Once flattening and energy storage capacitor welding method for broad band type thin steel plate connection

Abstract

The once flattening and energy storing capacitor welding process for connecting wide thin steel bands includes vertical overlapping two steel bands to be welded on the planar lower electrode, lowering the upper electrode to densify the overlapped area, once discharging of the energy storing capacitor via the welding transformer in the designed parameters, maintaining the pressure after finishing discharge to complete once welding and form weld seam. The present invention is suitable for common cold rolled low carbon steel plate and galvanized steel plate. The present invention has high welding efficiency and welded joint has high strength and toughness.

Description

technical field [0001] The invention relates to a method for resistance welding in the field of welding technology, in particular to a method for connecting a wide-band thin steel plate to a flattened capacitance energy storage welding method. Background technique [0002] In the production of automobile bodies and parts, in order to effectively use steel and save manufacturing costs, it is often necessary to splice thin steel plates. Since the spliced ​​workpieces are often required to be stamped and bent during production, the spliced The strength and toughness of the joint and the surface flatness of the joint are relatively high. At present, the resistance welding method of flattening seam welding is usually used to splice thin steel plates. Flatten seam welding is a lap joint method, and the welding is completed step by step through the rolling and electrification of the welding wheel. The welding productivity is low, and because this type of welding machine usually use...

AI Technical Summary

Problems solved by technology

Flat seam welding is a lap joint method, and the welding is completed step by step through the rolling and electrification of the welding wheel. The welding productivity is low, and because this type of welding machine usually uses AC power, the quality of the welded joint is difficult to guarantee

[0003] After searching the existing technical documents, it was found that Gao Jiasheng et al. wrote the article "Influence of ST44 Steel Flat Seam Welding Joint Microstructure and Strength" on "Baosteel Technology", 2000 (1). , and pointed out that the lack of fusion defect is the main reason for the low strength of the flattened seam welded joint. Increasing the welding current can reduce the size of the unfused joint, but the welding current should not be increased too much, which will increase the brittleness of the joint

Therefore, it is difficult to meet the requirements of joint strength and toughness at the same time for flat seam welding joints using AC power

At the same time, flat seam welding is often prone to welding defects at the beginning and end of the weld, and is especially not suitable for welding thin steel plates of the wide-band type (1-80mm in width) involved in the present invention.