本文通过对点焊机单管导通及单向磁化现象的分析，总结了导致上述现象的原因。以此为基础，研究了防止措施并设计了相应的电路。经过生产实验表明，这些措施效果显著，不仅提高了设备的可靠性和安全性，而且降低了成本，节约了能量，经济效益显著。 This article summarizes the reasons leading to the above phenomenon through the analysis of single tube conduction and unidirectional magnetization of spot welder. Based on this, the preventive measures were studied and the corresponding circuits were designed. After the production experiments show that these measures have significant effects, not only improve the reliability and safety of equipment, but also reduce costs, save energy, significant economic benefits.