US 3105546 A
Abstract available in
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Description (OCR text may contain errors)
W. G. OWNBY ETAL WELL PERFORATING CONTROL 4 Sheets-Sheet 5 Filed Sept. 14, 1959 INVENTOR:
A rra/INE y Oct. 1963 w. G. owNBY ETAL 3,105,545
WELL PERFORATING CONTROL Filed Sept 14, 1959 4 Sheets-Sheet 4 iNVENToRS w 6. om@
United States Patent O 3,15,546 VIELE.. PERFGRATENG CNTRQL W'arren Gillette Gwnby and Kenneth Robison, Hennen, Tex., assignors to Camco, incorporated, Houston, Tex., a corporation of Texas Filed Sept. 14, 1959, Ser. No. 839,381 Ciaims. (Si. 16o-55.1)
This invention relates to the preparation for operation of fluid producing wells and more particularly to an irnproved arrangement for directionally perforating from the inside of a tubing string and into a production formation and with direction control for effectively eliminating the likelihood of performing perforating operations in paths to intersect and damage other tubing strings of a multiple completion well.
An object of the invention is to enable two or more production strings to be lowered into final position within a well bore which traverses several production Zones and after they have been properly set, cemented and washed, to then perform separate perforating operations from the inside of each tubing string into selected zones respectively for completing the well.
Another object of the invention is to provide for the simplified use of wire line equipment to suspend and lower a perforating gun into proximity to a known depth to be perforated and then to be positioned and oriented through a combined longitudinal and rotational manipulation for controlling the range of a perforating operation within a region away from interference with other tubing strings extended therebelow.
A further object of the invention is to provide a perforating gun having its charges directed for projection within a limited circular segment of its body and a firing system which includes a magneto device whose pole pieces are exposed at the periphery of the body and in lixed relation to the projection direction of the perforating charges and are arranged in coded relation to magnet pole pieces carried within a tubing string region isolated at one side of the tubing string whereby gun travel through the tubing string and alignment of the two sets of coded pole pieces for extending lines of force from the magnet to the magneto device, assures performance of the perforating operation in the desired direction.
Other objects and advantages of the invention should become apparent in the following specification and accompanying drawings wherein FIG. 1 is a vertical section of a portion of a dual completion well illustrating the use of the invention; FIGS. 2A, 2B, 2C and 2D are companion views of the improved perforating device in part side elevation and part longitudinal section and with FIGS. 2C and 2D also showing a fragment of a tubing string nipple in longitudinal section; FIG. 3 is a perspective view partly in section of a portion of a tubing string nipple having a longitudinal row of permanent magnets in a given side region of the circular tubing nipple; FIG. 4 is a diagrammatic vertical sectional view of a Well installation involving multiple production tubes with double packers in a cased hole and an alternative arrangement of magnets for controlling the direction of perforation; PEG. 5 is an enlarged view partly in elevation and partly in longitudinal section of a tubing string coupling element on which magnets are located exteriorly thereof; FIG. 6 is a perspective view of a fragment of one of the magnet mounting rings and FIG. 7 is a wiring diagram.
Following the drilling of a well whose bore has penetrated several fiuid containing formations as indicated at A, B, C and DV in the diagrammatic FIG. l illustration, it may be feasible to install separate tubing strings in parallel for completing the well to different formations and also provide for later blocking olf a previously completed zone and bringing in another zone through any of the production strings. Accordingly, at least one of the tubing strings should be of a length to traverse all formations and other strings economically can be shorter to reach upper zones, as seen in lFIG. l, and which for convenience shows a pair of tubing strings positioned in an uncased bore wall and set permanently in cement lilling the bore hole around the tubes.
To reduce the work and load on installation equipment involved in simultaneously making up two long tubing strings and lowering them as a bundle into a well bore, it is here proposed to make up and lower a single tubing string 1 of a length to pass all of the formations and eX- tend to the deepest thereof. Such string will incorporate in predetermined spaced relation various types of nipples and inserts for co-operation selectively with control accessories of various types. One such insert is a special nipple Z having a laterally projecting hollow-fitting or odset receiver 3 which carries a dependent tubing section 4 of relatively short length to extend below the receiver 3. A lateral port or side passage 5 in the nipple 2 joins the interiors of the tubing string l and the receiver 3 for their selective communication or block-olf, depending on flow paths to be established, under control of a suitable tool, as, for example, a hollow ow control device 6 of a wire line retrievable type, removably mounted Within the nipple 2 and in sealed relation therewith above and below the passage 5.
