What are the technical performance inspections of seamless steel pipes?

　  Seamless steel pipes are divided into hot rolled (extruded) seamless steel pipes and cold drawn (rolled) seamless steel pipes due to their different manufacturing processes. Cold drawn (rolled) tubes are divided into round tubes and shaped tubes. The process performance inspection of seamless pipes can be tested through four aspects: hydraulic (water) pressure test, flattening test, bending test, and flaring test, to check the applicability of the quality of the steel pipe in the subsequent processing process. Commonly used process performance tests include water pressure, flattening, bending, flaring test, etc.

　　 1. Liquid (water) pressure test: the test steel pipe is filled with water of a certain pressure, and the pressure is maintained for a certain time (the test pressure value and the pressure stabilization time are determined according to the standard), and there is no leakage. This test is a non-destructive test and is commonly used for full inspection of products.

　　 2. Flattening test: Put the steel pipe sample between the two flat-plate fixtures, apply force between the fixtures so that the spacing reaches the standard specified value, and check the sample deformation area for cracks, cracks and other defects.

　　 3. Bending test: Put the steel tube sample on the bending test machine, and bend to the angle required by the standard according to the bending core radius specified by the standard. The surface of the bending position has no defects such as cracks or cracks.

       4. Flaring test Place the steel pipe sample on the work surface with the opening upward, and press the top core selected according to the standard taper into the steel pipe until the test outer diameter flaring rate reaches the standard, the sample surface has no cracks or Cracks and other defects.