天津地质处研制成功的贴砾滤水管,是一种先进的水井过滤器,在生产井中使用具有很多优越性,但应用于勘探井中尚有不足之处,因为贴砾层贴死在花管上,增大了管材外径和重量,它将对井管的起拨增加困难。为了克服提拔井管难的缺点,我们将贴砾滤水管,改为活套式砾石滤水管(以下简称砾石管)。它与花管不是组成牢固的整体,而是相互可以分离的两部分,只是在使用时套在钢质花管上一块使用,它的制作工艺和贴砾管大同小异。现将制作工艺和使用情况介绍如下: The geology filter pipe developed by the Tianjin Geological Department is an advanced water well filter. It has many advantages in production wells, but it is still used in exploration wells because the gravel layer sticks to the flower pipes. It increases the outside diameter and weight of the pipe, which will make it difficult to raise the well pipe. In order to overcome the shortcomings of lifting the well pipe, we changed the gravel filter pipe to a loose-type gravel filter pipe (hereinafter referred to as a gravel pipe). It and the floral tube are not composed of a solid whole, but are two parts that can be separated from each other. They are used only when they are put on a steel flower tube for use. Its manufacturing process is similar to that of a gravel tube. The production process and usage are described as follows: