US1151522A - Oil-actuated valve mechanism for steam-turbines. - Google Patents

Description

F. HODGKINSON.

mL AcuATED vALvE MecHAmsM Foa STEAM TURBINES.

APPLICATION FILED FEB-10. l90. 5 1,151,522, Patented Aug. 24, 1915.

4 SHEETS-SHEET1.

INVENTOR JATTORNEY/N FACT.

WIl

F. HODGKINSON.

on. ACTUATED VALVE MECHANISM FOR STEAM TURBINES.

APPLICATION FILED FEB. I0, 1910.

PateuedAuO. 24, 1915.

4 SHEETS-SHEFT 2 INVENTOR.

TTRNEY IN FACT.

WITN S F. HODGKINSON. OIL ACTUATED VALVE MECHANISM FOR STEAM TURBINES. APPLICATION FILED Fis, 1o. 1910.

1,151,522. Patented Aug. 24, 1915.

4 SHEETS-SHEET 3.

INVENTOR.

, MW H F. HODGKINSDN.

OIL ACTUATED VALVE MECHANISM FOR STEAM TURBINES.

APPucATxoN msu FEB. 10. mo.

1 ,1 5 1 ,522. Patented Aug. 24, 1915.

` 4 sains-SHEET 4.

" Uivrrn srarns rmairnur orrion,

FRANCIS HDG'KINSQN", 035' EDGEQOI) PARK, PENNSYLVANIA, ASSIGNDR, BY MESNE ASSIGNMENTS,'T0 Til-IE GOLONIAL TRUST COMPANY, TRUSTEE, 0F PITTSBURGH, PENNSYLVANIA, A CBORATIN F PENNSYLVANIA..

OIL-ACTUATED VALVE MECHANISM EUR STEAM-TURBINES.

To all 'whom t may concern.

Be it known that Finnois Hooonrnson', a subject of the King of Great Britain and Ireland, and a resident of Edgewood Parka ery of fluid to the'engine in accordance with the load demand.

Another object is to produce a valve con-E trolling mechanism in which means are employed for eliminating, to a great extent, the, friction of rest between the governor controlled parts and, for overcoming the tendw ency of the valvel and the valve operating parts to stick.

Another object of the invention is to provide an oil relay actuated by speed responsive device and one which will. not be sub jected to static Ilriction but which will be extremely sensitive so to respond quick y to variations in the position of the movable member of the speed responsive device.

A further object is to produce a governor controlled valve and means for closing the valve and for rendering the governor controlled operating) mechanism incapable of opening the valve when the turbine has exceeded a predetermined speed.-

A further object is to produce a hydraulically actuated governor controlled valve op erating mechanism for fluid pressure engine, in which new and eliective means are einploycd for automatically delivering the in itial pressure motive fluid to a section or portion of the engine, nornnillf,y exposed'to, and operating under low pressure motive il uid.

These and other objects l attain by .means oi the apparatus illustrated in the acconr4 panying ,lrawings which form a part of this application.

ln the drawings accompanying this Speciication of Letters Patent.

Application led February 1G, P310. Serial No. 543,110.

plication, Figure 1 diagrammatically illustrates, by means of perspective views of the principal elements, an embodiment of my invention as applied to a steam turbine. Fig. 2 is a partial side elevation and Sectional. view of the steam chest of the turbine, equipped with a valve operating mech anism, embodying my invention. Fig. 3 is a side elevation of a steam chest shown in connection with a sectional elevation taken along the line 3-3 of Fig. 2, of the valve operating mechanism and Fig. 4 is a fragmental sectional view of the turbine, provided with a valve operating mechanism embodying my invention.

l' have illustrated an embodiment of my invention in connection with a steam turbine of the multistage type, in which a primary valve admits steam to the initial stage or section of the turbine and a secondary or overload valve byfpasses a portion of this steann'admittcd through the primary valve, around. one or more stages or sections of the turbine and admits it to a stage or section normally operating under lovver pressure.

The valye@` operating mechanism is shown as controlled by the turbine governor and is so arranged that the primary valve will open, and proportion the amount of steam Y l delivered to ythe turbine 1n accordance with. the load demand until a certain load or over-load is encountered, at which time the secondary7 gvalve willy open, the primary' -valve being Wide open, and the function. of governine, the turbine will then be shifted to the secondary valve; The secondary valve will then proportion the amount olf steam bypassed around the high pressure section and delivered to a low pressure stage or section et the turbine.

