In our lives, no matter where we are, we can see steel-insulated steel pipes. However, everyone’s understanding of steel pipes is really narrow, and there is only one kind of steel pipe.In fact, there are two types of steel pipes used in our lives, namely, steel sleeve steel insulation steel pipes

6. GB9948-1988 (seamless steel pipe for petroleum cracking). Mainly used in boilers, heat exchangers and fluid pipelines of petroleum smelters. Its representative materials are 20, 12CrMo, 1Cr5Mo, 1Cr19Ni11Nb, etc.7. Steel pipes for geological drilling (YB235-70) are steel pipes used for core drilli