DEVICE FOR SHUT-OFF OF PIPELINE INTERNAL SPACE Russian patent published in 2002 - IPC

FIELD: construction and repairs of pipelines. SUBSTANCE: metal framework is made in form of spool with dead flanges and provided with circular chamber whose external surface has friction cover plates hinged with spool by means of levers. Installed into needed place of pipelines is branch pipe carrying slide through which hole is drilled in pipe wall. Sealing device is introduced into pipeline with help of mechanism of introduction and withdrawal mounted on slide. Supplied inside device through hose is gas, for instance, nitrogen under pressure exceeding excessive pressure in pipeline to ensure sealing of pipeline shut-off. Longitudinal displacement of device is prevented by leverage which consists of friction cover plates, levers, spring and pins. Angle α between lever and device longitudinal axis is selected so that at full opening of device, lever system is wedged to prevent longitudinal motion of device. EFFECT: extended assortment of engineering means. 1 dwg