The valve operating ,mechanism shown, .consists of a reciprocating piston mounted in a cylinder to which oil, under pressure, is delivered by a governor controlled relay valve. 'ne relay valve controls the delivery of oil to the cylinder and consequently the piston moves up and down in response to variations in the speed of the turbine. A supplemental relay device is provided, and adapted to control the delivery of oil to,

and the discharge of oil from the cylinder so that the piston will move to close `both the primary and secondary valves, irrespe'itive of the operation of the governorcbntrollcd valve mechanism. This supplemental relay is shown as controlled by an emergency governor, which comes into action when the speed of the turbine has exceeded a predetermined safe speed. The oil for actuating the reciprocating piston is under pressure and may -be delivered from the lubricating system of. the turbine.

Referring to the drawings by means of the numerals which designate the separate parts, the turbine consists of a rotor element 5 and an inclosing casing 6, which is provided vvith a main fluid inlet port 7 and a secondary inlet port S. lThese ports are respectively controlled by valves 9 and 10, mounted in a steam chest 11, which is secured to the turbine casing and through which steam isdelivered to the turbine. A main admission port l2 is provided in the steam chest and -communicates with some source of high pressure steam, such as a steam generator. The valve 9 is the primary valve of the turbine and controls the delivery of steam through the inlet port 12 to the turbine. The valve 10 may be termed the secondary or overload valve and controls the delivery of steam through a by-pass 13 to the secondary inlet port 8. The passage 13 receives steam delivered by the valve 9, prior to its delivery to the port 8, and consequently steam delivered to the turbine through the secondary inlet` port 8 is bypassed around the primary or high pressure sections or stages of the turbine and is delivered to a section or stage which normally receives steam at a lower pressure.

Each valve 9 and l0 is normally held closed by a yielding agent, such for example, as' a coil vspring 14, which surrounds the valve stem and operates between a disk 16 carried bythe stein, and an adjustable spring block 17 mounted on a guide frame, shown as a bonnet 18, which is secured tothe steam. chest 1l. Both the valves 9 and 10 are controlled by a hydraulically operated piston 19, Which' is niountcd in a cylinder 20'.

to which the delivery or' oil or other liquid under pressure is controlled by a governor controlled relayA 21.

The piston 19, in reciprocating, opens and closes the valves 9 and 10 through the agency of levers 22 and 22, each of which is pivotally'connected to the piston rod 23 of the piston 19 and is fulcrumed on a separate link 24 secured to a separate stationary bracket 25 formed integrally with the guido frame 18.

The stem of the valve 9 is connected tothe operating lever 22 by means of a link 26 and the stem of the valve 10 is connected to its operating lever 22 by means of link 27 and an adjustable lost motion connection 28. The lost motion connection 28 may be so arranged that the valve 9 will be fully open and delivering a maximum amount of steam to the turbine before the valve 10 starts "to open.

The operating cylinder 20 is provided with ports 29 and 30, located at the opposite. ends of the cylinder and which respectively communicate with ports 31 and`32 of the relay 2l. A plunger is providedA with collars 34 and which form valves and control the respective ports 31 and 32. The plunger 33 is pivotally connected, by means of an adjustable link 35', with a. lever 34S, which is 'fulcrumed on the piston rod 23 and is connected to a bell-crank lever 37 by means of a link 38. The valves 34 and 353 are provided with suflicient lap to permit of a slight vibratory motion which may be communicative to them by an actuating dcvice through the .sanie'linkage which connects 'them to the speed responsive device. The actuating device is so arranged that the valves will, on account of their constant movements, become extremely sensitive, and by admitting a small amount of oil to the. cylinder 20 at cach pulsation, cause the piston 19 to slightly pulsate and be ready to respond quickly to the will of the speed re sponsive deviceand at the same time obviaul static friction which vwould be present if the valves 34 and were at any time in a posi tion of rest. "The bell-crank 37 is coi'meclcil to a similar bell-crank 371 through the me diam of a link 372. A .lever 373 is connected to a speed responsive device 37* and is pi votally supported by bracket 375. Fulcrunu-.d on the lever 373 is a lever 37 connected to a bell-crank 371 by a link 377 and to a reciprol catory rod 37B, the roller 48 of which bears upona cam surface on a Worm wheel 37 on a'shaft of the pump 4G'. The weight of tlwl rod 37S may keep the roller in Contact with the cam surface but if desired a spring may be employed for this purpose.

