US1498096A

US1498096A - Emergency thrust balancing means

Info

Publication number: US1498096A
Application number: US468411A
Authority: US
Inventors: Herbert T Herr
Original assignee: Westinghouse Electric Corp
Current assignee: Westinghouse Electric Corp
Priority date: 1921-05-10
Filing date: 1921-05-10
Publication date: 1924-06-17
Anticipated expiration: 1941-06-17

Description

T he motor device 26 comprises an operating piston 28 arranged within the operating cylinder 29, the piston having a rod 30 connected to the valve'l4. The piston 28 normally occupies a position in the cylinder 29 between the conduit connection 21 with an inter-stage space of the turbine and the conduit connection 21 leading to the chamber 19. As the end of the conduit in the chamber 19 is normally closed, steam may leak bythe piston 28 and resultin the buildingup of pressure'therebeyond, tending to urge the piston in. such a direction as to open the valve 14. This tendency is also assisted by a spring 31 arranged between one end of the operating cylinder and one face of the piston As soon as the end of the conduit is opened in either of the ways referred to, pressure on the spring side of the operating piston 28 is suddenly relieved with the result that the turbine inter-stage pressure is efeffective to move the operating piston 28 in a direction to close the valve 14 and to occupy a position beyond the connection of the con- .duit portion 21' with the operating cylinder 29 such that the

connections

21 and 21 are in free communication to supply steam directly from the inter-stage space to the chamber 19.

Having thus described the arrangement of apparatus embodying my 1nvent1on,the op eration thereof is as follows: rlndernormal conditions, the spindle 11 is maintained in its proper longitudinal position by the thrust bearing 17 and does not bear against either the edge 20 of the septum 18 or against the end 23 of the conduit 21, and the conduit 21 the end thrust imposed thereupon and to i such an extent as to endanger the blading,

the spindle comes in contact with the thin edge 20, substantially closing chamber 19 and the end of the conduit 23 is then opened or unsealed, in the construction shown in Figure 2 by the fusion of the block 2e caused by the frictional heat engendered and by fracturing at the point 25 in the construction shown in Figure 3, the breaking 03 of the end of the conduit being facilitated by lugs 27 which may be mounted upon the spindle. The opening of the end of the conduit 23 at once admits fluid pressure to the f substantially closed space 19 to suchan extent as 'to substantially equalizethe pressures exerted upon the spindle 11, causing the same to assume and maintain its proper position.

When the fluid-pressure motor device 26 is inserted in the conduit 21, the motion of fluid through this conduit into the chamber 19 causes the throttle valve 14 to close, shutare specifically set "sition to said thrust.

mally assuming said thrust,

ting down the turbine or, if desired, the device 26 may be caused merely to ring an alarm device as where it is essential that the turbine remain in service.

Yvhile I have shown my invention in but two forms, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications without departing from the spirit thereof, and I desire therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or as forth in the appended claims.

hat I claim is: 1. The combination with a rotatable member subject to end thrust, of. a thrust hearing for normally assuming said thrust, a source of fit'llCl pressure, and means whereby, upon the'fa1lure of said thrust bearmgaud the consequent longitudinal movement of turbine having a spindle developing an end thrust, of a thrust bearing for normally assumlng said thrust, and means whereby, upon. the failure of said bearing to withstand said thrust and the consequent longitudinal movement. of saidspmdle, pressure of motive fluid is applied to sa1d spindle 1noppo- '3. The combination with a fluid-pressure turbine having a spmdle, the longitudlnal fluid pressure on said spindle normally being unbalanced,,of mechanical means for normally counteractmg said unbalance,'and

fluid-pressure means, operable upon a failure of said mechanical means, for acting said unbalance. 7

l. The combination with a fluid pressure turbine wherein an end thrust is developed upon its shaft, of a thrust bearing for nora pressure chamber adjacent the spindle of said turbine, and normally subject to relatively low pres sure, and means for admitting relatively high-pressure fluid to said chamber upon longitudinal movement of said spindle in excess of a predetermined amount, whereby said end thrust is counteracted.

5.. The combination with a fluid-pressure turbine wherein an end thrust is developed upon its shaft, of a thrust bearing for norcountermally assuming said end thrust, means for providing a pressure receiving surface on Cal tease-9 said faces forthe developmentofa pressure to substantially balance said end. thrust.

' 6L The combination witha1fluid pressure turbine wherein end thrust is developed upon its shaft, of athrust bearing for nor,- nially assuming said end thrust, means for providing a pressure receiving surface on saidspindlegfacing. thedireetion of thrust, an opposed fixed surface normally spaced therefrom by a slight amount, and a conduit connected to a; source of fluid pressure and terminating in a closed end disposed between said surfaces, the arrangement being such that upon longitudinal movement of said spindle in excess of a predetermined amount,

the end of said conduit is opened and fluid pressure is admitted to the space between said surfaces for the development of a pressure substantially balancing said end thrust.

