Spiral steel pipe submerged arc welding process instructions

Submerged arc automatic welding is a new welding method invented in 1940. The same thing as the previous manual welding is that it still uses slag protection, but this slag is not the coating of the welding rod, but a specially smelted flux. This flux system consists of a funnel that carries the flux through a pipe to the front of the welding site. The second difference is that welding rods are not used, but welding wires are used, because the welding wires can be fed continuously; with welding rods, after we burn a welding rod, one of the welding rod heads must be thrown away, and the operation must be stopped, the welding rod is changed and then welded again. After changing to welding wire, use the welding wire feeding device and the welding wire spool to continuously feed the welding wire. This welding method is that the continuously fed wire ignites the arc under the cover of the meltable granular flux, so that the welding wire, Part of the base metal, and flux melt and evaporate to form a cavity, and the arc burns stably in the cavity, so it is called submerged arc automatic welding. The arc is buried inside the cavity.

This method has three advantages:
The first advantage is that it is fully automated;
The second advantage is that it is welded under a submerged arc, so its heat exchange and protection performance is relatively strong, and the quality of the welded product is relatively high;
The third advantage is that since the arc is buried under the welding flux in automatic submerged arc welding, it can use large currents and the welding efficiency is relatively high;
The West-East Gas Pipeline Project is currently being carried out in our country, the pipeline is a kind of high-strength steel. This kind of pipe is pre-made into a section in the factory, and then it is taken to the construction site and welded in the field. This kind of pipe is made in the factory. The welding process is submerged arc welding. Now submerged arc welding has developed into double-wire submerged arc welding and multi-wire submerged arc welding, and the efficiency has been further improved.