Above the communication port 5, the upper open end of the offset receiver 3 has a coupling connection at 7 Wit tie lower end of a second tubing string y8 in mignment `with the depending tubing section 4. Additional nipples 2 at other levels in the tubing string l and with oset receivers variously circularly spaced, will enable other production strings to be set in the well bore.
As part of the nipple 2, there twill be placed in given positions a number of permanent magnets and similar magnet units can be incorporated in other tool receiving nipples in both strings at selected depth locations. The magnet unit 9 in the nipple 2 just above the side opening 5 is shown as having two vertically spaced rows of circularly spaced apart magnets and are for co-operation with a known ty `e of running tool suoh as that disclosed in patent application S.N. 803,049, tiled March 30, 1959, which detachably mounts .a control device and is lowered by wire line equipment so that magneto devices embedded in the running tool will be inuenced by the magnets upon alignment therewith for releasing and setting Within the tubing string any of various types of conventional subsurface well tools such as the ilow control device 6 previously described. When a given tubing string has a series of magnet units 9 in spaced apart relation, the vertical spacing of the rows of magnets in each ring usually is different than others so that running tools ha-ving pole pieces coded to certain magnet units can be employed for setting tools at selected levels.
rl`he nipple 2 is also shown in FIG. l as having immediately below the side passage S a pair of magnet units it?, one in each tubing string. ln this instance, in addition to vertically spaced apart rows of circularly spaced apart magnets, each unit 1t? has Iat one side thereof a single Vertical row of magnets and the several magnet rows are for coded co-operation with field poles associated with magneto devices yforming a part of a perforating gun assembly whereby a per-forating operation will occur only when the perforating charges `are at a given depth and are directed in ia predetermined radial direction as will be controlled by alignment of the field poles of the several magneto devices and the pole pieces of the magnets in the several circular and vertical rows, as will later be referred to in greater detail. For permitting selective perforation at any of several productive formaaioaefie tions traversed by a well bore, several magnet units ill diiiering from one another as to spaced locations of the rows of magnets `will be incorporated in a tubing string at given depths related respectively to the formations.
After the multiple tubing string assemblies have been lowered to the desired positions in the well bore, they can be cemented in place by known procedures by which a cement slurry is directed, for example, through the tubing string l, into the open hole so as to till the bore hole surrounding both tubing strings and provide a solid plng l2. The bottom of the extension tubing 4 Imay be closed by a suitable plug against entry of cement slurry and after the cement has set a perforating gun will be lowered through the string l for forming the flow openings ll into the lowermost formation A. Such perforating gun can be hung in spaced relation corresponding to the yknown distance between the formation A and the magnet assembly lil next thereabove and from a wire line running tool having magneto devices to be inlluenced as hereinafter described by the magnet assembly ld within the tubing string l. Perforations into an upper formation B are also performed by a wire -line suspended device and controlled directionally so as to pierce and coinplete dow passages into the formation on radial lines angularly spaced away from intersecting relation withV the downwardly projected tubing l. Well working devices can then be used for producing both Zones and for performing various workover operations. Reworking can include closing oli previously completed zones Iand new perforating jobs at other zones at which gun controlling sets of magnets in tubing nipples were provided.
In FIG. 2C there is indicated the detail of la magnet assembly lll. A tubing string nipple portion 13 is shown with an internal counterbore or pocket which receives in succession a magnetic spacer tube i4, a nonmagnetic ring l5, a magnetic spacer ring 16, a nonmagnetic ring i7 and a series of magnetic spacer rings i8. Examples of magnetic materims include iron and soft steel and of nonmagnetic materials include copper, aluminum and resin Iplastics. rIhe longitudinal lengths of the several rings 1548 can be of predetermined dimensions and the rings can also be interchangeably related so that the upper nonmagnetic ring 17 can be variously spaced axially in equal steps from the lower nonmagnetic ring l5. Adjustment in such spaced relation will enable a selective coding of theparts to similarly equally spaced elements of control parts which `are to respond to the magnetic fields of permanent magnets 19 and 2li fixedly inserted in the nonmagnetic rings 17 and 1S and comprised of short plugs or discs that `extend radially through the respective carrier rings and are circularly spaced apart in annular rows. The inner and outer faces of the magnets 19 and 29 are of opposite polarity and in each instance the lines of force between opposite pole faces extend through the nonrnagnetic carrier ring and protrude inwardly of the innermost pole and into the hollow tubing string space.
