US1294532A - Fluid-distributing valve mechanism. - Google Patents

Description

Patented Feb. 18, 1919.

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A TTOR NE Y D. M. RADOVA NOYVITCH. FLUID DISTRIBUTING VALVE MECHANISM. APPLICATION FILED JULY 3. I914.

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APPLICATION FILED JULY 3. 1914.

Patented Feb. 18, 1919.

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DEMETRIUS 1V1. RADOVANOVITCI-I, OF PITTSBURGH, PENNSYEVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC &, MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

Specification of Letters Patent.

Patented Feb. 18, 1919.

Application filed July 3, 1914. Serial No. 848,838.

To all whom it may concern Be it known that I, DEMETnIUs M. RADO- VANOVITGH, a citizen of Switzerland, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have made a new and useful Invention in Fluid- Distributing Valve Mechanism, of which the following is a specification.

This invention relates to conservation of the exhaust steam from the auxiliaries of a power plant.

In power plants the feed water for the boilers or steam generators is often heated V by exhaust steam from the auxiliaries; that is, by the steam exhausted from the feed water pumps, circulating pumps, etc. Under some operating conditions it is diflicult to proportion the number of non-condensingauxiliaries delivering steam to the feed water heater so as to obtain a high degree of etiiciency and at the same time maintain desired feed water temperatures for all loads on the main unit, vhich, for convenience, may be termed the prime mover. For example, the non-condensing auxiliaries may be so arranged that sufficient steam is dehvered by them to the feed water heater to maintain the temperature of the feed water at 210 degrees F. While the prime mover is operating under normal load conditions. With such an arrangement a decrease in the load on the prime mover will occasion a decrease in the amount of steam used, while the amount of steam delivered from the auxiliaries will remain substantially constant. The result is that more steam is delivered to the feed water heater than can be utilized in heating the water to the desired temperature and consequently the excess steam will escape to the atmosphere with attend-ant losses. On the other hand, an increasing load on the prime mover will occasion the use of more steam and a correspondingly larger amount of feed water. The exhaust steam delivered from the auxiliaries will, however, remain substantially constant and will be incapable of heatingthe feed water to the desired temperature.

An object of this invention is, therefore, to produce an improved system for heating the feed water, by means of the exhaust steam from the auxiliaries, which will eliminate to a large extent, the losses during light loads on the prime mover and will maintain the feed water at substantially the desired temperature during heavy as Well as light loads on the prime mover.

A further object is to produce improved means, which when employed in connection with a feed water heating system receiving steam from the auxiliaries, will deliver the excess steam exhausted from the auxiliaries to a prime mover and will also deliver an augmenting supply of steam to the feed water heater during heavy loads on the prime mover.

A further and more specific object is to produce a valve mechanism capable of delivering excess steam from the auxiliaries to a prime mover, or of delivering augmenting steam from the prime mover to the feed water heater, and of shutting 0d communication between the prime mover and the heater when the pressure within the prime mover is such as to produce an objectionable back pressure on the auxiliaries communicating with the heater.

These and other objects I attain by means of a heating system embodying the features herein described, and illustrated in. the drawings accompanying and forming a part of th1s application.

In the drawings, Figure I is a diagrammatic view of a feed water'heater' and a turbine shown in connection with an automatic valve mechanism embodying my invention, and such as is shown in detail in Fig. a; portions of the turbine casing are shown broken away for convenience of illustration.

Fig. 2 is a vertical sectional. View of a valve mechanism embodying my invention.

Fig. 3 is a corresponding view of a modiauxiliaries througha supply pipe 9. The,

exhaust steam from the heater is delivered through a pipe 10 to a valve mechanlsm ll and from the valve mechanism to a prime mover, such for example, as a turbine 12.

The valve mechanism shown in Fig. 1 as .an embodiment of my invention is capable of not only admitting excess steam from the heater to the turbine but is also capable of augmenting the steam supply to the heater when the steam exhausted from .the auxiliaries is insuflicient to maintain desired temperatures in the heater. In addition to this the valve mechanism is capable of shutting ofi communication between the turbine and the heater when the operating conditions are such that the pressure within the turbine would exert an objectionable back pressure on the auxiliaries comn'iunicating with the heater. The pipe or passage 10 is shown as provided with a relief valve 13, which is adapted to discharge the excess steam from the heater into the atmosphere when the conditions are such that the excess is not delivered to the turbine.

