Welding technology for longitudinal joints of pipe-plug type channel of composite-plate type air cooler

Abstract

Disclosed is a welding technology for longitudinal joints of a pipe-plug type channel of a composite-plate type air cooler. An outer layer of the channel is a base layer, an inner layer of the channel is a coating, each of longitudinal channel joints is formed between each two adjacent perpendicular composite plates, a base layer groove is formed between the base layers, on the outer layer of each longitudinal channel joint, of each two corresponding composite plates, and a coating groove is formed between the coatings, on the inner layer of each longitudinal channel joint, of each two corresponding composite plates. The welding technology includes welding the base layer grooves and the coating grooves sequentially, wherein the base layer grooves are bottomed by argon arc welding and filled with two layers by shielded metal arc welding, the rest parts of the base layer grooves are covered by submerged arc welding, and then the inner coating grooves of the channel are welded on an inner-angle submerged arc welding machine. The welding technology has the advantages that welded joints are high in heat conductivity and small in linear expansion coefficient, channel welding shrinkage distortion amount is small, and welding material cost is reduced substantially; since the base layer grooves and the coating grooves are welded sequentially, the welded joints in the coating grooves can be protected from secondary heating, and corrosion resistance of the welded joints of the coating grooves is improved; production cost is reduced and production efficiency is improved.

Description

technical field [0001] The invention relates to the field of welding technology, in particular to a welding process for a longitudinal seam of a wire plugging pipe box of a composite plate air cooler. Background technique [0002] At present, due to the narrow internal space of the composite panel air cooler, the plug-in pipe box is inconvenient to operate. The conventional welding process for the longitudinal seam of the pipe box is: use a special submerged arc welding machine to weld the inner cladding first, and then weld the electrode arc welding after cleaning the outer root. All welding consumables are made of stainless steel. The main disadvantages of this welding process: 1. The cost of welding materials is high; 2. The base welding is dissimilar metal welding, and the tendency to produce cracks during submerged arc welding is relatively large. Submerged arc welding is not suitable for welding, and the welding efficiency of electrode arc welding is low; 3. The cladd...

AI Technical Summary

Problems solved by technology

[0002] At present, due to the narrow internal space of the composite plate air cooler, the plug-in pipe box is inconvenient to operate. The conventional welding process for the longitudinal seam of the pipe box is: use a special submerged arc welding machine to weld the inner cladding first, and then weld the electrode arc welding after cleaning the outer root. All welding consumables are stainless steel welding consumables

The main disadvantages of this welding process: 1. The cost of welding materials is high; 2. The base welding is dissimilar metal welding, and the tendency of cracks during submerged arc welding is relatively large. Submerged arc welding is not suitable for welding, and the welding efficiency of electrode arc welding is low; 3. The cladding weld is heated twice during external welding, which affects the corrosion resistance of the cladding; 4. Since all stainless steel welding consumables are used, the shrinkage and deformation of the pipe box are relatively large during welding; 5. The time-consuming RT is used for weld flaw detection. Flaw detection, if the time-saving UT flaw detection is used, the flaw detection result will be inaccurate

Images