US3171630A

US3171630A - Well pump

Info

Publication number: US3171630A
Application number: US265098A
Authority: US
Inventors: Doran B Harney; Jacob W Harris; Richard C Farnham
Original assignee: Dresser Industries Inc
Current assignee: Dresser Industries Inc
Priority date: 1963-03-14
Filing date: 1963-03-14
Publication date: 1965-03-02
Anticipated expiration: 1982-03-02

Description

Mlh 2, 1965 D. B. HARNEY r-:rAL 3,171,530

WELL PUMP Filed March 14, 1965 2 Sheets-Sheet l March 2, 1965 D. B. HARNEY ETAL 3,171,630

WELL PUMP Filed March 14, 1963 2 Sheets-Sheet 2 INVENTORS Doen/v 5. 5442/1/55/ cfm-a5 MA1/4224s United States Patent O 3,171,630 WELL PUMP Doran E. Harney, Downey, Jacob W. Harris, Anaheim,

and Richard C. Farnham, Whittier, Qalif., assignprs to Dresser Industries, Enc., Dallas, Tex., a corporation or Delaware Filed Mar. i4, 1963, Ser. No. 265,096 16 Claims. (Ci. 2S3-48) This invention relates generally to fluid driven pumps, and more particularly to fluid turbine driven centrifugal type pump units for submerged, so-called bottom hole pumping operations within deep wells.

Such fluid driven turbo-pump units, to which this invention relates, employ a uid reaction turbine and a fluid reaction or centrifugal type pump means coaxially coupled together to form a single compact, minimumdiametered unit with the runners of the turbine and the impellers of the pump mounted coaxially on a common shaft. in the installation of such a pumping unit in an earth bore hole, such as an oil or water well, it' is common practice, if not a practical necessity, to suspend a unit coaxially of the well bore such that the impellers and shaft of the turbine and pump rotate about a substantially vertical axis.

Heretofore, numerous difficulties have been encountered in constructing such turbo-pump units, particularly for vertical operations as before mentioned, which would operate with satisfactory efficiency and durability under all varying pumping load requirements and conditions, particularly those encountered within the deep wells. Among such diliiculties has been that of providing suitable bearing means for rotatably supporting the axial forces in the vertical shaft resulting from the weight and from the unbalanced axial uid reaction forces imposed upon the common, rotatably mounted turbine runners and pump impellers, under varying operating conditions.

It is therefore a principal object of this invention to provide a turbo-pump unit having improved means for rotatably supporting the resultant axial thrust forces of its runners, impellers, and shaft.

It is another object of this invention to provide a means for automatically balancing out the axial thrust forces acting upon the turbine and pump impellers which act through the vertical shaft.

It is still another object of this invention to provide improved means for rotatably supporting the weight of a vertically positioned turbine and pump impeller assembly unit.

It is still another object of this invention to provide improved means for elfecting improved automatic balancing out of variable unbalanced axial thrust of the rotating members of a turbine driven centrifugal pump unit, resulting from variations in pump loading conditions.

It is a further object' of this invention to provide improved means for preventing wear and damage to the several impellers of the turbine and pump, which may result from variation in axial position thereof under varying load during pump starting and stopping intervals.

It is a still further object of this invention to provide a fluid-driven centrifugal pump unit having reduced running friction and bearing wear.

These and other objects, advantages, and features of novelty of this invention will be evident hereinafter.

In the drawings, which illustrate a preferred embodiment and mode of operation of the invention and in which like reference characters designate the same or similar parts throughout the several views:

FIGURE l is a view, partly in elevation and partly in longitudinal section, of a turbine driven pump unit assembly embodying the present invention and illustratli@ Patented lli/lar. 2, 1965 ing a manner of installation thereof in a typical oil well casing;

FIGURE 2 is an enlarged, longitudinal sectional view of the turbine driven pump unit shown in FGURE l;

FIGURE 3 is an enlarged, fragmentary cross sectional View taken on line 3-3 of FIGURE 2;

FIGURE 4 is a partial, enlarged, longitudinal sectional view of a modified form of a portion of the turbine driven pump unit shown in FIGURE l; and

FIGURE 5 is a partial, enlarged, longitudinal sectional View of still another modification of a portion of the turbine driven pump unit shown in FIGURE 2.

Referring first primarily to FIGURE l, the apparatus of the invention is shown in a typical installation in a well casing 1li having installed on the upper end thereof a typical casing head 12. Within the casing 1G and suspended from the casing head 12 upon suitable pipe or tubing 14 is a turbo-pump unit shown generally at 16 which embodies the features of the present invention. As illustrated herein, the turbo-pump unit 16 is of smaller outside diameter of the casing 10, thereby enabling it to be lowered into the casing by pipe or tubing 14 in a conventional manner, to the depth in the well from which the production fluid entering the well and contained in the lower portion of the casing is to be lifted. The upper end of the pipe or tubing 14 makes connection through the casing head 12 in conventional manner to an inlet pipe 2i), which is in turn adapted to be connected to a source of power fluid, such as oil, water, gas, or the like, which may be supplied under suitable pressure through a fluid circulating pump, now shown.

The annulus 11 between the casing 10 and pipe 14 is connected at its upper end through the casing head 12 in conventional manner to a iluid outlet pipe 22, which is in turn adapted to be connected to a suitable receiver or storage means which may include means for separating and cleaning the thus received fluid and for returning a part thereof to the before mentioned circulating pump for re-introduction under pressure through the before mentioned inlet pipe Ztl to serve as the before mentioned power uid.

The housing 18 of the turbo pump unit 16 is coupled at its lower suction inlet end at 17 through a production packer which is more or less schematically illustrated at 26, to the upper end of a downwardly extending section of conventional strainer or perforated pipe 28. Packer 26 which may be of any conventional design, but preferably capable of being set and released in the well casing by manipulation of the suspending pipe or tubing 14, such as for example a conventional slip actuated hook wall production packer, serves to separate the annular space 11a in the lower portion of the well casing into which the strainer or perforated pipe 28 extends, from the annular space in the upper portion thereof containing the turbo-pump unit 16 and suspending pipe 14.

The lower portion of the turbo-unit housing 13, indicated generally at 36, in FIGURE l contains the centrifugal pump section which receives production huid from the lower portion of the well below the packer 26 through the strainer or perforated pipe 28 and through coupling 17, and discharges the same therefrom after passing through the centrifugal pump to the exterior of the housing 18 above the packer 26 through a plurality of intermediately located, circumferentially spaced-apart discharge ports 32. The upper portion of the turbo-pump unit housing 18, indicated generally at 34 in FlGURE l, contains the turbine drive section which receives power fluid under pressure at its upper end through pipe 14 and discharges the same after passing through the several turbine sections, together with the before mentioned production fluid from the centrifugal pump section, to the same intermediately located discharge ports 32. The thus commingled fluid discharged through the ports 32 from both pump section 30 and turbine section 34 flows upwardly, as indicated by the arrows 36 and 37, through the annular space 11 within the casing to the casing head 12 and thence through the outlet pipe 22 to the storage and separating means, as hereinbefore mentioned.

