A Rapid Prediction Method for Pipe Hydroforming

Abstract

The invention relates to a rapid prediction method for tube hydroforming. The method comprises the following steps that meshes are formed on the outer surface of a tube blank and the forming surface of a mold, nodes of the meshes on the tube blank axially displace along the tube blank according to the preset tube blank axial feed amount; the displaced nodes of the meshes on the tube blank are sequentially projected on the forming surface of the mold in the normal direction of the nodes so as to adopt the projected meshes on the tube blank as an initial solution, and a final configuration of the tube blanks is solved through a finite element method; the estimated thickness of the meshes on the outer surface of each tube fitting is calculated to obtain the actual thickness of the nodes of the meshes of the outer surfaces of the tube fittings, meshes on the inner surfaces of the tube fittings are generated, and finally the hydroformed tube fittings are obtained. According to the method, the performance parameters obtained after tube hydroforming can be rapidly predicted, so that constant technological adjusting and research can be performed, the production cost is saved, and the production time is shortened.

Description

technical field [0001] The invention relates to a rapid prediction method for pipe hydraulic forming, which belongs to the technical field of pipe forming. Background technique [0002] With the continuous development of the national economy, the competition in the manufacturing industry of automobiles, airplanes and other vehicles is becoming more and more fierce. Due to the advantages of light weight, integration and high flexibility of the products, the hydroforming of pipes has been rapidly improved in the production process. develop. [0003] The principle of pipe hydroforming is as follows: figure 1 As shown, first put the tube blank 2 into the lower mold 4, close the upper mold 1 and the lower mold 4, then fill the inside of the tube blank 2 with a liquid medium to generate hydraulic pressure P, and finally feed it by the axial punch 3, The two ends of the tube blank 2 are sealed, and at the same time, the tube blank is deformed by applying axial thrust or displacem...

AI Technical Summary

Problems solved by technology

The above-mentioned incremental method needs to construct multiple intermediate states of deformation between the tube blank and the pipe fitting during the simulation, and the two adjacent states need to be simulated by the finite element method. Therefore, not only the setting is complicated, but the use requirements are high. The amount is too large, it takes too long, and it often takes several hours or even days to complete. In the initial stage of hydroforming process design, it does not have much practical value

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