On the base of the Tube of hydroforming technology, the hydroforming process of subframe usually consist of the process of tube pre-bending pre-expansion and/or preforming and final hydroforming.

• 根据目前管材液压成形技术的水平，可以采用管材经过预弯、预液压胀形、终液压胀形等工艺过程，实现副车架本体的液压成形。