Forging method of precise deep-hole thin-wall pipe

Abstract

The invention discloses a forging method of a precise deep-hole thin-wall pipe. A rod is sawed for shot blasting, coating and heating by a medium-frequency furnace; then, two times of continuous extrusion of warm forging forward extrusion and warm forging reverse extrusion are performed; and a warm-forged forging is immediately fed in a temperature control cooling furnace by using afterheat to control cooling. The primary thinning stretching is performed on the warm-forged forging after secondary shot blasting and phosphorus saponification to prevent such forging defects as folding and cracking; the punch diameter in the secondary thinning stretching is smaller than the punch diameter in the primary thinning stretching by 0.2-0.3 mm; the transition filleting is performed on the end surface of a punch; the punch diameter in the secondary thinning stretching is larger than the punch diameter in the primary thinning stretching by 0.2-0.3 mm; and the deformation of each thinning stretching is controlled about 25%. The production cycle of thinning stretching, low-temperature annealing, shot blasting and phosphorus saponification is performed on the forging; and a precise deep-hole thin-wall pipe forging with a hole depth-hole diameter ratio of 6 times is obtained generally through 3-4 times of thinning stretching. The method for producing a forged deep-hole long shaft is high in production efficiency, high in utilization rate of raw materials and compact in product materials; and metal streamlines are continuously and symmetrically distributed to improve the product fatigue strength.

Description

technical field [0001] The invention relates to a metal precision forging process, and more particularly relates to a forging method of a precision deep-hole thin-walled tube. Background technique [0002] With the development of society, many spare parts on construction machinery urgently need to adopt new processing methods to meet their requirements for quantity and quality. The shape of deep hole thin-walled long shaft parts is blind hole, and the inner hole is very deep. The hole depth is generally about 6 times the hole diameter. The head is a flat square or hexagonal cylinder. The level of processing, ≤Ra1.6μm. If the traditional processing method is used to manufacture, the head is first hot-forged and then the thin-walled pipe in the deep hole is welded. This process has a long production cycle, high cost, low material utilization rate, and more importantly, the product has low strength and short service life. . Therefore, no matter in terms of cost or product qu...

AI Technical Summary

Problems solved by technology

If the traditional processing method is used to manufacture, the head is first hot-forged and then the thin-walled pipe in the deep hole is welded. This process has a long production cycle, high cost, low material utilization rate, and more importantly, the product has low strength and short service life.

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