Referring now primarily to FIGURE 2, the turbopump unit assembly 16 comprises the before mentioned elongated cylindrical housing 18, which -is closed at its upper end by a turbine inlet head shown generally at 40 which is formed with an exterior, upper cylindrical section 44 having an outside diameter substantially equal to that of the housing 18, an intermediate section 46 of reduced outside diameter having external threads as shown at 48, which makes good connection with corresponding internal threads 50 on the upper end of the housing 1S, and a lower downwardly extending skirted section 52 of still further reduced outside diameter. Suitable sealing means, such as an O-ring and groove as shown in 54 is provided between the inside wall surface of the housing 18 and the adjacent outside surface of the intermediate section 46 of the inlet head 40. The turbine inlet head 40 is so formed with a coaxial bore therethrough having an upper enlarged portion thereof 60 and upper intermed-iate reduced diameter section 61 a lower intermediate still further reduced diameter section 62 and a lowermost section 63 which opens into a downwardly facing cup shaped recess 68. The upper enlarged portion 68 of the bore makes screwed connection by means of threads 64 with the lower end of the suspending pipe 14. A plurality of downwardly, divergingly directed inlet passages, as shown at 70, extending through the turbine inlet head 4i), interconnect the lower end of the bore portion 66 with the upper end of an annular spaced 72 formed between the outer cylindrical surface of theldownwardly proiecting annular skirted section 52 of theinlethead 40 and the adjacent inside surface of the housing 18.

The before mentioned downwardly facing cup shaped lower end portion 68 of the bore through the inlet head 4u is formed with a lower inside cylindrical wall portion '74, the lower end of which opens out into a generally downwardly facing frusto-conical shaped cavity 76 terminating in a lower cylindrical wall portion "i8 which forms the inner side of the before mentioned skirted section 52 of the inlet head 49. A plurality of obliquely directed outlet ducts as shown at 80 circumferentially interspaced between the before mentioned passages 7l?, as shown in FIG- URES 1 and 2, extending through the turbine inlet head 4t), serves to interconnect the cavity 76 with the exterior of a turbine inlet head 40 at the upper exterior beveled end portion 82 thereof,

Seated coaxially within the bore portion 61, 62, and 63 of the turbine inlet head 4t) is a control valve assembly shown generally at 84. The control valve assembly includes a ball valve 86 which normally seats on the upper inner edge of an annular valve seat member 88 which makes press iit within the lower intermediate bore portion 82 of the inlet head 40. Press fitted at its lower end into the intermediate bore portion 61 of the inlet head 49 is a ball valve cage 90 which is closed, except for an axial outlet opening 92 through its upper end. A helical spring 94 acting under compression between the upper inner end of the housing 98 and the top of the ball valve 86 serves to press the ball valve 86 downwardly upon its before mentioned annular seat. Also press fitted within the lowermost bore section 63 is a iluted guide bushing 96 hav` ing a coaxial bore through which axially slidably extends the shank 98 of a valve plunger or push rod. Integrally formed on the upper end of the shank 98 of the valve plunger is an enlarged head 100 which normally seats on the upper end of the bushing 96 and has formed on the upper end thereof a spherical depression which fits the curvature of and makes contact with the bottom portion of the spherical surface of the ball valve 86. The lower end of the shank 98 of the valve plunger or push rod cx- CFI tends downwardly into the cup shaped recess 68 with its lower end positioned closely adjacent the upper end of the turbo-pump shaft, for a purpose hereinafter more fully described.

Seated coaxially upwardly within the lower portion of the skirted portion 52 of the turbine inlet head 40 is an annular, upper retainer body 164 having a coaxial bore 106 and formed with an outer upper end portion 163- of reduced outside diameter which extends into coupling engagement with the inside cylindrical surface 78 of the skirted section 52. An O-rfing seal and groove as shown at 110 is provided between the contiguous surfaces of the skirt portion 52 and the outer upper end portion 168. The bore 106 of the retainer body 104 has fitted therein a sleeve shaped bearing liner 112, said liner 112 having integrally formed at its upper end a radially, outwardly extending ange 114 which seats upon the annular upper end surface of the retainer body 194. The inner cylindrical surface of the bearing liner 112 is formed with a plurality of axially spaced-apart, semi-circular sectioned, inwardly facing annular grooves as shown at 116.

The pump inlet head indicated generally at 42 attached to the lower end of the housing 18 is formed with a coaxial bore therethrough having an upper threaded portion thereof with an inside diameter slightly less than the outside diameter ofthe housing 18, an intermediate bcre portion 123 or reduced inside diameter, forming thereby an upperwardly facing annular shoulder 124 and a lower bore portion 126 of still further reduced inside diameter terminating in an externally threaded connection 128. The upper bore portion 120 of the pump inlet head is provided with internal threads, with which corresponding external threads on the lower end of the housing 18 makes screwed coupled connection. An annular lock ring 138 carried on the said external threads on the lower end of the housing 18 is adapted to be screwed into jamming engagement with the upper end edge of the sleeve portion 132 surroundingthe before mentioned upper bore portion 120 of the inlet head 42 and thereby serves to lock the screw connection between the pump inlet head 42 and the lower threaded end of the housing 18 in a longitudinally adjustable position relative to one another as required to clamp several turbine and pump assemblies axially together within the housing 18, as hereinafter more fully described. Y f

Positioned within the lower end portion of 'the housing 18 and couplingly seated within the intermediate bore portion 123 of the inlet head 42 is a generally annular lower retainer body 134 formed with an upper annular portion 136 having an outside diameter slightly less than the inside diameter of the adjacent portion of the the housing 1S and with a lower annular portion 138 of reduced outside diameter relative to the upper portion 136, thereby forming at the juncture of the upper portion 136 and the lower portion 138 a downwardly facing annular shoulder 140. The lower end portion 138 makes coupling engagement within the intermediate bore section 123 of the pump inlet head 42 with the downwardly facing annular shoulder 140 thereof seated upon the before mentioned upperwardly facing annular shoulder 124. An O-ring seal and groove, as shown at 125, is provided between contiguous surface of the outside of the upper portion 136 of the retainer body 134 and the inside surface of the housing 18. A set screw 142 threaded through the wall of the pump inlet head 42 extends into engagement at its inner end with a drilled recess 144 in the lower retainer body and serves to lock said retainer body firmly seated and free of axial and rotational movement within the pump inlet head 42.

I The annular lower retainer body 134 is provided with an axial bore extending therethrough, said bore having an upper, upwardly converging, frusto-conical portion 146 A and a lower cylindrical portion 148. Supported within the lower cylindrical bore portion 148 of the lower re` tainer body 134, by means of a spider structure comprising a plurality of radially extending integrally formed web members as shown at ZtS'd, is a central, coaxially located, cylindrical shaped bearing housing R52. Press tted within the bearing housing 152 is a sleeve bushing i54 which constitutes a bearing for the lower end of the turbine and pump drive shaft i22.

Rotatably and longitudinally slidably contained within the hereinbefore described sleeve shaped bearing liner 112 contained within the upper retainer body lud is an annular shaped, combined shaft bearing and plunger or piston member d having integrally formed at its upper end a coaxial, radially outwardly extending flange member or balancing disk 56, the outside diameter of which is greater than that of the annular plunger or piston member iSd, but less than the inside diameter of the adjacent walls of the cavity 76. The peripheral, marginal portion of the balancing disk 156 is formed with a downwardly depending annular rim 1155 which normally, under non-operating conditions rests upon and is supported by the upper surface of the radially outwardly extending ange portion lid oi the bearing liner i12 and under which is formed an annular cavity l59. The upper side of the balancing disk E55 is formed with an upwardly extending, annular rim 57 which makes a relatively loose rotatable and axially slidaole lit within the lower cylindrical base portion 74 of the cup shaped cavity 63.

The annular plunger member 154 is provided with a coaxial bore therethrough, the major section lltitl of which has an inside diameter substantially greater than that of the upper most end portion 162 thereof located centrally of the balancing disk 56, thereby forming at the juncture ot such upper and lower bore sections a downwardly facing annular shoulder 164 located coaxially or" the before mentioned balancing disk 156. The upper end of the shaft )122 is formed with an upwardly extending attachment portion 166 of reduced outside diameter and carrying external threads ldd adjacent its upper end. The upper end portion of the shaft 122 extends into and is tixed within the bore loll in abutment with the before mentioned downwardly facing annular shoulder led and with the upwardly extending attachment portion M6 extending through the bore E62 oi the balancing disk E56. An annular nut llitl' threaded on the shaft threads 153 serve to retain the intergal plunger member and balancing disk 154, ld firmly attached to the upper end of the shaft 122, The plunger member ld is keyed to the shaft 122 as shown at 172.

