Introduction of welding technology in steel structure bridge engineering

In addition to the requirements of the relevant specifications and standards of this technical requirement, the following provisions shall also be observed for the on-site welding of steel structure bridges.

(1) On-site installation and positioning, shall not be arbitrary on the steel beam components arc; No temporary accessories for construction shall be welded on steel beams; It is not allowed to use the steel beam as the ground of the general welding site; It is not allowed to knock on any part of the steel beam member. And must make explicit provision, as an operation discipline, strict implementation. -- In case of violation of the above provisions, on-site non-destructive inspection shall be carried out and corresponding treatment shall be carried out;

(2) Hoisting accessories should be cut off after the completion of the steel beam on site, generally divided into two cuts, the first cut is used as preheating, the second time is completely removed. After the lifting parts are cut, grinding wheel shall be used. The remaining height of lifting accessories after cutting should not exceed 20mm, 10mm~5mm is best, it is forbidden to damage members when cutting;

(3) The on-site welding should follow the principle of longitudinal welds from the middle of the span to both ends, transverse welds should be from the middle of the line to both sides of the welding sequence file, as far as possible to reduce welding deformation and weld constraint stress;

(4) On site welding should be equipped with windproof, rainproof measures and safety cover to prevent the impact of welding on the environment and traffic. All welding places should be covered. Welding is not allowed in rainy days. All exposed components are not allowed to be welded by C02 gas welding when C02 gas welding construction conditions cannot be used, and a wind shield should be added during welding. When C02 gas welding is used in the beam, safety measures of ventilation protection must be used;

(5) All welding holes and temporary process holes opened on the shell plate of the structure shall be closed after the completion of corresponding welding and installation.