US 2720266 A
Description (OCR text may contain errors)
Oct. 11, 1955 LINE INSERTING DEVICE FOR HIGH PRESSURE VESSELS Filed Oct. 5, 1953 D- E. BROUSSARD ET AL 2 Sheets-Sheet l lnven'ors: D. E.. Broussard H. E. Mc Knnzg Bg- H. 7n c Thzir ATTornckj Oct. 11, 1955 D. EBROUSSARD ET AL 2,720,266
LINE INSERTING DEVICE FOR HIGH PRESSURE vEssELs Filed Oct. 5, 1953 2 Sheets-Sheet 2 lnven'ors: D. E. Brousse r-d Fg H. E. Mc Kinnzg Bx): H` 714 Thair Ai'i'orng United States Patent O LINE INSERTING DEVICE FOR HIGH PRESSURE VESSELS Douglas E. Broussard and Howard E. McKinney, Beliaire,
Tex.,tassignors to Shell Development Company, Emeryville, Calif., a corporation` of Delaware Application OctoberS, 1953, Serial No. 384,021
Claims. (Cl. 166-77) This invention relates` to oil well equipment and pertains more particularly to an apparatus for inserting strings of flexible, elongatedycylindrical elements, such as cables, wire lines, etc.,` through a pressure seal into a high pressure vessel.
Since the present invention is especially well suited for inserting strings of flexible cable into high pressure wells, it will be described herein in its application to this particular type of operation, the closed well being considered as a pressure vessel. It is, however, understood that the invention is in no way limited thereto, but may also be used for inserting temperatureiand pressure bulbs or similar instruments, and leads and connections appertaining thereto into pressure vessels such, for example, as reaction chambers or towers inoil refineries, etc.
lt is often desirable during the operation of a high pressure well to. introduce thereinto on a line or cable various well tools or instruments such as gun perforators, logging electrodes, pressure or temperature recorders, flow indicators, etc. Insertion of these devices into the well casing or tubing is generally accomplished by placing the instrument attached to the cable into a lubricaton which consists of a length of pipe placed above the master valve on the christmas tree, or on a wellhead, said' pipe having a sealing element,` stuliing box, or other suitable closure means at the top thereof. With the master valve closed, the lubricator is connected to the wellhead,` the sealing element or stuffing box is` closed: about the cable secured to the tool, the master valve` is opened, and the tool lowered into the well.
In order to overcome the force exerted by the well pressure acting on the cross sectional area of the cable which tendsto force the cable out of the well` and sometimes reaches very high values,` it is generally necessary to4 attach weights or sinkers to the lower end of the cable either below or above the tool. When a very small-diameter wire line or cable is used, tools can be successfully introduced into a low pressure well by this means. However, when tools are` to be introduced into a high pressure well, it is not practical in most cases to use a sufficient amount of sinkers to overcome the well pressure andthe friction of the sealing element or stuting box on the cable.
A cable-injecting device which has been successfully employed inV inserting cables or wire lines into high pressure wells is described inl detail in our copending application, Ser. No. 209,546, led February 6, 1951, now U. S. 2,677,427 of which this invention is an improvement. While the cable-injecting device described in said patent can be used satisfactorily on high pressure wells, diiculty is experienced at times when certain types of cables or wire lines, especially those of small diameter, are to be inserted in high pressure wells, the main diculty being a lack of suicient frictional contact between a Wire line and the single-groove sheaveof the above-identified cableinjecting device to operate satisfactorily on high pressure wells.