Isolated to one side of the tube i4 and ritted Within a longitudinally elongated opening, there is a nonmagnetic strip 21 having projected therethrough a number of permanent magnets 22 vertically spaced .apart in a single longitudinal row and the lines of force between the inner and outer end faces of these magnets will loop into the interior space of the tubing string and pass through the nonmagnetic carrier strip 2l. When the fields of all three groups of magnets t9, 2li and 22 are simultaneously extended to inliuence magneto devices, there can be signaled the performance of work such as the well wall perforating operation. Each such magneto device can control the closing of switch contacts serially connected in an electric control circuit for supplying current in a tiring circuit to lire the explosive charges of a penforating gun. The gun with a set of magnetic devices attached thereto, consists of a wire line tool to be passaged through l the tubing string and red upon simultaneous closing of the serially connected switch contacts.
The three switches indicated at 23, 24 and 25 each constitutes the `magneto device referred to and operates under the diArsonval principle. Each has `a current receiving coil pivoted to respond to a magnetic held across ield pole pieces on opposite sides of the coil for closing a pair of contacts. Such pole pieces for the switch 25 are indicated lat 21e and 27 and are for lateral alignment with any of the series of plugs 28 arranged in proper vertically spaced relation in the wall 29 of the -body or a wire `line running tool assembly. This upper switch assembly can be variously adjusted longitudinally of the body for alignment of its field poles 26 and 27 -with any selected pair of plugs 28 for selectively modifying the spaced code relation between the two switches Z5 and 212-. The pole pieces of the lower switch 24 are iixedly mounted in alignment with magnetic plugs 3l) carried by the wall 29. Such lined mounting results from lateral seating shoulders suitably formed on the switch Z4 and the wall 29, together with the use of locating spacer sleeves 29a lining the interior of the body wall Z9 above and below the switch unit 2.3, as seen in FG. 2C.
ln the larrangement shown, the spacing of the severalV pole pieces for the two switches 25 and 24 is in coded relation to magnets i9 and Ztl whereby both switches would be closed. However, the lower switch 23 is not closed `since the ends or" its pole pieces7 comprising two circularly spaced rows of Vertical plugs 3l, are oircularly displaced from radial alignment with the eective fields of the single vertical row of magnets Z2. in other words, a rotational adjustment of the running tool from the relative position illustrated in FlG. 2C, ettected by rotational manipulation of its suspension wire line -will be needed to bring the field pieces 31 into iield relation or radial alignment with the magnets 22. for influencing the magneto switch 23 and completing a control circuit through all switches concurrently to actuate a suitable relay and close a tiring circuit for the perforating gun.
The perforating gun 32 of a generally conventional type, as seen in FiG. 2D, `has one or more vertical rows of radially directed perforating charges or shot 33 in a predetermined circular region and its upper end is illustrated as being i redly secured to the lower end of the running tool body 2% yand to constitute a lsolid unit therewith. Its explosive charges are connected to be tired by current supplied through a conduit t in a relay circuit controlled :by the series connected switches 23, 2f; and Y ZS which need to 'be closed concurrently to complete the circuit containing the relay. Because of the nonrotatable and spacer mounting connection between the perforating gun 32 and the running tool body 2%, there will be a fired angular and longitudinal relation between the locations of the pertorating shots 33 and the pole pieces 3l and direction of force projection through the tubing is positively controlled by the location of the set of magnets 2?. oriented at one side of the tubing.