Contained coaxially with the housing 13 between the upper annular retainer body ille and the lower annular retainer body 13d is a plurality of coaxially, superimpared turbine drive stages and centrifugal pump stages, which generally occupy the upper and lower portions of the turbo-pump unit housing indicated at 34 and Sil respectively in FIGURE l. For convenience of illustration, tlnee turbine stages, located and indicated generally at T1, T2, and T3, and three centrifugal pump stages located and indicated generally at P1, P2, and P3, have been shown and described herein. However, a greater or lesser number of such Stages in either or both turbine section and pump section may be employed, the choice being dependent upon various factors and requirements of a particular installation, such as for example the available diilerential pressure, quality and kind of driving iluid, and the pumping head, volume and kind of fluid required to be handled by the pumping unit.

Each 0f the turbine drive stages comprises in brief, with reference mainly to turbine stage T2 as being typical, a turbine stater or cover body comprising an upper, annular cover plate i742, a lower annular base plate 76 and an intermediate annular separator member E73, all preferably although not necessarily, integrally formed in a single casting. The upper cover plate, intermediate annular separator member, and base plate are held together by intervening, radially extending vanes which direct the fluid flow therearound and therethrough as is well known in the art. Between the outer marginal portion of the intermediate annular separator member 17S and the annular base plate 176 is a vaned dituser section lu which, in operation, directs the tlow of power tluid inwardly at the proper Aangle into the turbine runner, as indicated by the arrows therein. An O-ring seal and groove, as shown at 83 is provided around the periphery of each cover plate of each turbine cover body, making sealing engagement with the inside surface of the housing 1S.

Between the annular cover plate E74 and the intermediate separator member 178 is formed a radially vaned, annular passage 32 for directing the iow of power luid discharged from the preceding stage, to the dirluser section ldd, as indicated by the arrows therein. Rotatably contained within a generally cylindrical cavity formed within the diiuser section of the turbine cover body is an internally vaned turbine runner 186 of the mixed ilow type, adapted to receive power iluid radially from the dittuser section ld and discharge the same axially through the central opening of the next succeeding cover plate 17d of the next succeeding turbine cover body. The runner l86 is secured to the shaft 1.7.2 by means of a tapered locking sleeve 3.37, which is press fitted between the bore of the hub 183 of the runner ld and the exterior 4cylindrical surface of the shaft 3.22. The runner hub 13d extends outwardly into and makes a relatively free rotatable lit within the circular opening in the center of the before mentioned intermediate annular separator member lld oi' the cover body.

The turbine runner ld is formed with a coaxial, downwardly extending, axial discharge sleeve 19u which, like the hub, makes a relatively free, rotatable lit within the central, circular opening in the annular cover plate 174 of the next adjacent lower turbine Vcover body. Each of the runners is formed With an exterior, radially extending, downwardly facing, annular bearing surface as shown at IN2, adapted under certain operating conditions, as hereinafter described, to make supporting engagement with the adjacent upper surface of the before mentioned cover plate 174e of the next adjacent lower turbine cover body.

Each of the turbine stages has a construction similar or identical to that of the hereinbefore described turbine stage T2 except the iirst turbine T1, which, for convenience of manufacture, has a separate diffuser section shown at 194 which is not formed as a part of a cover body of the kind hereinbefore described, but makes couplmg engagement at its upper end as shown at 1% with an annular groove formed in the lower end of the annular retainer body 194.

I Each. of the centrifugal pump stages has a construction which 1s similar to that of the hereinbefore described turbine dr1ve stages except that the vanes of the impeller and the diffuser sections may be shaped slightly differently, as is well known in the art, to provide for the proper direction of flow of pumped fluid therethrough which is 1n general in a relative direction having a tangential com ponent opposite to that of the ilow of fluid in the turbine drive stages, such Sow in the pump stages and turbine drive stages being indicated by the several arrows in FIGURE 2. As hereinbefore mentioned, the tluid discharged from the iinal stage of the turbine drive, which 1s that leaving the discharge of the runner of turbine stage T3, and the fluid discharge from the final pumn section, which is that discharged from the impeller through the dituser section of pump stage P3, commingle within the adjacent portion of the housing t8 and are discharged directly therefrom through the ports 32 into the annular space intermediate the housing i3 and the casing Mi, and thence flow up through said annular `space to the casing head l2 and out through the outlet pipe 22, as hereinbefore mentioned.

The several turbine drive and centrifugal pump stator cage or cover body units are coaxially nested together, one upon another, and secured by indexing pins as shown at 198 against relative rotation thereof, and such cover body units are clamped together axially by means and between the upper annular retainer body 104 and the lower annular retainer body 134, which are in turn clamped together by adjustment of the coupling of the threaded connection at 128, 130 between the lower end of the housing 18 and the pump inlet head 134. The hereinbefore described lock ring 130 serves to maintain such clamping coupling adjustment.

In operation of .the hereinbefore described apparatus of the invention shown in FIGURES l and 2,\power lluid is forced under suitable pressure down the tubing or pipe 14 to the upper end of the turbine pump unit 16 where it passes through the upper enlarged bore portion 60 of the upper turbine inlet head 40 and thence .thru the Idownwardly divergingly directed inlet passages 70 into the annular space 72 within the housing 118. From the annular space 72, the power iluid ows under pressure through the first diffuser section 194 radially inwardly into the passages in the runner of the iirst turbine drive -state T1 from which it is discharged axially downwardly into passage 1182 of the cover body of the second turbine drive stage T2. From the passage 182, iluid under pressure flows around the outer edge of the separator member 178 and radially inwardly through the next diluser section 180 into the main passages of the runner of the second stage turbine drive T2. From the runner of the second stage turbine the pressure fluid is discharged axially downwardly through the discharge sleeve 19t) and thence ows radially outwardly through the adjacent passage around the next inter-mediate annular separator member and inwardly through the next diffuser section into the runner of the third turbine drive stage T3 in the same manner as herebefore described. The power lluid finally discharged from the runner of the third turbine drive stage T3 iiows outwardly through the discharge ports 32, as hereinbefore mentioned.

Production flu-id which has entered the bottom of the casing 10, flows in through the openings in the strainer pipe 28, up through the pump inlet head 42, through the bore of the lower retainer body 134 `and tills the passages within the centrifugal pump section of the housing 18. Rotation of the pump irnpellers by the tu-rbine drive then causes the production -uid to be drawn in through the strainer pipe 28 and upl into the central inlet of the imp-eller of a first pump stage P1 from which it is :discharged into the passages of the vaned cover body thereof, and thence flows around into the central inlet of the impeller of the second pump stage P2 and so on until it is discharged kfrom the third centrifugal pump stage P3 and out through the before mentioned discharge ports 32.

The power iluid discharged from lthe last stage T3 of the ttubine drive and the production lluid from the last stage P3 of the pump section com-mingle as they are discharged, as indicated by arrow 36, from the openings 32 in the housing 18 into the annular space in the casing and from there the commingled power uid and pump production iluid flows upwardly, as indicated by arrow E37, through the annular space in the casing to the casing 'head 12 and thence is discharged through the outlet pipe to the storage and sep-arating means, as hereinbefore mentioned.