It has been found that the frictional pull of a sheave on a wire line in a cable-injecting device may b e con- 2,720,266 Patented Oct. 11,1955
siderably increased by employing aV sheave which` has` a wide groove and winding the cable or wireline around-the sheave several times. While attaining the desired result of obtaining the greater frictional contact between the wire line and the sheave, this is only :accomplished with several attendant disadvantages. For example, the. necessarily nearly dat-bottomed groove of the-sheave tends to flatten the round cable and cause excessive' tlexing and wear of the steel wires making up the cable, and: thus, shortens the life of the cable. Additionally, aA widegrooved sheave does not possess the high friction'ali contact with a cable which may be realized by a sheave having rounded V type grooves in it, whichexhibits aiwedging effect on a wire line, if the wire line is of slightly greater diameter than the bottom of the groove. The greatest disadvantage of having several continuous wraps-of cable on a wide-grooved sheave is that the design of the groove causes the cable to slide axially on the sheave: as the cable is moved into or out of a well. This sliding contact between the sheave and the cable causesl rapid wear on the surface of the cable, especially when the cable issubjected to considerable tension as, for example, during.` its use in a high pressure well.
it is, therefore, a primary object of the present invention to provide an apparatus for inserting a line` or cable through a sealingv element into a high pressure well without the necessity of usingweights or sinkers;
lt is also an object of this invention toprovide ai device of the above type comprising a housing of toroidalor annular shape, said shape enabling said housingtor enclose a relatively large diameter wheel and withstand high internal pressures without undue increase of the thickness of itsv walls.
A further object of this inventionis to provide a cable# gripping mechanism adapted to grip a substantial length` of a` cable while passing it through` ahigh pressure sealy and insertingr it into a well` casing or tubing.
Another object of this invention is to provide` er cableinjecting device employing a multi-grooved sheave, the' multiple grooves of said sheave providing azlarge area for frictional contact with a cable while at the same time'l minimizing any wear or deformation of said cable;
Another object of this invention is tot provide af cable!-V injecting device employing a multi-groove sheave, the multiple grooves of said sheave allowing several partialwraps of thefcable to pass over the sheave, thereby greatly increasing the pulling capacity of the sheave with a minimum of wear and deformation of the cable.
Other objects and advantages will be apparent from the following description taken in reference to the drawings, wherein:
Figure 1 is a front elevation, partly in cross-section, of the present cable-inserting mechanism.
Figure 2 is a cross-sectional view of the cable-gripping element of the present apparatus taken along the line 2-2 of Figure 1. Y
Figure 3` is a bottom View of the multi-grooved cabledriving sheave and the guide or transfer rollers of the present cable-injecting device. p
Figure 4 is an isometric view of a multi-grooved driving wheel having transfer or guide rollers positioned therebelow, diagrammatically illustrating the operating principle of the present invention.
Figure 5 is an enlarged cross-sectional view of three wraps of cable positioned in the cable grooves of a portion of the cable-driving wheel or sheave shown in Figure 3.
Figure 6 is a cross-sectional view of a modied form of the cable driving sheave and driving mechanism therefor.
Referring to Figure 1 of the drawing, the cable-injecting device of the present invention is provided with a circular housing 12 designed to withstand the high pressures encountered in oil wells. As shown in Figures 1 and 2, the central part of said housing 12 comprises a plate 13 having holes 14 therethrough for mounting the apparatus in any suitable manner above a wellhead. In the outer portion of the housing 12 an annular pressure-tight charnber or passageway 15 is formed within concentric walls 16 and 17, sidewall 18 and an annular cover plate 19, said cover plate 19 having internally' threaded flanges 21 and 22 adapted to lit the threaded cooperating surfaces of the concentric walls 16 and 17 as shown in Figure 2. To assure a lluidtight seal, packing rings 23 and 24 may be used if desired.
Since the ability of the walls of a pressure vessel to withstand internal pressures is a function of the shortest unsupported length or dimension of said walls, it will be seen that the annular shape of the pressure space 15 within the present housing 12 has the advantage of permitting very high pressures to be used in said space without the walls having to be made excessively thick. It may be readily shown that if said pressure housing were given a'cylindrical or spherical shape instead of an annular shape, the thickness of the walls thereof would have to be increased by a considerable factor in order to be able to withstand the same pressures.
