US2356504A - Oil well pump and the like - Google Patents

Description

Aug. 22, 1944. R. L. CHENAULT OIL WELLPUMP AND THE LIKE Fild March 2o, 1944 2 sheets-Sheet 1 5. 6 A 4 6&4 55

N R. L. @HFQNA ULI www , Aug- 22, 1944- 4 L. cHENAl'JLT 2,356,504

\ OIL WELL PUMP AND THE LIKE Filed March 20, 1944 2 Sheets-Shed 2 xm l jIl!!4 Sym r IHN! S- XS 62 l 3mm Z RL. QHBNAULT m fb-47@ 1 the chamber in the well.V

A cur if the pump is not This 'additional head Patented A'ugjzz, 1944 i Roy nchenmut,v ou cit Research & Development Company, Pa.,'a corporation o! Delaware hPa., assign'or to Gulf), z

Pittsburgh, f n

ippucatimmwn 2o, massi-lama 527,285, e claims. (cl, 10s-24o) This invention relates to oil Wellpunipsand the like, having a displacement chamber submerged in a pool of oil in awellwhich is'altemately lle'd with oil from the pool and with ygas under pressurefrom'the top of the well, the oil in the chamber being displaced by the gas intorwell tubing for delivery to thesurface ofthe ground.

Such pumps generallyinclude two, spaced, concentrically arranged strings'of tubing located in the usual casing ofthe well;` The innerstring forms anoil eduction pipe through 'which oil from the displacement chamber is vconducted to the top of the well while the annular space be- Y tween the tubes serves as a conduit to'deliver the top of the Well to Theow of gas and oil is controlled and directed by meansA ofvalves carried by the tubing inthe wellfor alternately gas under pressure from `establishing and interrupting communication between the annular gas spaceand the displacement chamber and then, for exhausting the displacement chamber ofee trappedgas; between the displacement chamber and the well casing. 4

yHe'retofore difficulty has been encountered with pumps of this type irl the design of an eflcient yet simply constructed' and operated arrangement of valves and tubing by means offwhich full and positivejcontrol of the pumpisrobtained even under adverse conditions o'foper'ationr Ijiston, sleeve and poppet or plug'typevalves vhave been used in these pumps but have not rfold increase in head as when theinner and outer pump tubes are 'of onef'and [two-inch diameter, respectively, and may require forlifting purs posesa gas pressure farin excess of the pressure of thegas available for normal, continuous pump operation 1 l i i When"v this occurs itV is necessary to "unload the pump, i. e., reduce the head of yoil in the tube ing'to normal or to a Vweight of oil that can be raised by*- the pressure of the gasV available for Y operating'the Dump.VY Generally this 'is accomplished throughv the provision `of` automatickick' oi."valves at spaced, intervals 1 on the inner ltube string, .ThesevalvesV automatically admit pressure gas into the inner tubestring at progressivelylower levels but'th'eir use is notalways convenient, economical vior'usatisfactory. Somef Y times it may be desirable to' completely evacuate the pump of oil into the well, asbefore pulling proven altogether satisfactorybecause of ex'cessive wear and leakage, exaggerated occasionally by excessive quantities of sand in the oil, misalignment of the pump etc. Proper seating ol.'

poppet' and plug-type valves may not always -oc perfectly vertical. Also, when pumps of the above in a well, or when such as is known in the art, typeV are iirstfinstalled pumps are left idle in a well,V sometimes for even a few hours, `itmayib'e dimcult or impossible to start them.' for the reason that oil 'accumulatesfin' the well v and may, -under formation pressure, seek a level in vboth the well and the pump which isy considerably in excess of the normal, working, submergence head of the pump. Then, sinceftheoil in the pump is trapped bythe action of the'automatically closing oil inlet valve of Vthe pump, compressed ,gas-admitted, to the pump for operating it must not only raise the already abnormal head of oil in the eduction tube, but must 'also operatela'gainst an additional head V-of oill occasioned by"dis`placement offthe contents ofthe annulus vinto the eduction tube.

ofroll mayresult in athre'e- A further object-cntY thev inventiois thepio- 3'5" visionof valve means vf ordischarging' oil whichY the pump or in advance of'operationor torclear the pump of undesirable or foreignfmatter.

It is an object of the presentinvention to pro vide a pump'ofpthe character described, with an arrangement of valves and- 'tubing' such that proper seating of. the valves is achieved even under adverse conditionsof operation and Ythough the tubing may deviate slightlyfrom the vertical.

