US2687742A - Valve apparatus for steam control valves - Google Patents

Description

1954 R. R. CROOKSTON 2,687,742

VALVE APPARATUS FOR STEAM CONTROL VALVES Filed Oct. 11, 1952 /AllWlQ INVENTOR Robert R. Cr'ooksfon,

Patented Aug. 31, 1954 VALVE APPARATUS FOR STEAM'CONTROL VALVES RobertR, Crookston, Houston, Tex., assignor, by

mesne assignments,,to Standard Oil-Developmentflompany, Elizabeth,.N. J., a corporation of Delaware .Amllicatiomflctober 11, 1952, Serial No. 314,-380 6 Claims. (Cl. 137 -415) The-1 present invention is] directed: to; an auto matic pump or vent valve for a steam control valve. More particularly, the, inventionis directed to apparatus for use lwith a dualrseated steamcontrol valve. Inyita more particular asp cts; the invention .1 is: directed it to .a cembinationof a pilot. valveiand apoppet u valve. I

The presentinvention may bebriefly described asra valve apparatus .fona steam; control valve which comprisesa housing: attached to a steam control valve. anddefinings therewith. a first chamber. The;housingiisprovided withan ex.- haustu port in a wall fthereot andthas. a second chamber; and a piston ;cylincler. spatially removed from the second chamber. Apassageway in the housing communicates the, second chamber lwith the piston cylinder the latter of. which is vented to the atmosphere... Arranged. in the housing} and ,particularly'inmthe second chamber is. .aipilot. valve. communicating when open. the second chamber, with the; first. chamber. An'. actuating, button is arranged in the, steam control valve and. is adapted ,to be actuated thereby, V the actuating button protrud ng. into the first chamber and being attachedto thepilot valve. Aafiuid con: nection meanS such as a conduit, connects the second chamber with. an inlet to th steam con-. trol valve, A poppet valve is arranged in the exhaustport of the steam c'ontrolvalve .and communicates the first chamberwith the steam control valve. Arranged in the piston cylinder is a piston which is adaptednormally to hold the poppet valve in a closed position. The piston is-norma-lly urged-toward the piston head or in a downwardposition by firstgbiasing means and the poppet valve-is normally urged'ina closed position bya secondbiasing means'onmovement of the piston downwardly;

Thepresent inventionwillbe-further described by-reference to the drawing-in which the single figure is a sectional view of a steam control valve with the improvedvalveof the. present invention attached thereto.

Referring now to! the-drawing, numeral H designates a dual-z-seated steam control valve provided with an-inlet l2 and an-outlet13l Inlet l 2 and". outlet l 3 =communicatabya central =passageway M Lin which. isarranged: a seating cage I52 The inlet 12, for -example,-maybeconnected tola. steam pipeleading: to steam= generation equipmentxand cthe outlet F3 may-be connected to a steam engine or a steam pump andrthe-Jike.

Themage. l5zzis providedrwith: valve t seats l6 and: hasiarrangediz therein a: valve-:seating memher I?! i provided wi hw seatina surfaces l 8; and. I 9: he sea i m mb r lldsrrnrovidedwith anlexe tension member I 8a which serves to actuate a:

pilot valve actuating button aslwillabe described.

22 provided with packing 23 and valve bonnet 24. Thecover plate 2| is-attached to the valve housing II by means of bolts 25 andnuts 25. The valve stem 20 is provided with threads 21 which extend. through an. internally threaded: sleeve 28 in bonnet24. The. valvestem 20 is providedwith means suchasa lever armor hand Wheel29 for rotating the valvestem Zil ion lifting and lowering the: seating member I].

The-lower portionof the valve; housing H. has attached to it a housing 30 which. defineswith a wall of the valve Ill a first. chamber. 3|. The housing 30. also isprovided withasecondchamr ber 32. and a piston cylinder, 33;. The piston-cylinder 3.3 and. the second-chamber 32 communicate by. a. passageway. 34. and orifice-35,. in acap nut. 36 which serves to close. the piston cylinder 33. The cap 36, is provided with a, vent. 31.

