US571010A - Steam stop-valve - Google Patents

Description

1 l l r l l l l f 1 l l l l l Atty R. an W. MGLAUGHLIN.

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R.,& W. MGLAUGHLIN. STEAM STOP VALVE.`

No. 571,010. Patented Nov. 1o, 1.896.

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Patented Nov. 10, 1896.

:Tins oo.. PHOTO-umu.. wAsmNnroN D c STEAM STOP VALVE.

R.. at W.'M0L AUGHLIN.

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6 Sheets-Sheet 4.

R. &- W. MGLAUGHLIN. STEAM STOP VALVE.

No. 571,010.4 Patented Nov. 10,.1896. l

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6 Sheets-Sheet 5. v

(No Model.)

R. 8v W. MOLAUGHLIN.

vSTEAM STOP VALVE. No. '571.010,

Patented Nov. 1o, 1896.

(No Model.) e sheets-sheet e.

R. & W. MG'LAUGHLIN. STEAM STOP VALVE.

No. 571,010. Patented 110V` 1o, 1896.

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UNITED STATES ROBERT MCLAUGHLIN STEAM STOP-VALVE.

AND IVILLIAM MCLAUGHLIN, OF PHILADELPHIA,

`PENNSYLVANIA- SPECIFICATION forming part of Letters'Patent No. 571,010, dated November 10, 1896.

ADDlication iiled July 9, 1896.

To a/ZZ whom t may concern:

Be it known that We, ROBERT MCLAUGHLIN and WILLIAM MCLAUGHLIN, of the city and county of Philadelphia, in the State of Pennsylvania, have invented a certain new and useful Improvement in Steam Stop-Valves, of which improvement the following is a speci- Iioation.

The objectof our invention is to provide simple, efficient, and reliable means for effecting, at a point more or less remote from a valve controlling the delivery of steam from a boiler to an engine or other medium of utilization, the instantaneous closure of said valve upon such sudden and abnormal reduction of pressure in the delivery-pipe leading there- `fromas would be caused by the escapev of steam in considerable volume upon a rupture of the pipe or its connections, or by a sudden and material release of load or resistance in the operation of an engine supplied with steam by said pipe.

The improvement claimed is hereinafter fully set forth.

The essential features of o ur invention generally stated, consist in a piston which is connected to a stop or throttle valve governing a steam-supply pipe leading from a steamboiler to an engine, a steam heating apparatus or other medium or means for the utili- Vzation of steam, and which is normally subject to pressure'by which it is maintained in position to hold or to permit the valve to remain open during normal conditions of operationbut upon a release of such pressure,or, equivalently, upon the application of greater opposing pressure, the valve is instantly, di-

theformer case by the opening of an outlet or valve by an operator, which outlet or valve may be one of a number located at different, desired, and determined points more or less remote from the stop-valve, whereupon the pressure on the opposite side of the piston Serial No. 598,571. (No model.)

nected to the stop-valve in opposite direction to the piston by which the valve is held open, closes said valve.

In order to prevent injury to an operator by the escape of steam from the outlet through which pressure is relievedvfrom a piston to close the stop-valve, which outlet may be afforded by breaking a'frangible tube or plate or displacing a detachable plug provided for the purpose, such tube, plate, or plug is inclosed in a pressure-tight safety-.box having a pipe leading to a proper point oi discharge, and any desired number of such safety-boxes or of pressure-release valves may be employed, being located at points Where they may be readily accessible and be operated Without exposure. to escaping steam from a rupture of the steam-pipe, which would render the stop-valve inaccessible. y The improvement thus constitutes an effective safety appliance in preventing loss of life or severe injury to engineers and firemen or others employed in the fire-room of a steam vessel or other closed boiler-compartment, by enabling the escape of steam from a ruptured steampipe to be instantly stopped by the actuation of a simple and positively-acting device at any one of a number of points located in such positions and at such distance from the stopvalve and steam-pipeas to be accessible Without contact with or injury from the escaping steam.

Our improvement is readily applicable to stop-valves of the ordinary pattern Without involving any material alteration thereof,and may also be applied for closing the main injection-valves or other sea-valves of steam vessels.

