Electron beam welding method for lock butt joint of large-size thin-wall titanium alloy storage tank

Abstract

The invention provides an electron beam welding method for a lock butt joint of a large-size thin-wall titanium alloy storage tank. The electron beam welding method comprises the steps that a fuel hemispherical shell and a fuel rear frame are welded; a common-base partition plate and a fixing ring are welded; storage tank workpieces are assembled, clamped and positioned; the storage tank workpieces are positioned and welded; and the storage tank workpieces are welded and formed, wherein during first two welding, a lock is subjected to complete-penetration welding in an electron beam welding mode in a part state, in subsequent welding, all parts are assembled and positioned together and then subjected to electron beam welding, effective penetration of a weld joint is guaranteed, but the complete penetration of the lock cannot be achieved, and splashing on the back is avoided. By adopting an optimized tool and welding process, the effective weld width and the pressure bearing capacity ofthe root of the electron beam welding seam lock of the lock butt joint of the large-size thin-wall titanium alloy storage tank are effectively improved, the phenomena that X-ray inspection air hole defects are extremely likely to occur in a welding seam and the welding seam part is cracked in the hydraulic test process are avoided, the number of rewelding times is reduced, the production efficiency is improved, and the production cost is reduced.

Description

technical field [0001] The invention belongs to the field of welding technology, and relates to a welding method for a large-scale thin-walled titanium alloy storage tank, in particular to an electron beam welding method for a bottom-locked butt joint of a large-scale thin-walled titanium alloy storage tank. Background technique [0002] The surface tension storage tank belongs to the large-scale thin-walled titanium alloy surface tension storage tank, such as figure 1 As shown, the storage tank includes a fuel hemispherical shell, a fuel rear frame, a fuel bulkhead ring, a fuel barrel section, a common bottom bulkhead, a fixed ring, an oxygen bulkhead ring, an oxygen reinforcing frame, and an oxygen upper hemispherical shell from top to bottom. The components are welded and fixed by locking bottom butt joints. During electron beam welding of butt joints of large-size thin-walled titanium alloy storage tanks, due to the unreasonable welding sequence, the butt joints welded ...

AI Technical Summary

Problems solved by technology

During electron beam welding of butt joints of large-size thin-walled titanium alloy storage tanks, due to the unreasonable welding sequence, the butt joints welded first will affect the butt joint state of the butt joints welded later, so that the gap and misalignment of the butt joints welded later become larger , and the selected electron beam welding parameters are more sensitive to the butt gap and dislocation before welding, and the larger butt gap and dislocation have a greater impact on the selection of electron beam welding parameters and the determination of welding results

After the electron beam welding of the storage tank is completed, during the hydraulic test, if the effective penetration depth of the weld is insufficient, cracking of the electron beam weld is prone to occur, resulting in the need for rework or scrapping of the product, which increases the production cost and reduces the production efficiency

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