1. Seamless Steel Pipe - Seamless steel pipes can be categorized by production methods, including hot-rolled seamless pipes, cold drawn pipes, precision steel pipes, hot-expanded pipes, cold-rolled pipes, and extruded pipes, etc. ⑴ Structural Seamless Steel Pipes (GB/T8162-2008) are used for general structures and mechanical structures. ⑵ Seamless Steel Pipes for Fluid Transportation (GB/T8163-2008) are general seamless steel pipes used for transporting fluids such as water, oil, and gas. ⑶ Low and Medium Pressure Boiler Seamless Steel Pipes (GB/T3087-2008) are used for manufacturing various structural low and medium pressure boiler superheated steam pipes, boiling water pipes, and locomotive boiler superheated steam pipes