摘要 |
<p>A method and a device for interrupting or reducing a media flow through a tubular pipe, involving removal of two opposed circumferential wall portions of the tubular pipe by means of two mainly parallel pistons, thereafter moving a third piston mainly mutually perpendicularly to the direction of travel for the pistons parallel piston and the length axis of the tubular pipe to a position mainly extending through the parallel pistons, the tubular pipe and the opposed openings of same, the third piston means being arranged with expanding devices, which, after completed movement of the third piston, are expanded to reduce, or interrupt, the internal cross-sectional area of the tubular pipe.</p> |