In Fig. 2, I have shown one embodiment of my invention, in which the valve mechanism includes a casing 14:, having a port 15 adapted to receive excess steam from the heater 10, or from any other source of low pressure supply, and a port 16 which is adapted to communicate with an inlet port or ports of a prime mover. The casing in cludes a valve or piston 17, which operates in a cylindrical chamber 18, forming a. part of the valve casing, and adapted to control the delivery of steam from the port 15 to the port 16. The chamber 18 is provided near its lower end with a series of ports 19, which are annularly arranged around the chamber 18, in open communication with the port 16, and are adapted to be closed by the valve 17 when it is moved to its lower, or port closing position. The lower end of the chamber 18 communicates with the port 15 through ports 21, and the upper portion of the chamber 18 is subjected to atmospheric pressure through a port or passage 22.

Under such conditions, the piston 17 will rise and open the ports 19, thereby establishing direct communication between the ports 15 and 16, when the pressure of the steam delivered through the port 15 exceeds atmospheric pressure an amount sufli cient to overcome the weight of the piston.

The casing 14 also contains a valve or piston 23, which is capable of moving in response to a preponderance of pressure at the port 16 over that existing at the port 15. This piston is located in an extension of the cylindrical wall inclosing the chamber 18,

and is subjected on its lower face to the pressure existing in the passage 24, and consequently at the port 16, since the passage 21 is in open communication with the port. The cylindrical extension surrounding the piston 23 is provided with an annular series of ports 25, across which the piston 23 is adapted to move, and with which the port 15 is in open communication. The upper face of the piston 23 is exposed to the pressure existing at the port 1.5 through the ports 21.

With such an arrangement, the piston 23 will lift and establish communication between the port 16 and the port 15, when the pressure at the port 16 exceeds the pressure at the port 15 an amount capable of overcoming the weight of the piston 23, and this will occur whether the pressure at the port 16 is in excess of atmospheric pressure or not.

The piston 23 is provided with a stem 26, which extends upwardly through the valve casing 14 and projects beyond the casing, so that it is capable of being engaged by a closing means, such as a plunger actuated yoke 27 shown in the drawing. The piston 17 is also provided with a stem 28, which projects beyond the casing and which, like the stem 26, is capable of being engaged by the yoke 27.

For the purpose of obtaining a compact structure, the piston rod or stem 28 is shown hollow and surrounding the rod or stem 26, and both stems are provided with suitable packings which are primarily arranged to prevent leakage of air into the valve casing, although they also prevent leakage of steam from the casing to the atmosphere.

In the drawings I have shown means for moving both the pistons 17 and 23 to closed positions in which they respectively seat on shoulders 31 and 32 formed within the casing 1 1, and when the turbine or prime mover. with which the port- 16 communicates, ex ceeds a predetermined or safe speed. As illustrated, this means consists of a plunger 37 operating within a cylinder 33, which communicates, through a port 34, with a source of fluid supply and through a port 35 with a passage 36, which communicates with the exhaust or with the atmosphere through a governor control valve 36. This apparatus merely forms a detail of the present invention and may be materially varied in details of construction, or may be replaced by any suitable governor control apparatus for closing both the valves. The plunger 37 is provided with a rod or stem 38, which is rigidly connected to the yoke 27 When the plunger moves in response to the opening of the exhaust passage 36, to its lowermost position, or to the position shown in the drawing, the yoke 27 is moved downwardly by it and engaging both of the stems 26 and 28, closes both of the valves 23 and 17 and holds them closed until the plunger 37 is raised. The closing of the valves 17 and 23 shuts oii communication between the ports 15 and 16 and absolutely cuts 01f the delivery of steam through the port 16.

In Fig. 3, I have shown a modification of my invention in which the valve mechanism embodying it is provided with means, responsive to the pressure of steam at the port 16, for closing the valve 23 when the pressure at the port 16, and consequently in the passage 24, exceeds a determined pressure above that deemed desirable to subject the exhaust passages and the auxiliaries; or in other words, a pressure in excess of a desirable back pressure on the auxiliaries.

