1. Reduce the required power. It is possible to weld workpieces with larger cross-sectional area on a small-capacity welding machine, because when the welding machine's capacity is lacking, if the workpiece is not preheated to a certain temperature first, it will not be able to stimulate successive hydraulic processes. Preheating is the best way.
2. Decrease the cooling rate after welding. Let the cooling rate of the workpiece be slower, which can effectively prevent the quenching arrangement and cracks of the quenched steel joint during cooling.
3. Shorten the hydraulic time. Preheating can shorten the hydraulic time to reduce the hydraulic margin and save precious metal.
