Multi-stage tube hydroforming process

摘要

A method for hydroforming a tubular blank comprising the steps of at least partially closing the die portions of a die about a tubular blank, introducing a hydraulic fluid into the tubular blank at a first pressure, substantially closing the die portions about the tubular blank, partially opening the die while at least initially maintaining the pressure of the hydraulic fluid, and substantially closing the die portions at least a second time.

主权项

1. A method for hydroforming a tubular blank comprising the steps of:
at least partially closing the die portions of a die about a tubular blank disposed in the die; introducing a hydraulic fluid into the tubular blank at a first pressure; substantially closing the die portions about the tubular blank for a first instance to form a first intermediate form tube; partially opening the die by moving the die portions relatively away from one another to form a gap therebetween while at least initially maintaining the pressure of the hydraulic fluid within the first intermediate form tube to allow at least a partial expansion of a cross-section of the first intermediate form tube; and substantially closing the die portions around the first intermediate form tube at a second instance.