Tapping valve

摘要

A tapping valve having a housing which can be electrically welded to a pipe and which includes a connection piece (2) with a drill (24) therein for drilling the pipe. The connection piece has an inner surface (34). The drill or a bushing (70) in which the drill can be moved axially by a threaded connection (74, 76; 80, 82) is provided with an external thread which engages the inner surface of the connection piece. Inner surface (34) is constructed such that it is initially cylindrical adjacent the external thread (32) and an inner thread can be formed in the inner surface (34) using the external thread (32) by rotating the drill (24) or the thread (70) in an axially forward direction (30). The tapping valve is easy to manufacture and yet offers a high degree of functional reliability.