A heat treatment deformation control method for an aluminum alloy hemispherical shell of an ellipsoidal surface storage tank

Abstract

The invention relates to a heat treatment deformation control method for a large-diameter and large-modulus elliptical molded surface container semispherical shell and belongs to the technical field of container manufacturing. By means of the heat treatment deformation method, due to the fact that an integrated quenching and aging heat treatment tool is designed, the elliptical molded surface container semispherical shell and the heat treatment tool can be tightly matched, the quenching transfer time is shortened, the phenomenon that the top of the shell collapses and pits happen in the circumferential direction of the shell during quenching is avoided, quenching and time aging deformation is reduced, and therefore the heat treatment performance of the elliptical molded surface container semispherical shell can be ensured; and meanwhile, the subsequent machining precision of the shell is also ensured. In addition, a UCON water solution with the concentration ranging from 6% to 10% is adopted in the method to serve as a quenching medium, dynamic flowing of the water solution is maintained, the cooling speed and uniformity of the shell are ensured, meanwhile, quenching deformation is also controlled, and therefore the product precision is ensured.

Description

technical field [0001] The invention relates to a heat treatment deformation control method for a hemispherical shell of a storage tank with a large diameter and a large modulus ellipsoidal surface, which belongs to the technical field of storage tank manufacturing. The modulus means that the ratio of the major axis to the minor axis of the hemispherical shell is not less than 2. Background technique [0002] Foreign countries usually design professional heat treatment equipment to heat treat the hemispherical shell of large storage tanks. For example, the integral spinning bottom of the American AresI rocket fuel storage tank (Φ5500mm) uses special heat treatment equipment for spraying + water quenching; domestic super large rocket fuel storage tanks The bottom of the box (Φ2250mm, Φ3350mm, Φ5000mm) is formed by tailor welding of melon petals. The wall thickness of the melon petal blank is relatively large, and the machining allowance of the bottom of the box after tailor w...

AI Technical Summary

Problems solved by technology

The follow-up machining allowance of the hemispherical shell of the ellipsoidal surface storage tank is small. If the deformation of the shell during the heat treatment cannot be controlled, it will lead to serious deformation of the large port and excessive roundness of the mouth, which will seriously affect the subsequent processing. In addition, the component is an ellipsoidal surface with a large modulus (the modulus is not less than 2), and its structural characteristics cause the small port part of the shell to easily collapse during the quenching process, and pits are prone to appear in the circumferential direction of the shell, that is, The component is directly scrapped due to large deformation

In addition, 2219 aluminum alloy is a quenching transfer time-sensitive alloy, and the quenching transfer time is closely related to its mechanical properties after heat treatment. Generally, the shorter the transfer time, the better, otherwise it will lead to a sharp decline in component strength

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