Spiral steel pipe (SSAW pipe) is a welded pipe with spiral weld seam, which is made of strip steel coil as raw material, extruded at regular temperature, and welded by automatic double-wire double-sided submerged arc welding process. When there are defects such as broken arc, burn through, slag inclusion, pores, cracks and other defects in the weld of the spiral steel pipe, the problem weld of the spiral steel pipe needs to be repaired, which is called repair welding.
Repair welding requirements
1. Welders need to wear protective measures before repair welding, such as welding helmets, gloves, overalls, insulating shoes, etc.
2. When repairing the welding of the spiral steel pipe, the electric welding needs to start the arc first, and the electric welding arc should be careful not to strike the arc on the base material of the spiral steel pipe, which is stipulated in the standard. When repairing welding, the welder can first take a small iron plate and put it by his side to start the arc and adjust the current.
3. The defects of the spiral steel pipe should be completely removed
4. Multiple weld defects with an interval of less than 100mm in the spiral steel pipe should be repaired as a continuous single weld. A single weld of the spiral steel pipe shall be repaired in at least two layers/passes. For short-distance spiral steel pipe repair welding, the minimum length is 50mm. For example, if the length of the weld defect is 30mm, the length of the weld defect should be repaired according to 50mm.
5. The length of the repair welding seam of each steel pipe of the spiral steel pipe The total length of the weld seam should be less than or equal to 5% of the total length of the weld seam of the spiral steel pipe.
6. The number of repair welding of spiral steel pipe shall not exceed two times.
7. After the repair welding of the spiral steel pipe is completed, the spatter and welding flow on both sides of the repair welding seam should be cleared, and the lap between the repair welding seam and the original welding bead should be ground and smoothed.
8. After the repair welding of the spinning steel pipe, the flaw detection, water pressure, appearance and size inspection must be re-inspected.
Repair welding requirements
1. Welders need to wear protective measures before repair welding, such as welding helmets, gloves, overalls, insulating shoes, etc.
2. When repairing the welding of the spiral steel pipe, the electric welding needs to start the arc first, and the electric welding arc should be careful not to strike the arc on the base material of the spiral steel pipe, which is stipulated in the standard. When repairing welding, the welder can first take a small iron plate and put it by his side to start the arc and adjust the current.
3. The defects of the spiral steel pipe should be completely removed
4. Multiple weld defects with an interval of less than 100mm in the spiral steel pipe should be repaired as a continuous single weld. A single weld of the spiral steel pipe shall be repaired in at least two layers/passes. For short-distance spiral steel pipe repair welding, the minimum length is 50mm. For example, if the length of the weld defect is 30mm, the length of the weld defect should be repaired according to 50mm.
5. The length of the repair welding seam of each steel pipe of the spiral steel pipe The total length of the weld seam should be less than or equal to 5% of the total length of the weld seam of the spiral steel pipe.
6. The number of repair welding of spiral steel pipe shall not exceed two times.
7. After the repair welding of the spiral steel pipe is completed, the spatter and welding flow on both sides of the repair welding seam should be cleared, and the lap between the repair welding seam and the original welding bead should be ground and smoothed.
8. After the repair welding of the spinning steel pipe, the flaw detection, water pressure, appearance and size inspection must be re-inspected.
