Abstract: There exist a big problem related to the process of flux leakage detection with spiral forward movement of the steel pipe,i.e.,it is so difficult to identify the contact point between the moving pipe and the driving double rollers,which in turn leads to the difficulty finding out the pitch via the geometric solution method. The movement simulation software of ADAMS is used to calculate and analyze the spiral forward movement of the steel pipe. And then relevant testing apparatus is built up to verify the result of the simulation,and get the steadiness of the pipe movement analyzed. To fix the problem of obvious mechanically-fluctuated movement of the pipe driven by the double rollers as directly beveled,the roller profile is optimized. With such a solution,the pitch of the pipe's forward spiral movement is identified via rather quick and accurate calculation. Moreover,thanks to the optimized roller profile,the magnetic noise as caused by the said mechanical fluctuation is reduced,and thus,the signal-to-noise ratio produced with the flux leakage detection operation is increased.