Valve control system for power generating plants

In a steam generating plant having a main steam line and a pivotally actuated valve movable between open and closed positions for controlling the flow of steam in said main steam line, a system for operating said main steam line valve comprising means for biasing said valve pivotally into said closed position, fluid actuating means for urging said valve pivotally into said open position against the action of said biasing means and means for supplying fluid under pressure to said fluid actuated means, said fluid supply means including a pump operatively connected to said fluid actuated means and a low flow rate exhaust valve and a high flow rate exhaust valve operatively connected to the pressure end of said pump.

In a steam generating plant having a main steam line and a pivotally actuated valve moveable between open and closed positions for controlling the flow of steam in said main steam line, a system for operating said main steam line valve comprising means for biasing said valve pivotally into said closed position, fluid actuated means for urging said valve pivotally into said open position against the action of said biasing means, means for supplying fluid under pressure to said fluid actuated means, said fluid supply means including a pump operatively connected to said fluid actuated means and at least one exhaust valve operatively connected to the pressure end of said pump, and means responsive to a predetermined pressure in the pressure end of said pump for operating said pump.

In a steam generating plant having a main steam line and a pivotally actuated valve movable between open and closed positions for controlling the flow of steam in said main steam line, a system for operating said main steam line valve comprising means for biasing said valve pivotally into said closed position, fluid actuated means for urging said valve pivotally into said open position against the action of said biasing means, means for supplying fluid under pressue to said fluid actuated means, said fluid supply means including a pump operatively connected to said fluid actuated means and at least one exhaust valve operatively connected to the pressure end of said pump, and means operatively connected to said pump and responsive to pressure in the pressure end of said pump for maintaining said pressure within a predetermined range.

In a steam generating plant having a main steam line and a pivotally actuated valve movable between open and closed positions for controlling the flow of steam in said main steam line, a system for operating said main steam line valve comprising means for biasing said valve pivotally into said closed position, fluid actuated means for urging said valve pivotally into said open position against the action of said biasing means, and means for supplying fluid under pressure to said fluid actuated means, said fluid supply means including a primary pump and a secondary pump having a capacity smaller than said primary pump operatively connected to said fluid actuated means and at least one exhaust valve operatively connected to the pressure ends to said pumps.

In a steam generating plant having a main steam line and a pivotally actauted valve movable between open and closed positions for controlling the flow of steam in said main steam line, a system for operating said main steam line valve comprising means for biasing said valve pivotally into said closed position, fluid actuated means for urging said valve pivotally into said open position against the action of said biasing means, and means for supplying fluid under pressure to said fluid actuated means, said biasing means comprising a spring assembly, said fluid actuating means including a fluid cylinder assembly having a rod operatively connected to said valve and a cylinder end operatively connected to said fluid supply means, said fluid actuated means including first and second crank arm members connected to and pivotal about a pivot axis of said valve, said first crank arm member being operatively connected to the rod of said fluid cylinder assembly and said second crank arm member being operativley connected to said biasing means, and said fluid supply means including a pump operatively connected to said fluid actuated means and at least one exhaust valve operatively connected to the pressure end of said pump.

In a steam generating plant having a main steam line and a pivotally actuated valve movable between open and closed positions for controlling the flow of steam in said main steam line, a system for operating said main steam line valve comprising means for biasing said valve pivotally into said closed position, fluid actuated means for urging said valve pivotally into said open position against the action of said biasing means, and means for supplying fluid under pressure to said fluid actuated means, said fluid actuated means including first and second crank arm members connected to and pivotal about a pivot axis of said valve, said first crank arm member being operatively connected to the rod of said fluid clyinder assembly, said second crank arm member being operatively connected to said biasing means, said biasing means comprising a canister spring assembly, said second crank arm member being operatively connected to a movable canister section thereof, and said fluid supply means including a pump operatively connected to said fluid actuated means and at least one exhaust valve operatively connected to the pressure end of said pump.

In a steam generating plant having a main steam line and a pivotally actuated valve movable between open and closed positions for controlling the flow of steam in said main steam line, a system for operating said main steam line valve comprising a spring assembly for biasing said valve pivotally into said closed position, fluid actuated means for urging said valve pivotally into said open position against the biasing action of said spring assembly and means for supplying fluid under pressure to said fluid actuated means, said fluid supply means including a pump operatively connected to said fluid actuated means and at least one exhaust valve operatively connected to the pressure end of said pump.

In a steam generating plant having a main steam line and a pivotally actuated valve movable between open and closed positions for controlling the flow of steam in said main steam line, a system for operating said main steam line valve comprising means for biasing said valve pivotally into said closed position, fluid actuated means for urging said valve operatively into said open position against the action of said biasing means, and means for supplying fluid under pressure to said fluid actuated means, said biasing means comprising a canister spring assembly having a movable canister section operatively connected to said fluid actuating means, and said fluid supply means including a pump operatively connected to said fluid actuated means and at least one exhaust valve operatively connected to the pressure end of said pump.

In a steam generating plant having a main steam line and a pivotally actuated valve movable between open and closed positions for controlling the flow of steam in said main steam line, a system for operating said main steam line valve comprising means for biasing said valve pivotally into said closed position, fluid actuated means for urging said valve pivotally into said open position against the action of said biasing means and means for supplying fluid under pressure to said fluid actuated means, said fluid supply means including a pump having the pressure end thereof constantly communicating with said fluid actuated means and at least one exhaust valve connected to the pressure end of said pump, normally disposed in a closed position and selectively operable to open the valve.