The hardness test of the seamless pipe should take into account its mechanical properties, which is related to the performance and quality of deformation, stamping, cutting and other processing using stainless steel as raw material. Therefore, all seamless steel pipes should be tested for mechanical properties. There are two main types of mechanical property testing methods, one is tensile test and the other is hardness test.

Seamless steel pipes are composed of various elements in steel. These elements are combined in different proportions to form different mechanical properties of seamless steel pipes. The amount of any element will directly affect the mechanical properties of seamless steel pipes.

The basic reasons for defects in cold drawn seamless steel pipes are:

The size tolerance of seamless steel pipe is mainly the diameter tolerance and wall thickness tolerance.

1. The fixed-length spiral steel pipe may not be bundled.2. If there are threaded buckles at both ends of the spiral steel pipe, it should be protected by a thread protector. Apply lubricating oil or anti-rust agent to the threaded fasteners. Both ends of the spiral steel pipe are breached, and nozzle protectors can be added at both ends according to requirements.

Straightening is an important process in the production of seamless and welded steel pipes. Especially API standard oil casing and oil and gas pipes, steel casing pipes and special pipes for mechanical equipment, which have high quality requirements.These kinds of steel pipes not only have strict requirements on steel grade and weld quality, but also have high requirements on straightness of steel pipes.