AWWA ACE65207

This paper presents the development of a new method of water cut-off, addresses shortcomings of previously developed counter-measures, and minimizes cut-off area and time. The main features and considerations include: the ability to insert and unfold its wing-like device to block the water flow; can be applied to large-diameter pipes and to pipes of various diameters with one device; minimizes working area (2-4m); simple and easy to insert into pipes; applicable in high pressure (up to 20 kg/cm²) pipes; and, minimum water cut-off time (less than 2 hours). Case studies of two existing facilities are profiled, and future plans are listed. Includes 4 references, tables, figures.