摘要 |
<p>Valve units are disclosed, for connection in a water supply pipe line buried underground, and which comprise a base part (1) for conbnection with the upstream and downstream branches (22,20) of the pipe line at substantially the same level as the latter and a sleeve (24) which extends upwardly from the base part to an access opening at ground level, the sleeve defining an inspection and access shaft for the valve units and for metering devices (5) mounted on the valve units. The valve units include stop valves (2) operable manually by appropriate tools (8), and one way valves (4), the stop valve, one way valve and metering device in each unit being connected in series between the upstream and downstream branch from the point of view of fluid flow.</p> |