Problems with beveling thick-walled steel pipes
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How should grooves be made in 20G steel pipes? Should it be ground using a groove machine or a grinding wheel? Can I first use gas cutting to create a bevel and then grind it with a grinding wheel? Are there any regulations that can be referred to?
There are no specific requirements for carbon steel; the principles are as follows: 1, ease of use; 2, a smooth surface; 3, prevention of surface oxidation (if an oxide layer forms, it should be removed through machining or grinding)
In principle, regulations prohibit using flame cutting followed by grinding with an angle grinder, as this can cause adverse thermal effects on the pipes. However, for construction teams that do not have beveling machines on site, it is quite common to use a circular flame cutter to make 45-degree cuts and then repair the areas with an angle grinder.
I have another question: when welding 15CrMoG steel pipes, should it be heated first, then welded, and kept at a constant temperature after welding? Are there any standards I can refer to?
This post was last edited by qilupzh on 2011-7-12 at 14:54. Refer to JB 4709 for preheating before welding. According to both GB150 and JB4709, it is recommended to remove hydrogen immediately after welding. If post-weld heat treatment is carried out immediately after welding, the dehydrogenation treatment can be omitted.
A groove cutter or gas tungsten arc cutting machine; gas tungsten arc cutting is relatively simple to use.
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