For coding to any desired one of a series of tubing insert members or nipples having differently spaced magnets and by changing the vertical spaced relation between the switch units 24 and ZS, the upper unit 25 is fastened to the lower end of a vertically shiftable lpost 35 which extends upwardly the tool body 29 and, as seen in FIG. 2B, ihas a key 3o projecting outwardly therefrom through an elongated slot 37 in the body 29. On its outer face, the key 35 carries helical thread formations fitted to intern-al screw threads on a rotary sleeve 3S carried in a reduced diameter portion or annular notch in the exterior wall of the body 29 and normally protectively enclosed within an axially shiftable outside sleeve 3?. Near its upper end, the outer sleeve 39 is internally threaded to engage co-operating threads at itl on the body wall 29. To eiect a desired setting before a tool is run into a well, torque is applied manually to the sleeve 39 Ifor rotating the same and unthreading it from the screw threads it? to thereby separate and allow the sleeve 39 to slide down and expose the manually rotatable sleeve Rotation of the sleeve 3% by reason of its threaded engagement with the key 36 is converted into longitudinal movement of the switch adjusting post 3S for a selective position setting of the switch unit 25 in code relation to the switch unit 25:. After such setting, the sleeve 39 is raised and recoupled on the threads 46' in protective overlying relation to the rotatably adjustable sleeve nut 38.
ln the upper hollow part of the body 29, there will be located the electrical components, including such items as the batteries Bl and B2, the relay R and a master switch l1 whose circuitry is diagramed in FIG. 7. These electric batteries are sources for supplying current to the coils of the magneto devices 23, 24 and Z5, to a relay actuating circuit controlled by the magneto switches and to the relay controlled detonating circuit. A manually controlled master safety switch is located within the top of the tool body and includes a two position microswitch 41 which can be shifted between its positions upon relative movement of its upwardly extending post 42. lIn one position the gun detonators are grounded and all battery circuits are opened and the other position, established when the tool is about to be lowered, closes the battery circuits.
Post movement an upward direction is under influence of a coil spring d3 when a lateral screw stud 44 is backed out of engagement with a conical head end on the post d2. By reason of the co-operating tapered ends of the stud d-tand post 4Z, an inward threading of the post le will de, ress the post 42 against the resistance of the spring 43.
As previously indicated, when all three of the magneto devices or magnetically set switches 23, 2d and 25 are simultaneously influenced by magnetic fields, then electric current is transmitted to the erforating device, as will readily be apparent from the circuit diagram of PEG. 7. Here the manual switch 41 is represented as a grounded blade movable between two contacts, one of which is normally closed and grounds both sides of the squib or detonator 33 for safety purposes. This grounded switch blade also has connection through each coil of the magnetically set switches 23, 2d and 25 with a positive tap on the battery and connection by way of serially joined switch contacts of the switch units 23, Zd and 25 and through the coil of the relay Rl with the positive terminal of the battery B2. Both batteries have their negative terminals joined to the other or normally open contact of the manual switch 4l. To condition the control system for operation, the switch 4l is shifted to open its normally closed contact and to close its normally open contact. Thereupon, current from the battery Bl flows through the parallel coils of the magnetically set switches 23, 2d and 25 and biases the pivotally mounted coils against swinging movement from positions holding open their respective contacts. The tool unit suspended by a wire line can now be lowered into a well tubing string incorporating sets of differently spaced apart magnets. As these magnets are traversed during tool descent, their elds individually will be impressed on each movable switch coil and the coil under inlluence of the field will swing to close its contacts. Closure of any one of three series connected switches while any other of the two switches is open is ineffective for current llow in the circuit containing the coil of the relay Rl. By reason of selective position adjustment of the switch 25 through its shiftable post 35 and the rotary sleeve nut 3S, the spaced apart relation of the pole pieces of the switches 23, 2d and y25 will have been preset to match the space apart helds provided by a particular set of the several sets of magnets 22, 29 and 19 in the tubing string, whereby all three of the series connected coils of switches 23, 2id and 2S will be simultaneously influenced by magnetic fields only when the tool descends to the preselected set of magnets. Concurrent closing of the series connected switches enables battery EZ to energize the relay R1 for directing current from the battery B1 to the detonator 33 for firing the same.
