Processing method of rectangle fillet bellows expansion joint

Abstract

The invention discloses an expansion joint processing method of a corrugated pipe with rectangular shape and round angle, wherein the manufacturing method comprises the following steps: firstly, the sheet material is processed into a vertical stripe corrugated plate by using a shaping die; secondly, the vertical stripe corrugated plate is processed to a L-shaped or door-shaped buckled corrugated plate by using the shaping die, the round angle at the buckled position is 90 degrees, and the length of a straight edge outside the round angle is no less than 500 mm; lastly, four pieces of L-shaped or two pieces of door-shaped buckled corrugated plates are oppositely welded on the straight edges. The method can avoid the welding seam at the round angle of the corrugated pipe, not only can reduce the welding difficulty, but also can greatly decrease the stress at the round angle, and can be uneasy to be suffered from the fatigue breakdown; by using the method, the production efficiency can be improved, the cost can be reduced, the product quality and the service life can be increased, and the processed expansion joint of the corrugated pipe with rectangular shape and round angle can be used widely in the rectangular conduit to compensate the changes in size.

Description

technical field [0001] The invention relates to a processing method for a metal bellows expansion joint, in particular to a processing method for a rectangular rounded bellows expansion joint. Background technique [0002] Bellows expansion joints are widely used as a compensator for compensating pipes or equipment for dimensional changes caused by thermal expansion and contraction. According to different application occasions, expansion joints can be divided into circular and rectangular. The four corners of bellows in rectangular expansion joints generally have rounded corners, and the processing of rectangular rounded bellows has become the key and difficult point in the processing of rectangular expansion joints. At present, in the processing of rectangular rounded bellows expansion joints, the bellows are usually produced by hydroforming the circular bellows first, and then cutting it into four equally divided rounded parts in the radial direction, and then Each fille...

AI Technical Summary

Problems solved by technology

This processing method has the following disadvantages: 1. It is first processed into a circular corrugated pipe, then cut, and then welded, and there are at least 8 welds, which requires a large workload, low production efficiency, and high cost; 2. Near the rounded corner 3. The forming mechanism of the rounded part is different from that of the straight part, which also leads to increased welding stress and difficult to guarantee welding quality