Safety management of spiral steel pipeTo solve the problem of misalignment in the alignment of spiral steel pipe nozzles, the following preventive measures should be taken in the quality management control:1. Try to use the internal alignment device.2. Do engineering measurement and trimming work du
Causes of slag inclusion in longitudinally welded steel pipes and cutting methodsSlag inclusions in longitudinally welded steel pipes are slag remaining inside the weld. From theoretical analysis, the main reasons for slag inclusion in submerged arc automatic welding are as follows: ①There are more
Causes of trachoma in the weld of spiral seam submerged arc welded steel pipeThe spiral steel pipe is made by bending the steel strip in the spiral direction through the coiling machine, and then through the double-sided submerged arc welding of the capacitor. In the production process of spiral ste
Pre-treatment and use of straight seam steel pipePre-treatment of straight seam steel pipe:Non-destructive inspection of the inside of the weld. Because the pipeline belongs to the extra-large steel pipe in the water supply project, especially the steel pipe with a thickness of t=30mm is used as a p
1. Water welding with pressureThis method is suitable when the pipeline leaks, the pipe itself is in good condition without serious rust and other defects, and the pressure in the pipe is small, so it can be directly welded.2. Self-made pipe clamp plugging methodThis method is suitable for methods s
1 Judging from the surface, that is, in visual inspection. The visual inspection of welded joints is a simple procedure with a wide variety of inspection methods. It is an important part of finished product inspection, mainly to find welding surface defects and dimensional deviations. Generally, the
1. Welding processIn the welding process, the welding method of the spiral steel pipe and the longitudinal welded pipe is the same, but the longitudinal welded pipe inevitably has many T-shaped welds, so the probability of welding defects is greatly increased, and the welding residual stress at the
The appearance of the spiral steel pipe is not treated, which is beneficial to improve its service life.1. Use a wire brush, sandpaper, and other tools to polish the surface of the anticorrosive spiral pipe, which can remove loose oxide scale, rust, welding slag, etc.2. Use solvents and emulsions to