Because of the axial forces acting upon the several runners of the turbine drive stages and the impellers of the centrifugal pump stages resulting from the pressure differentials and dynamic forces of the fluids flowing therethrough which are seldom if ever in exact balance with each other, the whole rotating system including the shaft 122 is usually subjected to a resultant axial force, which'tends to displace it and the rotors and impellers carried thereby axially relative to the turbine and pump cover bodies and housing. This axial force must be resisted by some means which is relatively free from friction .and wear and which will `automatically compensate ifor changes in such axial -forces which must be resisted resulting from changes in variations in pumping conditions. Such means must also automatically maintain rthe proper yaxial positioning of the shaft 122 and the impellers and runners relative to the structural members of their surrounding cover bodies, otherwise ineflicient running conditions and excessive Wear will occur and even in extreme cases possible damage or destruction of the runners and impellers may eventually result.

Usually under normal operating conditions, the resultant Aaxial force in the shaft 122 is downward r-elative to the stationary portions of the apparatus, and relatively friction free automatic compensation for this downward force is `accomplished as follows.

Suicient clearance is provided at the outer edge and along the upper portion of the runner of the iirst stage turbine drive T1 to permit pressure Huid from the rst diffuser 194 to flow under pressure between the top` of the runner and the bottom of the annular retainer body 104 and `thence into the space surrounding the drive shaft 122 at the lower end of the annular plunger member y154-. The clearance between the outside diameter of the plunger member y154iand the inside diameter of the bearing sleeve 112, which may be approximately 0.006, is sufficient to permit flow of a relatively small quantity of pressure fluid 4therethrough into the annular space 159 formed under the balancing disk 156 within the rim 158. The diiferential pressure thus established across the annular plunger 154 and the balancing disk 156 with respect to the uid pressure in the rusto-conical shaped cavity 76 and the cup shaped recess 68 tends to lift the drive shaft 122 axially upwardly sufficient to balance the otherwise unbalanced downwardly directed axial forces therein. As the balancing disk 156 is thus lifted, the lower edge of the rim 158 is raised out of sealing contact with the upper surface of the bearing ange 114, thereby permitting escape of a small quantity of pressure fluid trom the space `159 into the cavity 76 from which it is exhausted at reduced pressure through the outlet ducts Sti, thereby causing a small drop in pressure under the balancing disk `156. This action continues either until equilibrium is reached between the -iluid pressure dilferential acting upwardly on the plunger 154 and balancing disk 156 and the downward force transrnitted thereto through the shaft 122 under which conditions the lower edge of the rim 158 would iloat a short distance above and out of contact with the upper surface of the bearing flange 114, or until the plunger 154 balancing disk 156 together with the shaft 122 continues to move upwardly until the upper end of the threaded portion 168 of the shaft 122 is brought into contact with the lower end of the valve plunger shank 98. Such contact of the upper end of the shaft .122 with the lower end of the valve plunger shank 98 results in slight upward movement of the shank 98 and plunger head 160, which in turn lifts the ball valve 86 off of its annular seat 88 sufiicient to permit pressure iluid entering the upper :bore portion 60 or" the turbine inlet head 46 to iiow under pressure therefrom past the control valve 84 into the cup shaped recess 68. Since the pressure of the uid thus entering recess 68 from the pressure fluid :inlet is higher than the tluid pressure acting under the plunger 154 and balancing disk 156, the upward pressure differential thereacross is thereby reduced, whereby in effect a resultant downward force is applied to the upper, central piston `area of the balancing disk 156 as dened by the bore '74. This downward force compensates for any excess upward force acting through shaft 122, plunger 152i and ilange '.156 and is automatically regulated by the distance to which the bail valve is raised off of its annular seat 88 and the rate of leakage of such duid passed -the ilange 157 into the cavity '76, thereby establishing equilibrium between the opposing forces and resul-ting in axial positioning of the rotating system of the turbo-pump assembly in a predetermined equilibrium position.

As hereinbefore described, the presseure iluid which escapes into the cavity 76 either from below the plunger 154i or from the recess 68 passed the flange 5'7 is exhausted through the passages 80 into the annular space between the casing 1li and the pipe `14 at the upper bevel surface S2 of the turbine inlet head 4d. It has been discovered that the provision for the discharge of pressure fluid from the cavity 6d to this particular low pressure location at the upper end of the turbine inlet head is an important factor not only in the proper functioning of .the hereinbefore described balancing action, but also results in an important practical simplification of the structure of the upper end portion of the turbine pump unit. A particular advantageous feature of this arrangement is that it requires only `a simple single seal on the upper end of the housing 1d and the turbine inlet head 4d, as shown at Sii. Structural simplification and reduction in undesirable bypass leakage is thus eliminated.

Referring next primarily to FGURE 5, in which a modilied form of the axial thrust balancing features of this invention `are illustrated, the turbine inlet Ihead d@ into which the supporting pipe or tubing M makes screwed connection .at 64, and the control value assembly shown generally at S4, have a construction which is identical to that of FIGURE 2. However, the annular retainer body and balancing plunger and disk assembly have a modied form of construction as follows.

Seated -coaxially upwardly within the lower skirted portion 52 of the turbine inlet head 4t) is an annular upper retainer body ltlfia having a coaxial bore, the upper end portion 260 and .the lower :end portion 292 of which have the same inside diameter and an intermediate section 264 of which -is of reduced inside diameter relative to the end portions. The upper bore portion 260 of 4the retainer body 1Mo has fitted therein a sleeve shaped Abearing liner 2%, said liner having integrally formed at its upper end a radially outwardly extending flange 26S which seats on the annular upper end surface of the retainer `body 1Mo. The lower bore portion 292 of the retainer body 104:1 has iitted therein a sleeve shaped bearing liner 2id. The inner cylindrical surfaces of the

bearing liners

206 and 210 are formed with a plurality of axially spaced apart semi-circular sectioned inwardly facing annular grooves as shown at 2112 and 214.

Rotatably and longitudinally slidably contained within the hereinbefore described upper annular retainer body tf-ia is a combined shaft bearing and plunger member shown generally at 154e, said plunger member having integrally formed at its upper end a coaxial, radially outwardly extending flange member or balancing disk 156g, the outside diameter of which is greater than that of the annular plunger member, but less than the inside diameter of the adjacent walls of the cavity 7o. The peripheral, marginal portion of the balancing disk er! like that of the hereinbefore described balancing disk 156 in FIGURE 1 is formed with a downwardly depending annular rim 158e: which normal-ly under nonoperating conditions rests upon and is supported by the upper sur-face of the radially outwardly extending flange portion S of the bearing liner 2do. The portion of the plunger member 154:1 extending below the balancing disk 15de is formed with an upper cylindrical portion 216 rotatable and axially slidable within the bearing liner 265 and a lower cylindrical portion i8 rotatable and axially slidable Awithin the bearing sleve 210 said cylindrical portions being of substantially the same outside diameter and separated axially by an intermediate section 22d of reduced outside diameter. A downwardly facing annular piston shoulder 222 and an opposite upwardly facing annular piston shoulder 224 is thereby formed on the plunger. Slight clearances of approximately 0.006 are provided between the inside diameters of the bearing liners 2% and 2.1@ and the outside diameters of `the upper cylindrical portion 2id and the lower cylindrical portion M8, respectively, of the plunger idea. A similar clearance is provided between the intermediate bo-re portion 264 of the retainer body libia and the intermediate portion 22@ of the plunger 15a-a.

An upper annular chamber 226 of variable volume is formed between the downwardly facing annular piston shoulder 222 and the upwardly facing annular shoulder 22% in the surrounding retainer body iddo and a lower annular chamber Ztl of variable volume is likewise formed between the upwardly facing annular piston shoulder 22.4 and the downwardly facing annular shoulder 232 of the retainer body libia. The upper annular chamber 226 is vented to the annular space l72a by one or more ducts as shown at 23d and the lower annular chamber 23@ is vented by one or more ducts as shown at 236 to an annular passage groove 23d formed in an intermediate, increased outside diameter portion 240 of the retainer body lil-tu. A pair of G-r-ing seals and grooves 242 and 24d are provided in the increased diameter portion Beil adjacent upper and lower sides of the groove 233 and which make sealing engagement with the adjacent inside surface of the housing lil. One or more ducts as shown at 24d are formed through the housing 18 in such position as to communicate with the annular groove 233. One or more longitudinal passages as shown at 239 are provided for placing the annular space 72a in communication with inlet to the first stage turbine drive T1.

