Resistance welding machine, the efficiency of the TIG welding than traditional 3 to 5 times. After often due to lack of penetration of the root and crater and other pit defects instead of using TIG welding end MIG welding filling and capping process, although the improved welding process basically solves the root of the problem of incomplete penetration, reduces the welding efficiency, increased investment in equipment while also complicating operational procedures. Recently, the pot, pot imported from abroad hot wire TIG automatic pipe machine. The principle of hot wire TIG welding is that the filler wire is supplied by a separate constant voltage AC power supply before it is fed into the weld puddle.
Resistance heating to 650 ~ 800 ℃ high temperature, which greatly accelerated the wire melting rate, the deposition rate close to the same diameter MTG welding deposition rate. In addition, the TIG method of good back cover features to ensure the back cover of the weld quality, therefore, hot wire TIG welding is the preferred choice of a small diameter wall thickness butt welding method. However, this should not be a complete denial of the feasibility of pulsed MIG welding in the application of small diameter wall thickness pipe joints. In a large number of experiments, it has been found that in the MIG welded butt joints of thick-walled tubes, more than 90% of the root end penetration is located in the super-arc section, and the crater droop causes overheating due to the metal heat accumulation in the molten pool during continuous multi-layer welding. If the welding power arc power for precise control, you can completely eliminate the formation of the above defects. However, due to the introduction of the MIG welding machine automatic welding machine original wife of the thyristor pulse power supply, can not achieve the arc power of program control, such as switching to the most advanced all-digital control of inverter pulse welding power supply or waveform control pulse welding power supply (computer software control small), you can easily according to the welding process requirements, the power of the welding arc for precise control to ensure the welding quality joints.
