US2380836A

US2380836A - Flow control apparatus

Info

Publication number: US2380836A
Application number: US484199A
Authority: US
Inventors: Gottlieb Manious
Original assignee: Westinghouse Electric Corp
Current assignee: CBS Corp
Priority date: 1943-04-23
Filing date: 1943-04-23
Publication date: 1945-07-31
Anticipated expiration: 1962-07-31

Description

. July 31, 1945. GOTTLIEB 2,380,836

FLOW CONTROL APPARATUS Filed April 23, 1945 5': F /6) se .55 ss a so i as I a i a0 aa e4 a r so I as iv; 45

II E WITNESSES: I INVENTOR Mnmous Go'r'n. I E B. a 7 4% BY ands,

ATTORNEY Patented July 31, 1945 um'rso sures PATENT OFFICE FLOW CONTROL APPARATUS Manions Gottliell, Philadelphia, Pa asslgnor to Westinghouse Electric Corporation, last Pittabnrgh. Pa., a corporation of Pennsylvania Application April 23, 1043, Serial No. 484,199

3. Claims. (01. 211-122) This invention relates to, valves, more particularly to an arrangement oi valves for elasticiiuid-utilirlng devices, tor example, steam or.

gas turbines, compressors, tc., and has for an .7

Conversely, an increase in output is obtained with the wideropening oithe steam admission valve. Reductlonoi throttling losses is. usuall accomp ed hrcl v d n flie first stage n v mm valvesshouldbecloscdinsequencesoastoag in limit the throttling to only the valve'that is partially open.

Thus, it is well known in steam turbine practice to provide valve structure wherein a plurality oi valves are open and closed successively to obtain better partial load eiliciency be had with a single valve, but such valvestruc tures have left much to be desired in the way oi balance. sealing when closed; manufacturing costs. etc.

Therefore. another object of the invention is to provide a novel valve structure and arrangement incorporating a pr d n e a ove mentioned desirable ieatures.

These matinee. o jects are effected by the invention as'will be apparent irom the iollowing description and claims taken in connection with the accompanying drawing, forming a part of application. in which:

The sihsle figure is a transverse sectional view showing a valve arrangement in accordance with several groups, The to eachgroup'is controlled by dnefor more "steam admission valves. Variation in the turbine output isf'fobtained by openingor closing the steam admission valves, thus varying the number of nozzle groups in service. To secure the greatest reduction in throttling losses. the steam admission valves should be automatically positioned so as to allow the proper amount 0! steam to flow to carry the load. This will be accomplished by opening or closing the steam admission valves in sequence. For example, assume that the turbin is provided with three steam admission valves which supply steam to three separate nozzle groups. at the lightest loads, onLv the first steam admission valvewill be open or partially open and will be supplying steam to the first noilzle group. As the load on the turbin increases, the governor will automatically open the nrst admission valve until it is'wide open, at" which time the throttling-losses are at a Further increase in load will cause the governor-to automatlcally partially open the second steam admission valve an amount depend upon the load. However, the fl'rst steam admission valve will remain fully open with minlmumti'imttlingoi-the steam flow through it. Further increases in load would cause tlie second valve to oper wide, at which pointminimum throttling'is obtained before the third valve opens. with the use of automatic multi-valves it is seen that the throttling occurs only on the valve which is partially open.

With decreasing loads the steam admission the invention.

Reie now to the drawing more in detail. 'thereis shown, at II. a turbine comprising a rotor and a casing i2 therefor, th latter having groups oi noasles it, It and ii for admit ting suitable elastic fluid, such as steam, to the blading ll of the rotor ll.

Bteamisadmittedtothevalvecasingfl through an inlet passage II, in which is mounted a valve cage 2! having opposed outlet ports II and ill, cooperating with valve members It and 21, respectively. iormed integral with or rigidly mounted upon a valve stem 28.

Passage It serves to conduct steam from the outlet port 24 to the first nozzle group II and a similar passage Ii conducts steam from the port ll to the second male group II.

