Welding method for corner weld joint of Q690qD bridge steel box type rod piece

Abstract

The invention discloses a Q690qD bridge steel box type rod piece corner weld joint welding method which comprises the steps that grooves are symmetrically machined in the two long sides of a web, the grooves are single-side double-V-shaped grooves with truncated edges, and the truncated edges of the single-side double-V-shaped grooves are 2-6 mm thick; the angle of the upper V-shaped groove is 10-15 degrees; the angle of the lower V-shaped groove is 45-55 degrees; the depth of the lower V-shaped groove is 15 to 28 mm; the cover plate and the web plate are assembled into a box type rod piece, positioned welding is conducted in the groove, and the cover plate and the web plate are connected together; the formed box type rod piece is turned over rightwards by 90 degrees, and two edge and corner weld joints on one side of the box type rod piece are welded; and the formed box type rod piece is turned over rightwards by 180 degrees, and then two corner angle welding seams on the other side of the box type rod piece are welded. According to the method, the manufacturing problems in the aspects of assembling, welding and the like of the box type rod piece are solved, the welding quality is guaranteed, and welding deformation is controlled.

Description

technical field [0001] The invention belongs to the technical field of bridge manufacturing, and in particular relates to a welding method for edge and corner welds of Q690qD bridge steel box-shaped members. Background technique [0002] The steel truss girder bridge is a structural form in which the solid-web steel plate girder bridge is hollowed according to certain rules. The structure as a whole is the stress mode of the girder. type rod. The box-shaped design of the main truss member cover plate and web plate thickness are usually in the range of 30mm ~ 60mm, the edge and corner welds between the cover plate and the web plate are mostly single-sided partial penetration welds, and the edge and corner weld bevels are blunt ≥ 2mm. . [0003] In recent years, with the vigorous development of bridge construction, steel truss girder bridges have also promoted the development of high-performance steel for bridges while pursuing lighter weight and larger span. Steel with a yi...

AI Technical Summary

Problems solved by technology

However, compared with other low-strength bridge steels, the weldability of Q690qD grade steel is poor, and the requirements for welding environment and welding process are more stringent, and because the Q690qD steel rolling process is the particularity of TMCP+tempering, Q690qD steel is deformed during welding. The temperature of the final heat correction should not exceed 600°C. Using a higher temperature for heat correction will reduce the yield strength, tensile strength, elongation and other mechanical properties of the steel to varying degrees.

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