As hereinbefore described in connection with FIGURE l, suiicient clearance is provided at the outer edge and along the upper portion of the runner of the rst stage turbine drive T1 to permit pressure fluid from the diffuser 194 to iiow under pressure between the top of the runner and the bottom of the annular retainer body ltlda, and thencel into the space surrounding the drive shaft 122 at .the lower end of the annular plunger member iddo. As hereinbefore described, the clearance ber tween the outside diameter of the lower cylindrical portion 238 of the plunger 154e and the inside diameter of the adjacent lower bearing sleeve 2l@ is suiicient to permit flow of a relatively small quanti-ty of pressure iluid therethrough into the lower annular chamber Z3@ and thence out through the

ducts

236 and 246 to the annular space between the housing 1S and the inside of the casing it). The differential pressure thus established across the lower increased diameter portion Zig of the plunger i545; tends to lift the plunger and drive shaft 22 axially upwardly. `lower fluid which enters the annular space 72a through the passage 7@ ilows inwardly through the ducts 23d into the upper annular chamber 22,6 and thence ilo-ws through the clearance space between the upper increased diamcter por-tion 2id of the plunger ida and ythe upper bearing sleeve Edd into the annular space 59 formed under the balancing disk 156:1 within the surrounding rirn 15341. The differential pressure thus established across the upper increased diameter portion 216 of the plunger member lSiu and under the balancing disk 156g within the surrounding rim 158m The differential pressure thus established across the upper increased diameter portion 2lb of the plunger member llS/ia and under the balancing disk 1:56a also tends to lift the drive shaft 1122 axially outwardly. The sum of the before mentioned lifting forces are ordinarily suicient to balance the otherwise unbalance downward axial forces imposed upon the plunger lS/-E-cz and the balancing disk upper bear-ing sleeve 266, escape of a small quantity of pressure liuid from the space y159 under the balancing disk 156a into the cavity 76 is permitted which is in turn exhausted through the passages 80 thereby causing a small dro-p of pressure under the balancing disk 156:1. This action ordinarily continues until equilibrium is reached between the uid pressures acting upwardly on the lower and upper portions of the plunger 154a and that of the balancing disk 156a and the downward unbalanced forces transmitted thereto by the shaft 122, and under such conditions of equilibrium, the lower edge of the rim 158:1 will oat on a relatively thin film of pressure fluid a short distance above and out of contact with the upper surface of the before mentioned bearing flange 208.

In the event, the upward forces acting on the plunger 154a and balancing disk 156:1 as contributed to by the fluid pressures inV the annular chambers 226 and 230 is in excess of that necessary to resist all of the downward forces acting through the shaft 122, upward movement of the shaft 122 would then result until the upper end of the threaded portion 168 of the shaft 122 is brought into contact with the lower end of the valve plunger shank 93 resulting in the lifting of the ball valve 86 off its annular seat 88 permitting pressure fluid to enter from the upper bore port-ion 60 of the turbine inlet head 40 to liow downward past the .control valve 84 into the cup shaped recess 68 as hereinbefore described in connect-ion with the operation of the apparatus of FIGURE 2. As before described since the pressure of the iiuid thus entering the recess 68 will be higher than the fluid pressure acting under the plunger 154a and balancing disk 15651, a resulting downward force will be applied to the upper central piston area dened by the upwardly extending annular flange 157 of the balancing disk 156a. This downward force will compensate for the excess upward force acting through the shaft 122 and which will be automatically regulated by the distance to which the ball valve is raised oft" its annular seat SS thereby establishing equilibrium between the opposing axial forces, resulting in axial positioning of the rotating system of the turbine pump assembly at a satisfactory predetermined point of equilibrium.

Under some operating conditions, the resultant downward forces imposed through the shaft 122 are greater than that which can be supported by the balancing system of FIGURE 2 and under such conditions, the so-called two stage balancing system shown in FIGURE 4 has the advantage of being capable of exerting a greater upward balancing force. However, with the balancing system of FIGURE 4, which is capable of exerting such greater upward balancing forces, variations in pumping conditions are apt to cause greater variations in these forces. To guard against and take care of such greater variations in the axial forces, the control valve system S4 as employed in connection with the apparatus of FIGURE 4 is of considerable important.

Referring next primarily to the apparatus of FIGURE 4, the axial thrust balancing apparatus therein illustrated is identical to that illustrated in and hereinbefore described in connection with FIGURE 5 except the control Yconnect the bore 60h of the metal head 4Gb with the annular space 72b, and serve to connect the pipe 14 with the rst stage T1, of the turbine drive apparatus and with the balancing plunger apparatus. A plurality of obliquely directed outlet ducts as shown at 391') circumferentially interspaced between the before mentioned passages 7Gb extend through the turbine inlet head 4Gb and serve to connect the cavity 250 with the exterior of the turbine inlet head 40h at the upper exterior bevel end portion S2b in the same manner as that hereinbefore described and shown in connection with FIGURE 4.

The uppermost inner, downwardly facing end portion of the frusto-conical recess 250 is formed with a downwardly facing, at bottomed circular recess 254 in which seated a metal thrust disk 256 held in place by suitable means such as screws 258.

In operation under some conditions, where driving fluid pressure and the character and head of the fluid being pumped are subject to rapid and abrupt changes causing surges, the result and axial forces in the drive shaft 122 may be intermittently reversed, or the downwardly directed forces therein intermittently reduced such as to result in upwardly directed forces in the shaft 122 suiiicicnt to bring the upper end portion 168 of the shaft into rotating abutment with the lower surface of the thrust disk 256. UnderA such conditions, the thrust disk 256 acts temporarily as a thrust bearing.

The turbine runners and pump impellers, as heretofore conventionally designed, have had no provision for limiting the axial displacment thereof relative to their respective surrounding structure and therefore at a certain stage in the life and wear of the unit, sudden destruction of the runners and impellers occasionally resulted. Therefore, another important feature of this invention resides in forming each of the runners and impellers with an exterior, radially extending, downwardly facing annular bearing surface as shown at 192 in FIGURES 2, 3 and 4. Such bearing surface 192 acts as a seat or thrust bearing means under certain operating conditions occasionally encountered, particularly in the event excessive wear has occurred at the lower edge of

rim

158, 158a or 15S!) as illustrated in FIGURES 2, 3 or 4 respectively, or in event other clearance conditions in the balancing system change in time by reason of wear of the several parts which would permit such runners and impellers to lower into rotating Contact with the upper surfaces and edges of the central passages through the several cover plates of the several stator cages or cover bodies. Such wear apparently occurs mainly at the times when the pump is just starting or being shut down when the initial or final rotation of the runners, impellers, and shaft occur with the full weight thereof being supported by the balancing disk rim 158, 15861 or 15Sb in metal-torbnstal rotational `Contact with the bearing flange 114 or Since the power fluid as it enters the top of the turbo pump unit, is subjected to a cleaning process as hereinbefore mentioned, will be substantially free of foreign material, such as would have an abrasive effect on the various parts of the mechanism, abrasion of the turbine drive runners, bearings and particularly the hereinbefore described axial thrust balancing mechanism can be maintained at a minimum.

It is to be understood that the foregoing is illustrative only and that the invention is not limited thereby, but may include various modifications and changes made by those skilled in the art within the scope of the invention as defined in the appended claims.

