针对磁粉检测过程中, 采用线圈纵向磁化受零件长径比影响较大的难题, 对磁粉检测标准中规定的规范公式, 在不同长径比下分别做了计算。统计得出, 当零件长径比值在2~15范围内时, 由规范公式得出的计算值有效; 当长径比值<2时, 应在零件两端连接与零件材质相同或相近的延长块, 使长径比值>2后再做磁化。

Aiming at the problem that the length-diameter(L/D) ratio has a greater effect on coil longitudinal magnetization in the magnetic particle testing, the formula specified in the magnetic particle testing standard was calculated with different L/D value, the statistical result showed that, while the L/D value was in the range of 2~15, the calculated result was effective. On the other hand, while the value was less than 2, it was essential to use the extending blocks of same or similar material to connect the terminal of component to make the L/D value being greater than 2, and only of ter that could it be magnetized.