In the accompanying drawings, Figure lis a diagrammatic vertical longitudinal section IOO through a steam vessel illustrating an application of our invention; Fig. 2, a similar transverse section; Fig. 3, a similar section through a building, showing our invention applied in connection with the boilers thereof 5 Fig. 4, a vertical central section through a steam stop-valve embodying our invention; Fig. 5, a similar section taken at a right angle to Fig. 4; Fig. 6, a view, partly in elevation and partly in section, of a safety-box; Fig. 7, a similar view of a steam stop-valve illus trating a structural modification of our invention; Fig. S, a similar view of the same, taken at a right angle to Fig. 7; Fig. 9, a vertical central section through a stop-valve, illustrating a further structural modification; Fig. 10, a view, partly in elevation and partly in section, of the same, taken at a right angle to Fig. 9; Fig. 11 a front view in elevation of the safety-box of Fig. 10; Fig. 12, a front view in elevation, illustrating a modified form of safety-box; Fig. 13, a longitudinal central section through the same; Fig. 14, a view, partly in elevation and partly in Vsection, of a portion of a steam-pipe, illustrating the application of our invention with the employment of two pistons; Fig. 15, a transverse section through the same, and Fig. 16 a side view in elevation of a steam-engine with the device of Figs. 14 and 15 applied on its steam-pipe.

Referring iirst to Figs. 4, 5, and G, our invention is shown as applied in connection with a steam stop-valve,which,in and of itself, is substantially of the ordinary standard form, and is of the type known as a nonreturn valve7 the valve proper being held in open position by the pressure of the steam in the boiler and closing by its own gravity when the pressure therein falls to or near that of the atmosphere. The globular body 1 of the valve is provided with inlet and outlet passages 2 $1, having suitable lian ges for connection to a boiler and to a steam-pipe, respectively, and is closed at top by a cap 4, having a central stuiiing-box 5. Communication between the inlet and outlet passages 2 and 3 is controlled by a li-ft or puppet valve 6, which seats on a ring or bushing 7 at the inner end of the inlet-passage 2, and which is connected, by a screw-cap S, to a central stem 9, having handles 10 on its outer end. Except when held down to its seat by the screwed stem and nut hereinafter described, the valve G may be raised therefrom by the stem 9 or by steam-pressure in the inlet-passage 2. Two parallel 'columns 11 11 are screwed into the body land cap 4, and are connected at top by a yoke 12, which is held in position by nuts 13, engaging threads on the upper or outer ends of the columns. For convenience of construction the collars 14, against which the yoke bears, are made separate from the columns, which are slightly reduced in diameter at and adjacent to their outer ends to receive and hold the collars against shoulders.

A cylinder or pressure-chamber 15, having a circumferential flange 16 on its outer end and provided with a head 17 of substantially similar diameter to the flange 1G, is fitted to slide longitudinally on the columns 11, the flange 16 and head 17 being recessed to fit thereon, as indicated by dotted lines in Fig.` 4. The inner end of the cylinder 15 is closed and provided with a central tubular extension 18, which passes through the stuffing-box 5 of the valve-body and is made of such length that when the cylinder- 15 is brought to its lowest or innermost position the tubular eX- tension will abut against the screw-cap S of the valve 6 and hold the latter against its seat 7. The cylinder 15 is fitted with a properlypacked piston 19, the diameter of which is greater than that of the valve 6, and to which is fixed a tubular piston-rod 20, which passes through the tubular extension 1S and surrounds the stem 9 of the valve. The inner end of the piston-rod 2O is adapted to abut against the cap-8 of the valve, and it is made of such length that when the piston is depressed to the inner extremity of its traverse in the cylinder the piston-rod will force the valve G to and hold it on its seat.

The cylinder 15 may be raised and lowered and held in any determined position on the columns 11 in order to hold the valve 6 closed when required or to limit, as desired', the maximum elevation of the valve from its seat. For this purpose the head 17, which is bolted to the cylinder, is provided with a tubular stem 21, which surrounds the valvestem 9 and is externally screw-threaded, its thread engaging a nut 22, which is fitted to rotate in the yoke 12 and is connected to a hand-wheel By rotation of the handwheel in one or the other direction the cylinder maybe raised or lowered, as desired, and is held in adjusted position by the engagement of the stem 21 and nut 22.

rlhe piston 19 is normally held at the outer extremity of its traverse in the cylinder by being subjected when in such position to the pressure of steam from the boiler upon a greater area on its inner than on its outer side. The piston is made a differential one,

IOO

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in this instance, by forming a projecting ring '24 on its outer face, which ring is finished and fits truly against a corresponding 1inished annular face 25 on the inner side of the head 17. Pressure on the outer side of the piston therefore acts only on the smaller annular surface thereof surrounding the ring 24 when the piston is at the outer extremity of its traverse, While pressure on the inner side of the piston acts upon the materially larger area surrounding the tubular pistonrod 20. Te do not, however,- limit ourselves to a differential piston of the above specific construction, and hereinafter describe another form by which the same result is equiva lently attained.