The valve mechanism illustrated in Fig. 3 is'similar in many respects to the mechanism illustrated in Fig. 2 and includes the valves or pistons 17 and 23, the ports 15 and 16, and the operating rods or stems 26 and 28. The passage 24, which communicates with the port 16v and subjects the lower face of the piston 23 to the pressure existing at the port 16, is enlarged so as to include a cylindrical chamber 39, the walls of which are formed integrally with the valve casing 14. The chamber 39 contains a piston 41 and its lower end is in open communication with the passage 24, so that the bottom of the piston issubjected to the pressure of that'chainber. The piston 41 is provided with a rod or stem 42, which projects through the casing, and which is connected by any suitable means, such as a link to a lever 43, pivoted on a bracket'of the valve casing 14. One end of the lever is operatively connected to a collar 44, engaged by the rod 28 of the piston 23, and the lever is adapted, through theagency of its connection with the collar, to move the piston 23 to its seat and thereby close the ports 25 when the piston 41 lifts in response to the pressure within the chamber 24. The upperside of the piston 41 is exposed to atmospheric pressure through a port 46, formed in the casing 14 and means, such for example, as a Weight 47, adjustable longitudinally of the lever 43, is provided for varying the effective weight of the piston and consequently for adjusting the apparatus so that the piston 41 will lift in response to different pressures within the chamber 24. As shown in the drawing, the collar 44 is arranged to engage the projecting end of the rod or stem 26 of the piston 17, and consequently will insure the seating of both of the pistons 17 and 23 when the piston 41 lifts.

The Operation of the apparatus shown is somewhat as follows. When the exhaust pressure of the, auxiliaries, or the excess steam from the heater in the pipe or'passage 1O exceeds atmospheric pressure by an amount capable of overcoming the weight ofthe piston, the piston 17 will lift and steam will be delivered from the passage 10,

through theport 15, the ports 21, the ports 19,,the passage 24 andthe port 16 to a low pressure stage of a prime mover, it being understood that the port 16 is adapted to communicate with a low pressure stage of a prime mover, such as a turbine. If for anyreason the amount of excess steam traversing'the passage 10 falls to or below atmospheric pressurefthe piston 17 will seat and shut off communication between the ports 15 and 16. If now,the pressure in the low pressure stage of the turbine communicating with the port 16 exceeds the pressure of the exhaust steam in the passage 10, a determined amount, the piston 23 will lift and steam will be delivered from the prime mover through the ports 25, the port 15 and the passage 10 to augment the exhaust steam from the auxiliaries delivered to the heater. If the load conditions are such on the prime mover that the pressure in the passage 24 increases to such an extent that an objectionable back pressure will be imposed upon the auxiliaries communicating with the feed water heater, the/piston 41 will lift and will seat the piston 23 and thereby shut off the communication between the ports 15 and 16. As above described, the lifting of the plunger 41 will seat both of the pistons 17 and 23, if the pressure conditions are such that they both happen to be open. It will be apparent that the weight 47 on the lever 43 may be employed for adjusting the mechanism to vary the amount of pressure necessary to open the valve 23 as well as the pressure necessary to liftthe plunger 41 and close the valve.

The valve mechanism like the mechanism illustrated in Fig. 2, is also provided with a plunger 37 and its accessories for seating both the pistons 17 and 23 and holding them in the closed position when the prime mover exceeds a determined speed. a

In Fig. 4, I have shown an embodiment of my invention, in which the pressure actuated plunger 41 operates, through the agency of a relay valve 49 to move the pistons 17 and 23 to close communication between the ports 15 and 16.

The relay valve controls the delivery of operating fluid to and the exhaust of operating fluid from a cylinder 51, which contains a piston 52. The piston rod of the piston 52 is adapted to depress or move both of the stems 28 and 26 to seat their respective pistons 17 and 23. The valve 49 is so arranged that in one position, for example the lower position, it will deliver fluid under pressure to the lower side of the piston 52 and connect the upper end of the cylinder 51 with the exhaust. This will raise the piston 52 and move it to such a position that it will not hamper or in any way interfere with the opening or lifting of either the pistons 17 or 23. lVhen, however, the relay valve is moved in the opposite direction, or to the position shown in the drawing, it will admit fluid under pressure to the cylinder 51 on the upper side of the piston 52, and will connect the lower end of the cylinder with the exhaust. This will cause the piston to move downwardly and thereby move its stem into engagement with the rod 26 and closethe valve 23, or into engagement with &

both the rods 26 and 28, if both of the pistons l7 and 23 are raised, and thereby close both valves. The relay valve illustrated is similar in construction to the relay valves ordinarily employed and, for that reason, will not be described in detail.

