Elimination of residual stress in tube sheet welding

Heat Treatment Method: After tube sheet welding, overall or local heat treatment is applied, heating to 550-650℃ and maintaining the temperature, followed by slow cooling to eliminate 60%-80% of residual stress. This method effectively reduces the risk of tube sheet deformation, but temperature control is necessary to avoid material property degradation. It is suitable for high-pressure applications such as chemical equipment.

Mechanical Vibration Method: Vibration equipment is used to induce resonance in the tube sheet, promoting the redistribution of residual stress. This method is simple to operate and low in cost, eliminating approximately 30%-50% of the stress, but its effect is weaker than heat treatment. It is often used in weight-sensitive fields such as aerospace.

Process Optimization: During the design phase, reduce weld concentration, adopt a symmetrical welding sequence, and reduce the local rigidity of the tube sheet. Combining this with hammering or pre-deformation techniques further releases stress, improves assembly accuracy, and ensures the long-term stable operation of the equipment.