1. PrecisionCold welding machineWhat is the principle
Cold welding machine is often used in the field of precision welding repair, Therefore, it is also called precision cold welding machine. It is a welding equipment developed by applying the circuit principle similar to electric discharge machine.
The working principle of the precision cold welding machine is: using the charging capacitor, with the cycle of 10-3~10-1 seconds, the ultra-short time discharge of 10-6~10-5 seconds, the micro-electric instantaneous discharge produces The high thermal energy of the electrode material and the workpiece will be heated to 8000°C ~ 10000°C in an instant, and the molten metal in the plasma state transitions to the surface of the workpiece in a metallurgical manner, and is firmly fused with the original base material, so as to achieve welding. Effect.
The reason why the cold welding machine can achieve cold welding is because its discharge time is extremely short compared with the next discharge interval, the machine has enough relative stop time, and the heat will diffuse to the outside through the workpiece matrix , the processed part of the workpiece will not have heat accumulation.
Second, there are several types of common cold welding machines
The classification of cold welding machines is mainly based on the principle of cold welding. There are four main types of welding machines: energy storage resistance welding type, high energy arc welding type, pulse arc welding type and electric spark accumulation type:
1. Energy storage resistance welding type cold welding machine
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The electric energy stored in the capacitor is released to the connection point between the workpiece and the repair material in an instant (millisecond level), and the instantaneous large current through the contact resistance makes them rapidly heat up and weld together, achieving the repairing effect. Purpose. This cold welding machine is suitable for steel and other workpieces with high resistivity, but not suitable for metals such as copper and aluminum with good electrical conductivity.
2. High-energy arc welding cold welding machine
The electric energy stored in the capacitor is released in the form of pulsed arc in an instant (millisecond level). Between the tungsten electrode and the workpiece, the extremely high temperature arc rapidly melts the workpiece and the welding wire and welds them together to achieve welding. This cold welding machine can instantly weld the workpiece and welding wire together regardless of the size of the workpiece.
3. Pulse arc welding typeCold welding machine
Using the IGBT chopper module, the original continuous output welding The current is pulse-width modulated to form several square wave welding pulses as if chopped. Due to the limitation of the performance and rated power of the IGBT module, the pulse time of this type of welding machine is generally about several hundred milliseconds, and the pulse current is generally about 200A.
4. Electric spark deposition cold welding machine
At the moment when the welding material and the workpiece are in contact, a high-frequency, high-pulse high current is generated, resulting in The high thermal spark ion cluster, the tip of the welding material is ionized and deposited on the surface of the workpiece to form a repair layer.