The inner concentric wall 17 of the housing 12 forms a journal bearing or shaft. Slidably mounted for rotation on the periphery or outer surface 25 (Figure 2) of the inner concentric wall or bearing 17 is a gear wheel or ring gear 26 having a gear track 27 cut in approximately onehalf of the width of its outer surface and a plurality of circumferential grooves 28 cut in the other half of said surface.
' The circumferential grooves 28 are adapted to receive and substantially contain therein several wraps, or a con siderable length, of a cable 30 insertable through a lubricator 31 into a well casing or tubing (not shown). Since lubrcators are well known to the art and form no part of this invention, they will not be described in further detail at this time. The size of the grooved wheel 26 and the size of the grooves 28 therein are necessarily dependent upon the flexibility of the Vcable 30 and the size thereof, respectively. As shown in Figure 2, the grooves 28 are preferably of a depth equal to at least one-half of the diameter of the cable 30 contained therein. When the cross-sectional diameter of the grooves 28 is equal to the diameter-ofthe cable 30, equal frictional forces will be applied between the surface of said grooves and the lower half of said cable 30 when the gear ring 26 is rotated.
In certain cases it is desirable to provide grooves which exert a gripping action on a cable contained therein. Excellent results have been obtained by employing a ring gear 26a (Figure 5) having a groove 28a slightly smaller in diameter than the normal cable diameter and having a depth equal to about three-fourths of the diameter of the cable 30. In order to get the cable 30 in the smaller groove 28a, it is necessary to open up the top of the groove by beveling the walls'thereof at anangle depending on the difference in the diameters of the cable and groove. A groove 28a of the above-described design does not crush the cable excessively and exerts a gripping action on the cable 30 whereby greater frictional force may be applied between the groove and the cable than when a groove and cable of equal diameter are used.
The diameter of the grooved ring gear 26 depends upon the flexibility of the cable 30 being inserted in the well, said flexibility being in turn dependent upon the size and Cil material and type of construction of which the cable is made. Note that the ring gear and grooved sheave may be bolted together to allow easy replacement of one part or the other. Normally, the diameter of the ring gear 26 is from about twenty to fifty times or more than the diameter of the cable 30. If an armored or insulated conductor cable is employed having an outer armored sheath of a plurality of wires twisted around the cable, the diameter of a ring gear to be used with this cable should be about two hundred times or more the diameter of the wires in the outer armor.
The large diameter ring gear 26 which is rotatably mounted on bearing 17 is adapted to be rotated by a relatively small diameter pinion 32. A suitable stuing box 33 is provided around the shaft 34 of the pinion 32 to form a lluidtight seal therearound. The shaft 34 of the pinion 32 is operatively connected to and rotated by a suitable prime mover means (not shown), for example, a hydraulic, pneumatic or electric motor. If desired, the drive shaft 34 of the pinion 32 may be provided with means such as a clutch 35 for disengaging the pinion 32 from its prime mover means (not shown) whenever it is not necessary to force the cable 30 into the well, or whenever it is not necessary to hold or brake the cable from being extruded from the well by the well pressure. For example, when the weight of an instrument (not shown) being lowered in the well and the weight of the cable 30 inserted into the well is suicient to overcome the pressure extruding forces, the driving pinion 32 or the drive shaft 34 may be disengaged so as to allow the driving gear wheel 26 to turn more freely on bearing 17.
If desired the driving pinion 32 and drive shaft 34 may be provided with a suitable Ashifting means which can be used to shift the pinion from its meshing contact with the driven gear 27 Whenever it is not necessary to either drive or to brake the driving sheave 26, see Figure 6. For example, the driveshaft 34 might be provided with a thrust collar 63 which is positioned by a positioning sleeve such as the threaded sleeve 62. Thus the sleeve 62 could be turned from outside the housing to disengage the pinion from the mating gear inside the housing. The driving wheel 26 would then idle freely without turning either the pinion 32 or its drive shaft 34. This has the obvious advantage of eliminating the frictional drag of the rotating shaft 34 and unnecessary wear upon the drive shaft pressure seal 33.
