Study on Metal Flow Accumulation Defect as Occurring with Large- sized Stainless Steel Tube during Internal Spinning Formation Process

The Abaqus finite element software is used to simulate and analyze the metal flow buildup phenomenon of the large sized stainless steel pipe as occurring during the process of internal spinning formation process. Using the singlefactor control method,discussions are made on the change regularities of the equivalent strain,the metal flow and the rolling force of the Φ508 mm stainless steel tube during the 3-wheel internal spinning process under the conditions that the tube's wall thickness is 20 mm,12 mm and 7 mm respectively. And flowing velocity of the interlayer metal particles in case of different wall thickness of the tube is analyzed,and thus the reason for the metal flow accumulation is identified. As a result,it is revealed that along with the continuous reduction of the initial wall thickness value,in case of 7 mm wall thickness,the metal accumulation as formed in front of the spinning wheel is high up to 9 mm,while the equivalent strain value of the contact area reaches the maximum value of 7.9,and spinning rolling force is up to 450 kN. Therefore it is obvious that under the same working conditions,the lighter the wall thickness,the bigger the equivalent strain value of the contact area,and the bigger the spinning force as needed,which leads to the more serious metal buildup phenomenon.