Overpressure relief control system
First Claim
1. A method of relieving an overpressure condition within a pressurized system having a pressure passage to vent pressurized fluid therefrom comprising the steps of:
- (a) providing at least two relief passages for flowing a pressurized fluid to a safe discharge location;
(b) interconnecting said relief passages with said pressure passage by means of a valve normally in a first position to provide full flow communication between said pressure passage and a first of said relief passages, said valve including motor means to move said valve between said first position and a second position providing full flow communication between said pressure passage and a second relief passage;
(c) providing each relief passage with an overpressure relief device having a respective overpressure rating, said relief device in the first relief passage being a rupture disc;
(d) sensing the integrity of said rupture disc;
(e) sensing the pressure within said pressure passage; and
(f) upon sensing the rupture of said rupture disc and upon the pressure in said pressure passage decreasing to a selected first fraction of the overpressure rating of the relief device in said second relief passage, controlling said motor means to place said valve in said second position.
1 Assignment
0 Petitions
Accused Products
Abstract
A control system for an overpressure relief arrangement includes a valve providing selective communication between a pressure passage connected to a pressure vessel and a pair of relief passages, each relief passage having an overpressure relief device therein; sensors for monitoring the pressure in the pressure passage, the status of the relief devices, and the position of the valve; an actuator to move the valve; and a computer to make decisions concerning the placement of the valve based upon the data derived from the sensors. The valve normally provides communication between the pressure passage and first relief passage preferably having a rupture disc therein. Upon rupture of the disc, the system pressure is monitored until it is safe to switch to the second relief passage without overpressuring the relief device therein. If the pressure should increase to the overpressure level within a selected period, the valve is switched back to the first relief passage to exhaust the pressure to a safe level; and the valve is switched back to the second relief passage when sufficient pressurized fluid has been exhausted.
26 Citations
14 Claims
-
1. A method of relieving an overpressure condition within a pressurized system having a pressure passage to vent pressurized fluid therefrom comprising the steps of:
-
(a) providing at least two relief passages for flowing a pressurized fluid to a safe discharge location; (b) interconnecting said relief passages with said pressure passage by means of a valve normally in a first position to provide full flow communication between said pressure passage and a first of said relief passages, said valve including motor means to move said valve between said first position and a second position providing full flow communication between said pressure passage and a second relief passage; (c) providing each relief passage with an overpressure relief device having a respective overpressure rating, said relief device in the first relief passage being a rupture disc; (d) sensing the integrity of said rupture disc; (e) sensing the pressure within said pressure passage; and (f) upon sensing the rupture of said rupture disc and upon the pressure in said pressure passage decreasing to a selected first fraction of the overpressure rating of the relief device in said second relief passage, controlling said motor means to place said valve in said second position. - View Dependent Claims (3, 4, 5, 6)
-
-
2. In a method of controlling a valve in an overpressure relief arrangement, said valve being normally placed in a first position by motor means to provide full flow communication between a pressure passage and a first of at least two relief passages, each of said relief passages having an overpressure relief device therein, each relief device having a respective overpressure rating, the relief device in at least the first relief passage being a rupture disc, said motor means being operable to place said valve to provide flow communication between said pressure passage and the other of said relief passages, the improvement comprising the steps of:
-
(a) sensing the integrity of said rupture disc; (b) sensing the pressure within said pressure passage; and (c) upon sensing the rupture of said rupture disc and upon the pressure in said pressure passage decreasing to a selected first fraction of an overpressure rating of the relief device in a second relief passage, controlling said motor means to place said valve in a second position providing full flow communication between said pressure passage and said second relief passage.
-
-
7. In combination:
-
(a) a valve assembly comprising a valve housing, a valve, a pressure passage communicating with said valve and two relief passages communicating with said valve, said assembly including motor means to position said valve to provide selective flow communication between said pressure passage and said relief passages, said valve normally being placed in a first position to provide full flow communication between said pressure passage and a first relief passage, each of said relief passages having an overpressure relief device associated therewith, a first relief device associated with said first relief passage being a rupture disc; and (b) a control system to control the position of said valve, said control system comprising; (1) transducer means providing a pressure signal indicative of the pressure within said pressure passage; (2) relief indicator means cooperating with said first relief device to generate a relief signal upon the operation of said first relief device to relieve an overpressure condition within said first relief passage; (3) position sensor means operative to provide a position signal indicative of the position of said valve; and (4) controller circuit means having said motor means, said transducer means, said relief indicator means, and said position sensor means operatively connected thereto and responding to said relief signal from said relief indicator means indicating that the rupture disc associated therewith has ruptured by placing said valve in a second position providing full flow communication between said pressure passage and a second relief passage. - View Dependent Claims (8, 9, 10, 11, 12, 13, 14)
-
Specification