The housing 12 of the cable-injecting device is provided with cable entrance and outlet ports 36 and 37, respectively, through the outer wall 16 therefo. Preferably, bosses or nipples 38 and 39 are formed or welded or threaded to the outer surfaces of the outer Wall 16 to serve as guides for the cable 30 entering and leaving the housing 12. The axes of the ports 36 and 37 through the bosses 38 and 39 and the wall 16 are tangential to the grooves 28 in the grooved ring gear 26 and may be substantially parallel to each other. Besides cable ports 36 and 37, the housing 12 may also be provided with an injection port 42 for introducing lubricating material between bearing 17 and the ring gear 26. The boss 39 may be provided with a flange 43 or any other suitable coupling or connection, by which the housing 12 may be secured to the top of the lubricator 31. VThe other boss 38 may be threaded as at 44 for connection to any suitable pressure seal or closure device 45 adapted to be secured to the housing 12 or boss 38 and tit around the cable 3G, so as to close the annular space 15 in the housing 12 in a iluidtight manner. Preferably, the pressure seal 45 is of a type disclosed in a copending application, No. 182,970, liled September 2, 1950, now U. S. 2,670,225. The upper end of the seal 45 or the boss 38 is provided with a port 48 in communication through a conduit 46 with a reservoir (not shown) containing a relatively viscous transfer or sealing material such as heavy oil or grease. W axes, asphalt or emulsions thereof, glue sugar syrup, paraffin, water, drilling muds, or any viscous material may be used as pressure fluids.
The viscous transfer fluid is injected through port 48 into the bore of the boss 38 and sealing device 45. The transfer fluid is supplied from a reservoir at a pres sure slightly greater than the well pressure so that a high pressure well seal is formed between the cable 30 and the walls of the boss 38 and seal 45. Since the clearance btween the cable 30 and the walls of the boss avancee -38 and sealingdevice 45 `'may be in the Aorder of `is :formed `within the bore .ofthe apparatus. `The source of pressurefor injecting the transfer uid may comprise the utilization of :the well casing pressure through a conduit 47, or the employment of a compressor such ras .an ainoperated vhigh-pressure power gun.
A cable-injecting device of the above-described design allows :a relatively Vlarge diameter grooveddr'iving wheel to be mounted in` a pressure-tight 'housing lof hollow, `torus ring construction, said vhousing having walls of minimum weight and thickness for withstanding high well pressures.
Mounted `in the `annular space 15 ofthe pressure-tight housing l2 below the grooved :driving wheel 26 are guide `or transfer rollers 5.0. These rollers 50 lguide the cable 30 as it leaves fone `groove 2 8 of the driving wheel 26 Yand lead it into the `adjacent l groove. The rollers 50 are mounted `on :shafts 51 which :rotate in recessed bearings '52and 5.3 l'formed in wall 18 and cover plate 19 of the housing 12, ras shown in Figure `2 `of the drawing. The surface ,of the Vrollers50 is provided with one or more Agrooves 54, the number` of grooves on the roller 50 heing at least one less than the Vnumber of grooves 28 in the driving wheel 26. Each grooved roller 50 is mounted on its shaft 51 so :that it is positioned beneath the grooved portion of the `driving wheel 2,6. The axes of `the guide rollers 50 are slightly `askew to the Vaxis of the `driving wheel 26 so that the cable 30 contacts Ythese rollers 50 with rolling Contact.. The rollers tare small in diameter so as `to reduce the size of the `annular space 15 in the pressure housing 12 in which Ithey `are located. Preferably, a plurality of rollers `Si) are employed of varying diameters as shown in Figure l ofthe drawing, said rollers 50 being positioned adjacentxthe` periphery of the driving wheel 26 -so as to llimit the `curvature of the cable passing over the rollers to nearly `that `of `the relatively large diameter `driving `wheel 26, since `a very short bend in the cable woulda-shorten the life .of the cable considerably. This is effected `by arranging the axes of the several rollers along lthe line `of `an `arc having substantially the same radius `as the wheel or sheave 26. This arrangement-llas .the advantage Aof giving the present injector substantially ,the Lgripping power of a two-sheave device whilelimiti-ng the space .occupied thereby substantially `.to that .of a single Vsheav device. t
The several guide rollers 50 are positioned `so as yto allow the cable 30 to contact each groove of the driving wheel 28 over `approximately `an 180 tare. The axes of the rollers 50 `are parallel `to each other, but are skew to the axis of the driving wheel `by `an angle u (Figure 3) where .o4-are an D P being the `distance between the centers of :the :grooves 28 and D is the diameter tof the `driving wheel 26.
