How to improve the quality of spot welding of galvanized steel plate by intermediate frequency inverter spot welding machine?

How to improve the quality of spot welding of galvanized steel plate by intermediate frequency inverter spot welding machine? Is there a way? I believe many friends are interested. The following is a small series of science and technology to explain to you.

1, select and strictly control the welding process parameters. The evaluation of spot welding quality of galvanized steel sheet refers to the strength of a single solder joint, the level of corrosion resistance, and more importantly, the pass rate of solder joints under large-scale production conditions. In actual production, there are many factors that affect the quality of welding, such as the fluctuation of network voltage, shunt, electrode wear, and assembly quality.

Because the range of welding parameters of galvanized steel sheet is inherently small, it needs to be strictly controlled, and it needs to be adjusted when the plate thickness changes.

2. Use reasonable electrode materials, electrode shapes and sizes, and timely repair or replacement of electrodes. Good cooling of electrodes is very important to ensure welding quality.

3. Use multi-pulse or Slope current method to weld galvanized steel sheets. One is to increase the preheating and post-heating current, and the other is to increase the ramp-up and ramp-down current. By using high-speed photography to photograph the formation process of weld nugget, the effect of changing current is studied. We believe that: 1) the change of current can promote the formation of weld nugget; 2) the change of current before welding contributes to the uniform formation of weld nugget; 3) The change of current after welding helps to restrain the nugget and prevent spatter; 4) The simultaneous use of current after welding and before welding can combine the advantages of both. This current change has been used for welding production of galvanized steel sheets.

4, increase the control function, improve the control accuracy, real-time monitoring of welding parameters. The control system of the new welding machine used in the foreign automobile factory is based on the microprocessor, and the two basic characteristics of these new control methods are the primary voltage compensation and the current step function. The primary voltage can be compensated to ensure that the welding current changes within 1% of the set value, and the step function can automatically compensate for the current density drop caused by electrode wear and maintain a suitable welding current density. A new generation of welding machine control system may be the use of a powerful microprocessor, through continuous measurement of welding parameters and weld nugget formation process to monitor each solder joint.