The release of large diameter draw-off and control valves

摘要

A patented new technology to release in situ stuck water valves without interrupting control or flow processes is explained. The technology can be applied to any type and size of valve, gate, butterfly, ball plug check etc. The release of both a 48-inch and 21-inch diameter gate valves and two 48-inch diameter butterfly valves at two raw water storage reservoirs belonging to Anglian Water Services in December 2001 is described.