Based on the test, study and analysis of punching process of the fungoid type punching machine, the advantages of the fungoid type punching improving the quality of the inner and outer surface of rough tubing and the homogeneous wall thickness and enhancing the punching property of heavy alloy materials etc.

To get the law of metal deformation of the work piece being rolled with the cone roll piercing mill, rolling jamming experiment and measurements of wall thickness of different work-piece sizes were conducted, based on which law of the wall thickness variation is calculated and analyzed.

The co-authors describe the need of modification of the plugbar transfer system of the Mannesmann piercing mill located at Seamless Steel Tube Plant,Baoshan Iron & Steel Co.