MIG welding gun is divided into ten parts: 1. Contact nozzle 2. Gas protection nozzle 3. Insulating cylinder 4. Connecting rod 5. Ceramic shunt 6. Gun neck 7. Welding coaxial cable 8. Guide wire tube 9. , Trachea 10. Water pipe.When the above-mentioned current is exceeded, a water-cooled welding gun should be used. Among the semi-automatic welding guns, the gooseneck type is the most widely used. It is suitable for thin welding wires, flexible and convenient, and can be welded at any position. Pistol welding torch is suitable for thicker welding wire, because the current is relatively large, water cooling is often used. The basic structure of the automatic welding torch is the same as that of the semi-automatic welding torch, but its current is larger and the working time is longer. Generally, water is used for cooling.