US 11,813,695 B2
Method for forming large-diameter special-shaped cross section thin-wall tubular part
Zhubin He, Dalian (CN); Shijian Yuan, Dalian (CN); Kailun Zheng, Dalian (CN); Wei Du, Dalian (CN); and Jianshu Liu, Dalian (CN)
Assigned to DALIAN UNIVERSITY OF TECHNOLOGY, Dalian (CN)
Filed by DALIAN UNIVERSITY OF TECHNOLOGY, Dalian (CN)
Filed on Dec. 6, 2019, as Appl. No. 16/705,416.
Prior Publication US 2021/0114140 A1, Apr. 22, 2021
Int. Cl. B23K 26/24 (2014.01); B23K 20/12 (2006.01); B23K 37/00 (2006.01); B23K 101/18 (2006.01)
CPC B23K 26/24 (2013.01) [B23K 20/122 (2013.01); B23K 37/003 (2013.01); B23K 2101/185 (2018.08)] 5 Claims
OG exemplary drawing
 
1. A method for forming a large-diameter special-shaped cross section thin-wall tubular part, comprising the steps of:
(1) performing feature analysis on a target part by determining a shape of a prefabricated barrel blank, and determining a position and dimension of a tailor weld joint on the prefabricated barrel blank, thereby forming a target part;
(2) cutting a plate blank and rolling the plate blank into a barrel shape;
(3) tailor welding the plate blank rolled in step (2) into a barrel blank, wherein a radial cross section of the barrel blank is closed;
(4) pre-deforming the barrel blank obtained in step (3);
(5) performing hot air pressure bulging on a pre-deformed barrel blank obtained in step (3) so that the pre-deformed barrel blank bulges and deforms and abuts against a die cavity, thereby obtaining a tubular part with a contour required for the target part;
(6) performing thermal treatment on the tubular part obtained in step (5);
(7) removing the tailor weld joint by laser cutting on a thermally-treated tubular part obtained in step (6);
(8) performing butt joint tailor welding on the thermally-treated tubular part after the removal of the tailor weld joint; and
(9) correcting and polishing the tubular part obtained by butt joint tailor welding to finally obtain the target part;
wherein in step (5), a compressed gas with a pressure of 10-50 MPa is introduced into a tailor welded barrel blank so that the barrel blank is bulged within a time period of 30-100 s and abuts against the die cavity to obtain a contour required for the target part;
wherein in step (6), the thermal treatment conditions are: a solution temperature of 510-540° C., a time of 3.0-4.5 h, cooling by water quenching, an aging temperature of 180-210° C., and a time of 1.5-2.5 h; and
wherein in step (7), a width of a removed portion of the tubular part is 1-2 mm wider than that of a weld nugget zone of the tailor weld joint; and a cut weld joint area is cooled by liquid nitrogen or cold air to ensure a temperature of a weld joint area is below 100° C.