Steam from the boiler is supplied to the cylinder 15 on opposite sides of its piston 19 bya pipe or pipes 26,A a'single pipe with proper connections being in this case employed, and communication with the cylinder being effected through telescoping pipes -in order to admit of the longitudinal movement of the cylinder on the columns Without permitting the escape of steam. The pipe 26 leads into a chamber 27, formed in the yoke 12, and a pipe 28, iiXed to the cylinderchambers 27 and 29 in the movements of thecylinder and thus maintain communication between the same and the chambers irrespective of the position or condition of movement or rest ofthe cylinder.

The chamber 29 may communicate either directly or indirectly with .the pipe 26 or com-` municate directly with the boiler by an inde- In the instanceV showniu Fig. a branch pipe 3l is leadpfrom the boiler-supply pipe 2G into a chamber 33,-

pendent pipe, as preferred.

in the lower part of Which it opensby'a contracted nozzle 32. A partition 3,4, in which are formed openings orperforations having an aggregate transverse area substantially equal to or somewhat greater than that of the pipe 30, is iiXed in the chamber 33 above theV nozzle 32, and a pipe is led from the chamber 33 above the partition 34 to the chamber 29. Steam -from the boiler passes through the pipes 26 and 2S to the outer side of the piston 19 and through the pipes 26 and 31, chamber 33, and pipes 35 and 30 to the inner side of said piston, a free discharge being admitted from the inner side, When required,by ,the perforations in the partition 34.

The release of pressure from the inner orlower side of the piston 19 is effected, Whenever the closure of the valve 6 is desired to be made by said piston, by opening an outlet from a release-pressure pipe 36, communicating with the chamber 33 and through said chamber and the pipes 35 and 30 With the cylinder 15 on the inner side of the piston 19.

. The release-pressure pipe 36 is led to any desired point or points (which may be more or less remote from the stop-valve) at which itD may be deemed advisable or necessary to provide means for closing the stop-valve, and `at each of said .points it communicates With a discharge-pipe 37, leading to the atmosphere, to the condenser, or to any other safe and convenient point of discharge. The releasepressure pipe and discharge-pipe communicate either through a connecting-pi pe 38, governed by a release-valve 39, or through a normally-closed passage having a frangible or detachable member. 40, which may be a glass tube, as shown in Figs. 5 and 6, a disk, as shown in Fig. 10, or a detachable plug, as

shown in Fig. 13.

varying' or releasing devices, that is to say, a valve-governed pipe and a pipe having a frangible or detachable member, may be applied at each point of desired actuation, the special object of the latter device bein-g to provide a` means of release which can be actuated With quickness and certainty by unskilled persons, Who in an emergency might not be able to properly operate a valve. The frangible or detachable member 40 is preferably inclosed in a pressure-tight safety-box 41 in order to prevent the operator from being scalded by the escaping steam, and is broken or detached, as the case may be, by striking a slight blow upon a head 42, fixed Both of these pressure.

upona pin 43, the opposite end of Which abuts against the frangible or detachable member 40. Upon the"breakage or detachment of said member an outlet is immediately opened, through which pressure on the inner side of the piston 19 is releasedthrough the pipes 36 and 37 and their connections, and the pressure on the outer side of the piston thereupon depresses said piston and closes the valve 6.

Asshown in Figs. 1 and 2, the pressure varying or releasing devices may belocat'ed in various positions in a steam vessel, as in the engine-room, fire-room, pilot-house, and different points on the several decks. Fig. 3

shows the releasing devices in the engineroom, fire-room, and each of the different stories of a building. `It will also be seen from these figures that by connecting the IOO pressure-release pipes of the stop-valves cfa'V battery or set of boilers the simultaneous closure of the stop-valves of all the boilers Will be effected. l

The construction shownv in Figs. 7 and 8 operates similarly to that shown in Figs. 4, 5, and 6, and above described, and differs therefrom only in the form of the differential pis- IIO ton 19, which in this case is that of a frustum Y of a cone, the pressure-chamber, which corresponds, in function and relation to other members, with the cylinder 15, before described corresponding in form with the piston.