A. port 39 is provided in the casing of the relay 2l and is adapted to communicatewith a source ot' oil supply, such as the rotary pump 40, through a supply pipe 41.A Exhaust ports 42 are located on'each side ofthe admission port 39 and are 'adapted to communie-ate with an oil reservoir 43, through suitable piping 44. The valves 34 and 35 are so located on the plunger 33 and with reference to the ports Sl'and 32, that when one ofthe ports 3l or 32 is closed both are closed and when the one is open to the port 39 for the purpose of supplying oil pressure to the cylinder 2 0 the other is opened to one or the other of the exhaust/ports 42 for the purpose of discharging oil'from the cylinder 20. lith this arrangement, oil dclivcred to one end of thel cylinder 2O and is discharged'from the other end and the pisy ton 19 moves up or clown in response to varii communicate with the ports 39 and 42. This will deliver oil to the cylinder 20 above the piston 19 and discharge oil from the cylinder below the piston 19 and the piston will move downwardly in response to the oil `pressure to close one or both of the valves l0 and 9. As the piston 19 nieves downward in response to the oil pressure, it carries with it the ulcruni'loi the lever 36 and consequently moves'I the plunger 33 ,down and p eventually closes, the ports of the relay valve tive ports l2 and 39.

and, by confining the oil in the cylinder, temporarily holds .the piston 19 in a set position.

llhen the load on the turbine increases, the plunger 33 will be moved by the speed responsive device 37i through the communi- `eating links, to such a position that the valves 3l and 35 will place the ports Si. and 39 in communication with the respec- This will admit oil to the cylinder 20 below the piston 19 and will exhaust oil from above the piston and the piston will risc,'in response to the oil pressure, to open the valve 9 a greater or less amount, or to fully open valve 9 and then open or partially open valve i0. The continual reciprocations of the plunger 33, in response to the reciprocations of the rod 378 causes the oil pressure of the cylinder 20 to pulsate slightly at all times. This causes, suiiicient motion in the valve operating mechanism to overcome a tendency' oi the valves and the valve operatingmechanism to stick, but it may not be suiiicient to cause substantial pulsations in the steam delivered to the turbine.

During light and nhormal loads on the turbine, the piston 19 in recip1ocating,'varies the position of the valve 9 only. As the load increases and the turbine slows down a corresponding amount, the piston 13 is raised to such a position that the lost motion connection 28 becomes etlective and lifts the valve l0.

The/supplementalielay 61 is provided forA vthe purpose of closing" the valves 9 and 10 when the turbine exceeds a certain determined speed. The relay valve 61 is adapted to exhaust oil from the cylinder 2() below the piston 19 and to admit oil to the cylinder above the piston, and its ports are so proportioned that the piston 19 will move down to close both of the valves 9 and l0, irrespective of the position of `the relay valves rlhe casing' ofthe valve 61 is divided, into three chambers 62,' 63 and 64, and the chan'ibcr 54C communicates. with a source of oil supply, such as the pump 40, through a pipe .65 and with the 'upper portion of the cylinder 20 through a pipe or passage 66. ln Fig. 1, the relay valve 61 is shown as a separate valve for illustrative purposes and is connected to the cylinder 2O by means of pipes. The other drawings illustrate a preferable arrangement in which the valve casing is secured to the cylinder 20 and communicating passages are formed in the cylinder walls. A valve 67 is located in the chamber 6l and is adapted to control the communication between the oil supply pipe and thecylinder 20.

The chamber 62 communicates with the lower end of the cylinder 20 through a passage or pipe 68 and with an exhaust pipe 69, which leads to the reservoir 43. The chamber 62 incloses a valve 70 which controls the communication between the passage 68 and the exhaust pipe 69 when seated. Both of the valves 67 and 70 are coupled together and their operation is controlled by means of the piston 71, which is located,

`within the cylinder 63.

