Galvanized steel pipes with threaded delivery, threads should be made after galvanizing. The thread must comply with the YB822 regulations.
The mechanical properties of the galvanized steel pipe and the weight of the galvanized layer, the mechanical properties of the steel pipe before galvanizing shall comply with the provisions of GB3092. The weight of the galvanized layer should be not less than 500g/m2.
The hydraulic test and surface quality of galvanized steel pipe, test pressure and eddy current test comparison sample size shall comply with the national standard GB3092. The surface of the galvanized steel pipe should have a complete layer and no black spots and bubbles that are not plated with zinc. It is allowed to have a rough surface and a local zinc tumor.