7 The combination with a fluid-pressure turbine wherein an end thrust is developed upon its shaft, of a thrust bearing for normally assuming said end thrust, means for providing a pressure-receiving surface on said spindle facing in the direction of thrust, an opposed fixed surface normally spaced therefrom by a slight amount, a conduit connected to a source of fluid pressure and terminating in a closed end disposed between said surfaces, the arrangement being such that upon longitudinal movement of said spindle in excess of a predetermined amount, the end of said conduit is opened and fluid pressure is admitted to the space between saidsurfaces for the development of a pressure substantially balancing said end thrust, and means whereby the flow of fluid through said conduit cuts off the supply of motive fluid to said turbine.

8. The combination with a fluid-pressure turbine wherein an end thrust is developed along its shaft, of a thrust bearing for normally assuming said thrust, the spindle ofsaid turbine presenting a substantially plane surface in the direction of said thrust, a fixed cup-shaped member annularly disposed about the shaft of said turbine and concave toward said plane surface, said cup shaped member being provided with a thin edge adjacent to said plane face, and a conduit connected to a source of fluid pressure and terminating in a closed end closely adjacent to said plane face and within said cup-shaped member, the arrangement being such that upon longitudinal movement of said spindle in excessof a predetermined amount, said plane face substantially contacts with said thin edge and further contacts with the end of said conduit, opening said closed end and admitting fluid pressure to the substantially closed space thus formed, setting up a fluid pressure against said spindle to substantially balance said end thrust.

9. The combination with a fluid-pressure turbine wherein an end thrustis developed along the. shaft, of athrust bearing for, normally assuming said thrust, the spindle of said turbine presenting a substantially plane surface in the direction of said thrust, a fixed; cups-shaped member. annularly disposed about theshaft of said turbine and concaveitoward said plane surface, said cup shaped member being provided, with a thin edge adj-acentto said plane face, a conduit com ected; to a source of fluid pressure and terminating within said cup-shaped member and closely adjacent said plane face in a closed end, the arrangement being such that upon longitudinal movement of said spindle in excess of a predetermined amount, said plane face substantially contacts with said thin edge and further contacts with the end of said conduit, opening said closed end and admitting fluid-pressure to the substantially closed space thus formed, setting up a fluid pressure against said spindle to substantially balance said end thrust, and fluid pressure means whereby the flow of fluid through said conduit cuts off the supply of motive fluid to said turbine.

10. The combination with a fluid-pressure turbine wherein an end thrust is developed along the shaft, of a thrust bearing for normally assuming said thrust, the spindle of said turbine presenting a substantially plane surface in'the direction of said thrust, a fixed cup-shaped member annularly disposed about the shaft of said turbine and concave toward said plane surface, said cupshaped member being provided with a thin edge adjacent to said plane face, and a conduit connected to a source of fluid pressure and terminating within said cup-shaped member and closely adjacent said plane face in a closed end, said conduit being radically weakened ashort distance back from said end, whereby, upon a movement of saidspindle in the direction of thrust in excess of a predetermined amount, said cup member substantially contacts with said conduit end, breaking it off and admitting fluid pressure to said closed space for the development of a fluid pressure within said closed space substantially balancing said end thrust.

11. The combination with a fluid-pressure turbine wherein there is a gradation in pressure along the spindle resulting in an unbalanced end thrust on said spindle, of athrust bearing for normally assuming said end thrust, a pressure chamber adjacent said spindle and normally subject to relatively low pressure, and means for connecting said pressure chamber to a relatively high-pressure space of said turbine upon the longi tudinal movement of said spindle in excess of a predetermined amount and in the direction of said thrust, whereby a pressure is excited against said spindle to substantially balance said end thrust.

at I 1,498,096

' 12. The combination with a fluid-pressure turbine, wherein there is a gradation in pressure along the spindle resulting in an unbalanced end thrust on said spindle, of 'a thrust bearing for normally assuming said end thrust, a pressure chamber adjacent said spindle and normally subject to relatively low pressure, and a conduit connecting said pressure chamber with a relatively highpressure space in said turbine, said conduit termlnating w1th1n sa1d pressure chamber in a closed end closely adjacent an end portion of sa1d splndle, whereby upon excessive endwlse motion of sa1d spindle, said conduit end is opened and relatively high pressure fluid is admitted to said pressure chamber to counteract said end thrust.

In testimony whereof, I have hereunto subscribed my name this 3rd day of May, 1921.

HERBERT T; HERE,"