US1915219A - Apparatus for use in oil and like wells - Google Patents

Description

June 20, 1933. J. FERGUSON APPARATUS FOR USE IN-OIL AND LIKE WELLS Filed April 15, 1929 3 sheets-sheet 1 5 5 5 L u i W www,

June 20, 1933. J. FERGUSON 1,915,219

` APPARATUS FOR USE IN OIL AND LIKE WELLS Filed April 13, 1929 a sheets-neet 2 June 20, 1933. J. FERGUSON A APPARATUS FOR USE IN OIL AND LIKE WELLS Filed April l5, 1929 3 Sheets-Shea@ 5 MV1/YM' Patented June 2Q, 1933 Y, L9 l 5,2

A. unirse STATES PATENT vifi-icaN JGLLN FERGUSON, OF POLLOKSHIELDS, GLASGOYII, SCOTLAND .APPARATS FOR USE IN OIL AND LiKE WELLS Application filed April 13, 1929, Serial No. 354,901, and in Great Britain Api-i1 17, 1928.

This invention comprises an improved ap- Figure l illustrates an end elevation of the paratus for use in oil wells and the like. mechanism for feeding forward the cutter n oil wells it is customary to first sink a or saw. A cylindrical casing of large diameter, there- Figure 5 illustrates a section through the after sink a casing of slightly smaller diupper part of the apparatus to a larger scale anieter whiclicxtends from the groundlevel and also showing a portion of the line of to a greater depth than the first, and in like shafting and enclosing tubing.

' manner sink other casings, each succeeding Figure 6 shows in section to a larger scale one being of less diameter tlianthe former the tool holder and the means for feeding if? and extending from the ground level to a forward the cut-ter or saw the latter also @3' greater depth. i being shown. Y

It will thus be apparent that parts of the Figure 7 is an end elevation of Figure 6 well are formed of several concentric cas# looking from the left and Figure 8 is a secings and while it is desirable to so reinforce tional plan view on the line 8-8 of Figure f'f the well to a certain extent, it is customary 6, the Cutter Ol SlW bllg' OIDGdto remove what may be regarded as superflu- Figure 9 shows the preferred means by aus casing. which the speed of rotation ofthe cutter or lr That is the portion of certain of the inner saw about the longitudinal centre of the apcasings is cut away at a level just above the pernus Can be varied. 1 foot of the enclosing casings, the portion of Figure l0 is a sectional end elevation of the cut casings above said level being then Figure Qlooking to the left. 1 fem {,Ved Figure l1 illustrates a portion of the My invention has for its object to provide ratchet'wheel and clutch by which it can be improvements whereby the casings can be qulokly brought into and out of Operation. les mOi-e ,easily and expeditiously Cut than for- Figure l2isafragment of the ratchet wheel t nierly. showing la pair of co-operating pawls.

yMy invention has for its object to provide Referllng t0 the drawings I- y an improved tool for the purpose set forth l Clelgllltcs all Outer casing and 2 an inwlierein the various operations can all be HQI CilSlP-g 0f W1l, 3 1S the rotary cutter or egecd automatically on power being transsaw, 4 is the inner line of shafting and .5 is 1u', reed to the 13001 Within the WelL Y v an outer line of tubing enclosing the shaft- My invention has further for its object to '111g 4 provide an improved means for supporting rl`lie line of shafting l is formed of an interand transmitting power to the tool, connected series of relatively short lengths, w t," In order that my invention will be proper- 91Ch111g13l1, &t ODG end thereof, being squared d ly understood I have hereunto appended eX- 18 at 41, Whleth@ Other Glfll 0f @heb length planatory sheets of drawings whereon; is enlarged and correspondingly recessed as Figure l illustrates diagrammatically a at ith O I'QCGW the {Slued @11d 0f an intel'- preferred construction of apparatusy in aefttlng length, see Figure 5. The top length coi-dance with my invention, part of the Sad 11116.@ Sllatmg ljeCClVGS the Squillefl lgngth of the driving Shaft and part the (5nd Of {L Spllldle 6 lLO WlllCh lS keyed t beVl line of enclosing tubing being shown broken Wheel 7 1n mesh Wth a beVel Wheel 8 keyed LWML to a short spindle 9. The latter is jour- Figure 21s a. somewhat similar view to that nailed in bearings 10 carried by a pedestal 11. shown in Figure l,but showing certain parts 011 end 0i' @he Splnfu 1S CODDGCteCl by in Section and to a larger Seal@ means o fa universal Joint to one end of a Figure 3 is an end elevation 0f the upper telescopic connecting rod 12 which latter is part. of the apparatus showing the pawl and connected in like manner to the shaft 13 ratchet mechanism for impartinga slow rowhich carries the fast and loose pulleys 14 and l GG tary movement to the line of tubing. lli-a. The other end of the spindle 9 trans- I thereon by means of a pinch screw 16a a worm vwheel 15 which is mounted to rotate on they base 16 supporting the pedestal 11, ball bearings or other anti-friction bearings being introducedl between the said wheel and base.