Live steam is admitted to the cylinder 63 above the piston 71 through a pipe 73. An exhaust pipe 74 communicates with the lower end of the chamber 63 below the piston 71 and is closed by means of a valve 75. The piston 7l is so constructed that it permits steam to leak around it and consequently it is balanced when the valve 75, in the exhaust pipe 711, is closed. Each of ythe valves 67 and 70 are so arranged that that are held to their seats by oil pressure, when closed. In seating the relay valve 61 the valve is rst closed so that steam pressure eoualizes on each side of the piston 71, then the piston 71 and the valves 67 and 70 are raised so as to close communication between the respective pipes or passages 65 and 66 and pipes or passages 68 and 69.

vboth the valves 67 and 70 and admitting oil pressure to the cylinder 2O above the piston 19 and discharging it from out the cylinder below the piston. The ports of the relay valve 61, as has been said, are of such size that the piston 19 will move to what 1s shown as the lower end of the cylinder 2() and close both ofthe valves 9 and 10 irrespective of the position of the-relay plungerv In reseating the relay 61 it is necessary to close the valve 75 in the exhaust 'pipe 74, set the trip lever 79 and also raise thvalves i5? and 70 and the piston 71 to an upper les 19. The emergency governor contacts with.

the trip lever only when the speed of the turbine exceeds a safe determined speed.

Having new described myinveiition, what l claim is:

l. An engine, a valve for admitting niotive fluid to said engine, a pressure actuated motor for actuating said valve, a governor controlled relay for controlling the operation of said motor andan auxiliary relay for rendering said governor controlled relay ineffective and for causing said motor to close valve.,

2. An engine, a valve for admitting motive fluid to said engine, means for actuating said valve, a governor controlled relay device for controlling the operation of said means, an emergency governor, and an auxiliary relay controlled by said emergency governor for rendering said governor controlled relay ineilective and for causing said means-to close said valve.

3. An engine, a valve for admitting inotive fluid to said engine, hydraulically actuated means for controlling the operation -of said valve, a governor controlled relay 30.

device for controlling the operation of said means, an emergency governor, and an auxiliary relay controlled by said governor for rendering said relay device ineffective and for causing said means to close said valves.

1. In combination in a turbine, a valve for delivering motive fluid to the turbine, a pressure actuated mechanism for opening and closing" said valve, a lrelay valve for controlling the operation of said mechanisni, a governor for controlling the operation of said relay valve, a connection between said relay valve and said mechanism whereby movements of said mechanism cause motion of said relay valve, and means for imparting a vibrating motion to said relay valve.

5. Iii an oil relay, a piston and its cylinder, ports leading to said cylinder, a valve for uncovering said ports, ymeans forimparting a positive opening movement to said valve, and means for imparting a constant vibratory lmotion to said valve.,

G. In an engine, a valve for admitting motive iluid to said engine, a pressure-ac-v controlled relay for controlling the operation of said motor, means for connecting the movable parts of the motor and the relay together, and an auxiliary relay for rendering said governor-controlled relay ineffective and for causing said motor to close said valve.

8. In a relay, a piston and its cylinder, ports leading to the cylinder, a valve for controlling the ports, a connection between the valve and the piston whereby movements of the piston causemovements of the valve, and means for imparting a constant vibratory motion to thefvalve.

9. In an oil relay, a piston and its cylinder, pressure delivery ports leading tothe cylinder, a valve having lap and controlling said ports, a connection between the piston and the valve whereby movements of the piston cause movements of the valve, and means for imparting a vibratory motion to the valve without fully uncovering said ports.

10. ln an oil relay, a cylinder having pressure delivery ports formed therein, a piston located within the cylinder and movable in response to variations in pressure Within the cylinder, a vibratory valve for controlling the cylinder ports, said valve being mechanically connected to the piston whereby movements of the piston cause movements of the valve.

1l. In combination in an engine, an inlet valve for delivering motive fluid to the engine, a pressure actuating motor for opening and closing said inlet valve, a governorcontrolled valve for controlling the delivery of actuating pressure to said motor, an emergency valve for delivering actuating pressure to said motor to close said linlet valve independently of the operation of the governor-controlled valve, and an emergency governor for controlling the operation of said emergency valve. l l2. In combination in a turbine, a main inlet valve for delivering motive fluid to the high pressure section of the turbine, a secondary inlet valve for delivering motive fluid to a section of the turbine normally receiving low pressure fluid, a motor for aoA tuating both of said valves, a governor driven by the turbine for controlling the operation of said motor, and emergency means for controlling the motor tc close said valves independently of, the operation of the governor.

13. In combination in a turbine, a valve` nieuwe pressure lluid to a section of tlie turbine normally receiving duid at a lovver pressure and on which the function of governing the turbine is imposed when the lirst valve is fully opened, mechanisms for controllingclose both of said valves.