One or more idling pressure wheels ,57 and 58 (Figure l) may be provided Ato increase the pulling capacity ,of the driving wheel by pushing :the ,cable 30 deeper into the grooves 23 of the wheel `26. Anynnumber of -these Vidling wheels may be employed and they are preferably located in the housing 12 so that theyexert pressure `on the cable 30 just before .it leaves the driving wheel 26 prior to its entering the well, since the frictional force produced at this point is multiplied `by `.the other grooves `2S to give a greatly increased pulling capacity to `the driving wheel 26. .Idling wheels of the type shown at 57 are pivotally attached by means of a pin 59 to the wall 18 of the housing 12 .and are spring loaded'by means of a spring 60 to produce a continuous additional friction force between the `cable 39 `and the driving wheel 26. Alternately, anfidler wheel 58 ,is shown in 8 Figures l and 2 may be eccentrically mounted oda shaft 61 which extends through the wall 18 of the housing 12 in a iuidtight manner. The radial pressure ex- -erted by idler wheel 58 on the cable 30 may be adjusted to any desired value `from outside the housing 12 Yby merely turning the shaft 61 of the idler wheel 58 one direction or the other.
In operation, the above-described apparatus is affixed lin a ilu'idtight `manner `to the top of a lubricator 31 which is in turn secured to the top `of a wellhead (not shown). `Rather than have the boss 39 support the weight of the housing 12, the housing is normally secured to some fixed support (not shown) adjacent the wellhead by pass ving `bolts through the bolt holes 14 in plate 13 of the housing 12. With the housing 12 mounted on the 'lubnicator 31 and the well pressure shut off from the housing 12, the sealing element 45 may be secured to the inlet cable boss 38. The 4cover plate 19 (Figure 2) `of the housing i2 is removed so that an end of the cable 39 may be forced up sealing member 45 and yboss 38. `.Cable 30 is then wound over the grooved wheel 26, .between the wheel 26 and .the idling wheels 57 and 58, down below the `guide or transfer wheels 50 and up over the `wheel 26 again in another groove. One or more wraps of cable .30 may be taken around the driving wheel 26 and the guide rollers 50 depending upon the pulling capacity needed to force the cable 30 `into the high pressure well. As the last wrap of ,cable comes .oft of the grooved wheel 26, the end thereof is passed ,out the cable port 37 and -into the well lubricator 31 Where the tool or instrument Vto be inserted into the well isthen attached to the end of `the cable. The cover plate 1'? (Figure 2) is then screwed on the housing 12 to :close the housing in a fluidtight manner and transfer or Sealing duid is injected through port 45 (Figure l) `tto seal .off `the cable 30 in the sealing element 45.
The housing l2 may now be subjected to wellhead pressure by the opening of the necessary valves (not shown) at lthe wellhead. The tool and cable 30 attached thereto may be lowered into the well by rotating .the pinion gear 32 which in turn rotates the ring gear .and driving wheel 2.6, and thus pulling the cable into `.the `chamber l5 against the pressure therein, no force being thereafter required to force the cable into the well, which is of the same or lower pressure as the chamber 15. The multi-grooved injector wheel 26 is designed to allow several partial wraps of cable around the wheel so as to give high frictional pulling capacity to the apparatus while at the same time eliminating the disadvantages of a wheel having several wraps in a single wide groove. The cable can be passed over Vthe driving wheel `26 `as many `times as desired to increase the frictional pull between the cable and wheel 26 without having any sliding contact between the cable and wheel which would tend to wear the cable. A plurality of wedging grooves 28 as shown in Figure 5 of the drawing, having rounded bottoms can be used for `high pulling capacity with little harm to the cable 30.
