Measures Of Welded Steel Pipe At Different Stages

No arcing or test current shall be made on the surface of the weld, and the surface of the weld shall not have any defects such as an arc abrasion. No cracks and other defects should be found in the weld seam, if the defects should be removed in time, the two ends of the locating welding path should be trimmed into a gentle slope shape. Argon arc welding, the use of argon gas purity should be above 99.9 ﹪, the protection of nitrogen purity should be greater than 99.5 ﹪, water content is less than 50mm/l.Welded Steel Pipe

When using argon arc welding to make the bottom process, tube inside can be filled with argon or nitrogen protection, the tube argon or nitrogen concentration should be greater than 99.9 ﹪ when the square can be applied welding, and gas flow should not be too large, to ensure the flow of gases can be, but also allow the use of flux-cored argon-arc welding wire, tube not inflatable body protection welding Welded Steel Pipe

There is a corrosion-resistant double-sided welding seam, and the side of the contact with the medium should be finally welded. Pipe diameter dn≥60mm butt weld, saddle-type angle butt joint using flux-cored wire or solid-core wire tube filled with argon or nitrogen protection manual tungsten Argon arc welding, other welding seam can be used argon arc welding bottom, manual arc welding cover surface, also allow the use of manual arc welding Bottom (design drawings or users require argon arc welding bottom outside), However, the welder must have the appropriate project with no mat, the welding process parameters are shown in the following table.Welded Steel Pipe The weld angle of the saddle and fillet welds shall not be less than the thickness of the branch pipe, and the welding level shall not be less than 2 layers and have a smooth transition to the geometrical shape of the base material. After welding, the weld slag and nearby splash material should be cleaned in time. Post-weld inspection: Each weld seam should be the vicinity of the requirements for welding welder code identification, but also indicate the pipeline line number, weld number and so on. The appearance inspection of welds shall be carried out according to the corresponding standards, and the size, shape and surface allowable defects shall conform to the corresponding regulations. Non-destructive testing of welded joints shall be carried out strictly according to corresponding piping standards.Welded Steel Pipe

The weld repair, the flaw eliminates uses the angle to grind the grinding wheel, until grinds out the flaw, after the appearance examination confirms the flaw-free, and repairs grinds into the gentle slope shape which is advantageous for the weld; for the linear defects such as crack, it is necessary to confirm the defect by repeated colouring inspection to be cleared before Welded Steel Pipe