ASTM A213 Standard Specification for Seamless Ferritic and Austenitic Alloy-Steel Boiler, Superheater, and Heat-Exchanger Tubes.

This specification covers seamless ferritic and austenitic steel boiler, superheater, and heat-exchanger tubes, designated Grades T5, TP304, etc. 

The tubing sizes and thicknesses usually furnished to this specification are 1/8 in. [3.2 mm] in inside diameter to 5 in. [127 mm] in outside diameter and 0.015 to 0.500 in. [0.4 to 12.7 mm], inclusive, in minimum wall thickness or, if specified in the order, average wall thickness. Tubing having other diameters may be furnished, provided such tubes comply with all other requirements of this specification.

ASTM A213 Grade

Yield Strengt


Tensile Strength




Flattening Test
Flaring Test
Grain Size

TP304H TP304L 

TP321H TP317

TP310S TP304 

 TP321 TP347H 


TP316 TP316L 

H=1.09t/(0.09+t/D) and
check if the tube has cracks. 

Acc. to ASTM A450
H steel grade ≦ Grade 7