How to weld a ring weld that is 95 mm thick by forge welding?
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I would like to ask the experts: For a ring weld that is 95 mm thick (with an SA-266 cylinder wall of 95 mm thickness and a Q345R head of 80 mm thickness), there are no manholes, and it is not possible to weld or clean the back side; therefore welding can only be done on one side. How should this be done? Thank you.
Additional note: The challenge lies in the root welding; it must be fully penetrated, with 100% UT grade B compliance plus 20% RT grade AB II compliance
For the circumferential welds of 95mm thick materials, when welding can only be carried out from one side without root cleaning or back welding: 1. Grooving: To ensure weld quality, a V-shaped or U-shaped groove needs to be created between the cylinder and the head; the groove angle and size are determined according to the specific welding procedures. 2. Select the appropriate welding method: For materials with greater thickness, submerged arc automatic welding or gas shielded welding (such as MIG/MAG) is recommended. These methods can provide greater penetration and better weld quality. 3. Layered welding: Due to the large thickness of the material, it is recommended to use a multi-layer, multi-pass welding technique. Appropriate cleaning and inspection are carried out after welding each layer or several passes. 4. Preheating: Due to factors such as material and thickness, appropriate preheating can reduce welding stress and prevent crack formation. The preheating temperature is determined based on the material and thickness. 5. Post-treatment: After welding, heat treatment (such as annealing) may be required to eliminate residual stresses and improve the toughness of the welds as well as the stability of the overall structure. Before actual operation, consult the welding engineer in detail and follow the welding specifications; at the same time, carry out quality inspections during the welding process, including non-destructive testing of the welds