ASTM A252 is the standard specification for welded and seamless steel pipe piles. It covers the nominal wall thickness of cylinder shape steel pipe, rectangular pipe is not included. These round pipes are used for piling purposes, playing as a permanent role of load carrying and bearing the pressure. Further more, to act as a tank shell to fill with the concrete piles at sight of the project. 

This standard stated the values units in inch-pound (also could be translated to SI units), which provides the reference A252 pipe data to engineer or designer, for a strength base of the constructions.

The standard has a limit for element P (phosphorous) maximum 0.050%, since P will make steel fragile, and most important is not good for welding performances. ASTM A252 standard specifications only defines the conten of phosphorous, other elements accord with general carbon steel material.