DEVICE FOR SIGNALLING THE PRESENCE OF PRESSURE INSIDE A PLANT, DUCT OR SPACE IN GENERAL

摘要

A device for signalling the presence of pressure inside a plant, duct or similar space comprises a first part (1) provided with means (51) for the hydraulic connection to the plant, duct or space under control, a second part (2) axially sliding inside said first part (1) and a central pin (3) fixed inside said second part (2). The central pin (3) is run along by an axial bore (52) for the hydraulic communication of the plant, duct or space under control with a chamber (200) arranged above said second part (2). At least one transversal bore (6) of said central pin (3) places said axial bore (52) of the pin (3) in communication with a first chamber (300a) of said second part (2) arranged above said first part (1). A second wider chamber (300b) is interposed between said first part (1) and said second part (2) and an annular cavity (300c) places said first chamber (300a) in communication with said second chamber (300b).