Apparatus for permitting access to the interior of a subterranean fluid-carrying pipe by way of an excavation which has uncovered the wall of the pipe

摘要

Apparatus for permitting access to the interior of a fluid-carrying pipe, the apparatus comprising a valve assembly adapted to permit a hole to be drilled in the wall of the pipe or an item to be introduced into or removed from the pipe by way of a pre-existing hole in the wall of the pipe without fluid escaping from the assembly and a member which has a first end connected to the valve assembly and a second end for engaging that part of the wall of the pipe lying opposite the valve assembly, the member being adapted to be lowered into the excavation and then engaged with the wall of the pipe in such a manner that the valve assembly can be clamped to the wall of the pipe.