Stress control production process of high-strength aluminum alloy pipe

Abstract

The invention relates to a stress control production process of a high-strength aluminum alloy pipe. The stress control production process comprises the steps that a, an extrusion mold is selected, the surface and size of the extrusion mold are checked before installing, and the roundness tolerance of the mold cannot exceed 0.10 mm; b, the extrusion mold is preheated, and the extrusion mold and an extrusion barrel are preheated to 400 DEG C-450 DEG C; c, an aluminum alloy hollow round ingot casting blank is preheated, an ingot casting is preheated to 400 DEG C-450 DEG C, and the temperature difference of the head and tail of the ingot casting is controlled to be smaller than or equal to 30 DEG C; d, the ingot casting blank is placed in the mold, extrusion is started, the extrusion speed is smaller than or equal to 1.0 mm/s, and the difference of a long shaft and a short shaft of the extruded pipe is smaller than 2.50 mm; e, roll pre-straightening is carried out on a straightening machine; f, offline quenching is carried out, the pipe is quenched through vertical quenching equipment, during charging, aluminum wires are bound at the upper and lower proper positions of the pipe to reduce longitudinal bending generated after quenching, and a penetrating rod is used for increasing the contact area and balancing the stress on the two sides of the wall thickness of the pipe; and g, stretcher straightening finishing is carried out, profiling stretch core cushions are arranged in the two ends of the pipe, an arc-shaped stretch jaw is used for carrying out tension stretching on the pipe, and the stretch rate is controlled to be 1.0%-3.0%.

Description

technical field [0001] The invention belongs to the technical field of extrusion and cold processing of high-strength aluminum alloy pipes, and in particular relates to a stress-controlled production process of high-strength aluminum alloy pipes. Background technique [0002] High-strength aluminum alloy thin-walled pipes have been widely used in aviation, aerospace, electrical, communication, electronics, atomic energy, transportation and other industrial fields due to their light weight, strength, high rigidity, and compact structure. [0003] At present, the usual production process of high-strength aluminum alloy large-size thin-walled hot-extruded pipes is that the pipes are extruded and quenched, and then directly delivered after tension straightening or roller straightening. Namely "extrusion→quenching→tension straightening→delivery" or "extrusion→quenching→roller straightening→delivery". However, the size or surface of these seamless pipes after extrusion often cann...

AI Technical Summary

Problems solved by technology

However, the size or surface of these seamless pipes after extrusion often cannot meet the requirements for direct use, and usually requires subsequent secondary machining to meet the precise surface and size requirements. In this way, it is found that the products produced by the existing process route are often After machining, there are problems such as pipe deformation, wall thickness eccentricity, ellipse, etc., which are the performance of large internal stress of the pipe.

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