The surface quality of cast steel after welding repair should meet the following requirements:
① For non machined surfaces, the welding repair surface should be ensured to be flat, and the starting, ending, and both sides of the welding repair position should ensure a smooth transition with the base metal of the cast steel components;
② The defects that need to be inspected after welding repair shall be in accordance with the ISO 5817:2014 standard. The welding repair position shall not have defects such as cracks, pores, incomplete fusion, incomplete welding, incomplete welding, and pits;
③ The depth of weld repair undercut on non machined surfaces of important parts should not exceed 0.5mm, and other parts should not exceed 1mm;
④ Within every 100cm2 range of the weld surface, the number of pores with a diameter less than 2mm and a spacing greater than 6 times the diameter of the pores should not exceed 5;
⑤ The intersection of welds should be fully fused to ensure good molding. The intersection of welds should ensure a smooth transition.
When magnetic particle inspection is required according to the requirements of the inspection technology after defect welding repair treatment, the inspection range should cover the weld seam and the range of 100% welding repair width on both sides of the weld seam.
If cracks, incomplete fusion, incomplete penetration, slag inclusion, and defects beyond the specified limit are found at the position after welding repair, the defects should be thoroughly removed according to the above requirements before re welding. The maximum number of welding repairs at the same position is two. If the welding repairs at the same position exceed two, a review is required before implementation.
After welding and repairing defects in important parts of cast steel, records should be made or the welder’s steel seal should be stamped on appropriate parts.