' A 4further .object of the invention is the provision of a pump of the character described which does'notr need kick-'oil valvesand which may be quickly brought into operation regardless of the.

head of oil accumulatingfvinl the f tubing 'abovev the displacement chambe accumulates in the annular gas space above the displacementchamber, directly into the we1l,fthat is, into the space in the well betweenthefwell casing and the pump,

A Yfurther object, Qfinelnvenub'n :eine prt;

visioniof means :forv discharging l oil accumulating yin' the displacementAv chamberf and inner tube i string,;as well as theoil accumulatingvin the annulus into the well, advantageously through the standjvalvefat the lower-end of the displacement chamber; whereby both the tube strings of vthe pump and the displacement Vchamber maybe entirely emptied of oil Vwhile'the pump remains in position in the well.

ply Aafncltheri with the cas A still further .object 'of the invention is the provision of balland seat valves inl a pump of the 'character described foralternately connect ing the displacement chamber with theV gas supy the valve assembly having a flow channel-therethrough for discharging oil: from the displacement chamber-into theVVV inner or'eduction tube string for removing the oil from the well.

These and other objects are accomplished by the pump..of the present invention as will be apparent from the following description and ac' companying drawings wherein,

Fig. 1 is a view partly in vertical sectionl and Fig. 3 isa detail vertical .sectional view of theV lower end of the pump including a portion oi the;

displacement chamber.

Fig. 4 is a horizontal sectional view talren alongVr on their seats thereby opening the valves and aiording communication between the passages and the interior of the countersunk portions.

Balls I5 being of larger diameter than the width of the openings Il, are constrained from lateral displacement out of the countersunk .portions through such openings and are -further constrained from upwardly escaping by means of 'spider Vlr-whichv is suitably positioned in recess I8 of coupling 9. Spider llris provided with a center bore of equal or greater diameter than bore Il and concentrically arranged with respect thereto, as shown.

Coupling Ill (Figs. 2, 5 and 6) is recessed as at I9 to receive the lower end of the valve assembly body portion and has a bore 20 equal to and concentric with bore Il.V Surrounding bore line l-I of Fig. 2 in the direction of the arrows. Fig. 5 is a horizontal sectional view taken along line 5-5 ofFlg. 2 in the direction of the'arrows, Y

Fig. 6 is a detail vertical sectionalview taken along line H of Fig, 5in the direction of the arrows, and

1 Fig. V'1 is a detail vertical sectional view offa modified form" of pump valve actuating cam.

` Referring to the drawings wherein like numerais indicate corresponding parts'throughout the several views, the completefpump assembly Vis shown in Fig. 1 and consists ofV an outer stationary stringof tubing I and areciprocatox'y inner string of tubingl 2,"the two tube strings being spaced vfrom eachother and advantageously concentrically4 arranged. YThe outer stringY of tubin'gcarries-at its lower end a valve assembly or valve chestV represented generally by the nu'- meral3,iwhich in turnhas attached to its lower end the upper end of a displacement chamber 4. The lower end of the Vdisplacement chamber is threaded internally and externally for connection respectivelyvwith the upper end of'va working l barrel 5 and, through coupling 5, with the usual pump yscreen 1, asl shown.

yThe valveV chest assembly consists of a thick walled, elongated, cylindrical body portion 3 (Figs. y2, 4 and 5), recessed and threaded at its upper end where it engages with coupling jior attachment to theend' ofthe outer tube string, and threaded at its lowerA end `for engagement with coupling III. for connection'withlthe Vupper end ofthe displacement chamber. The body portion of Vvthe` valve assembly is provided centrally 1 with.V a longitudinallyV disposed boreY orj working barrel I I paralleling which anddisposed adjacent thereto in the wou of the'V body portion abouttne central bore, are a plurality of smaller bores or' tubular uid fpassageways I2.' .Passageways I2 areV advantageously equally spaced from'V each other and arranged with their longitudinal centers nearer'to the wall of the central bore" than to the outside wall of thebody-portion.` The upper ends of passageways 'I2 are enlargedorcountersunk, 'ase shown at `-I 3, topommunicateV with vcen- `tral bore II through narrow rectangularfopenings Hand to receive valve balls I 5 which are adapted to seat on short tubular extensions or valve seats IIV threaded into'the ends of the .passageways at the bottoms of each countersin'k. Innthis position as illustrated in Fig.J 4,7`balls' I5 close the ends of the passageways and projectinto bore II,Y ina position to be moved by a'cam adapted for reciprocation in thebore asV described'hereinafter, it