To summarize the performance of a perforating operation and considering zone B of FlG; l is to be opened for production through the tubing string 3, the selector sleeve 38 on the running tool will be adjusted as required to preset the position of the relatively adjustable switch unit 25 in order to present its pole pieces in given axially spaced apart relation to the pole pieces of the xedly positioned switch unit 24 and which given spaced relation matches the known axial spacing between the fields of the pair of circularly arrayed magnets i9 and Ztl in the nipple l@ next adjacent and above zone fB. The gun perforator 32 will be ixedly attached to hang on the tool body so as to place the perforating charges 33 below the switch unit pole piece plugs 3l, Si? and 2S a distance corresponding with the known vertical spacing between zone B and the ields of the magnets 22, Ztl and 19 and also to tix the laterally directed perforating charges 33 in predetermined angnilar relation with the switch pole pieces 3l which, as previously indicated, are purposely oriented at one side of the tool wall. As was heretofore pointed out, such angular relationship insures aiming of the perforating charges at the time of subsequent tiring in the desired direction out of intersecting relation with the tubing string l. Finally, the safety switch 4l is shifted from its grounding position illustrated in FIG. 7 to its other position in which the circuits are conditioned for closing the firing circuit and the tool and gun assembly is lowered within the tubing string 8. When suspension line pay-out and tool descent brings the gun perforator within zone B, as seen in FlG. l, the pole pieces 2S, 3@ and 3l will be disposed for co-operation with the fields of magnets 19, 2d and 22. lf these pole pieces come within the iields in concert, the responsive actions of the eld coils for the series connected switches 23, Z4 and 25 effect switch actuation to energize the relay Rl for closing the gun r'iring circuit. Firing will not occur should the pole pieces 3l be angularly displaced from and outside the elds of magnets Z2. :Control of the direction of firing is by relative disposition of the oriented magnets and pole pieces and since the tool is suspended by wire line, it is not stabilized against turning about its longitudinal axis and it is free to swing and present its pole pieces 3l within the iields of the lixedly mounted magnets 22 to effect the firing when the charges are aimed away from the tubing string 1. Swing can be imparted to the tool through the wire ine by its manipulation at the wellhead and rotation of the line can be accompanied by some reciprocation for placing all the pole pieces within magnetic fields in unison.
Preferably, the relatively delicate control switches and other electrical components contained within the running tool are protected from mechanical shock by filling the housing with a suitable liquid and by balancing internal and external pressures in the manner illustrated in 2B, where the annular space between the post 35 and the housing 2? forms a part of the liquid enclosing chamber and which is closed by a piston or slide ring d5 operating within this annular space and exposed on one side to the illing liquid and on the other side to outside pressure at the wall opening 4t?.
An arrangement especially adapted for directionally perforating a formation from within a cased hole and between packers in a multiple completion installation is illustrated in FIG. 4. The well hole 55B, to be considered as lined by a casing Si, traverses several potential producing horizons, such as shown at X, Y and Z. A bottorn packer 52 is illustrated as being set between the formations Y and Z and around a relatively long production tubing string 53, the side wall of the hole having been perforated at 53 into the producing formation Z served by the string 53. A second tubing string 5d extends through the well hole in side by side parallelism with the production string 53 and terminates at its lower end at some predetermined distance above the bottom packer 52.
An upper packer 55 surrounds both strings 53 and 54 to seal oft` the well hole at a distance above at least one of the upper uid containing formations X and Y. The drawing illustrates formations X and Y in the space between the packers and perforations can be performed into either of these horizons for producing the well through the tubing string 54.
One, but preferably both, of the tubing strings will be made lup with nipples containing magnets for selective actuation of tool setting equipment having magneto devices as previously described, the magnets and setting tools being properly coded one to another. A pair of such magnet carrying nipples are diagrammatically shown at 56 in both tubing strings.
More particularly, the longer tubing string 53 in its downwardly projected portion between the packers 52 and 55 and in predetermined relation with each fluid containing formation, such as X and Y, is provided on the eX- terior thereof with groups of magnets arranged in coded sets for controlling actuation of a perforating tool diagrammatically indicated at 57 and constructed essentially as heretofore described and shown in FIGS. ZA-ZD. vIn other words, the tool will include a perforating gun having one or more ignitible charges directed to project outwardly on radial paths and also having a detonation cir- Vcuit under control of magneto switch means with outwardly facing pole pieces at least certain of which are segregated and isolated at one side of the tool in angularly spaced relation with the radial paths of projection of the perforating charges. In this instance, the tool 57 is to be suspended on the lower end of a'wire line 53 for lowering and turning manipulation through the tube 54 to below the lower end thereof and into lateral alignment with the formation selected for perforating.
Because of the relative angular relationship of the charge and the pole pieces in the tool 57, the gun, after having been lowered to a point adjacent the selected formation, will need to be manipulated through the suspension wire line 58 so as to eectively line up, both vertically and laterally, the coded pole piece terminals of the tool with the eld of actuating magnets and when this is done, the charge will be iired audits path of projection controlled so as not to intersect any part of the tubing String 53.