The second chamber 32 is alsow enclosedby. a. cap nut 38. The second chamber 3'2jcommunicates with the. inlet [2 by way of. passageway 39. in the valve ll to which is threadably connected a connection 40 which isprovided with an orifice member 4|. The connection 4E3 connects to a conduit 42 which may be a copper tubing which, in turn, connectsby Way ofa connection means 43 with a passageway 44' in the housing 30which communicates with the chamber 32 Protrudinginto the central passageway I4 is an actuating button 45 which engages with. a, valve stem 46 arranged in thefirst chamber 31 and,

in turn, connecting to the valve member 4"! in chamber--32. The actuating button 45 passes through a packing; gland 48 threaded into the valve housing II which seals theactuating button 45-by packing 49*which is heldin place with the packing g1and48:

The valve stem 46 is provided with-a plate or shoulder 50 and the valve stem" 46 is slidably arranged in" a sleeve memberbl which is provided with a passageway 52 which servesto communicate the chamber 3! with chamber 32- on opening'of the valve-1i"! aswill be described;

The sleeve 51 has an outwardly projecting shoulder 53:: bearing against a lowerend of a The plateor= shoulder 5!] acts as a restrainingxmeans for the uppenend helical coil spring 3'51:

OfithQCOi-l spring :5 4.:

Arranged in thepiston cylinder-2331B a piston 55! 55: The r piston 15:5: is provided zW-ithz a. valve stem coil spring 6 l.

55 to which is attached a poppet valve member 51. The poppet valve member 51 is arranged in an exhaust port 58 of the valve II and the exhaust port 58 is provided with an annular seating member 59 which is threada'bly engaged with the valve II. The annular seating member 59 encloses the poppet valve 51 and is provided with an upwardly projecting inner sleeve til which serves to limit the downward travel of the poppet valve 51. Surrounding the sleeve i! and bearing against the annular member 59 and against the poppet valve member 51 is a helical Springs 62 and 53 bear against the lower outer surface of the annular member 59 and against an inner surface of the piston 55; helical coil springs 62 and 63 normally serve to urge the piston 55 downwardly.

The housing '30 defines an exhaust port 55 through which the exhaust steam may be vented.

The piston 55 is sealed in the cylinder 33 by means of steam packing 65.

It Will be noted that the valve stem may be adjusted bythe slotted screw member 66, cap 38 being removed for this purpose.

The valve 51 is designed to seat on seat or member 61.

The present invention operates in the following manner:

When the extension member Ilia is lowered by the valve stem being rotated to close the valve I! by the seating member l1 seating on surfaces [6, the member i800 strikes the actuating button 45 and causes the valve 41 to be unseated. Meanwhile steam is flowing into the inlet l2 and into central passageway l4. Since dual-seated valves 1 have some leakage there is steam pressure being exerted against the poppet valve 51. Also steam pressure is being exerted through the passageway 39, the conduit 42, passageway 44, chamber 32, passageway 34 and through orifice against the piston 55 which holds the valve stem 56 and valve 51 upwardly in seating engagement with annular Seating member 59. As the actuating member 45, however, is moved downwardly the valve 41 moves off of the seat 61 and causes steam to pass through the passageway 52 into the chamber 3| and through the exhaust port 64. This causes equalization of pressure on both sides of the poppet valve 51 and the piston 55 is biased downwardly by springs '52 and 53 leaving only the spring 6| to hold the poppet valve 51 in a closed position. Thus a small pressure build up in central passageway l4 due to leakage of steam past the seating surfaces I8 and I9 will allow the pressure on poppet valve 51 to overcome the spring Bi and to cause the exhaust from passageway 14 into chamber 3| to pass to exhaust port 64.

In my apparatus it is desirable to have the orifice 4| larger than the vent 31. For example, the orifice 41 may be 0.04 inch in diameter, whereas the vent 31 may be 0.03 inch in diameter. Thus a small amount of steam is bled out through the vent 31 but pressure may build up against the piston 55 and hold the valve 51 in a closed position. It is to be noted that since the pressure in central passageway I4 may be greater thanin piston cylinder 33 due to theventing of a small amount of steam through vent 31 the area of the piston 55 is greater than the area of poppet valve 51 allowing a lower pressure of steam than the pressure of steam in central passageway It to hold the poppet valve 51 closed.

It is also to be noted that in the travel of the extension member 18a the device of my invention is active only during the last few thousandth inch of travel (0.005 inch). This distance may be adjusted by taking up on the set screw 66. Thus the forces resisting the actuating button 45 may not amount to over 40 or 50 pounds total.

