How should iron castings be welded
During the production process of iron castings, if some simple casting defects occur, welding can generally be used to repair and solve them. So, how should iron castings be welded? What are the specific steps?
1. According to the design drawing, product batch number, production date, etc. of the cast iron, combined with the specific damage situation of the cast iron, find the best welding position;
2. Draw corresponding welding allowance for different casting defects on the welding drawings of iron castings;
3. Before welding, clean the residual stains on the surface of the iron castings to ensure that the surface of the iron castings is clean;
4. Preheat the surroundings of the welding site to achieve a temperature of 200-250 ℃, thereby reducing the overall temperature difference between the welding site and the cast iron;
5. Before welding, select suitable welding rods according to the specific damage situation of the cast iron, and preheat and bake the welding rods at 150 ℃ for about two hours before welding;
6. During welding, place the cast iron parts obliquely to make the welding on an uphill slope;
7. If both sides of the groove are relatively small, rapid direct welding can be adopted. A small swing can be made in the middle of the weld to fully fill the weld;
8. If the cast iron is thicker, multi-layer and multi-pass welding can be used, but attention should be paid to selecting a reasonable welding sequence to minimize the stress generated by welding.