In the drawings I have shown the rod 42 of the piston 42]. connected with a weighted lever 43", one end of which is pivotally mounted on a bracket carried by the casing 14, while the other or weighted end projects through an elongated slot 5e formed in a rod 54, which is connected to a plunger 55 operating within a cylinder 56. The opera- -tion of the piston 55 is controlled by an automatic stop governor in a manner similar to that described in connection with the plunger 37, forming the part of the apparatus illustrated in Figs, 2 and 3. Fluid under pressure is admitted to the cylinder at a point below the plunger through a port or passage 57, While fluid is adapted to be exhausted from the upper end of the cylinder above the plunger through a port 58 and a, communicating passage 59. Theexhaust of fluid through this passage is, however, controlled by a governor actuated valve, which is arranged to open when the prime mover with which the port 16 communicates, exceeds a determined speed. It will be understood that the cylinder 56 of Fig. & and the cylinders 33, of Figs. 2 and 3, are each provided with means for admitting fluid to the exhaust side of the piston, such for example, as means for permitting a restricted flow of actuating fluid around the plunger, so that when the valve in each exhaust passage is closed, the pressure on opposite sides of the corresponding plunger is equalized and the plunger moves or is moved by some force such as spring pressure to the inlet end of its respective cylinders. The slot 54: in the rod 54: is of such length that the piston 41 is capable of moving unchecked throughout its entire range of motion when the piston 55 is in its lowermost position, or at the inlet end of the cylinder 56 as illustrated in the drawing. The travel of the piston 55 is, however, so proportioned with relation to the length of the slot, the travel of the valve 49 and the length of the lever 43 that when it moves to its uppermost position in response to the opening of exhaust passage 59, it will move the valve 49 to its uppermost position, that is, the position shown in the drawing, and will effect a seating of the pistons 17 and 23 through the operation of the plunger 52.

While I have illustrated several embodi ments of my invention, each of which is arranged to deliver excess steam from a feed water heater to a turbine and to deliver an augmenting supply of steam from the turbine to the heater, it will be understood that I do not limit myself to the application of my invention to feed water heaters and prime movers, such as turbines, since it may be employed in connection with any apparatus in which it is desirable to maintain efficiency, first by efltectively utilizing the excess motive fluid from a source of low pressure supply, and second by augmenting the low pressure supply by motive fluid which has previously been expanded in doing work. It will also be understood that various changes, modifications, additions, omissions and substitutions may be made in the apparatus illustrated without departing from the spirit and scope of my invention as set forth by the appended claims.

Having thus described my invention, what I claim is:

1. In combination with a source of low pressure motive fluid, a valve responsive to the pressure of fluid from said source for delivering fluid therefrom to a fluid actuated engine, and means responsive to the fluid pressure within said engine for delivering fluid from said engine to saidsource.

2,. In combination with a source of low pressure motive fluid, a valve responsive to the pressure of fluid from said source for delivering fluid from the source to a power transmitting mechanism, and a valve responsive to fluid pressure within said mechanism for delivering fluid from the mechanism to augment the supply of fluid from said source.

3. In combination with a source of low' pressure motive fluid, means responsive to the pressure of fluid to said source for delivering fluid therefrom to a low pressure working passage of a multi-expansion fluid actuated engine, and means responsive to the pressure within the working passage of said engine for delivering augmenting fluid to said low pressure source of supply from said engine.

4:. In combination with a source of low pressure motive fluid, means responsive to the pressure of fluid from said source for delivering fluid therefrom to an apparatus for expanding the fluid in doing work, and means responsive to pressure within said apparatus for augmenting the fluid of said source with fluid which has been expended in doing effective work.