The upper end of each length of tubing carries a ball race 5d or washer on which rests the shoulder formed by the squared-end 4b of the length of shafting enclosed thereby. Thus each length of shafting is freely -supported by its length of enclosing tubing.

Near the lower end of the line of shafting and line of enclosing ltubing is a guide 17 formed of a frame carried by collars 18 free on the line of enclosing tubing and provided with a series of spring arms 19 having contact pieces 19 which bear on and grip the casing to be cut. Immediately below this guide and secured to and forming part of the line of tubing is a cylindrical casing 2O tothe lower end of which is screwed or otheri wise secured a vertically slotted cylinder 21.

This cylinder, in addition lto being slotted vertically, is provided with three transverse slots 22, 23 and 24. A sliding member 25 which constitutes a tool holder, carries the rotary cutter orf saw 3, and is accommodated in the centre slot 23, the cutter or saw being operativelyl connected by means of a universal joint to the one end of a telescopic connectingrod 26 the other end of which is connectedin like manner to the lower end of the line of shafting 4:. Located in the cylinder 2O and connecting' the two lowest lengths of the shafting is reducing gear carried in the gear box 27. y

It willtherefore be apparent that onv the fixed pulley being driven the line of shafting 4 is driven through the connect-ing rod 12, spindle 9 and bevel gearing 8 and 7, and said shafting transmits its motion through said speed reducing gear located in the gear box 27 and connecting rod 26 to rotate the cutter or saw 3 about its own axis.

The saidspindle 9 transmits-through an eccentric device and connecting rodA 28 a reciproeating movement to a cross head 29 which travels on the guide rods 30 and which carries the two rods 31. These rods, at their lower ends, are provided with pawls which f engageV with a ratchet wheel 32 mounted on the shaft 33 of a worm 333L which meshes with the worm wheel 15. Said worm shaft 33 is journalledin a casing 331 cast integral with thebase 16of the pedestal. f

It will therefore be seen that simultaneously with` the rotation ofthe line of shafting 4 the line of tubing 5 is slowly rotated from the spindle V9 by means of the said pawl and ratchet mechanism and worm and worm wheel, the line of tubing being connected to Y vcutter or saw 3, while being rotated about its own axis by means of the line of shafting 4, is also rotated, but much more slowly, about the longitudinal centre of the apparatus.

The means for effecting the radial feed of the tool will vnow be described. i

Guides 22at and 24a, each having a rectangularopening therein, are fitted into the slots 22 and 24; formed in the cylinder 21 and are fixed in position by the transverse bolts 22b and 24h, see particularly Figures 6, 7 and 8.

Avvertical bar 35, rectangular in cross section and provided with a slot 35ain the form of a quadrant, is fitted within the holes in said guides 22a and 24 and also passes through a vertical slot formed in the sliding member or tool holder 25.

A screw threaded spindle 36 is threaded through a corresponding internally threaded nut 37 secured .to vthe lower end ofsaid bar 35.

Said spindle does not rotate but is secured to a guide formed by a. frame 38 having spring arms 39 provided with contact pieces v39a which grip the side of the casing being eut.

Therefore, while the cutter or saw 3 is being simultaneously rotated about its own axis and about that of the centre of the apparatus, the internally threaded nut 37 is being slowly rotated on the screwed spindle 3G which latter is held, stationary. Consequently said nut travels vertically on the screw threaded spindleV andimparts a like movement to the vertical bar 35.l A cross ypin 23b carried by the tool holder engagesv with the quadrant shape slot 35a and the latter, acting like an inclined plane, imparts a radialfeed movement to theftool holder, and therefore to the cutter or saw carried thereby. The shape of said slot, is such that after the cutting operation is eected the cutter is automatically within which is fitted a screw spindle 9c and an internally screw threaded sleeve 9d screwed thereon'. Said sleeve carries an outwardly lik? projecting stud9e to which is connected the upper end ofthe connecting rod 28.