VThe piston 19 is provided with expansible packing-rin gs 45, Which iit in circumferential grooves in the piston, andare maintained in contact with the surface of the pressurechamber by steam, Which is admitted behind them from the space above the piston through passages 44, leadinginto the packingring grooves. By the contactof theexp'ansible packing-rings 45 With the pressure-chamber, which is thus maintained in all positions of the piston, it is made dierential, and, as in the instance first described, subjected, when in normal position, to pressure upon a larger area on its inner than on its outer'side. The pipe connections employed in this construction may be similar to those shown in Fig. 5, and before described.

In the moditicationshown in Figs. 9 and 10 the piston 19 is, as in the preceding instance,

normally subject to an excess of pressure on its inner side, by which it is maintained at the outer limit of its traverse. The inward stroke of the piston, by which the closure of thevalve G is'effected, is, however, in this case produced? by the admission of steam tovthe cylinder 15011 the outer side of the piston?, in:- stead of by its release therefrom, as in the preceding instances, and the outward pressure ony the piston is afforded by'a spring; The cylinder l5 is open at its inner end, and is provided with legs or standards, which are bol-ted to the cap 4L ofv the valve-body l. A short stem iis formed on or iiXed to the lower side of the valve 6, and moves in a guide 4&7, fixed.inthe'inl'et-passage 2. A piston-rodlZtS,

secured to the piston 1.9,. passes through the stuffing-box 5 ot the valve-body, and is connected at. its lower end to the Valve 6r. A helical sprirngi, which surrounds-th'evpistonrod 48, abuts against the inner sidfevor the pistony 1395 and again-st a stop fixed toY the inner end of the cylinder, the" tensionof said spring being such as toy normally hold the pistonA at the outer limit of its traverse, in which position the connected valve 6 will be fullyopen; Toy enable the valve- 6 to bey closed or itslift limitedl whenL and as recpii-red,v a stem 50 passes through a stuffing-box in the cylinder-- head i7 and a-liuts.y against the piston when at the outer limit ot itstraverse, sai-d stem bcingthreaded toenlgage a nu'tiir they-oke 12, Which,-A in. this case, isXed to ther cylinder, and carrying a hand-Wheel 5l.. Bly the rotationr of the hand-whecl the piston and con-- nected valve 6 may be pressed downward until theV valye is brought to its seat, orfor such shorter distance as' will limit the lift of the valve to any desired degree.

Theprcssure-supplypipe 26 l'ead'sfrom the boiler into the outer end of the cylindeuanda safety-box -LO is interposed between two/ sections ofsaid pipe. Communication between the sections-vof pipe on. opposite sidesof the safety-box is normally cut oit by a fran-giblel member i0', which in this instance is in the form of a plate or disk closing a port or passage-way throughthe safety-box. rEhe plateiO may be broken by a blow on the head' 42 of a pin 413 which passes into the safety-box and abuts against the plate 40. Upon the fracture of the plate l0 steam is admitted tothe outer sideot the pi'ston'19,and,by its pressure thereon-,forces the pis-ton downwardly and seats the connected valve 6, as in the instances before described.

Figs.` I2an'd 13 show a form of safety-box in` whichcommunication. is established between the release-pressure pipe 3G and dischargepipe 37 to release the pressure from the innerk side of ther piston, in the constructions ot `Figs. 4,5, 7 and 8, by displacing a detachable member having the form of a plug 40, which closes the opening of the'pipe 36 tothe safetyboX 4l. The plug 40 normally rests on= a block 53, which is preferably provided with an elastic bearing, and which may be adj usted' tov through the pipe 55tothe engine.

y hold the plug properly in= position by a setscrew The detachment of the plu-g is effected, when immediate closure of the stopvalve is desired, by' striking' a slight blow on the head 42 of the pin ifiwhich abuts against thepllug 40, and pressurev is thereby released from the inner side of thepiston through the pipes 36 andy 37, as before described.

