How to avoid welding deformation in steel structure welding process?

In the steel structure welding process, welding deformation is difficult to completely avoid, but its impact can be minimized through a series of measures. Here are some ways to avoid welding distortion:

Optimize welding design: Arrange welds reasonably, minimize the number and cross-sectional area of welds, and avoid too dense or asymmetrical welds to reduce welding deformation and stress.

Rigid fixing method: Before welding or during the welding process, rigid fixing devices such as clamps and supports are used to fix the components to limit their deformation. This method can effectively reduce welding deformation, but attention should be paid to promptly removing the fixture after welding is completed to avoid causing additional stress to the components.

Anti-deformation method: Before welding, according to the predicted direction and size of welding deformation, deformation in the opposite direction is applied to the component to offset the deformation generated after welding. This method requires accurate deformation prediction in advance and taking corresponding measures to reverse deformation.

Adopt a reasonable assembly and welding sequence: For complex steel structures, the assembly and welding sequence should be reasonably arranged to try to allow the welds to shrink freely and reduce the accumulation of welding stress. At the same time, the principle of welding seams with large shrinkage first and then welding seams with small shrinkage should be followed.

Preheating and postheating: For components with larger thickness or greater rigidity, preheating is performed before welding to reduce the temperature gradient during welding and reduce the generation of welding stress. After welding is completed, post-heat treatment can also be performed to further eliminate welding stress.

Select the appropriate welding method and process parameters: Select the appropriate welding method and process parameters, such as welding current, voltage, welding speed, etc., based on the material, thickness and other factors of the steel. Reasonable welding parameters can reduce welding heat input and reduce welding deformation and stress.

It should be noted that despite the above measures, welding distortion may still exist to a certain extent. Therefore, after the welding is completed, quality inspection and necessary correction treatment are also required to ensure the quality and safety of the steel structure.