One advantage of the valve of the present invention is that the poppet valve pops open all the way. Any tendency of the steam engine connected to the valve to coast due to leakage into the steam chest is arrested by the fact that the valve stem 55 is forced back by the springs Bi and 52 and by a suction created in the central passageway 54 by passage of steam to the outlet 93 so that engine braking may be realized as if no. dump valve at all were used allowing the apparatus of the present invention to serve a dual purpose.

By virtue of the orifice 4i being greater than vent 31, for example 0.04 and 0.03 inch steam pressure builds up below the piston 55 to overcome the springs 62 and 53 as well as the unit steam pressure delivered multiplied by the area of the poppet valve 51, which is one square inch, thus holding the valve closed.

As a specific example of a valve in accordance with thepresent invention, the springs 62 and 63 may have a total compression of about 200 pounds. The piston 55 may have an area of 1% square inches; therefore, the springs E52 and 63 will move the piston and permit opening of the valve 5? at any condition in the valve H less than pounds per square inch gauge. With the orifice H and 31 having diameters of 0.04 and 0.03 inch, respectively, and a travel of 0.005 inch on valve '41 the pressure maintained may be about.

50 pounds per square inch gauge.

The present invention. has numerous advantages. 'In dual-seated steam control valves, such as employed in oil Well steam drilling rigs, it is not only desirable but imperative at times to stop the steam. engine completely. Since the dualseated valves have a tendency to leak, the steam engine may suddenly move due to accumulation in its steam chest due to steam leakage past the control valve seats. Thus tongs, rotary tables and spinning chains actuated by the catheads may suddenly be energized causing loss of limb and life of personnel exposed to such hazards. In my invention there is no danger of the steam leakage allowing the engine to be operated since my valve automatically will cause any accumulation of steam leakage past the valve seats to be exhausted.

Valve 51 also serves as acheck valve in instances where a rapidly moving lightly loaded engine is stopped quickly. Spring 6! holds valve 51 in light contact so the engine cannot suck in air" and thus coast too long. Sprin 0| and valve 51 are so proportioned that a positive pressure of /2 p. s. i. will open valve 51 in spite of the spring 6 i.

While my apparatus is shown to have coil springs E52 and 63 biasing piston 55 downwardly, I contemplate that the coil springs 52 and 63 may be replaced by a single coil spring. Likewise, .while the valve apparatus of the present invention is shown attached to a particular type of dual-seated valve, I contemplate that it may be attached to and form part of any dual-seated valve provided with an extension member, such as extension member 18a to actuate the actuat ing button 45.

The nature and objects of the present invention having been completely described and illustrated, what I wish to claim as new and useful and to secure by Letters Patent is:

zieevgmz i 1. Valve apparatusfiifori'an:engines andpump control steam valveewhich tcomprises ,1 in combination}: ashousing attacheditoca steam control valve defining withiaiwall of the steamlcontrol valve a first chamber; said housing defining an :exhaust port with aflwall thereofrand saidhousing being provided with. asecond chamber: and: a piston said steam control valve, a piston arranged in said piston cylinder. adapted normally to hold said poppet valve in a closed position, first biasing means normally urging said piston downwardly, and second biasing means normally urging said poppet valve into a closed position on movement of said piston downwardly.

2. Valve apparatus for an engine and pump control steam valve which comprises, in combination, a housing attached to a steam control valve defining with a wall of the steam control valve a first chamber, said housing defining an exhaust port with a wall thereof and said housing being provided with a second chamber and a piston cylinder spatially removed from said second chamber having a vent in a wall of said housing and a passageway communicating the second chamber with the piston cylinder, a pilot valve arranged in said housing communicating when open the second chamber with the first chamber, an actuating button arranged on the steam control valve and adapted to be actuated thereby protruding into the first chamber and operatively connected to said pilot valve, a conduit connecting said second chamber with an inlet to said steam control valve, a poppet valve arranged in an exhaust port of said steam control valve, a

piston arranged in said piston cylinder adapted normally to hold said poppet valve in a closed position having an efiective working area greate than an effective working area of the poppet valve, first biasing means normally urging said piston downwardly, and second biasing means normally urging said poppet valve into a closed position on movement of said piston downwardly.