Figs. M, 15, and? I6l illustrate our invention as applied to effect the closure of a valye 57, controlling the steam-supply pipe 55 of a steam-engine56, so asto immediately and a-utomatically shut off the supply ots-team'y tothe engine in the even-t of asudden and abnormal d-ecrease'of the load ofthe latter, and thereby prevent the damage resultant upon the engin-es "runningaway which-'isli-ableto occur in such case'. `theclosure or' the val-vey in the event of the The-construction will'al-so eftect bursting of the` steam-pipe onv the side of the valve toward th-'eengin-e'. Thlevalve 5-7, which is of the butterfly type, isjfournalcd transversely to the steam-pipe 55, and a doublearm'cd'lever59is ii-Xedi ontheproj'ecti'ng end of one et its journals. A cylinder 15, providedE with pis-terr 1.9", is journ-al'edf to the steam-- pipe onone side of the' axis of the va'llve 57, and a cylinder l5, otl smaller diameter andv fitted with a piston l0, is journaled to@ they steam-pipe ony the opposite side of the axisofl the valve. The piston-rod 48 of thecylinder l5 is coupled to on'eot the arms oi the lever 5.9,

andi the piston-rod iS-f of thesmaller cylinder 15a is coupled' tothe other arm of said lever.

Steam from the'boil'er isfsupplied tothe cylinder 15S-by a pipe 26, and` the cylinder l5 is connccted by a pipe58with thesteam-pi-pe 55at a point near the engine. The pipes-26 and' 58` aremadc sufficiently iifexibl'eor are so-j ointed as to: permitfot thev vibration of the cylinders l5 and l5fiupon'their'pivotsor trun=nions-,wheir required, without leakage of steam.v

The pressure of the steam upon the piston- 19 of the cylinder' 15isnormally greater than that upon the piston ofthe: cylinder 152, ow-

ing to the larger'are'a of the former', andi forces the piston 19 to the outer limit of its traverse, iin-whichl position it holds the connected valve-:517 openIandl permitsa free iiow oty steam VVheir, however, the pressure in the steam-pipe'on the side of the valve nearer tothe engine is suddenly and materially reduced, as by anl abnormalincrease inthe speed ot the engine orby the burstingot thepipe, the-thenlgreater pressure iny the pipe 267 acting'on the piston- '19 ot the' cylinder 15a, moves saidpiston outwardly against the diminished resistance of' the pressure on the piston 19' and immesuppl-y of steam to-the engine or to the ruptured portionof thesteam-pipe, as the case may be.

l'. The combinationK of avaflve for controlling the iifow of Huid througha pipe, tWopi's- IOO IIO

ldiatel'y closes the valve 57, shutting off the tons Which are normally and coincidently subl ject to pressure upon unequal areas respectively, rods connected to said pistons and adapted to impart the differential pressures acting thereon, in opposite directions, to said Valve, and means for applying a preponderance of pressure to the smaller piston area.

2. The combination of a valve for controlling the iiow of fluid through a pipe, a piston which is normally subject to unequal pressures on opposite sides, a rod connected to said piston and adapted to impart pressure to said Valve, a normally-closed pipe through which a variation of the degree of pressure on one side of said piston may be effected, and a,

frangible or detachable member for opening communication through said pipe.

3. The combination of a valve for controlling the flow of iiuid through a pipe, a piston which is normally subject to unequal pressures on opposite sides, a rod connected to said piston and adapted to impart pressure to said Valve, a normally-closed pipe through which a Variation of pressure on one side of said piston may be effected, a frangible or detachable member for openin g communication through said pipe, and a pressure-tight safety-box inclosing said frangible or detachable member.

4. The combination of a valve for controlling the loW of iiuid through a pipe, a piston which is normally subject to unequal pressures on opposite sides, a rod connected to said piston and adapted to impart pressure to said Valve, a normally-closed pipe through which a variation of the degree of pressure on oneside of said piston may be effected, and a series of frangible or detachable members for opening communication through said pipe at any one of a number of points variously located relatively to the valve.

5. The combination of a Valve for controlling the ow of fluid through a pipe, a differential-piston mechanism, Which normally permits the valve to remain open, and means for effecting the closure of the valve by said differential-piston mechanism by changing the direction of preponderance` of pressure thereon.

6. The combination of a Valve for controlling the flow of fluid through a pipe, a cylinder or pressure-chamber fitted to traverse toward and from said Valve on guides on the body or casing thereof, a differential piston iitting said pressure-chamber and held normally by pressure therein in position to permit the valve to be open, a rod on said differential piston extending into the Valvebody and adapted to impart pressure to the valve, pipes for the supply of fluid under pressure to opposite sides of said differential piston, and means for releasing pressure from the larger area of said diiferential piston.

ROBERT MoLAUGl-ILIN. NVILLIAM MCLAUGl-ILIN.

Witnesses as to Robt. McLaughlin:

J. SNOWDEN BELL, T. J. HOGAN.

Witnesses as no Wm. iviCLaughnn:

JAMES MOLAUGHLIN, G. A. SCHWAB.

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