At present, the most widely used spiral steel pipe material on the market is Q235B, mainly because Q235B material is relatively affordable and its performance is suitable for many industries, but in some special industries, high-performance materials such as Q345 and L360 are also used.

The main materials of the spiral steel pipe are: Q235A, Q235B, 20#, Q345 (16Mn), L245 (B), L290 (X42), L320 (X46), L360 (X52), L390 (X56), L415 (X60), L450 (X65), L485(X70), L555(X80), L290NB/MB(X42N/M), L360NB/MB(X52N/M), L390NB/MB(X56N/M), L415NB/MB(X60N/M), L450MB(X65), L485MB(X70), L555MB(X80).

Q235B consists of Q+number+quality grade symbol+deoxygenation method symbol. Its steel number is prefixed with “Q”, which represents the yield point of the steel, and the following number represents the yield point value in MPa. For example, Q235 represents a carbon structural steel with a yield point (σs) of 235 MPa.

Q345 is a kind of steel material. It is a low alloy steel, “Q” means yield strength, Q345 means that this steel has a yield strength of 345MPa. Q345 decreases its yield value as the thickness of the material increases. And the domestic product may be less than 345, so the strength must be less than 345 in the mechanical design, otherwise there will be problems.

API5l X52 Petroleum Line Pipe API5L Standard, Standard: API 5L – American Petroleum Institute Standard (PSL1, PSL2) GB/T9711 – China National Standard (GB/T9711.1, B/T9711.2).