Said screw threaded spindle is prevented from moving longitudinally by means of a pin 9t passing through a hole in they disc and a groove in the head ofthe spindle, but it can be rotated and for that purpose may be provided with a tommy hole.

By rotating the said spindle the position ofthe sleeve 9d can be adjusted thereon and therefore the eccentricity of the centre of the stud 9e with respect to the centre line of the spindle 9 can be regulated. As the degree of eccentricity controls the amount of travel of 1 the reciprocating cross head 29 and the travel of the pawls, the speed of rotation of ratchet' wheel and wo-rm wheel, the line of tubing and the tool holder can be regulated so that the circumferential travel of the cutter or saw about the longitudinal centre line of the appa` ratus can be regulated to suit any diameter of casing being cut.

In order to impart a very steady rotary movement to the tool holder' l provide two pairs of pawls, one pair pullinground the ratchet Wheel when the cross head moves upwards and the yother pair pushing round the ratchet wheel when the cross head moves downwards so that a small movement is imparted to the ratchet wheel on both the up tial and radial feed motion beingy imparted to the cutter or saw.

vWhere a rotary movement is imparted to a ratchet wheel by means of a cooperating'reciprocating pawl such movement must be a step by step movement.

By the provision of the pawls pulling alternately upwardly and downwardly at the opposite sides of the wheel, a substantial continuous movement is imparted to the ratchet wheel and thereafter to the wheel.

A pair of pawls 4l and 4la are shown in Figure l2 and from which it will be seen that while one of the pawls is in engagement with a tooth of the ratchet wheel the yother is not. By such provision the amount of lost idle movement is reduced by half and this permits of fine adjustment of the speed of rotation of the ratchet wheel.

Said pawls are carried between two plates 42 provided with inwardly projecting curved ribs 43 which fit within corresponding annular grooves in the ratchet wheel, the cooperating ribs and grooves serving-as a guide for the pawls.

The ratchet wheel is secured on the tapered end of the shaft 33'by means of a wing nut 44. By slackening said nut the ratchet wheel can be allowed to rotate independently of the said shaft so that no rotary movement is imparted to the latterland consequently no movement imparted to the line of tubing v and tool holder, the plates carrying the cutter or saw then rotating only about its own axis. f

In cutting casings it is necessary that the cutter or saw should be so positioned 'that it Will commence to cut almost immediately after the feed forward movement commences and consequently 'provision' must be made for this in cutting casings of various diameters.A l

ln Figure 6 the tool holder is shown provided with three transverse holes through either of whichthe pin 23b can be passed and by this the position of the tool adjusted within the limits governed .by the distance said holes are apart.

.The cutter, or saw is not directly mounted on thetool holder but is carried by aI bracket y orblock 45 which fits within a slot formed in the end of the tool holder and is held therein yby means of a clamping plate 45a and bolt. and nut 46 and 46a.

By adjusting the tool holder and. bythe provision of thin packing strips47 inserted between the rear end vof the yblock and end of theslot in the tool holder adjustment can be made to suit any diameter of casing to 1 be cut. f

lt will be understood that adjustment can also be effected by the use of sliding tool holders of various sizes and in combination with such packing strips. i

In use a spindle 36 with correspondingnut is selected to give the desired rate of radial feed to the cutter or saw and is fitted to the foot of the slotted cylinder 21.

The cutter or saw is adjusted by means of the tool holder and packing strips so that it will commence to cut almost immediately after the radial feed motion commences.

- The shafting 4` and enclosing tubing 5 are adjusted to the required length and supported centrally within the well by the base I6 l of the pedestal and by the two guides carried by the said tubing near the lower end thereof and bearing on the inner wall of the casing to be cut, i. e., the casing 2.

On the fixed pulley being rotated the cutter or saw is rotated about its own axis by means of the line of shafting 4 and is simultaneously rotated bodily in a circularpath about the longitudinal centre of the appara- 1 33 tus, orv casing being cut, but at a relatively very slow speed, by means of the line of tubing.

Also simultaneously with the said two movements the cutter or saw is fed slowly` outwards by means of the screw and nut feed device and the inclined plane action ofthe slot 35a. The cutter or saw therefore travels round and cuts into the casing 2 while rotating about its own axis, suchl operations being continued until the said easing is completely cut through.

