The difficulties and characteristics of steel box girder assembly welding include:
1, Large amount of welding work;
2, the asymmetry of steel structure can easily lead to welding distortion.
3, It is difficult to control the geometric dimension of welding. Therefore, in order to realize the accurate control of the annular weld, the longitudinal seam of the floor and the top of the steel beam, the technology of the submerged arc automatic welding machine is first adopted, and the carbon dioxide MAG welding and the MMA welding with high flexibility are used.
The MZ-1250, NB500 and ZX5-630 series of FONDOF welding machines made by Guangzhou EACO electrical equipment Co., Ltd. have been successfully applied to the ring mouth welding, vertical welding and 37 degree slanting floor seam forming for the steel box girder of Hong Kong-Zhuhai-Macao Bridge. The high requirements for the technical performance of the welding equipment are in the forefront of world welding level at present, which means "the longest trans sea bridge in the world" - the Hong Kong-Zhuhai-Macao Bridge will become a landmark of China from a large bridge-construction country to a power bridge–construction country.