Spiral pipe (SSAW) is a welded pipe made of strip steel coil as raw material, extruded at regular temperature, and welded by automatic double-wire double-sided submerged arc welding process.

Longitudinal rolling refers to the rolling method in which the main flow direction of the deformed metal is always the same as the forward direction of the rolled piece during the rolling process, that is, the deformed metal flows along the rolling centerline to the exit of the pipe mill in the deformed pass formed by the rolls.

Thermally expanded seamless pipe is what we often call thermally expanded pipe. Steel pipes with relatively low density but strong shrinkage (seamless steel pipe) can be referred to as thermally expanded pipes. A rough tube finish rolling process that expands the diameter of the tube by cross rolling or drawing.

Anti-corrosion steel pipes refer to steel pipes that have been processed by anti-corrosion technology, which can effectively prevent or slow down the corrosion phenomenon caused by chemical or electrochemical reactions during transportation and use. Generally, it refers to the anti-corrosion treatment of ordinary steel pipes (such as seamless pipes and welded pipes) by special processes, so that the steel pipes have certain anti-corrosion capabilities.

Heat treatment of seamless steel pipe refers to a seamless steel pipe thermal processing process that changes the chemical composition and organization of the surface or interior of the seamless steel pipe to obtain the required properties by means of heating, heat preservation and cooling.

The tensile test is to make a seamless steel pipe into a sample, pull the sample to fracture on a tensile testing machine, and then measure one or several mechanical properties.