14. ln a turbine, a main inlet valve 'for delivering motive duid to a high pressure section or" the turbine, a secondary inlet valve for delivering high. pressure motive -luidto a section of the turbine normallyv receiving motive fluid of a lower pressure, means for actuating said valves so that the main inlet valve is opened irst and operates to govern the speed of tbe turbine until 'the secondary valve is open, governor-controlled mechanisms for controlling the operation oi' same means, a device for rendering; said governor-controlled mechanisms inedective and `for causing said means to close both of said valves, and an emergency governor for controlling the operation of said device.

15. In combination in a turbine, a valve for delivering motive fluid to the turbine, a pressure actuated mechanism for actuating said valve, a relay valve :for controlling tbe delivery of actuating fluid to said mecha'- nism, a governorv for actuating said relay valve, means for imparting a vibratory motion to said relay valve, and means for movn ing said relay valve in response to movements of said admission valve. Y

16. In combination with an engine, an admission valve, a pressure actuated motor for actuating said valve, a governor actuated relay valve for controlling the operation of said motor, means for moving said y relay valve 1n response to movements oi said valve actuatingr motor. and means lor iur parting a constant vibratory motion to said relay valve.

17. In combination with an engine, an admission valve, a valve actuating motor for controlling the operation oli said valve, a relay valve for controlling the operation of said motor, a governor responsive to tbe speed of the engine for actuating said relay valve, means for moving said relay valve in response to motion imparted to said admission valve by said motor, and means actuated by said engine for imparting a vibratory motion to said relay valve,

'18.A In combination 'with an engine, e admission valve, f a valve actuating lmotor for controlling the operation of Asaid valve, a governor relay valve. for controlling the operation of said motor, .means for moving said relay valveiu response to movements of said motor, an emergency valve for controlling' the operation ci said motor independently of said relay valve, and an emergency governor Jfor actuating said emergency valve.

19. In combination in a turbine, a valve -for admitting motive fluid to a high pressure section thereof and for governing tbe turbine through a determined range ol speeds, a oy-pass valve ttor delivering high pressure motive liuid to a section of the turbine normally receivingl fluid at a lower pressure and on un ich the function of governing` the turbine is imposed when the lirst valve substantially Wide open, pressure actuated mechanisms Jfor controlling both valves and for opening the by-pass valve after the admission valve is substantially `ilully open, governor controlled means responsive to movements of said pressure actuated mechanisms or controlling'the operation of said mechanisms, and means for imparting a vibratory motion to the governor controlled ni i aus during,y the operation of the turbine.

20. ln combination in a turbine, a valve for admitting high pressure motive fluid to a liigb pressure section of said turbine, a second valve lor delivering motive fluid to a section of the turbine normally receiving motive fluid at a pressure less than that delivered by the admission valve, a pressure actuated motor for controlling the operam tion ol' both valves, a governor, a relay valve actuated by said governor ifor controlling the operation ci said motor, means for mov#- ing said relay valve in response to movements of said motor, and means for imparting` a vibratory motion to the relay valve during the operation of the turbine.

2l. ln combination in a turbine, an admission valve for delivering' motive luid to the turbine, a second valve i'or delivering motive 'fluid to the turbine, a pressure actuated motor for actuating both of saidgvalvcs, a

separate actuating lever between said motor and each valve, a governor actuated relay for controlling the operation of said motor, means or'impartinsj a vibratory motion to said relay during' the operation of the turbine, and a lever actuated by said motor for moving said relay.

22. ln combination in a turbine, an ad mission. valve for delivering' motive fluid to the turbine, a second Yvalve for delivern ing 'motive fluid to the turbine, a pressure actuated. motor, .connections between said motor and said valves 'whereby one of 'said valves is opened-prior to tbe openingof the other and closed subsequent to the closing ,ci the other, a relay for controlling the ment of `the motor, and means for imparting a. vibrator); motion to the relay during the operation of the turbine.

Q3. in a rela-y mechanism, a piston, a. cylinder therefor having a. port formed therein,

a valve. having 'lap cpntrolng the passage of Huid through said port, a Connection between the piston al'nd the vave whereby movements of the piston cause movements of the vave,

and means for elminatingthe effect of'the 10 lap -wth which said valve is provided.

In testimony whereof, I have hereunto subscribed my name this 8th day of Febru-

Images