The superfluous casing can then be removed and the apparatus used to effect further like operations. l s

Should it be desired to quickly or tempes rarily stop the circumferential rotation of the cutter or saw about the longitudinal centre of the apparatus, this can be quickly done by merelyslackening the wing nut 44 as explained above, and should it be desired to alter the rate of such circumferential movement, this can be done by rotating the screwed spindle 9*. i

The slots a in the bar 35 may be designed, as shown, so that it imparts a quick initial movement to the tool holder, thereafter a much slower movement,and, when .-the cut- Vting operation is completed automatically effects a quickreturn movement without stopv ping or altering the direction of the drive.

A f The line of tubing formed of rigidly inter,-

connected lengths of tubes forms a rigid support forthe tool while the short lengths of independently supported shafting enables the tool when located at considerable depthsv to be operated from the surface. Each length of tubing and shaftingis conveniently about 22 feet. f

l. An apparatus for the purpose set forth comprising a rotary cutter or saw, a holder for said cutter or saw, an inner line of shafting to rotate said cutter or' saw aboutits L own axis, a rotatably mounted line of tubing enclosing said shafting and by which the holdertogether with the'A cutter or saw is supported and rotated, a guide member to grip the inner wall of the tube being cut and l means to feed the saw or cutter outwards comprising a non-rotatable screw carried. by said guide member, a nut to travel on said screw, a vertically sliding member having a longitudinal slotand operatively connected to the nut and a transverse pin vcarried by the holderand engaging said slot, the said sliding member effecting the forward feed of the saw or cutter.

`2. An apparatus of the stated character comprising a rotary cutter, a holder for sai-d cutter, 'an inner shaft arranged 'to rotate the cutter about its own axis, a rotatably mounted tube enclosing said shafti-ng and by which the holder carrying the cutter is supported, means for rotating saidftubular casing with said holder, a guide suspended by the tubular casing and arranged to engage the tube to be cut, and means forfeeding the cutter radially outwards and comprising a nut and screw, one of which is rotated bythe holder and the other thereof held by saidV guide.

3. An apparatus for the purpose set forth comprising a rotary cutter or saw, a holder for saidcutter or saw, an inner line of shaftingto rotate said cutter or saw about its own axis, a rotatably mounted line of tubing enclosing 'said shafting and by which the holder of the cutter or saw is supported and rotated, a guide member to grip the inner wall of the tube being cut, and means to'feed the cutter or sawoutwards comprising a non-rotatable screw carried byA said guide member, a nut to travel on said screw, a vertically sliding member having a curved slot and operatively connected to the nut, and a pin carried by the toolholder and engaging the slot, the said nut and screw in combination with the pin and curved slot effecting a quick initial feed movement, thereafter a slow feed movement and a quick nal return movement.

' 4. An apparatus of the stated character comprising a rotary disc cutter orsaw, a support, a holder slidably mounted on said support and carrying said cutter or saw, a line of shafting to rotate the cutter or saw about its own axis, a line of tubing to rotate said support together withr the holder and the cutter lor saw, a driving member, gearing by which both the'line of shafting and the line of tubing are simultaneouslyrotated by said driving member, a stationary member suspended by the line of tubing but not rotating therewith, anda member mounted to rotate with the holder and cooperating with the stationary member by which the cutter or saw .is fed outwards. v

5. An apparatus for the purpose set forth comprising a rotary cutter, a holder therefor, a support for said'holder, an inner line of shafting to rotate said cutter about its own axis, a rotatably mounted iine of tubing enclosing said shafting and by which the support and holder .carrying the cut-ter is supported, a driving member to rotate said line of shafting, means to rotate the line of tubing also driven by said member and comprising a ratchet ;wheel operatively connected to the line of tubing, a rod reciprocated by the driving member, a housing carried by said rod and engaging' with the ratchet wheel so as to travel circumferentially thereon, at least one pawl Vcarried by saidhousing and arranged to engage with the teeth of the ratchet wheel when moved fl in one direction -and to over-ride the teeth when moved in- -the other direction and means for varying the stroke of said rod to 'vary the rate of travel of the support with cutter also driven by said member and comprising a ratchet Wheel operatively connect-ed to the line of tubing, an eccentric driven by the driving member, a reciprocating member connected tor said eccentric, means to Vary the degree of eccentricity of the eccentric and therefore the stroke of the reciprocating member, a housing carried by said member and engagingwith the ratchet Wheel so as to travel circumferentially thereon, and at least one paWl carried by the housing and arranged to engage With the teeth of the ratchet Wheel When travelling in one direction and to over-ride the teeth When travelling in the other direction.

JOHN FERGUSON.

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