The quality of tube billet is the main factor to judge the quality of seamless pipe. In order to ensure the reasonable progress of the perforating process and obtain high quality seamless steel tubes, it is necessary to make strict requirements for the geometrical size of the tube, the microstructure and the low magnification of the surface.
Too large diameter or too large oval shape will make the condition of perforation worse. At the same time, it will cause compression deformation due to the large diameter.
The key internal organizations are shrinkage and central porosity, non-metallic inclusions, and gas accumulation. The strictness of this requirement varies with the use of seamless steel tubes and steel grades.
The most important thing is the surface quality of the tube, because in the steel tube billet to any disabled city seamless tube product, often misplaced sites lead to stress concentration, plastic deformation will deepen and extend the difference.
To sum up, in order to produce high quality seamless pipe products, high quality pipes are very important for the first step.