We claim:

l. In a turbo-drive for installation in wells, apparatus comprising:

a housing adapted to be lowered into a well;

a turbine in said housing having runners adapted to be driven by power fluid supplied thereto;

inlet means for introducing such power fluid into said housing and drivingly to said runners;

shaft means upon which said runners are fixed for support and rotation therewith about a common axis; and means for balancing axial thrust in said shaft including:

a cylinder fixed in said housing,

plunger means fixed to said shaft and rotatable and axially slidable in said cylinder, there being clearance space between said cylinder and plunger means such as to permit a'relatively low volume of fluid flow therethrough from one end to the other end of said cylinder when va diierential fluid pressure is applied across said plunger in said cylinder,

inlet duct means in said housin interconnecting said inlet means and said one end or" said cylinder,

discharge duct means in said housing interconnecting said other end of said cylinder and a discharge zone which may be of lower pressure than said inlet means, whereby said differential fluid pressure may be applied across said plunger in said cylinder and a resultant axial balancing force thereby applied to said shaft,

andV control means, actuatable by axial displacement of said shaft from a predetermined position to vary the resistance to flow of power fluid through said inlet duct means, thereby to vary said differential fluid pressure and said resultant axial force such as to tend to restore said shaft to said predetermined axial position.

2. in a turbo-pump apparatus for installation in wells,

apparatus comprising:

a housing adapted to be'lowered into a well;

rotatable' fluid reaction means in said housing for flow of iluid therethrough;

inlet passage means for admitting fluid into said housing and to said rotatable reaction means;

discharge passage means for discharging such fluid from said rotatable reaction means and from said housing;

shaft means upon which said reaction means is fixed for support and rotation about a common axis, whereby there may be an axial thrust imparted to said shaft by said iluid upon rotation of said rotatable reaction means and said shaft;

and means for balancing said axial thrust including:

a cylinder fixed in said housing,

plunger means fixed to said shaft, and rotatable and axially slidable in said cylinder,

duct means in said housing interconnecting one of said passage means and one end portion of said cylinder, and duct means in said housing interconnecting the other of said passage means and the other end portion or" said cylinder, whereby a differential fluid pressure may be applied across said plunger in said cylinder, such as to apply an axial balancing force to said shaft,

and means, actuatable by axial displacement of said shaft in excess of a predetermined amount from a predetermined axial position relative to said cylinder means to vary the resistance of -ow of fluid in one of said duct means to vary said differential pressure and the said axial balancing force resulting therefrom such as to tend to restore said shaft to said predetermined position.

3. In a turbo-pump apparatus for installation in Wells,

apparatus comprising:

a housing adapted to be lowered into a well;

fluid reacton means in said housing for flow of fluid therethrough;

inlet passage means for admitting fluid into said housing and to said reaction means;

discharge passage means for discharging such fluid from said reaction means and from said housing;

shaft means upon which said reaction means is lixed for support and rotation about a common axis, whereby there may be an axial thrust imparted to said shaft by said fluid upon rotation of said reaction means and said shaft;

and means for balancing said axial thrust including:

a cylinder force means in said housing,

plunger force means rotatable and axially slidable in said cylinder force means;

means fixing one of said force means to saidl housing and the other of said force means to said shaft means,

duct means in said housing interconnecting one of said passage means and one end portion of said cylinder force means, and duct meansfin said housing interconnecting tne other of said passage means and the other end portion of said cylinder force means, whereby a differential fluid pressure may be applied across said plunger force means in` said cylinder, such as to apply an axial balancing forcetosaid shaft,

and means, actuatable' by axial displacement of said shaft in excess of a predetermined amount from a predetermined axial positionk relative to said cylinder means to' vary the resistance of flow of fluid in one or" said duct means to vary said differential pressure-and the resultant balancing am'al force such as to tend to restore said shaft to said predetermined position.

4. ln a turbo-pump apparatus for installation in wells,

apparatus comprising:

a housing adapted to be lowered into a well;

fluid reaction means in said housing for flow of fluid therethrough;

shaft means upon which said reaction means is xed for support and rotation about a common axis, whereby therev may be an axial thrust imparted to said shaft by said fluid upon rotation of said reaction means and said shaft;

and means for balancing said axial thrust including:

a cylinder force means in said housing,

plunger force means rotatable and axially slidablein said cylinder force means,

means fixing one of said force means to said housing and the other of said force means to shaft means,

duct means in said housing interconnecting one of said passage means and one'end portion of said cylinder force means, and duct means in said housing interconnecting the other of said passage means and the other end portion of said cylinder force means, whereby a differential fluid pressure may be applied across said plunger force means in said cylinder, such as to apply an axial balancing force to said shaft, and means', actuatable by axial displacement of said shaft from a predetermined axial position relative to said cylinder means to vary the resistance of flow of fluid in the one of said duct means which is connected to said inlet passage means to vary said differential pressure and the resultant axial balancing force such as to tend to restore said shaft to said predetermined position.

comprising:

a housing adapted to be lowered into a well;

shaft means upon which said runners are fixed for support and rotation therewith about a common generally vertical axis;

and means for balancing axial thrust in said shaft including:

a pair of separate cylinder means fixed in said housing coaxial with said shaft,

a pair of separate plunger means fixed to said shaft, one of each thereof being rotatable and axially slidable in each of said cylinder means, the clearance space between each of said cylinder means and each of said plunger means being such as to permit a relatively low volume of 4fluid flow therethrough from one end to the other end of each of said cylinder means when a differential pressure is applied across each said plunger means in said cylinder means,

inlet passage means in said housing interconnecting said inlet means and the lower ends of each of said cylinder means,

separate discharge passage means in said housing sepparately interconnecting the upper ends of each of said cylinder means and the exterior of said housing, whereby a differential uid pressure may be applied across each of said plungers in said cylinder means and a resultant axial balancing force thereby applied to said shaft, and control means, actuatable by axial displacement of said shaft from a predetermined position to vary the resistance to iiow of fluid through at least one of said discharge passage means, thereby to vary said differential fluid pressure in at least one of said cylinder means and thereby vary said resultant axial force such as to tend to restore said shaft to said predetermined axial position.

6. Apparatus according to claim 5 and control means, actuable by axial displacement of said shaft from a predetermined position to Vary the resistance to flow of fluid through at least one of said inlet passage means.

7. In a turbo-drive for installation in wells, apparatus comprising:

a housing adapted to be lowered i-nto a well;

a turbine in said housing having runners adapted to be driven by power iluid supplied thereto;

shaft means upon which said runners are xed for support and rotation therewith about a common generally vertical axis;

and means for balancing axial thrust in said shaft including:

means xed in said housing having a bore of axially stepwise varying inside diameter,

plunger means xed to said shaft and rotatable and axially movable therewith,

a pair of axially spaced apart annular piston means carried on said plunger means and having outside cylindrical surfaces which are coaxial with and axially and rotatably slidable in said bore, said bore having an intermediate section of reduced inside diameter making a sliding t with the outside of said plunger means intermediate said piston means, thereby dividing said bore into upper and lower cylinder chambers in which said piston means are rotatable and axially slidable as aforesaid,

separate inlet passage means in said housing separately interconnecting said inlet means and the lower ends of each of said cylinder chambers;

separate discharge passage means in said housing separately interconnecting the upper ends of each of said cylinder chambers and the exterior of said housing, whereby a differential uid pressure may be applied across each of said piston means in said cylinder chambers and a resultant axial balancing force thereby applied to said plunger and thence to said shaft,

and control means, responsive to axial displacement of said shaft from a predetermined position to vary the resistance to ilow of power uid through at least one of said inlet passage means, thereby to vary said diiferential fluid pressure and said resultant axial force such as to tend to restore said shaft to said predetermined axial position.

