无论在城市、工业企业的给水管网或输水管线的设计中,均需设置一定数量的法兰闸阀,其安装形式如图1所示。图中短管甲、乙均为铸铁管件,其承插口部分的接口材料为石棉水泥、水泥、膨胀水泥等,全部为刚性连接。故在阀门拆卸和更换时非常困难。 Whether in the design of the water supply network or the water supply pipeline of a city or an industrial enterprise, a certain number of flanged gate valves need to be installed. The installation form is shown in Figure 1. In the figure, the short tubes A and B are all cast iron pipe fittings. The interface materials of the socket part are asbestos cement, cement, and expansion cement, all of which are rigid connections. Therefore, it is very difficult to remove and replace the valve.