ASTM A 632 Seamless and Welded Austenitic SS Tubing

ASTM A632 Specification for Seamless and Welded Austenitic Stainless Steel Tubing (Small-Diameter) for General Service

Chemical Requirements

Element Composition, %
TP 304 TP 304L TP 310 TP 316 TP 316L TP 317 TP 321 TP 347 TP 348
S30400 S30403 S31000 S31600 S31603 S31700 S32100 S34700 S34800
Carbon, max 0.08 0.03 0.15 0.08 0.03 0.08 0.08 0.08 0.08
Manganese max 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00
Phosphorus, max 0.045 0.045 0.045 0.045 0.045 0.045 0.045 0.045 0.045
Sulfur, max 0.030 0.030 0.030 0.030 0.030 0.030 0.030 0.030 0.030
Silicon, max 0.75 0.75 0.75 0.75 0.75 B 0.75 0.75 0.75 0.75
Nickel 8.0–11.0 8.0–13.0 19.0–22.0 11.0–14.0C 10.0–15.0 11.0–14.0 9.0–13.0 9.0–13.0 9.0–13.0
Chromium 18.0–20.0 18.0–20.0 24.0–26.0 16.0–18.0 16.0–18.0 18.0–20.0 17.0–20.0 17.0–20.0 17.0–20.0
Molybdenum ... ... ... 2.00–3.00 2.00–3.00 3.00–4.00 ... ... ...
Titanium ... ... ... ... ... ... D ... ...
Columbium + tantalum ... ... ... ... ... ... ... E E
Tantalum, max ... ... ... ... ... ... ... ... 0.10
A New designation established in accordance with Practice E 527 and SAE J 1086, Practice for Numbering Metals and Alloys (UNS).
B For seamless TP316L tubes, the silicon maximum shall be 1.00 %.
C For welded TP 316 tubes, the nickel range shall be 10.0–14.0 %.
D Grade TP 321 shall have a titanium content of not less than five times the carbon content and not more than 0.60 %.
E Grades TP 347 and TP 348 shall have a columbium plus tantalum content of not less than ten times the carbon content and not more than 1.0 %.


Tensile Requirements

Tensile strength, min, ksi (MPa) 75 A (515) A
Yield strength, min, ksi (MPa) 30 A, B (205) A, B
Elongation in 2 in. or 50 mm, min, % 35 B

Permissible Variations in Dimensions

Outside Diameter Range

 Outside
Diameter,
in. (mm)		 Inside
Diameter,
in. (mm)		 Wall, plus 
and minus, %
Up to, but not including 3⁄32 +0.002 (0.05) +0.000 10
(0.094) in. (2.38 mm) −0.000 −0.002 (0.05)
3⁄32 (0.094) in. (2.38 mm) but +0.003 (0.08) +0.000 10
−0.000 −0.003 (0.08)
not including 3⁄16(0.188)
in. (4.76 mm)
3⁄16 to, but not including, 1⁄2 +0.004 (0.10) +0.000 10
(0.500) in. (12.70 mm) −0.000 −0.004 (0.10)