What tests should spiral steel pipes go through before leaving the factory

　　The quality inspection method of spiral steel pipe is as follows:

　　1、 Appearance inspection. The appearance inspection of welded joints is a cumbersome and widely used inspection method, which is an important content of inspection. It is mainly to find the defects on the surface of the weld and the deviation in size. After visual inspection, it is inspected with the help of tools such as gauge and magnifying glass. If the appearance of the weld shows defects, there may be defects inside the weld.

　　Therefore, the weld appearance of spiral welded pipe shall not have defects such as arc breaking, burn through, crack, scab, folding, arc pit, etc., and the weld appearance shall be even and regular with smooth transition.

　　2、 Test of physical method: the test method of physics is to measure or test some physical phenomena.

　　The inspection of internal defects of materials or workpieces generally adopts the method of nondestructive testing. Nondestructive testing includes ultrasonic testing, radiographic testing, penetration testing, magnetic testing, etc. Strength test of pressure vessels: in addition to the tightness test, strength test should also be carried out for pressure vessels. There are two common types: hydraulic test and pneumatic test.

　　They can test the weld tightness of vessels and pipelines working under pressure. Pneumatic test is more flexible and faster than hydraulic test.

　　At the same time, the products after the experiment do not need to be drained, which is particularly suitable for the products with difficult drainage, but the risk of the experiment is greater than that of the hydrostatic experiment. When conducting the experiment, we must strictly abide by the corresponding safety technical measures to prevent accidents in the process of the experiment.