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Foshan Shengbang Steel Structure Co., Ltd.

11 years experience in plant design and construction

Common choice of 1875 sets of steel structure buildings

National service hotline:

0757-81002668
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Key points of welding construction of steel structure

Hits：1727 Time：2017-4-13
　　1 welding process design
Determine the welding method, welding parameters and welding rod, welding wire, flux specifications, etc..
2 spot welding
In order to determine the accurate position of the parts, the spot welding should be carried out firstly. The length and thickness of spot welding shall be determined by calculation. The current should be 10%~15% higher than that of the formal welding, and the position of the spot welding should be avoided as far as possible, such as the stress concentration of the end and the edge of the component.
3 electrode baking
Electrode and powder cored wire before use must be baked according to the quality requirements, low hydrogen electrode after baking, should be placed in the incubator with the use of.
鋼結(jié)構(gòu)焊接
4 preheating before welding
Preheating can reduce the cooling rate of the heat affected zone, and prevent the formation of welding delayed crack. Preheat zone on both sides of the weld, the width of each side should be greater than 1.5 times the thickness of the weldment, and shall not be less than 100mm.
5 post weld heat treatment
The post weld heat treatment is mainly to deal with the weld to prevent the cold crack. The post heat treatment shall be carried out immediately after welding, and the holding time shall be determined according to the thickness of the plate according to the thickness of each 25mm 1h. Preheating and post heating can be carried out using a distributed flame gun.
6 welding sequence determination
The general began to expand from around the welding seam center; first welding shrinkage, after weld shrinkage; as symmetrical welding; weld intersection, weld longitudinal seam, after cooling to room temperature, then weld transverse weld; thick plate welding layer.