A heating system comprising a source of low pressure steam, a heater receiving steam from said source, a pressure actuating engine, means responsive to the pressure of steam from said source for delivering the excess steam from the heater to said engine, and means responsive to a preponderance of pressure within a working passage of the engine over the pressure of the fluid from the source for establishing communication between the engine and the source forcdelivering an augmenting supply of steam from the engine to the heater.

6. In combination with a fluid pressure engine and a source of low pressure motive fluid, a piston valve directly subjected to fluid from the source of low pressure fluid and movable in response to the pressure of said fluid to deliver fluid from the source to the engine, and means responsive to the speed of the engine for actuatlng said valve to close communication between the engine and the source and for holding the valve in the closed position.

7. In combination with a fluid pressure engine and a source of low pressure fluid,

means responsive to the pressure of fluid gine and a source of low pressure fluid supply, means responsive to the pressure of fluid from the source for delivering fluid therefrom to the engine, means responsive to fluid pressure within a working passage of the engine for delivering an augmenting supply of fluid from the engine to the source, and means responsive to the speed of the engine for actuating one or both of said means to close communication between the source and the engine.

9. In combination with a fluid pressure engine and a source of low pressure fluid, a. valve responsive to the pressure of fluid from the source for delivering fluid therefrom to the engine, a valve responsive to fluid pressure within a. working passage of the engine for delivering an augmenting supply of fluid therefrom to the source, and means responsive to the speed of the engine for moving and holding both valves in a closed position when the engine exceeds a determined speed.

10. In combination with a fluid pressure engine and a source of low pressure fluid, a valve mechanism comprising a valve subjected on one side to atmospheric pressure and on the otherto the pressure of fluid from the source, for delivering fluid from the source to the engine, and a valve responsive to a preponderance of pressure within a working passage of the engine for deliverlng low pressure fluid from the engine to the source.

11. In combination with a fluid pressure engine and a source of low pressure fluid, a

valve mechanism comprising a valve subjected to atmospheric pressure and responsive to the pressure of fluid from the source for delivering fluid therefrom to the engine, a second valve responsive to the difl'erence in pressure between the fluid in a working passage of the engine and at the source of low pressure supply for delivering augmenting fluid tromthe engine to the source, and speed responsive means for closing both valves when the speed of the engine exceeds a determined speed.

12. A heating system comprising a source of low pressure steam, a heater receiving steam from the source, a pressure actuated engine, means responsive to the pressure of fluid from the source for delivering excess steam from the heater to the engine, means responsive to a preponderance of pressure within a working passage of the engine over the pressure of the fluid from the source for delivering an augmenting supply of steam fromthe engine to the heater, and means responsive to the pressure of steam delivered from the engine for closing communication between the engine and the heater when the pressure of the steam from the engine exceeds a determined pressure.

13. In combination with a source of fluid supply and a multi-expansion engine, means responsive to the pressure of fluid from said source for delivering fluid therefrom to a low pressure stage of the engine, means responsive to the preponderance of pressure in the low pressure stage over the pressure of the source for delivering steam from the engine to the source, and means responsive to the pressure of fluid at the low pressure stage for closing communication between the source and the engine.

14. In combination with a source of supply and a multi-stage engine, meansresponsive to the pressure of fluid from the source for delivering fluid therefrom to a low pressure stage of the engine, means responsive to the preponderance of pressure in the low pressure stage over the pressure of the source for delivering low pressure fluid to the source, and means subjected to atmospheric pressure and responsive to the pressure of fluid delivered from the engine for closing communication between the engine and the source when the fluid delivered from the engine exceeds atmospheric pressure a determined amount.

15. In combination with the source of supply and a multistage engine, means responsive to the difference between atmospheric pressure and the pressure of fluid delivered from said source for delivering fluid from the source to the low pressure stage of the engine, means responsive to the preponderance of pressure in the low pressure stage over the pressure at the source for delivering fluid from the engine to the source, and means subjected to atmospheric pressure and responsive to the fluid delivered from the engine for closing communication between the engine and the source when the pressure of fluid from the engine exceeds a determined pressure. 7

16. In combination with a fluid pressure engine, a source of low pressure fluid supply, a valve for controlling communication between said engine and said source, and means responsive to the pressure within the working passage of the engine for closing said valve when said pressure increases beyond a predetermined amount.