being notedv thatA when the valves are closed sufficient Yclearance space -is provided between Vthe balls and the outermost sidewalls of the countersunk portions tognable the cam coclrl thejballs the coupling withthe outsideof the pump, as

shown. fT he upper ends of passageways 2| are countersunk andfprovided with ball valves 23,

the structure, dispositionk and .operation of which are substantiallyidenticalwith the ball valve and seat arrangements in the valve assembly body portion justAr described. In addition, coupling I0 isL provided withaplurality of longitudinal, open fluid passagewaysu (Figs. 5 and 6) advantageously spaced midway between passages 2|. Passages 24 provide for uninterrupted communication between the displacement chamber and Vpassages VI2 in the body portion. In this regard it should be noted that, as shown, the recess inV thev top end ofthe body portion'and the recess in the topend of coupling I0 are sumciently deep to provide open iluid spaces or chambers 25fand 25, respectively. betweenthe ends of the body portion'and the adjacent ends of the coupling members.

-As recited, the lower en'd of coupling :Ill has connected to Hit,'in screw threaded engagement, the top end of displacement chamber "4 which supports at its lower end'pump workingy barrel 5. Barrel Shasa bore 21 in axial alignment with bore II and vofthesame'or less diameter. The lower end of Ybarrel 5 is'in threaded, adjustable engagement withV a'spider-like plug 28 which is providedV with cylindrical openings 29 uniformly disposed `about' a centrally located pin 30 that projects into the barrel, 'as' shown. The plug and y the pin are secured in `adjusted position on the end'rof this barrel bymeans of vlock-nutjl. o

kInnertube string 2` consists of a plurality of strings of pipe coupled end to endv and extending down within the outer tube string to a point adjacent the valve assemblyY just described. Here it connects with atubular cam-shaped member 32 of slightly less diameter Ythan the diameter of bore Il.AV I'henloweren'td'of cam 32 `is tapered externally as' at 33 to engage balls l5when the tube stringis-lowered and lcause them to rideup ontoV the cam and assume a position in which they are cocked oil their seats to open the ends of passages I2. Internally, the lower end of cam 32 is threaded. as atV 34 to engage and support the upper end of a piston packing,"carrying tube 35 which extends through working barrel Il.

Tube* 35 is reducedl in VoutsideV diameter from a point L35 at; which `a 1 shoulder isA formed, downwardly to the end. of the tube where it is threaded externally-asatk3f|.v Slid'over, the reduced end 4 of tube 35 to Alie against shoulder 36 are alternately, piston packinggcollars 38Y and piston pack- 4is lowered before cam of coupling 43 isfa carrying tube 46.V Tube tube is reduced -string 4through, the

- ment chamber. Y YFor the a lift cylinder of usual construction,

` ing washers 39; thea-latterbeing .formed of u' leather, fabric,

Y I5 and 23 olf their seats simultaneously.,` Instead, considering the tubes 'positioned'. asfshown Vin v is shown -in raised position, cam 4| moves below andout Fig. 2,-in which the inner tube string ofV engagement with ballsv 23 when the inner-string 32 engages :with balls l5 to move them oif theirseats. f

as at 42 to actuate i cam 32 holdsballs |`5 oil-their seats. sition cam 4|`v will have passed below lballs 23 per- Y y pipe Blwill pass downwardly in 3 within theouter tube stringa Ji-position in which.

In'this DU- mitting them toy close the ends of passages 2|.

