Basic classification
According to the different electrodes, the argon arc welding machine is divided into two types: melting electrode argon arc welding machine and non-melting electrode argon arc welding machine.
Folding non-melting electrode argon arc welding
Non-melting electrode argon arc welding is the arc burning between the non-melting electrode (usually the tungsten electrode) and the workpiece, and an inert gas (usually argon gas) that does not react with the metal flows around the welding arc to form a protection The gas hood keeps the tungsten extreme tip, the arc, the molten pool, and the metal that is already at high temperature from contacting the air, which can prevent oxidation and absorb harmful gases. Thus, a dense welded joint is formed, and its mechanical properties are very good.
Folding melting pole argon arc welding
The welding wire is fed through the wire wheel, the contact tip is conductive, and an arc is generated between the base material and the welding wire, so that the welding wire and the base material are melted, and the inert gas argon is used to protect the arc and the molten metal for welding. The difference between it and argon tungsten arc welding: one is that the welding wire is used as an electrode, and it is continuously melted and filled into the molten pool, and the weld is formed after condensation; the other is the use of shielding gas, with the application of molten argon arc welding technology, protection Gas has developed from a single argon gas to a wide range of mixed gas applications, such as Ar 80%+CO220% rich argon protective gas. Usually the former is called MIG and the latter is called MAG. From the perspective of its operation mode, the most widely used are semi-automatic melting argon arc welding and argon-rich mixed gas shielded welding, followed by automatic melting argon arc welding.
Operating procedures
1. Argon arc welding must be operated by a dedicated person.
2. Check whether the equipment and tools are in good condition before work.
3. Check the welding power supply, whether the control system has a grounding wire, and add lubricating oil to the transmission part. The rotation must be normal, and the argon gas and water source must be unblocked. If there is a water leak, notify the repair immediately.
4. Check whether the welding gun is normal and whether the ground wire is reliable.
5. Check whether the high-frequency arc ignition system and welding system are normal, and whether the wires and cable joints are reliable. For automatic argon arc welding, also check whether the adjustment mechanism and the wire feeding mechanism are intact.
6. Select the polarity according to the material of the workpiece, and connect the welding circuit. The general material is DC positive connection, and the reverse connection or AC power supply is used for aluminum and aluminum alloy.
7. Check whether the welding groove is qualified. There should be no oil stains, rust, etc. on the surface of the groove. Oil and rust should be removed within 200mm on both sides of the weld.
8. Check the reliability of the molds used, and check the preheating equipment and temperature measuring instruments if the weldments need to be preheated.
9. The argon arc welding control button must not be far away from the arc, so that it can be turned off at any time in the event of a failure.
10. When using high-frequency arc ignition, you must always check for leakage.
11. If the equipment breaks down, the power should be cut off for maintenance, and the operator is not allowed to repair it by himself.
12. It is not allowed to be naked or exposed to other parts in the vicinity of the arc, and smoking or eating in the vicinity of the arc is not allowed to prevent ozone and smoke from being inhaled into the body.
13. Wear masks and gloves when grinding thorium tungsten electrodes, and follow the operating rules of the grinder. It is best to use cerium tungsten electrode (less radiation). The grinder must be equipped with an exhaust device.
14. Operators should wear static dust masks at all times. Minimize the time of high-frequency electric action during operation. Continuous work shall not exceed 6 hours.
15. The argon arc welding work site must be ventilated. Ventilation and detoxification equipment should be activated during work. When the ventilation device fails, it should stop working.
16. The argon cylinder is not allowed to be hit, and the stand must be placed in a vertical position, and it should be more than 3 meters away from the open flame.
17. When argon arc welding is performed inside the container, a special mask should be worn to reduce the inhalation of harmful fumes. Personnel supervision and cooperation should be arranged outside the container.
18. Thorium tungsten rods should be stored in lead boxes to avoid injury due to the radioactive dose exceeding safety regulations when a large number of thorium tungsten rods are gathered together.