Preheating shall be carried out for carbon and lowalloy steel welding where required. Preheating temperature shall be kept uniform from the start to the end of welding.
在进行碳钢及低合金钢的焊接时应进行预热。预热温度在焊接开始到结束期间应保持均衡。
3
The quality of resistance spot welding of low carbon steel and high strength lowalloy steel is studied by looking into the dynamic voltage characteristics of the electrodes.