Processing method of universal joint precision forging with R arc end faces

Abstract

The invention provides a processing method of a universal joint precision forging with R arc end faces. The processing method comprises the steps of blanking, shot blasting, surface coating, blank heating, forging, quick air cooling after normalizing, shot blasting, phosphorus saponification and cold extrusion forming. Circular arc cold extrusion forming structures are arranged at the parts, corresponding to R arcs of the end faces of the universal joint, of a cold extrusion forming mold. According to the processing method of the universal joint precision forging with the R arc end faces, an original processing technology is improved, during final universal joint cold extrusion forming, circular arc cold extrusion forming surfaces are arranged at the parts, corresponding to the R arcs of the end faces of the universal joint, of the cold extrusion forming mold, and besides, two rods of the universal joint are formed at a time in a forward extrusion mode by virtue of the extrusion mold,so that the metal streamline distribution situation of the forging is excellent, quality of the forging is higher, follow-up machining is not required, and a prepared product is high in strength and excellent in anti-twisting property.

Description

technical field [0001] The invention relates to the technical field of metal machining, in particular to a machining method for a precision forging universal joint whose end face is a circular arc without machining. Background technique [0002] Forging is a processing method that uses forging machinery to exert pressure on metal blanks to cause plastic deformation to obtain forgings with certain mechanical properties, certain shapes and sizes. Forging can eliminate defects such as loose casting of metals during the smelting process, optimize Microstructure, while preserving the complete metal streamline, the product has excellent strength and torsion resistance. Such as figure 1 Shown is a universal joint 10 whose end face is an R-arc (arc 101). The generally used forging process steps are: blank blanking, shot blasting, heating, warm forging, shot blasting, normalizing, phosphorus saponification, cooling Extruded and face machined R-arc 101. The disadvantage of adoptin...

AI Technical Summary

Problems solved by technology

The disadvantage of using this existing technology is that the end face of the universal joint has a sharp angle with the maximum outer diameter after cold extrusion, and there are fine cracks, so the end face must be turned by machining, while the arc of the forged end face is After machining, the metal flow line is destroyed, which reduces the metal strength of the product and the torsion that the product can withstand, and obviously shortens the service life of the product; in addition, due to the damage of the forging surface after machining, phosphating and anti-rust treatment is carried out in the subsequent sequence Compared with the original so-called forged surface, the anti-rust effect will be shortened by more than 30%.

[0003] In an improved production process of universal joints, in order to effectively control the wall thickness difference of the inner cavity and the beating of the rods, it is usually arranged to preform the rods as the first process, and the preforming of the two rods It is carried out in two forward extrusion steps. Judging from the final test results of the actually produced parts, quality problems are more likely to occur at the connecting arc of the large rod of the universal joint, and the strength is not enough, and fatigue damage is prone to occur.

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