Mechanical Properties
Material Heat
Treatment
Temperure
Min.
º F(º C)
Tensile Strength
Ksi (MPa), Min.
Yield Strength
Ksi (MPa), Min.
Elongation %, Min
TP304 Solution 1900 (1040) 75(515) 30(205) 35
TP304L Solution 1900 (1040) 70(485) 25(170) 35
TP304H Solution 1900 (1040) 75(515) 30(205) 35
TP310S Solution 1900 (1040) 75(515) 30(205) 35
TP316 Solution 1900(1040) 75(515) 30(205) 35
TP316L Solution 1900(1040) 70(485) 25(170) 35
TP316H Solution 1900(1040) 75(515) 30(205) 35
TP316Ti Solution 1900(1040) 75(515) 30(205) 35
TP321 Solution 1900(1040) 75(515) 30(205) 35
TP321H Solution Cold: 2000(1100)
Hot: 1925(1050)
75(515) 30(205) 35
TP347 Solution 1900(1040) 75(515) 30(205) 35
TP347H Solution Cold: 2000(1100)
Hot: 1925(1050)
75(515) 30(205)

 

STAINLESS STEEL PIPES TOLERANCES (ASTM A312)

DIAMETER TOLERANCE OF STAINLESS STEEL PIPES

NPS ASTM A312 OD Tolerance
+
inch mm inch mm
1/8~1 1 /2
> 1 1 /2~4
> 4~8
> 8~18
> 18~26
> 26~34
> 34~48
1/64(0.015)
1/32(0.031)
1/16(0.062)
3/32(0.093)
1/8(0.125)
5/32(0.156)
3/16(0.187)
0.4
0.8
1.6
2.4
3.2
4.0
4.8
1/32(0.031)
1/32(0.031)
1/32(0.031)
1/32(0.031)
1/32(0.031)
1/32(0.031)
1/32(0.031)
0.8
0.8
0.8
0.8
0.8
0.8
0.8

WALL THICKNESS TOLERANCE OF STAINLESS STEEL PIPES

NPS ASTM A312 WT Tolerance, %
+
1/8-2 1 /2 20.0 12.5
3~18, t/D≤ 5% 22.5 12.5
3~18, t/D> 5% 15.0 12.5
≥ 20, welded 17.5 12.5
≥ 20, seamless, t/D≤ 5% 22.5 12.5
≥ 20, seamless, t/D> 5% 15.0 12.5