Clamping and positioning method for friction welding of steel piston

Abstract

The invention provides a clamping and positioning method for friction welding of a steel piston. A top forging positioning flat surface is designed and machined under a pin seat of a piston skirt part; a pin hole in the pin seat is not machined. The method comprises the concrete steps that a piston head clamps a piston head outer circle by first clamping blocks; a spring jacket is sleeved in a second clamping block at the other end corresponding to friction welding equipment; a middle bushing is sleeved in the spring jacket; the spring jacket is internally shrunk after the second clamping block applies a force; the piston head outer circle is clamped by the middle bushing; the top forging flat surface serves as a top forging support surface in the welding process and force transmission is realized by top forging positioning. The clamping and positioning method has the characteristics that a product size is stable to control, a workpiece is not deformed or damaged and the precise control on the welding quality of the product is realized.

Description

technical field [0001] The invention relates to a steel piston friction welding clamping and positioning method. Background technique [0002] In order to meet the requirement of increasing the explosion pressure of Euro V and Euro VI emission engines to above 20MPa, the traditional aluminum piston cannot meet the requirements, so steel pistons must be used. [0003] A manufacturing scheme for a steel piston with an internal cooling oil passage is to divide the piston into a piston head and a piston skirt, process the upper and lower parts of the internal cooling oil passage in advance, and weld the steel piston through friction welding. The combination of high-quality piston head and steel piston skirt forms the internal cooling oil passage of the piston. [0004] Such as figure 1 The traditional friction welding clamping method shown is as follows: the piston head 1 clamps the outer circle through the first clamping block 3; at the other end corresponding to the friction...

AI Technical Summary

Problems solved by technology

[0005] This method clamps and locates, but because the piston skirt is a hollow shell structure, the irregular surface window structure existing on the outer circle of the piston skirt is an incomplete circumferential surface, and because the skirt wall is thin, the friction welding The clamping positioning method has the following serious problems in practical application:

[0006] (1) The rigid clamping force in the circumferential direction can easily cause the outer circle of the piston skirt to deform and form waste products;

[0007] (2) The axial positioning reference is the lower end surface 2a of the piston skirt. Due to the thin wall, it is deformed during welding and upsetting, so that the overall length of the piston after welding and the coaxiality of the head and skirt cannot be guaranteed;

[0008] (3) After friction welding, the pin hole 2c on the pin seat 2b is severely squeezed and deformed

Images