核测井仪器中的磁屏蔽研究

核测井仪器受套管剩磁的影响比较严重，常常用在探测器的周围缠绕多层坡莫合金带的方法进行磁屏蔽，由于缠绕的坡莫合金圆筒不能闭合，加上缠绕过程中坡莫合金带的形变造成材料本身磁导率的下降，传统的磁屏蔽方法的效果不好。本文介绍一种简单易行、磁屏蔽效果较好的方法，实验的结果说明用电工纯铁做探测器的外壳可以达到令人满意的效果。

On the Electromagnetic Shielding of Nuclear Logging Tool.

Nuclear logging tool is badly influenced by the remanence of the casing.The detector of the tool is often wrapped with bands of iron and nickel alloy for magnetic shielding .The effect of the traditional electromagnetic shielding (EMS) is not very good because the wrapped alloy band is not closed and due to its deformation its permeability becomes worse in the process of being wrapped. A new shielding design is discussed. The experiment result shows that satisfactory magnetic shielding can be achieved if the detector case is made of pure iron.