Partition electromagnetic forming method and forming device for bellows

Abstract

The invention relates to a partition electromagnetic forming method and forming device for a corrugated pipe. The method comprises the following steps that S1, a radial electromagnetic area and a thermoforming area which can move in the axial direction of the pipe are correspondingly arranged inside and outside the pipe; S2, the thermoforming area is moved a position to be formed at one end of thepipe fitting; S3, the thermoforming area is heated to soften the position to be formed, within the thermoforming area, of the pipe fitting; S4, the radial electromagnetic area is moved to a positioncorresponding to the thermoforming area; S5, the radial electromagnetic area discharges to form radial electromagnetic force, so that the position to be formed of the pipe fitting expands into the thermoforming area to form an expansion corrugated joint; S6, the thermoforming area is moved to the next position to be formed of the pipe fitting; and S7, a loop from the third step to the sixth step keeps going after being carried out till forming is completed. The device comprises a radial bulging coil and a thermoforming die which can move axially, wherein the radial bulging coil and the thermoforming die are correspondingly arranged in the radial electromagnetic area and the thermoforming area. The partition electromagnetic forming method and forming device have the beneficial effects of easy operation, easy realization, stability and reliability.

Description

technical field [0001] The invention mainly relates to the technical field of high-speed forming in plastic processing of materials, in particular to a partitioned electromagnetic forming method and forming device for corrugated pipes. Background technique [0002] Wave expansion joints are key components in modern industrial equipment and pipe networks. They have the functions of displacement compensation and external force absorption. The metal bellows is a key component of the corrugated expansion joint, and the metal bellows can induce progressive folding, so that the folding mode of the metal thin-walled pipe can be precisely controlled when it is crushed. The more folds, the better the cushioning and energy absorption. As a cylindrical thin-walled elastic shell with transverse corrugations, the metal bellows can undergo large deformation under the action of axial force, lateral force and bending moment, so the metal bellows can adapt to high strength, large deformatio...

AI Technical Summary

Problems solved by technology

However, this method has the following two problems: (1) Multiple wave expansion joints require multiple molds to be used in combination; (2) During the hydraulic bulging process, the pipe fittings are not subjected to axial pressure, and the bulging height of the wave expansion joints is low. The thinning rate of the expansion joint is large; (3) Hydroforming is a static forming method. Compared with high-speed dynamic deformation, the forming limit of the material is low

However, this method has the following problems: (1) A set of integral molds are used for forming multiple wave expansion joints, so after the pipe fittings are bulged, the mold cannot move in the axial direction to compress the wave expansion joints axially; (2) because there is no axial Electromagnetic force, the wave expansion joint is pure bulging deformation

Therefore, the thinning rate of the corrugated expansion joint is large, resulting in a low bulging height; (3) For the one-time overall forming of the difficult-to-deform, large-size bellows, large-scale equipment is often required to provide electromagnetic force

Images