3. Valve apparatus for an engine and pump control steam valve which comprises, in combination, a housing attached to a steam control valve defining with a wall of the steam control valve a first chamber, said housing defining an exhaust port with a Wall thereof and said housing being provided with a second chamber and a piston cylinder spatially removed from said secondchamber having a vent in a wall of said housing and a passageway communicating the second chamber with the piston cylinder, a pilot valve arranged in said second chamber communicating when open the second chamber with the first chamber, an actuating button arranged on the steam control valve and adapted to be actuated thereby protruding into the first chamber, a valve stem operatively connected to said button and to said pilot valve, a conduit connecting said second chamber with an inlet to said steam control valve defining a restricted passageway having an area of flow greater than an area of flow of the vent in the piston cylinder, a poppet valve ar- 6; ranged in an exhaust: port of said steam": control valve; a-r piston arranged in said ipi-stont cylinder adapted normally to :hold E saidi poppet valve, in i a closed position' l'iavin'g an eifectiveworking area greater than an effective working; area of the poppet valve, a first coil spring normally eurging saidpiston downwardly; andasecond coil spring normally: urging said i poppet- :valve into a closed position onunovementof said piston downwardly; 4 Valve apparatus forwan engine and 1 pump control-steam valve whicli comprises, in combination; a housing attached to a steam: control valve defining with a-"wall of thesteam'control valve a first chamber; said" housing defining an exhaust- 'port with a wall tliereof i and said housing being provided" witli a secondchamber and a piston cylinder spatially removed from said second chamber and a passageway communicating the second chamber with the piston cylinder, a cap nut connected to said housing to enclose said piston cylinder provided witha vent, a second cap nut connected to said housing to enclose said second chamber, a pilot valve arranged in said second chamber communicating when open the second chamber with the first chamber, an actu ating button arranged on the steam control valve and adapted to be actuated thereby protruding into the first chamber, a valve stem operatively connected to said button and to said pilot valve, a conduit connecting said second chamber with an inlet to said steam control valve defining a restricted passageway having an area of flow greater than an area of flow of the vent in the piston cylinder, a poppet valve arranged in an exhaust port of said steam control valve, a piston arranged in said piston cylinder adapted normally to hold said poppet valve in a closed position having an effective working area greater than an effective working area of the poppet valve, first coil spring normally urging said piston downwardly, and a second coil spring normally urging said poppet valve into a closed position on movement of said piston downwardly.

5. Valve apparatus for an, engine and pump control steam valve which comprises, in combination, a housing attached to a steam control valve defining with a wall of the steam control valve a first chamber, said housing defining an exhaust port with a wall thereof and said housing being provided with a second chamber and a piston cylinder spatially removed from said second chamher and a passageway communicating the second chamber with the piston cylinder, a cap nut connected to said housing to enclose said piston cylinder provided with a vent, a second cap nut connected to said housing to enclose said second chamber, a pilot valve arranged in said second chamber communicating when open the second chamber with the first chamber, an actuating button arranged on the steam control valve and adapted to be actuated thereby protruding into the first chamber, a valve stem operatively connected to said button and to said pilot valve, a coil spring surrounding said valve stem normally urging said button upwardly to close said pilot valve, a conduit connecting said second chamber with an inlet to said steam control valve defining a restricted passageway having an area of fiow greater than an area of flow of the vent in the piston cylinder, a poppet valve arranged in an exhaust port of said steam control valve, a piston arranged in said piston cylinder adaptednormally to hold said poppet valve in a closed position having an efifective working area greater than an effective working area of the poppet valve, a first coil spring normally urging said piston downwardly, and a second coil spring normally urging said poppet valve into a closed'position on movement of said piston downwardly.

. 6. Valve apparatus for an engine and pump control steam valve which comprises, in combination, a housing attached to a steam control valve, said housing being provided with an exhaust port and a piston cylinder having a vent in said housing, a pilot valve arranged in said housing, means fiuidly communicating said piston cylinder with an inlet to said steam control valve, said pilot valve communicating when open the fluid communicating means with said housing exhaust port, actuating means arranged on the steam control valve and adapted to be actuated thereby protruding into the housing and operatively connected to the pilot valve, valve means arranged in an exhaust port of said steam control valve, a piston arranged in said piston cylinder adapted normally to hold said valve means in a closed position, first biasing means normally urging said piston downwardly, and second biasing means normally urging said valve means into a closed position on movement of said piston downwardly.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,291,609 Nichols Jan. 14, 1919 2,481,265 Van Denberg Sept. 6, 1949

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