The valve cage 22 is formed with an extension 22' including a third outlet port". with which cooperata a valve member 34, also formed integrai with, or rigidly mounted upon, the valve stem 28. Steam passing through this port It is conducted to the third group oif nozzles it by the passage 35. I

The first valve member 2' is provided with a conical suriace ll, cooperating with a sharp corner 4i, formed on the valve cage 22 at the outlet port 14, with the result that when the valve is in closed position a relatively tight seal is obtained at this point. Similarly, the second valve member 21 is provided with a sharp corner 4! cooperating with the conical seat 48 on the port-forming portion 25 of the valve cage 22, whereby tight scaling is obtained at this point also. when the valve is in closing position. It'will be noted that the second valve member 21 also includes a cylindrlcal piston portion 44 cooperating with the cylindrical bore portion 1! of the outlet port 15. thereby providing for delayed opening of the second valve 21.

The cylindrical piston valve portion ll cooperating wlth the third outlet port I! in the cage extension 22' is of such length that opening oi this port is delayed beyond the opening of the first and second valve members. Thus. it will be apparent that upon movement of the valve member toward opening position. the iirst valve member 16 will immediately open, permitting flow of steam through the passage "to the first nozzle group II. Continued movement of the valve stem in opening direction will result in successive openins of the second valve member II and the third valve member 34 for how of steam through passages Ii and II, respectively, to the second and third nozzle groups 4 and I8. r sp t vely.

It will be noted that only the first and second valve members I. and 21 are provided with the mating conical surfaces and sharp corners providing-tight seals, inasmuch as only these two valves are subject to the high pressures present in the inlet pamage ii. The third valve member II is subject only to the lower pressure existing below the second valve member 21 when the latter is open.

The valve stem 2| is provided with an enlarged balancing piston l0 above the first valve member it to balance the forces exerted against the under surface of the lowest or thirdvalve member 8!.

To provide equalized pressures against these two piston surfaces. there is formed a pressure balance passage Ii, extending from end to end oi the valve member. a

The valve member is operated in the usual manner. it having an extension or rod 51 projecting upwardly beyond the casing II and received between the ears II of the bifurcated lever It. the latter being operated, through linkage j. by suitable governor mechanism (not shown); A compression spring I. confined between shoulder l1 formed integral with. or secured rigidly to. the valverod llandtheupperendoithebushing It. serves to urge the valve rod upwardly for valve -s,seo,ese

opening when such movement is permitted by the corresponding movement oi the bifurcated end of the lever ll. Downward movement of the bifurcated end forces the valve rod downwardly to eii'ect valve closing. I While, for the sake o! simplicity and clearness, the invention has been illustrated as involving only three valve members and passages. it will be obvious that additional valve members and passages could be provided without departing from the spirit of the present invention.

While the invention has been shown in but one iorm, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof, and it is desired, therefore, that only such limitations shall be placed thereupon as are specifically set forth in the appended claims.

What is claimed is:

1. Valve mechanism comprising a valve housing having an inlet passageincluding first and second outlets; means providing a first discharge passage irom said first outlet; means providing a second discharge passage from the second outlet. said second discharge passage having a branch outlet; means providing a third discharge passage from said branch outlet; and a unitary valve structure movable between first and second limits for simultaneously controlling flow through said outlets, said valve structure comprising a stem and first, second and third valve members carried thereby and so spaced therealong that at one limit of movement of the stem they close the first, second and branch outlets, respectively, and when moved from said one limit to the other limit they successively open the three outlets.

2. Structure as specified in claim 1. wherein the first valve member is of the poppet type and the second valve member is a combination of poppet type and cylinder type, whereby the outlets from the inlet passage may be sealed bottle-tight.

3. Structure as specified in claim 1, wherein the first valve member is of the poppet type, the third valve member is of the cylinder type and the second valve member is a combination oi poppet and cylinder types.

MANIOUB GO'I'I'LJEB.