The mechanical properties of galvanized pipes should meet the requirements of GB-3092. The mechanical properties of steel are important indicators to ensure the final properties (mechanical properties) of the steel, which depend on the chemical composition of the steel and the heat treatment system. In the steel pipe standard, the tensile properties (tensile strength yield strength or yield point elongation) and hardness toughness index are specified according to different application requirements, as well as the high low temperature performance required by users.
Galvanized pipes with a nominal diameter of not more than 50 mm shall be subjected to a cold bending test. The bending angle is 90°, and the bending radius is 8 times the outer diameter. The test should be carried out without filler, and the weld of the specimen should be placed on the outside or upper part of the bending direction. After the test, there should be no cracks in the sample, and the phenomenon is the same as the peeling of the zinc layer.
The galvanized pipe shall be tested for the uniformity of the galvanized layer. The galvanized pipe sample shall not turn red (copper plating) by immersing it in a copper sulfate solution for 5 consecutive times.
