Abstract: A quick coupling device for a fluid-tight, especially temporary connection to a pipe nipple (1) or the like, comprising a cylindrical casing (5,14), which is mechanically connectable to the pipe nipple, and a coupling piston (16,18), which is displaceably disposed in the cylindrical casing and which is permanently connectable to a pressurized fluid conduit (4) and has a through-going opening (27) for the passage of pressurized fluid to said pipe nipple, the coupling piston being displaceable, by the action of a separate actuating fluid (via 30), into sealing (21) contact with the end surface (22) of the pipe nipple (1).

Abstract: A quick coupling device for fluid tight, especially temporary connection to a threaded pipe nipple (2) or the like, e.g. for use in tightness tests or leak detection. The device comprises two portions which are axially movable relative to each other, namely a cylindrical casing (3) and a piston (4) displaceably mounted therein. The casing and/or the piston are adapted (5) for permanent connection to a pressurized fluid conduit, and the piston has a through opening (9) permitting the flow of pressurized fluid to the pipe nipple (2). According to the invention, one (e.g. the piston (4) of the axially movable portions is provided with a thread dimensioned to be screwed into engagement with the thread of the pipe nipple (2), whereas the other portion (e.g.