METHOD FOR THINNING AND FORMING INNER WALL OF ELONGATED HOLLOW TUBE

• Main Authors: XIA Yingxiang, WANG Jitai, WANG Ying, YIN Anmin, ZHANG Song, YE Caoqi, SHU Xuedao, XU Haijie, LI Zixuan, ZUO Jinrong
• Format: Patent
• Language: English
• Published: 08.12.2022
• Subjects: AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKINGWITHOUT ESSENTIALLY REMOVING MATERIAL; MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES,OTHERWISE THAN BY ROLLING; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; PERFORMING OPERATIONS; PUNCHING METAL; TRANSPORTING

The present invention discloses a method for thinning and forming an inner wall of en elongated hollow tube, including the following steps performed by a spinning machine and a three-roll skew rolling mill: first, locally thinning the inner wall of the elongated hollow tube on the spinning machine by using an internal spinning process, such that an end of the elongated hollow tube has a wall thickness greater than that of a middle section of the elongated hollow tube; and then machining an outer wall of the machined elongated hollow tube on the three-roll skew rolling mill by using a skew rolling process, so as to reduce a positioning outer diameter of the end of the elongated hollow tube to form a necking. Due to the fact that the elongated hollow tube is first locally thinned, and a necking process is then performed on the end, the present invention has the following advantages: a necked portion of a part can meet a requirement for a thickening amount, the whole part can be cold-formed without the need for cutting a blank, and the material utilization rate is high.