Patent Application
20160319700
This application claims priority to European Patent Application No. 15290115.3 filed Apr. 29, 2015, the contents of which are hereby incorporated in its entirety.
The present disclosure relates to a pressure regulating system for lubricating a turbo machine to and more particularly a system and method for regulating the pressure in a nuclear steam turbine.
Nuclear steam turbines mostly use centrifugal pumps to supply fluids especially lubricants oil. Apart from the centrifugal pumps, oil lubricant system of the nuclear steam turbines is fed in a normal operation by a pump which delivers a constant flow. During the operation of the nuclear steam turbine as per requirement several pumps are started or stopped or any other anomaly in pressure leading to sudden variation at lubricant oil manifold. These sudden lubricant oil pressure variation leads to the nuclear steam turbines trip. Also the current lubricant systems of the nuclear steam turbines are static and not respond to sudden requirement of the nuclear steam turbines. The tripping of the nuclear steam turbines is not good for the overall plant.
Consequently, there is need to provide a pressure regulating system which is simple in operation, easy in installation, less expensive in capital cost and more effective in tackling the sudden variations of the nuclear steam turbines and avoid the tripping of the nuclear steam turbines.
The present disclosure describes a system and method for regulating the pressure in a turbo machine particularly nuclear steam turbine. This will be presented in the following simplified summary to provide a basic understanding of one or more aspects of the disclosure including all advantages. The sole purpose of this summary is to present some concepts of the disclosure, its aspects and advantages in a simplified form as a prelude to the more detailed description that is presented hereinafter.
An object of the present disclosure is to propose a system and method for regulating the pressure in a turbo machine particularly nuclear steam turbine which can be used in existing and in new unit installations to significantly reduce the emission of these pollutants.
The present invention offers a technical solution of controlling variation accurately of pressure at manifold of a pressure regulating system. The solution is to modify pressure regulating system by a dedicated arrangement of bypass which control variations of pressure at the manifold dynamically by responding adequately due to sudden variations of nuclear steam turbines by closing the pressure regulating system in less time than a regular time which leads to restoration of full supply of lubricant oil to the nuclear steam turbine in response of the sudden variations which can be tackled by supplying the adequate amount of the lubricant oil which is required for the working as well as avoiding the tripping of the nuclear steam turbine.
Various other objects and features of the present disclosure will be apparent from the following detailed description and claims.
According to one aspect disclosed herein, there is provided a pressure regulating system for a turbo machine comprising a body member having a moving member, an opening and a sealing member. Further a first biasing member for keeping the moving member at a closed position is provided. An actuating line, extended from a main supply line to the pressure regulating system, for actuating on the moving member to counter the bias member by filing pressurized fluid to a preset value into a manifold. An impulse line, extended from the pressure regulating system to the main supply line for supplying the pressurized fluid in at least one chamber of the moving member to lift the moving member to an open position, leads to opening of the sealing member to drain the manifold through the opening.
In another aspect the moving member moves from the open position towards the closed position in a normal time period when the pressure in the impulse line is equal to a lubrication pressure in the turbo machine.
In yet another aspect a bypass is installed between the moving member and the manifold for a fast evacuation of the fluid in a time period less than the normal time period.
In yet another aspect the bypass leads to an early closing of the moving member, increase closing tendency of the moving member.
In yet another aspect, the bypass comprises an inlet opening to receive the fluid form the chamber of the moving member, an outlet opening to drain the fluid from the bypass to the manifold. A closing member is actuated by the flow of the fluid and a second biasing member to counter movement of the closing member.
In the pressure regulating system the moving member responds to the pressure requirements, adapting its position as efficiently as possible, to allow the flow of lubricant if the pressure is high in the turbo machine, or close if the pressure is low in the turbo machine.
The present disclosure also refers to a method for regulating pressure in a turbo machine comprising keeping a moving member through a first biasing member at a closed position, actuating on the moving member through an actuating line, the actuating line extended from a main supply line to the pressure regulating system countering the bias member by filing pressurized fluid into a manifold, permitting the pressure of the pressurized fluid to increase to a preset value in the manifold, supplying the pressurized fluid through an impulse line at least one chamber of the moving member, the impulse line extended from the pressure regulating system to the main supply line, lifting the moving member to an open position which leads to opening of the sealing member to drain the manifold through the opening.
