METHOD FOR PRESSING CHANNEL SECTION WITH BENDING ANGLE SMALLER THAN OR EQUAL TO 90 DEGREES

摘要

Disclosed is a method for pressing a channel section with a bending angle being smaller than or equal to 90 degrees, wherein an upper male die and a lower female die are used for processing; the male die comprises an expansion sleeve (the external part having a narrower top and a wider bottom, hereinafter referred to as a sleeve body) and an expansion core (hereinafter referred to as a core body) which are nested with each other, at least one of a central hole of the sleeve body and the core body is a wedge with a larger top and a smaller bottom, and a relative locking mechanism is arranged therebetween; the female die comprises a multi-petal-shaped inner female die (the groove having a wider top and a narrower bottom) and an external female die which are in elastic connection; a pressure is continuously applied to a pressing machine of the male die to make the pressing machine move downward, the male die then moves downward, the sleeve body firstly comes into contact with a workpiece, then the core body moves downward relative to the sleeve body to extend the sleeve body, the male die bends and presses the workpiece into a groove of an inner female die, the inner female die moves downward when the resistance of an elastic body at the bottom of the inner female die is exceeded, and when the termination point of the bottom of the outer female die is reached, a pre-set workpiece is formed; and the elastic body at the bottom of the inner female die restores in an elastic mode, the inner female die is bounced up, the expansion core and sleeve move relatively to return to the original states, and a stamping mechanism takes the male die out of the female die after the elastic body completely restores, such that the workpiece is taken out. Die processing overcomes defects existing in the traditional techniques.