1. How to deal with the maximum welding current that can be achieved if the thickness of the workpiece exceeds the maximum welding current that the welder can reach when using GMAW and FCAW welding wire gas shielded welding (FCAW) welding steel (plate gold machining case cabinet) to make the workpiece.
The solution is to preheat the metal before welding. Propane, standard gas or acetylene welding torch is used to preheat the welding area of the workpiece, preheating temperature is 150~260 degrees, and then welded. The purpose of preheating the metal in the welding area is to prevent the weld area from being cooled too fast and not to cause cracks or non fusion.
2. If it is necessary to weld a thin metal cover on a thick steel tube (plate gold machining case cabinet) with a melting pole gas shielded welding or a cored wire gas shielded welding, if the welding current is not properly adjusted, it may lead to two cases: one is to prevent the thin metal from burning and reducing the welding current. The thin metal cover can be welded to the thick steel pipe, and the two is that the welding current will burn through the thin metal cover. How should we deal with it at this time?
There are two main solutions.
First, adjust the welding current to avoid burning the thin metal cover, and preheat the thick steel pipe with the torch, then weld the two metal structure with the thin plate welding process.
Second, adjust the welding current to suit the welding of thick steel tube (sheet metal processing cabinet). During welding, the retention time of the welding arc on the thick steel pipe is 90%, and the residence time on the thin metal cover is reduced. It should be pointed out that only when we master this technology can we get a good welding joint.
3. When a thin-walled tube or rectangular thin wall pipe is welded to a thick plate, the electrode is easy to burn through the thin-walled tube. In addition to the two solutions mentioned above, are there any other solutions?
Yes, a heat sink is used during welding. If a solid circular rod is inserted into a thin-walled tube or a solid rectangular bar is inserted into a rectangular tube, the solid rod will take away the heat of the thin-walled workpiece and prevent the burn through. In general, solid rods or rectangular rods are tightly installed in most of the hollow or rectangular tubes. When welding, the weld should be kept away from the end of the pipe. The end of the pipe is the most vulnerable area to burn through. Avoid burning through with a built-in heat sink.
标签:   钣金加工 钣金件加工