In another aspect, moving the moving member from the open position towards the closed position in a normal time period when the pressure in the impulse line is equal to a lubrication pressure in the turbo machine.
In yet another aspect, a bypass is installed between the moving member and the manifold and evacuating the fluid in a time period less than the normal time period.
In yet another aspect, increasing closing tendency of the moving member and closing the moving member earlier than the normal time period.
In yet another aspect, receiving the fluid form the chamber of the moving member through an inlet opening in the bypass, actuating at least one closing member in the bypass by the flow of the fluid, countering movement of the closing member in the bypass through at least a second biasing member, draining the fluid from the bypass to the manifold through an outlet opening.
These together with the other aspects of the present disclosure, along with the various features of novelty that characterize the present disclosure, are pointed out with particularity in the present disclosure. For a better understanding of the present disclosure, its operating advantages, and its uses, reference should be made to the accompanying drawings and descriptive matter in which there are illustrated exemplary embodiments of the present disclosure.
The advantages and features of the present disclosure will be better understood with reference to the following detailed description and claims taken in conjunction with the accompanying drawings, wherein like elements are identified with like symbols, and in which:
As shown in
In case when the second force in the impulse line 70 is less than the preset value of the force which is fixed in the pressure regulating system 10, the first biasing member 40 will come down to push the plate 260 onto the head 250 of the moving member 30 to push it towards the closed position 100. The moving member 30 start moving from the open position 110 towards the closed position 100 in a normal time period when the pressure in the impulse line 70 is equal to a required lubrication pressure in the nuclear steam turbine. While closing, the fluid is evacuated. The impulse line 70 extends from the pressure regulating system 10 to the main supply line 310.
The movement of the pressure regulating system 10 is slow due to the hydraulic restrictions of the impulse line 70. For nuclear power plant, the lubricant oil pumps are large and produce large pressure variations when switched on or switched off.
In order to increase the closing tendency of the pressure regulating system 10, a bypass 120 is installed between the moving member 30 and the manifold 170 for a fast evacuation of the fluid in a time period less than the normal time period. The bypass 120 allows faster evacuation of the volume of fluid to the manifold 170 if the difference of pressure between the impulse line 70 and the manifold 170 is higher than a pre-set value. The bypass 120 leads to an early closing of the moving member 30, increase closing tendency of the moving member 30. On the other hand the opening motion of the moving member 30 is unchanged. No fluid is evacuated through impulse line 70.
In a method for regulating pressure in a turbo machine for example a nuclear steam turbine 180 keeping a moving member 30 for example a piston through a first biasing member 40 at a closed position. The moving member 30 is actuated on through an actuating line 60 countering the bias member 40 by filing pressurized fluid into a manifold 170. The pressure of the pressurized fluid is permitting to increase to a preset value in the manifold 170, lifting the moving member 30 to an open position 110 which leads to opening of the sealing member 80 to drain the manifold 170 through the opening 50. An impulse line 70 is supplying the pressurized fluid through in chambers 90, 270 of the moving member 30.
The moving member 30 is moving from the open position 110 towards the closed position 100 in a normal time period when the pressure in the impulse line 70 is more than the manifold 170. In order to increase the closing tendency of the pressure regulating system 10, a bypass 120 is installed between the moving member 30 and the manifold 170 which evacuate the fluid in a time period less than the normal time period. Particularly closing tendency of the moving member 30 is increased through the bypass 120 and the moving member 30 is closed earlier than the normal time period. The bypass 120 is receiving the fluid form the chambers 90, 270 of the moving member 30 through an inlet opening 160. A closing member 130 in is actuating by the flow of the fluid. The movement of the closing member 130 is countered through a second biasing member 140. Further the fluid from the bypass 120 to the manifold 170 is drained through an outlet opening 150.
The foregoing descriptions of specific embodiments of the present disclosure have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present disclosure to the precise forms disclosed. Many modifications and variations are possible in light of the above examples. The embodiments were chosen and described in order to best explain the principles of the present disclosure and its practical application, to thereby enable others skilled in the art to best utilize the present disclosure and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions and substitutions of equivalents are contemplated as circumstance may suggest, or render expedient, but such are intended to cover the application or implementation without departing from the spirit or scope of the claims of the present disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 15290115.3 | Apr 2015 | EP | regional |
