Processing welding technique of large closing end

Abstract

The invention discloses a machining and welding process of a large sealed head. The machining and welding process comprises the following steps: 1) a lobe die is machined; 2) a lobe is punched for forming; 3) a welding groove of the lobe is made, assembled and welded; and a smooth curve is drawn between the lobe generatrix and the sealed head vertex after assembling and welding; a machining die of a top round plate is made according to the smooth curve, and the top round plate is formed by pressing the machining die; the welding groove is machined; the top round plate and the lobe are welded.The machining and welding process of the large sealed head has simple operating steps, and can eliminate the deformation near a butt seam, and the sealed head welded by the machining and welding process has nice appearance and good stress.

Description

technical field [0001] The invention relates to the fields of metal processing and pressure welding, in particular to a processing and welding process for large-scale heads. Background technique [0002] At present, since the head is the key pressure-bearing part of the pressure vessel, the quality of the head directly affects the use of the container, so the large head cannot be directly pressurized and welded like the traditional small head, but divided into several parts. Partly assembled, spliced ​​and welded. The traditional process of the traditional large-scale head is: 1. Stamping the petals and the top circular plate separately; 2. Welding the petals into a part of the head; Splice welds. In the traditional process, the shape of the stamping forming of the top circular plate and the stamping forming of the petals are coordinated with each other. However, when the petals are assembled and welded into a part of the head, the residual stress during stamping is releas...

AI Technical Summary

Problems solved by technology

In the traditional process, the shape of the stamping forming of the top circular plate and the stamping forming of the petals are coordinated with each other. However, when the petals are assembled and welded into a part of the head, the residual stress during stamping is released and welded due to welding heating. Thermal expansion and contraction during the cooling process make it difficult to control welding deformation. These factors cause changes in the shape of the petals, which in turn make the shape of the petals and the top circular plate prone to sudden changes in the vicinity of the splicing weld, which not only affects the appearance, but also makes the The local stress at the sudden change in shape increases, and there is no requirement for the use of mechanical equipment after assembly, which affects the use or service life of the head

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