General oil and gas pipelines, such as API 5L, GB/T 9711-2011,all have requirements on sizing rate or expanding rate, which should be between 0.3- 1.5%. The sizing rate or expanding rate mainly ensures the pipe diameter and ellipticity of the steel pipe, and then improves the yield strength of the steel pipe (Bauschinger effect). If the yield strength of steel pipe is low, a larger expansion rate can be selected to improve the yield strength.