It is to be noted that the cable 30 which rests in the grooves 28 of the large-diameter wheel 26, is in frictioual contact with the wheel through at least one-half the circumference thereof, the frictional forces set up between the wheel and the cable being sufficient to pull the cable 30 through the pressure seal 45 and force it out the cable port 37 and into the well. A test run on a driving wheel `26 having three grooves 28 therein showed that 4.6 times the instrument weight could be lifted with a single `-wrap of logging cable in one groove, ,15.3 times the instrument weight with two 180 wraps of cable, and 56 times ,the instrument weight with three 180 wraps of cable. Since each partial wrap (1.80") of the cable around the wheel 26 tends nearly to multiply the pulling capacity of the .previous groove, a multi-grooved wheel cable injector of the present design can be constructed to have `sufficient pulling capacity without the necessity of employing manually operated pressure wheels. However, if desired, additional .frictional forces may be applied to the cable 30 by employing one or more idling wheels 57 and 5.8 which are mounted in a fixed or adjustable manner in the housing 12. These idling wheels 57 and 58 exert a uniform and adjustable radial pressure on the cable 30 to increase the total frictional gripping force of the grooved' wheel 26.V
The path of the cable 30 over the driving wheel 26 and the guide rollers 50 is shown in the oblique projection in Figure 4 of the drawing. The cable 3i) enters one groove of the driving wheel 26 and turns with the driving wheel until it is lifted out of the first groove by the series of guide or transfer rollers 50. The rollers 50 guide the cable so that when it comes in contact with the driving wheel again for the second time around, it rests in the second groove, and thence continues over the wheel and the rollers again and up on the wheel and into the third groove thereof.
The cable injector in its pressure housing 12 is subjeeted to a fluid pressure of at least that of the wellhead pressure. lf the uid pressure within the housing 12 is allowed to drop below the Wellhead pressure, the differential pressure between the well and the housing 12 tends to lift the cable 30 out of the grooves 28 of the driving wheel 26 and thereby substantially decreases the pulling capacity of the driving wheel 26. This inherent feature of a wheel-type cable-injecting device can be employed to advantage if the fluid pressure within the housing 12 is maintained at a value greater than the well pressure. For example, if a logging cable 30 having a cross-sectional area of 0.10 square inch is injected into a 3,000 p. s. i. Well by means of a cable-injecting wheel having a pulling ratio of 40 to l, the injector must normally pull or inject the cable into the Well against the well extruding force of (3000)(0.l)=300 pounds. However, if the fluid pressure within the injector housing 12 is kept at 3200 p. s. i. the 200 p. s. i. pressure differential would tend to extrude or force the cable from the housing 12 into the well with a force of (200)(O.l0)=20 pounds. Since the pulling capacity of the driving wheel 26 is proportional to the cable tension on the well side of the wheel, the additional twenty Vpounds of cable tension would increase the pulling capacity of the driving wheel by (20 lbs.)(40)=800 pounds. At the same time, the 3200 p. s. i. fluid pressure which tends to extrude the cable through the cable sealing device with a force of (3200)(0,l0)=320 pounds is easily overcome by the additional 800 pound capacity of the driving wheel.
