The treatment method of deformation problem in steel structure machining and forming

The cause of the steel structure deformation 

1, The deformation in the processing of complex steel structures mainly includes hot deformation, cold deformation or the failure to assemble the interrelated components into a whole.

2, Thermal deformation is usually caused by improper welding process; Cold deformation is caused by large volume and poor rigidity; The interrelated components cannot be assembled into a whole, which is related to incorrect lofting and marking, incorrect assembly sequence or deformation.

Method of operation for reducing thermal deformation of welding steel structure

1, Fixture fixation method: The combination welding parts are clamped with a very rigid fixture, deformation is controlled by force, and then welding is carried out. This method is called the fixture fixation method.

During welding, the expansion force and contraction force generated inside the welding parts are limited by the clamping force, which can obviously reduce the deformation.

However, this method is not suitable for the components that require less internal stress due to the large internal stress in the welded parts.

2, Reverse deformation method: before welding, the members should be judged according to the condition of the welded metal members.

When cooling after welding, the direction of deformation and shrinkage occurs, the welding parts should be bent or tilted in the opposite direction in advance. After welding, due to its own shrinkage deformation, it just returns to the predetermined shape and position. It can prevent welding deformation and reduce welding stress.

3, The use of positioning control method: members before welding, with many welding points, will be welding parts or around positioning, can also be pressed on both sides of the welding weight, this method is called the positioning control method.

4, Welding sequence method: Correct arrangement of the welding sequence is an effective method to prevent welding deformation.

The law of welding deformation is that the deformation caused by the first welding seam is the largest, and the deformation caused by each welding seam generally cannot offset each other. The final deformation direction is consistent with the deformation caused by the first welding seam.