Valve for opening and closing a line system

A method for operating a valve comprising:

• providing a valve comprising:
• a valve body with a longitudinal axis and that forms a valve seat;
• a line system with a supply line for supplying a fluid to the valve seat and a discharge line for removing the fluid from the valve seat, wherein the fluid in the supply line stands under a supply pressure and in the discharge line under a working pressure;
• a closing element which cooperates with the valve seat for opening and closing the line system, wherein the closing element frees a throttle cross section between the valve seat and the closing element;
• a restoring element which supplies a restoring force onto the closing element, wherein the restoring force presses the closing element against the valve seat to close the line system;
• a pressure chamber in which the fluid stands under a closing pressure with which the fluid applies a closing force onto the closing element for closing the line system;
• and
• wherein the valve comprises a conduit via which the closing pressure can be lowered in the pressure chamber below the supply pressure as a function of the freed throttle cross section;
• wherein the conduit runs through the closing element and empties into the supply line, and wherein the conduit has a fluid communication with the pressure chamber;
• a bypass which comprises the conduit and an annular slot surrounding the closing element and emptying into the discharge line;
• an insertion element which forms, together with the closing element, at least a part of the conduit in an area of the throttle cross section;
• and
• freeing a throttle cross section between the valve seat and the closing element when the supply pressure (pV) exceeds a settable threshold value, and lowering the closing pressure (pS) in the pressure chamber below the supply pressure (pV) via the conduit.