Abschaltgerät für unter Druck stehende Flüssigkeitshandhabungs-Anlage

摘要

The circuit breaker comprises an internal valve (4) with a toroidal seal (8,28) placed in a housing (9,29) around the valve and a valve operating part (23,24). The housing is connected through a fluid channel (40,60) to a back pressure zone (41) formed downstream of the seal. During a transitory opening phase of the valve a preferential fluid flow circuit is brought about between the housing and the back pressure zone through the channel. By means of the back pressure exerted on the seal, there is no risk of its dislodging from its housing.