DEVICE FOR CUTTING OFF PIPE LINE Russian patent published in 1995 - IPC

FIELD: pipe line engineering. SUBSTANCE: assembled valving unit is connected to a drive mounted in the outlet branch pipe. The unit is constructed as sealed lower and upper bottoms. The upper bottom is mounted in the inlet branch pipe. Telescopic members are arranged in pair and symmetrically with respect to the vertical axis of the central member and provided with arresting stops. The telescopic members are interposed between the lower and upper bottoms of the central member to define a space which is in communication with a pressure source through supplying passages provided in the upper bottom. Reverse springs are secured by their central part to the telescopic members. The ends of the springs are secured to adjacent members. The telescopic members and lower bottom are mounted inside the pipe line to define a ring space connected with a system for supplying sealing agent through the supplying passages of the upper bottom. EFFECT: enhanced reliability. 2 cl, 5 dwg