Pressure relief valve with auxiliary loading device
AssigneeDresser Industries, Inc.
InventorYing-San Lai
Life of this patent
Estimating the term…
Abstract
A pressure relief valve including a valve member movable between open and closed positions to control fluid flow. A body member is provided which receives a piston operatively connected to the valve member for operating same. The piston defines a first chamber in the valve body extending above the piston and a second chamber extending below the piston. System fluid is introduced into the chambers and the differential fluid pressure in the chambers applies a loading force to the piston, and therefore to the valve member in its closed position. When the system pressure, and therefore the pressure in the chambers, exceeds a predetermined amount the pressure in one of the chambers is vented, causing the piston to move to an open position and permit opening movement of the valve member.
Claims13
A pressure relief valve assembly comprising:
- means defining a first chamber having an inlet for receiving fluid from an external source and an outlet for discharging said fluid;
- a valve member movable between an open and closed position in said chamber and in the path of said fluid flow between said inlet and said outlet so that said fluid urges said valve member to one of said positions;
- a stem extending from said valve member;
- means including a spring engaging said stem for normally biasing said valve member to the other of said positions so that said valve member moves to said one position in response to the fluid pressure exceeding a predetermined value;
- means defining a second chamber in a spaced relation to, and isolated from, said first chamber for receiving fluid from said source and for discharging said fluid;
- piston means disposed in said second chamber and responsive to a fluid pressure in said second chamber for engaging said stem for applying an additional force to said stem to force it, and therefore said valve member, to said other position;
- a spring disposed in said second chamber and urging said piston towards said stem;
- and
- means responsive to said predetermined pressure for releasing the fluid pressure in said second chamber to release said additional force and permit said valve member to move to said one position.
A pressure relief valve assembly comprising:
- means defining a first chamber having an inlet for receiving fluid from an external source and an outlet for discharging said fluid;
- a valve member movable between an open and closed position in said chamber and in the path of said fluid flow between said inlet and said outlet so that said fluid urges said valve member to one of said positions;
- a stem extending from said valve member;
- means including a spring engaging said stem for normally biasing said valve member to the other of said positions so that said valve member moves to said one position in response to the fluid pressure exceeding a predetermined value;
- means defining a second chamber in a spaced relation to, and isolated from, said first chamber for receiving fluid from said source and for discharging said fluid;
- piston means disposed in said second chamber and responsive to a fluid pressure in said second chamber for engaging said stem for applying an additional force to said stem to force it, and therefore said valve member, to said other position;
- means responsive to said predetermined pressure for releasing the fluid pressure in said second chamber to release said additional force and permit said valve member to move to said one position;
- and
- means responsive to the release of said additional force for shutting off the flow of said fluid into said second chamber.
Dependencies are inferred from the claim text.