17. In combination with a fluid pressure engine, a source of low pressure fluid supply, a valve subjected to a substantially constant closing pressure and responsive in operation to variations in the pressure of said source for controlling communication between the source and the engine, and a second valve responsive to the preponderance of fluid pressure within the working passage of the engine, over the pressure at the source, for delivering augmenting fluid from the engine to the source.

18. In combination with a fluid pressure engine, a source of low pressure fluid supply, a valve subjected to a substantially con stant closing pressure and responsive in operation to variations in the pressure of said source for controlling communication between the source and the engine, a second valve responsive to the preponderance of fluid pressure within the working passage of the engine, over the pressure at the source, for delivering augmenting fluid from the engine to the source, and a pressure actuated motor for closing both valves when the speed of the engine exceeds a determined speed.

19. A system of the character described, comprising a heater, a source of low pressure steam supply from which steam is delivered to the heater, apparatus receiving steam from a separate source of supply, a valve responsive to the pressure of fluid within the heater for delivering steam therefrom to said apparatus. and a valve responsive to a preponderance of steam pressure within said apparatus over the steam pressure within the heater for controlling the delivery of steam from the apparatus to the heater.

20. In combination with a fluid pressure engine, receiving steam from a source of: high pressure steam supply, a source of low pressure steam supply, and two valves for controlling connnunioation between said source of low pressure steam supply and a worklng passage of the engine, one of said valves being responsive to the pressure of the steam at the low pressure source and the other to a preponderance of pressure within the working passage of the engine over the pressure of the source of low pressure steam.

Ql. In combination with a fluid pressure engine, receiving steam from a source of high pressure steam supply, a source of low pressure steam supply, two valves for controlling communication between said source of low pressure steam supply and a working passage of the engine, one of saidvalves,

being responsive to the pressure of the steam at the low pressure source and the other to a preponderance of pressure within the working passage of the engine over the pressure of the source of low pressure steam, and means responsive to the speed of the engine for closing both valves. 7

22. In combination with a fluid pressure engine receiving steam from asource of high pressure steam supply, a source of low pressure steam supply, two valves for controlling communication between said source of low pressure steam supply and a working passage of the engine, one of said valves being responsive to the pressure of the steam at the low, pressure source and the other to a preponderance of pressure within the working passage of the engine over the pressure of the source of low pressure steam, and means responsive to the pressure Within the working passage of the engine for closing both valves. p 7

23. In combination with a fluid pressure engine, receiving steam from a. source of highpressure steam supply, a source of low pressure steam supply, two valves for controlling communication between said source of low pressure steam supply and a working passage of the engine, one of said valves being responsive to the pressure of the steam at the low pressure source and the other to a preponderance of pressure within the working passage of the engine over the pressure of the source of low pressure steam, means responsive to the speed of the engine for closing both valves, and means responsive to pressure within the working passage of the engine for closingboth valves.

.24. A system of the characterdescribed, comprising a heater, a source of low pressure steam supply from which steam is delivered to the heater, apparatus receiving steam from a separate source of supply, a valve responsive to the pressure of fluid within the heater for delivering steam therefrom to said apparatus, a valve responsive to a preponderance of steam pressure within said apparatus over the steam pressure within the heater for controlling the delivery, of steam from the apparatus to the heater, and means responsive to the pressure within the apparatus for closing both valves.

25. In combination with a fluid pressure engine and a source of low pressure motive fluid, a valve responsive to the pressure of fluid from said source for delivering motive fluid therefrom to said engine. a valve responsive to a preponderance of pressure of the fluid within the engine over the pressure of fluid at the source for delivering motive fluid from the engine to the source, and means for closing both of said valves when the pressure within the engine increases beyond a predetermined amount;

26 In combination with a fluid pressure engine and a source of low pressure motive fluid, a valve responsive to the pressure of fluid from said source for delivering motive fluid therefrom to said engine, a valve responsive to a preponderance of pressure of the fluid Within the engine over the pressure of fluid at the source for delivering motive fluid from the engine to the'source, means for closing both of said valves when the pressure Within the engine increases beyond subscribed my name this 30th day of June, 15

DEMETRIUS M. RADOVANOVITCH. Witnesses:

C. W. MGGI-IEE,

E. W. MoCALLIsTnR.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents Washington, D. G.

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