8. In a turbo-drive for installation in wells, apparatus comprising:

a housing 1adapted to be lowered into a'well;

shaft means upon which said runners are xed for support and rotation therewith about a common, generally vertical axis;

and means for balancing axial thrust in said shaft including:

a cylinder xed in said housing,

plunger means xed to said shaft and rotatable and axially slidable in said cylinder,

three axially spaced apart annular piston means carried on said plunger means, and having outside cylindrical surfaces which are coaxial with and axially and rotatably slidable in said cylinder, said cylinder having an intermediate section of reduced inside diameter making a sliding t with the outside of said plunger means intermediate a pair of said piston means, thereby dividing said cylinder into upper and lower cylinder chambers in the lower one of which one of said piston means is rotatably and axially slidable, and in the upper one of which two of said piston means is rotatably and axially slidable as aforesaid, the clearance space between each of said piston means and the bores of each of said cylinder chambers in which it slides being such as to permit a relatively low volume of fluid flow therethrough from one endto the other end thereof when diierential pressures are applied thereacross,

inlet passage means in said housing interconnecting said inlet means and the lower ends of each of said cylinder chambers,

a passage means in said housing interconnecting said inlet means and the upper end of said upper cylinder chamber,

a discharge passage means in said housing interconnecting the upper end of said lower cylinder chamber and the exterior of said housing, and a discharge passage means in said housing interconnecting the intermediate portion of said upper cylinder chamber, intermediate said two of said piston means therein and the exterior of said housing, whereby such differential uid pressures may be applied across each of said piston means in said cylinder chambers and a resultant axial force thereby applied to said shaft,

and control means, responsive to axial displacement of said shaft from a predetermined axial position relative to said housing to vary the rate of flow of power tiuid through at least one of said inlet passage means, thereby to vary the differential uid pressures across said piston means and the resultant axial force such as to tend to restore said shaft to said predetermined axial positions.

9. In a turbo-drive for installation in wells, apparatus comprising:

a housing adapted to be lowered into a well;

inlet means for introducing such power uid into said housing and drivingly to said runners;

and means for balancing axial thrust in said shaft including:

a cylinder fixed in said housing,

plunger means iixed to said shaft and rotatable and axially slidable in said cylinder,

three axially spaced apart annular piston means carried on said plunger means, and having outside cylindrical surfaces which are coaxial with and axially and rotatably slidable in said bore, said bore having an intermediate section of reduced inside diameters making a sliding lit with the outside l? of said plunger means intermediate a pair of said piston means, thereby dividing said bore into upper and lower cylinder chambers in the lower one of which one of said piston means is rotatable and axially slidable and in the upper one of which two of said piston means is rotatably and axially slidable as aforesaid, the clearance space between each of ,said piston means and the bores of each of said cylinder chambers being such as to permit a relatively -low volume of fluid iow therethrough from one end to the other end thereof, inlet passage means in said housing interconnecting said inlet means and the lower ends of each of said cylinder chambers,

a passage means in said housing interconnecting said inlet means and the upper end of the said upper cylinder chamber,

a discharge passage means in said housing interconnecting the upper end of said lower cylinder chamber and the exterior of said housing, and a discharge passage means in said housing interconnecting the intermediate portion of said upper cylinder chamber, intermediate said two of said piston means therein and the exterior of said housing, whereby differential fluid pressures may be applied across each of said piston means in said cylinder chambers and a resultant axial force thereby applied through said plunger means to said shaft,

control means, responsive to axial displacement of said shaft from a first predetermined axial position to vary the rate of flow of power fluid through one of said :inlet passage means,

and separate control means responsive to axial displacement of said shaft from a second predetermined axial position to vary the resistance to flow of fluid through one of said discharge passage means, thereby to Vary the said differential liuid pressures across said piston means and said resultant axial force such as to tend to restore said shaft to said predetermined axial positions.

l0. In a turbo-drive for installation in wells, apparatus comprising:

a housing adapted to be lowered into a weil;

inlet means for introducing such power iiuid into said housing and drivingly to said runners;

shaft means upon which said runners are fixed for support and rotation therewith about a common, generally vertical axis;

and means for balancing axial thrust in said shaft including:

a cylinder fixed in said housing,

plunger means fixed to said shaft and rotatable and axially slidable in said cylinder,

three axially spaced apart annular piston means carried on said plunger means, and having outside cylindrical surfaces which are coaxial with and axially and rotatably slidable in said bore, said bore having an intermediate section of reduced inside diameter making a sliding t with the outside of said plunger means intermediate a pair of said piston means, thereby dividing said bore into upper and lower cylinder chambers in the lower one of which one of said piston means is rotatably and axially slidable and in the upper one of which two of said piston means is rotatably and axially slidable as aforesaid, the clearance space between each of said piston means and the bores of each of said cylinder chambers being such as to permit a relatively low volume of fluid ow therethrough from one end to the other end thereof,

a passage means in said housing interconnecting said i@ inlet means and the upper end of said upper cylinder chamber,

a discharge passage means in said housing interconnecting the upper end of said lower cylinder chamber and the exterior of said housing, and a discharge passage means in said housing interconnecting the intermediate portion of said upper cylinder chamber, intermediate said two of said piston means therein and the exterior of said housing, whereby differential iiuid pressures may be applied across each of said piston means in said cylinder chambers and a resultant axial force thereby applied through said plunger means to said shaft,

control means, responsive to axial displacement of said shaft from a first predetermined axial position to vary the rate of flow of power fluid through one of said inlet passage means,

and :separate control means responsive to axial displacement of said shaft from a second predetermined axial position to vary the resistance to flow of fluid through one of said discharge passage means, thereby to vary the said differential iiuid pressures across said piston means and said resultant axial force such as to tend to restore said shaft to said predetermined axial position.

ll. In a turbo-drive for installation in wells, apparatus comprising:

a housing adapted to be lowered into a well;

a yturbine in said housing having runners adapted to be driven by power duid supplied thereto;

inlet means for introducing such power fluid into said housing and drivingly to sai-d runners;

shaft .means upon which said runners are fixed for support and rotation therewith about a common, generally vertical axis;

and means for balancing axial .thrust in said shaft including:

a cylinder bore hxed in said housing,

three axially spaced-apart, annular piston means xedly carried on said sha-ft means, coaxial with and axially and rotatably slida-ble in said bore,

means fixed relative to said housing dividing said bore into upper and lower bore chambers, one of said piston means `being contained in the lower bore chamber and .the other pair of piston means being contained in the upper bore chamber,

an annular supporting flange fixedly carried by said shaft in said upper bore chamber intermediate said pair of piston means,

an upwardly facing, inwardly extending annular supporting shoulder formed around an intermediate portion of lthe bore of said upper bore chamber normally closely adjacent the lower surface of said ange, thereby forming a relatively narrow annular clearance space therebetween and upon which said iiange is adpted to seat when said shaft is in its lowermost axial position relative to said housing,

first inlet passage means in said housing interconnecring said inlet means and the lower ends of each of said bore chambers,

second inlet passage means in said housing interconnecting said inlet means and the upper end of said upper bore chamber above the uppermost piston therein,

a first discharge pesage means in said housing interconnecting the upper end of said lower bore chamber and the exterior of said housing,

a second discharge pass-age means in said housing interconnect-ing the exterior of said housing and an intermediate portion of said upper bore chamber intermediate said pair of piston means, above said annular supporting shoulder,

and control .means responsive to axial displacement of said shaft upwardly from a given axial position relative to said housing to vary the Iresistance to flow of uid through said second inlet passage means,

the resistance to iiow of huid from .the lower end of said upper cylinder bore through the clearancespace between said ange and said supporting shoulder and thence out through said second discharge passage means variable in accordance lwith variations `of said annular clearance space between said flange and said shoulder attendant upon axial upward displacement of said shaft from its lowermost position, thereby, in operation, to vary the differential uid'pressure across said piston means and the resultant axial forces thereon such as to tend to restore said shaft to a predetermined axial position.