The present cable-injecting device, which has been described liereinabove with regard to injecting cables or wire lines into wells for purposes of logging, etc., could also be used for injecting exible tubing into a pressure well. While lunning the tubing into a well, either end of the tubing could be plugged or capped to prevent the well fluid from escaping therethrough. If the end of the tubing outside the Well is plugged so that the well fluid pressure acts internally on the walls of the tubing, the injector mechanism housing 12 must be maintained at a pressure at least equal to the pressure within the tubing. This is necessary due to the fact that if the pressure within the housing 12 is less than the pressure inside the tubing being injected into the well, the Bourdon said cable ports'being in fluid-tight communication with the well, sealing means connected to the other cable port for passing a cable therethrough, a wheel rotatably supported within said annular housing, said wheel having a plurality of circumferential grooves in the outer surface thereof, said grooved wheel being in frictional engagement with saidcable over a substantial portion of the circumference of said wheel, a plurality of guide rollers positioned adjacent to a portion of the periphery of said grooved wheel within said housing for transferring said cable from one groove in said wheel to an adjacent groove, and means extending through said housing for rotating said wheel. V
2. An apparatus for inserting a cable into a highpressure well comprising an annular housing having inlet and outlet cable ports through the walls thereof, one of said cable ports being in iluidtight communication with the well, sealing means connected tothe other cable port for passing a cable therethrough, a wheel rotatably supported within said annular housing,- said wheel having a plurality of circumferential grooves Vin the outer surfacerthereof, said grooved wheel being in frictional engagement with said cable over a substantial portion of the circumference of said wheel, a plurality of guide rollers positioned in an arc adjacent to a portion of the periphery of said grooved wheel within said housing for transferring said cable from one groove in said wheel to an adjacent groove, said arc having a radius substantially equal to that of said groovedwheel, the axes of said guide rollers being skew to the axis of said grooved wheel, and means extending through said housing for rotating said wheel.
V3. An apparatus for inserting a cable into a highpressure well comprising an annular housing having inlet and outlet cable ports through the walls thereof, one of said cable ports being in uidtight communication with the well, sealing means connected to the other cable port for passing a cable therethrough, a wheel rotatably supported within said annular housing, said wheel having a plurality of circumferential grooves in the outer surface thereof, said grooved wheel being in frictional engagevment with said cable over a substantial portion of the circumference of said wheel, a plurality of guide rollers positioned in an arc adjacent to a portion of the periphery of said grooved-wheel within said housing for transferring said cable from one groove in said wheel to an adjacent groove, said arc having a radius substantially equal to that of said grooved wheel, the axes of said guide rollers being skew to the axis of said grooved wheel, said guide rollers having at least one circumferential groove, in the outer surface thereof, the number of grooves in said guide rollers being no fewer than one less than the number of grooves in said wheel, and means extending through said housing for rotating said wheel.
4. An apparatus for inserting a cable into a highpressure well comprising an annular housing having inlet and outlet cable ports through the walls thereof, one of said cable ports being in fluid-tight communication with the well, sealing means connected to the other cable port for passing a cable therethrough, a wheel rotatably supported within said annular housing said wheel having a plurality of circumferential grooves in the outer surface thereof, said grooves being of a size to receive thecable therein, said inlet and outlet cable ports being positioned on opposite sides of said housing, the axes of said ports being substantially tangential to said grooved wheel whereby said grooved wheel is in frictional engagement with said cable over a substantial portion of the `circurnference of said wheel, a plurality of guide rollers positioned below and adjacent to a portion of the periphery of said grooved wheel within said housing for transferring said cable from one groove in said wheel to an adjacent groove, and means extending through said housing for rotating said wheel.
5. An apparatus for inserting a cable into a highpressure well comprising an annular housing having inlet and outlet cable ports through the walls thereof, one of said cable ports being in iluidtight communication with the well, sealing means connected to the other cable port for passing a cable therethrough, a wheel rotatably supported within said annular housing, said wheel having a plurality of circumferential grooves in the outer surface thereof, said grooved wheel being in frictional engagement with said cable, a plurality of guide rollers positioned adjacent said grooved wheel within said housing for transferring said cable from one groove in said wheel to an adjacent groove, the axes of said guide rollers being References Cited in the le of this patent UNITED STATES PATENTS 1,974,361 La Neve Sept. 18, 1934 2,567,009 Calhoun et al Sept. 4, 1951 2,630,180 Summers Mar. 3, 1953 2,677,427 McKinney et al. May 4, 1954