该产品顶盖是采用机关原理设计，带一个顶置螺纹口压板，方便打开和关闭并有良好的密封效果；另外正大滤床表面到布水头的距离，从而提高过滤阶段的布水效果，并避免在反冲洗时砂滤落入布水管内。本型砂缸特别设计的人孔，使砂缸在换砂过程中更方便，更高效。在过滤过程中，可通过本型砂缸设计的透视孔观察水质的过滤情况。

COMMERCIAL SAND FILTER

  New spiral cover system which aids the operations of opening and closing,The air purge is built into the cover which can be efficient to release the air from the filter.The distance between the upper part of the sand layer and the diffuser head(“freeboard”) has been increased to ensure grester distributiom of water in the filtration phase and avoid sand being split into he drain during backwash.Thespecially designed hole in the sand filter can make the sand exchanging process more convenient and efficient.In the filtering process.thefilering effect of water can be observed through the perspective hole which is designed in the sand filter.