12. In a turbo-drive for installation in wells, apparatus comprising:

housing adapted to be lowered into a well;

a turbine in said housing having runners adapted to be driven by power uid supplied thereto;

inlet means for introducing such power Huid into said housing and drivingly to said runners;

shaft means upon which said yrunners are fixed for support and rota-tion therewith about a common axis;

and means for balancing axial thrust in said shaft including:

a cylinder iixed in said housing,

plunger means fixed to said shaft and rotatable and axially slidable in said cylinder, there being clearance space between said cylinder and plunger means such as to permit a relatively low volume of huid ow therethrough from one end to the other end of said cylinder when a difieren-tial iuid p-ressure is applied across said plunger means in said cylinder,

inlet duct means in said housing interconnecting said inlet means and said one end of said cylinder,

discharge duct means in said housing interconnecting said other end of said cylinder and a discharge zone which may be of lower pressure than said inlet means, whereby said differential fluid pressure may be applied across said plunger means in said cylinder .and a resultant axial balancing force thereby applied to said shaft,

and valve means in said housing, actuatable by axial displacement of said shaft from a predetermined axial position to vary the resist-ance in said inlet duct to ow of power fluid there-through to said one end of said cylinder, thereby to Vary said differential pressure and thereby vary said force such as to tend to restore said shaft to said predetermined axial position.

13. In a turbo-drive for installation in wells, apparatus comprising:

a housing adapted to be lowered into a well;

a turbine in said housing having runners adapted to be driven by power iuid supplied thereto;

shaft means upon which said runners are xed for support and rotation therewith about a common axis;

and means yfor balancing axial thrust in said shaft including:

a cylinder fixed in said housing,

plunger means iixed to said shaft and rotatable and axially slidable in said cylinder, there being clearance space between said cylinder and plunger means such as to permit a relatively low volume of fluid How therethrough from one end to the other end of said cylinder when a diterential iiuid pressure is applied across said plunger' means .in said cylinder,

discharge duct means in said housing interconnecting said other end of said cylinder and a discharge zone which may be of lower pressure than said inlet means, whereby said differential fluid pressure may *be applied across said plunger means in said cylinder and a resultant axial balancing force thereby applied, to said shaft,

valve means in said housing, actuatable for varying the resistance to flow of lluid `from said inlet means through said inlet duct means to said other end portion of said cylinder,

and push rod means for so actuating said valve means, said push rod means being laxially slidably positioned in said housing with one end thereof adjacent one end of said shaft for contact with and axial movement by said shaft upon axial displace-ment of said shaft in a gvien direct-ion from a predetermined position, such `as to actuate said valve to vary said resistance to flow and thereby vary the axial torce applied to said plunger means in opposition to said displacement of said shaft.

14. In a turbo-drive for installation in wells, apparatus comprising:

a housing adapted to be lowered into a well;

rotatable fluid reaction means in said housing for ow of iluid therethrough;

inlet passage means for admitting such tluid into said housing and to said reaction means;

shaft means upon which said reaction means is fixed for support and rotation therewith about a common axis;

and means yfor balancing resultant axial thrust in said shaft including:

a cylinder xed in said housing,

plunger means fixed to said shaft and rotatable and axially slidable in said cylinder, there being flow passage means from one end to the other end of said cylinder such as to permit a relatively low volume of duid iiow therethrough from one end to the other end of said cylinder when a dilerential fluid pressure is applied across said plunger means in said cylinder,

discharge duct means in said housing interconnecting said other end of said cylinder and a discharge zone which may be of a different'pressure than said inlet means whereby said differential uid pressure may be applied across said plunger in said cylinder and a resultant axial balancing force thereby applied to s-aid shaft,

and control means, ac-tuataole by axial displacement of said shaft from a predetermined position to vary the said resistance in said inlet duct to how of uid therethrough such as to vary said differential uid pressure and thereby vary said resultant axial balancing torce in such manner as to oppose such axial displacement of said shaft.

l5. In a turbo-drive for installation in wells apparatus comprising:

a housing adapted to be lowered into a well;

rotatable react-ion means in said housing for ow of iiu-id therethrough;

inlet means for admitting such fluid into said housing and to said 4reaction means;

shaft means upon which said reaction means is xed for support and rotation therewith about a common generally vertical axis;

and means for balancing resultant axial thrust in said shaft including:

a pair ot separate cylinder means fixed in said housing coaxial with said shaft,

a pair of separate plunger means xed to said shaft,

one of each :thereof being rotatable and axially slidable in each of said cylinder means, the clearance space between each of said cylinder means and each of said plunger means being such as to permit a relatively low volume of duid ow therethrough from one end to the other end of each of said cylinder means when a differential iluid pressure is applied across each said plunger means in said cylinder means,

inlet passage means in said housing interconnecting said inlet means and the loi-Wer end of one of said cylinder means, and the upper end of the other ci said cylinder means,

discharge passage means in said housing connecting the upper end of said cylinder means and the lower end of said other of said cylinder means with a discharge Zone which may be .of a different iin-id pressure than said .inlet means, whereby diil'erential fluid pressures may be applied across each of said plungers lin said cylinder means in opposite axial directions and a resultant axial balancing force be thereby applied to said shaft,

and control means responsive to axial displacement of said shaft in either axial direction from a .predetermined axial position .for varying the said differential 22 pressures thus applied across said .plungers relative to one another, thereby to Vary said resultant axial force suoh as -to tend to restore said shaft to said predetermined position.

16. Apparatus according to claim 15 -in which said control means includes Valve means in a portion of said inlet passage means to vary the ioW of fluid from said inlet pasage means to at least one of the ends of said cylinder means.

References Cited by the Examiner UNITED STATES PATENTS 808,608 12/05 Kretzschmar 10B-112 1,045,619 1l/12 Griessman et al. 103-112 1,157,873 lO/15 Jacobsen 103-112 KARL I. ALBRECHT, Primary Examiner.

XOSEPH H. BRANSON, IR., Examiner.

X UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.. 3,171 ,630 March 2, 1965 Doran B. Harney et a1. 1t 1s hereby certified that error appears 1n the above numbered patent reqllrlng oorrectlon and that the sa corrected below.

Column 17, line 4,

for "rotatable" column 18,

read rotatably line 56, for "adpted" read adapted column 19, line 6, for "means variable in acocrdance" read means being Variable in accordance Signed and sealed this 10th day of August 1965.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER A Nesting Officer Commissioner of Patents

Claims

1. IN A TURBO-DRIVE FOR INSTALLATION IN WELLS, APPARATUS COMPRISING: A HOUSING ADAPTED TO BE LOWERED INTO A WELL; A TURBINE IN SAID HOUSING HAVING RUNNERS ADAPTED TO BE DRIVEN BY POWER FLUID SUPPLIED THERETO; INLET MEANS FOR INTRODUCING SUCH POWER FLUID INTO SAID HOUSING AND DRIVELY TO SAID RUNNERS; SHAFT MEANS UPON WHICH SAID RUNNERS ARE FIXED FOR SUPPORT AND ROTATION THEREWITH ABOUT A COMMON AXIS; AND MEANS FOR BALANCING AXIAL THRUST IN SAID SHAFT INCLUDING: A CYLINDER FIXED IN SAID HOUSING, PLUNGER MEANS FIXED TO SAID SHAFT AND ROTATABLE AND AXIALLY SLIDABLE IN SAID CYLINDER, THERE BEING CLEARANCE SPACE BETWEEN SAID CYLINDER AND PLUNGER MEANS SUCH AS TO PERMIT A RELATIVELY LOW VOLUME OF FLUID FLOW THERETHROUGH FROM ONE END TO THE OTHER END OF SAID CYLINDER WHEN A DIFFERENTIAL FLUID PRESSURE IS APPLIED ACROSS SAID PLUNGER IN SAID CYLINDER,