A discharge valve, for regulating a pressurised fluid discharged from a pressurised vessel into a pipe installation, comprising a body with a plurality of hollow chambers connected through passageways of different cross-sections, said body including: - a first pressurised chamber and a second pressurised chamber, said first pressurised chamber is connected to a pressurised fluid (Po) vessel and said second chamber is connected to a pressure source, - a discharge outlet connected to said pipe installation, - a movable mechanism configured to perform a lineal movement along a central axis of the valve body between a closed position and an open position, in response to said pressure source, wherein in said open position said pressurised fluid is transferred from the first chamber to a main chamber, characterised in that the discharge valve further comprises a cylindrical sleeve with an annular inner wall, coaxial to said movable mechanism, resting on top of and surrounding a pre-set spring which is configured to perform an opposing force against said annular inner wall and in that the pressurised fluid is transferred from said main chamber to an outlet chamber and to the discharge outlet through transversal feeding passageways of said main chamber aligned with orifices of the cylindrical sleeve; wherein the outlet chamber is also connected through passageway to a regulating chamber, which allows the pressurised fluid to exert a pressure on an annular upper surface opposite said inner wall of the cylindrical sleeve, to counteract said opposing force of the spring; and wherein the regulating chamber is also in communication with the discharge outlet through at least one discharge passageway, so that a Venturi effect is created at an end of said discharge passageway by the pressurised fluid (Po) exiting the discharge outlet; whereby changes in the pressure value of the regulating chamber occur and provide a dynamic lineal bidirectional movement of the cylindrical sleeve to regulate the pressure of the pressurised fluid outputted (Pf) into the pipe installation, as a function of the axial position within the valve body of the orifices regarding transversal feeding passageways. - a first pressurised chamber and a second pressurised chamber, said first pressurised chamber is connected to a pressurised fluid (Po) vessel and said second chamber is connected to a pressure source, - a discharge outlet connected to said pipe installation, - a movable mechanism configured to perform a lineal movement along a central axis of the valve body between a closed position and an open position, in response to said pressure source, wherein in said open position said pressurised fluid is transferred from the first chamber to a main chamber, wherein the outlet chamber is also connected through passageway to a regulating chamber, which allows the pressurised fluid to exert a pressure on an annular upper surface opposite said inner wall of the cylindrical sleeve, to counteract said opposing force of the spring; and wherein the regulating chamber is also in communication with the discharge outlet through at least one discharge passageway, so that a Venturi effect is created at an end of said discharge passageway by the pressurised fluid (Po) exiting the discharge outlet;