1, design measures. Minimize the number and size of welds, and reduce welding stress while reducing deformation. Prevent the weld from being too concentrated, so as to avoid the superposition of welding stress peaks. For containers with higher requirements, the plug-in type should be changed to the flanging type.

2. Technical measures. Using less welding line energy can reduce the range of weld thermoplastic deformation, thus reducing welding stress. Arrange the assembly and welding sequence reasonably, so that the weld can shrink freely and reduce the residual stress in welding. When welding high strength steel, covered electrode with good plasticity should be selected. Adopt integral preheating. Reduce the hydrogen content in the weld, and carry out hydrogen elimination treatment after welding to reduce hydrogen-induced concentrated stress.

3. Methods to prevent and reduce welding stress: preheating, heating "stress reduction zone", reasonably selecting welding process parameters and tapping method. Methods to prevent and reduce welding deformation: anti-deformation method, determination of reasonable assembly welding process, selection of reasonable welding sequence, rigid fixation method and heat dissipation method.

Measures to prevent welding deformation;

Reasonable welding structure design, reasonable assembly process measures, reserved shrinkage allowance method, deformation prevention method and rigid fixation method are adopted. Reasonable selection of assembly procedure. Adopt reasonable welding process measures and reasonable welding methods. Try to use gas shielded welding and other welding methods with concentrated heat sources. Arc welding is not suitable, especially gas welding.

Reasonable welding specification. Try to use small specifications to reduce welding line energy. Reasonable welding sequence and direction. Carry out interlayer hammering.