在水井建设施工中,为保证管井能正常出水,除必须严格按成井工艺要求施工外,还应当正确设计管井的结构。过滤器是地下水进入井内的通道,在松散地层中,过滤器设计是管井姑构设计最关键的环节。因为缠丝过滤器制作简便,经久耐用,使用效果好,尤其第四纪松散沉积物颗粒不太小的含水层中更有良好的效果,所以被广泛采用。但在缠丝过滤器的制作和使用中还存在不科学、不经济的现象,现对其中存在的两种主要问题作一分析。 一、缠丝间距过小 在理论上,通常是以含水层砂砾的级配情况来确定(?)填拉料的粒径,再根据粒料的粒径来确定过滤器的缠丝间距。具体做法是:通过对含水层土样进行筛分,然后经过计算确定填料的粒径,进而确定缠丝闻距,比较繁琐。因此在实际凿井生产中基本上不采用这种方法,而是简单地将间距确定为1.5毫米左右,并且现 In the well construction and construction, in order to ensure that the tube well can produce water normally, it is necessary to correctly design the structure of the well tube in addition to the construction strictly required by the well completion technology. The filter is the passageway through which the groundwater enters the well. In the loose formation, the filter design is the most critical aspect of the auroral design. It is widely used because the silk filter has the advantages of simple and convenient manufacture, durability and good use effect, especially in the aquifer where the quaternary loose sediment particles are not too small. However, there are still unscientific and uneconomical phenomena in the manufacture and use of the filament filter, and the two main problems now exist are analyzed. First, the winding wire spacing is too small In theory, the grading of aquifer grit is usually used to determine the particle size of the filler, and then determine the filter wire wrap spacing based on the particle size of the aggregate. Specific approach is: through the aquifer soil samples were screened, and then calculated to determine the particle size of the filler, and then determine the smell around the wire, more complicated. Therefore, this method is basically not used in actual shaft production, but the spacing is simply determined to be about 1.5 millimeters, and now