国家在 2 0 0 2年对消防管道连接强制采用沟槽式连接并推广应用的时候 ,其特有的安装简捷方便、连接可靠等优点得到了充分体现。但出现了管道与阀门连接的问题 (在每个阀门连接处 ,必须安装两只法兰连接器 ) ,不能完全体现出沟槽式连接的优点。例如 ,DN10 0闸阀增加两只法兰连 When the state forced the use of trench connection to fire-fighting pipeline connection in 2002 and promoted its application, its unique advantages such as simple and convenient installation, reliable connection and others were fully demonstrated. However, there was a problem of pipe-to-valve connection (two flange connectors must be installed at each valve connection), which did not fully reflect the advantages of the grooved connection. For example, DN10 0 gate valve with two Flanges