'Considering'then thatduring the time o f inst'all.-` v

ing the pump and 'connecting'it for operation the level of liquid'inthe well has risenM under formationpressure to ian" excessive height, liquid will' enter'the pump throughscreen l valve 56 into the displacement chamber'through openings 41 and `pass upwardly inthe-inner tube n string' to afheight .approximately equal -to the standing level of liquidv in the Well.v l Under such conditions, `gas admitted to the pump `through b'etweenthe,'tube'strings and'forcethe lliquid Attached tothe lower end of tube bymeans l pipe 44 which extends into the displacement chamber 4 andls joined-in turn by means of coupling 45 ywith a secondpiston working barrel 5'where it is:provided with; lateral, slotted `openings 41 immediately below which the in' diameter to form a shoulder 48 and a shortextensionl 49 threaded at its lower end. Clamped against shoulder by meansfof ball valve housing 50 is a second piston 46 extends down lintoconsisting therein through-passages i2, space v sages '24 into the displacement 'chamber Yfrom whence it'will -be'orced through openings 41 vinto the eduction tube.- However, whenvthe weight'oi the column vofoilin the' eduction tube Vbecomes ,equal to thepressure of the gas, ilow'of'liquid into the tube will cease and liquid-will notbe'ejected from'thev pump. Should .this occurjit is simply vnecessary'to lower lthe inner tube stringfuntil pin' 3|!'uft'stalitt onus seaeat'whieh umethe uquid of packing material 5I'and spacing colla`r'f52,

which piston is adapted'for sliding sealing en;

gagement in barrel 5; kValve Vhousing 50; formed .as shown, has :an inwardly extending annular flange 53 agalnst'which ball valve seat 54 is held by means ofgnipple 55. Ball 56 in housing 50 operates as acheck valve'to prevent the fluid which enters the displacement chamberand 'inner tube valve from returning to the well when gas pressurelis applied tothe Vdisplacetube string into the Y stringis moved to its extreme lowermostposition;

If desired, one maybe inserted at different levelsin the inner tlow of iluid down the inner tube string; With such valves in the line, a plurality of slugs of uid may be raised in the tube simultaneously instead of completely removing one slug before 2 may be supported in concentric relation to the eduction tube by attachmentv through a T pipe coupling 58 to a projection or packinggland 59 of only of which is shown at 60. Connected to the T is a pipe 6| for delivering pressure gas from any suitable source to the pump. The inner tube string is, of course, supported in the well and adapted to be raised and lowered to actuate the valves by attachment with the piston of the lift cylinder. g 1

In operation of the embodiment of the invention just described, the outer tube string which carries the pump cylinders well and the inner tube string, or eduction tube ywhich carries the piston and valve operating cams is next lowered andvalve assembly is lowered into position in the u 5B to` seat Vwhen Vit is'determin purpose of emptying the i contents ofthe displacement chamber and inner well, however, the inner tube y. at which time pin 3|) on plug 28 engages with ball Y v56 4through the valve andlifts it off its seat.

or more ball 'checkvalvesar` 50 tube string as shown in-Fig. 1, for preventing back f I a fragment v '32,' pressure gas, stopped byY normal upper pos'ition,

in the'. pump will be forced `by` the gas'fb'ack into tube.

Vvi.s evac:uated intolthe well V'or-'i desired it maybe raised to normal, lowered -posi ion to permit ball 'oil remaining in; thepump c bexaised.y bythe pressure of the gas available'tojoperat the pump. In normal lowered position; A'ball 'check valve 58 barrel'l passesdownwardly spacezsfanq passag' S124 t through` passages |2,

non tube through epenmgsgl'land their u'pjpast 'haustion' ofllquid f ointhe f displacement chambeii/ as recited; the eduction `tubeiis "raisedl to` n A* Y l cam *'32 vrelea'sesballs YI5 which immediately'close the ends of passages I2,

thusf'shuttingoithe now of gasto the'dis'place.-

.mentgchamben and'camj4ly Ycornes]into:engagenent'with'fb'alls 23fto lift the same'from their seats yand permitthe u *Y 'gasremaining'inlthedisf' placement chamber 22. 1 As the displacementchamber is thus relieved of pressure gas, liquid in ,the well enters the pump Y as before but immediately as it is `determined that Ythe displacement chamber is filled, inner tube 2' l isloweredto normal lower position and the liq- Y.

uid expelled' as before recited. f

.Inevent it is nothecessary or desirable to Y cam is adapted to unseat bal1s23 upon lowering of the `eduction tube' beyond its normal, working,

,lower position. In this form of the invention pin 30 maybe dispensed with so that only the liquid in the annular spacesand passages above ball valves 23 isexpelled fron the 'pump into the casing when theinner tube string is lowered to its extreme lowermost position.' Withv this arrangeand ball check.

the annular space 25 and pasj throughthe lowerend of the eduction Y yermost position'juntll all" of the' oil inthe pump that the head of @ameland-inthe. vdisplacement chamber down andY into .the educ Y v u to escape vinto the" lwellY through passages24, space 26 and passages 2| and" ment liquid is accidentally or vunnecessarily expelled from the displacement chamber. of the; pump in initiailyfevacuatng thepump of excess liquid prior to regular pumpingegpergtiom The pump. of theY present Ainvention is simple Yin construction and operation and relatively inexpensiveto manui'actureand repair.. .This applicationfis. a VVcontinuation-in-pari'. `of my applicationvSerial'No. 380,043, led February '.whatrclainiinj Y ,A 1

lk1. Apparatus for` pneumatically y pumping-liq-Y from wells4 which comprisesy an inlet for f gaseousl fluid under pressure, a-,Qdisplacement chamber adapted to be positioned inj the lqudin a well, ball ,check Vvalveineens,f or ,;v enting the j chamber of entrappedgas tothewellfa second balleheck valve means for controlling theV deliv-V .ery of gaseousiiuid from said Vinlet tosaidchairi ber, a vertieallyreciprocable eduction tube in communicationgwitl'rfthe lower parto: said chamber extending vtherefrom tothe top'of the well,

` lower end of the.displacementchaxnberis pro- Y the displacement chamber to the chest and means separate from saidvalve port sealing means and carried by the eductiontube adapted upon recipro cation to actuate said valve port sealing means for alternately. admitting pressure gas into the chamber to displaceV` liquid therefrom into the eduction tubeor delivery to the top of the well and then exhausting spent pressure gas from said chamber intothe well. w T

4. The subject matter of claim 3 whereinsaid valves'are ball checkvvalves. 1

, 5.v Apparatus for pneumaticallypumpig liquids from wells comprising spaced innei` 'and :outerstrin'gs oftubing `adapted to be positioned kin a well, said innerstring of tubing forming an eduction-tubaa displacementvchamber carried Aby the outer V,tuberstring' Iadjacent; the lower end Y thereof, vpistoni.working barrels carried by said puter tube -stri'nglabove andf below said displacementchamber," a; valved fluid Yhir-pass around said upper'working barrel forestabli'shin'g' fluid communication between the'displacement chamber and the space between the tubes above the Y working barrel, a valved passage extending from the top -ofY the A.displacement chamber through the'outside wall of the outer tube string,'ball check valve means in said passage, pistonscarried by the eduction'tubein position forsliding, sealing ven-A gagement with the walls of the piston working vided -with an extension for receiving the lower end of the eductiontube, avalve adjaentthe lower. endioi the Veduction tube, ysaid tube being Vprovided with openings in -its side .wallsin communicauopyitn V4me .lower .end of the dispiace ment, chamberabove the valve-andmeans carried byQsaid displacementfchamber extension forY opening .the valve Wh'engtheeductionv tube islowg.- Y eredtoanextreme loweroperating position.vr f; 3. An apparatus;iorfpneuniatically liftingliqr uids from wells omplisingiiler and outer strings o! tubing adapted to be PQSition-ed in,` v a well, La dlsplacementc'hamber carried byj said outer string of tubing adjacent; the. lower end thereof said inner stringof tubing .forminganeduction tube for v,delivering liquids from the chamber to the top ofthe welLQa valve chest earriedby said outer string o f tubing, anexhau'st passage-leading from the chestto thexoutside I Jffth'en;outer(stringiofiV tubing, a gas `inlet"passage iorV admitting gas.

under pressure to the chest, valve. ports and`va1ve port sealing means carried'.in said-chest ior controlling fluid new through said xhaustfarid inlet Y passages, an open 'iluid Vpassageway ljading from barrels, said bottom Vpiston and barrel closing off the lower `end of the displacement chamber, ball chebk valve means adjacent'the endof the eductionV tube belowthe chamber, said tube `being in open Vcommunication above said ball check` valve with the .bottom of said chamber, cam means above theipiston in the upper working barrel and carried bygthe eduction :tube for'operatingthe I valvedntheby-pass, a second' cammeans below the piston-inthe upper working barrel and carried by the eduction tube for operating the valve inj the passage extending fromthe top ofthe displacementehamber through the outside wall of the outer ftubestring, and means carried by the lower working barrel for openingthe ball lcheck valvein-theendof the eductiontube when the tube'is'lowered to an extremelower working'posi- 171011-v Y Y m 6. The subject matter'of claim 1- wherein additional cam'.mea ns -is provided on the eduction tube for'opening both 0f said valves simultane- Qusiy whenthe eduction tube is lowered toV an extreme lowermost operating position.

Y i ROY' L.V CHENAULT.

Images