For mounting the actuating or control magnets on the exterior of the tubing string 53, a special connector nipple or tubular coupling 59, as seen in FIG. 5, may be employed. lts opposite ends are threaded for insertion within the tubing string and it has near one end an eX- terior locating shoulder 66 for a set of rings, sleeved one after the other on the outside of the body of the coupler 59. Such rings, as shown, include a pair of nonmagnetic collars 61-61, each having a series of disc or plug magnets 62 arranged in a circular row. Co-operating with the rings are a number of magnetic spacer collars 63 which can be variously sequentially positioned for changing the spaced relation selectively between the upper and lower nonmagnetic collars 61 for coding purposes. In addition, there is a longitudinally extended collar 64 of magnetic material which has circularly spaced elongated slots angularly spaced apart at about a forty-five degree angle. Within each vertical slot is located a nonmagnetic insert strip 65 for carrying a vertical row of spaced apart magnets v66. In this instance the magnetic lines of force between the opposite polarity end faces of the magnets pass through the nonmagnetic strip e and protrude into the space surrounding the tubing string S3. As seen in FIG. v6, the magnets are of frusto-conical rod shape and iit within outwardly tapered openings in the nonmagnetic strips 65 to insure retention. An end collar or ring 67 may carry a suitable set screw for fastening it securely to the coupler 59 and for maintaining the several rings in tight stacked relation one with another and with the uppermost ring against the stop shoulder 6i?.
When three magnetic switches in series connection, as
shown in FIG. 2C, are employed with the perforating gun, the magnets in the two rings 61-61 will supply fields to two of the switches and one row of magnets 66 will supply the field for the third magneto switch and whose field poles,V as previously described, are isolated in one side of the tool. Because of the impracticability of being able to set a long tubing string so that a given circular region thereof at a low point is certain to be at a given radial position, it is here proposed to provide the collar 64 with several vertical rows of magnets circularly spaced apart with a small enough intervening angle that one of the rows will present itself on the side of the tubing string 54 for co-operative relation with the isolated magnet poles of a gun brought into the firing region. This insures action of the perforator in a direction other than one which would pierce the tubing string 53.
What is claimed is:
l. Equipment for controlling directional well perforating operations, including a well tubing string member, a permanent magnet carried by said member at a selected side thereof with a pole thereof terminating at the member interior surface and establishing a magnetic held across a limited transverse Zone of said interior surface and transversely of the longitudinal direction of the member, a wire line suspended device for travel passage within the tubing string member, magneto means in said device, pole pieces therefor having terminal faces spaced apart transversely to its direction of travel passage and confined to a selected side zone in the peripheral face of the device for the extension of said magnetic held to the magneto means upon lateral alignment of said terminal faces with the magnetic field, a wire line suspending said device for travel and constituting a control through which said lateral alignment may be established, a perforating tool secured to said wire line suspended device, perforating means positioned on said tool for action in a restricted given lateral direction in fixed relation to the selected side zone location of said terminal faces and operating means for said perforating means connected with and influenced by said magneto means to actuate said perforatingmeans upon response of the magneto means to said magnetic field.
2. Equipment for controlling directional well perforating operations including a plurality of well tubing strings in side by side relation in the same well bore, a magnet carrying nipple located at a predetermined depth in one of the tubing strings, a magnet in said nipple having pole pieces isolated within a given sector of the nipple, a perforating tool adapted to be lowered through said one of the tubing strings, perforating means carried by the tool and directed for performing a perforating operation laterally thereof within a given circular segment of the tool, a magneto control operative to effect the action of said perforating means and mounted as a self-contained part of said tool, held poles for said magneto control terminated at the periphery of the tool and fixed in circular relationship to said given circular segment to compel relative tool adjustment into position in which the direction of perforating operation of said perforating means is away from intersecting relation with other tubing strings upon alignment of said field poles with the isolated pole pieces of said magnet and tool positioning means throughV which said tool adjustment is eected.
3. For the performance of directional well perforating operations, a well tubing string, a series of magnet carry- Y ing nipples at spaced apart depth intervals in the tubingy string, spaced apart pole pieces in each nipple in differently spaced apart relation in the several nipples for coded actuating relation with different well tools selectively, one of such tools being a perforating gun having an electrically actuated perforating charge mounted for projection in a predetermined direction, magneto devices controlling Vcharge actuating current flow to said charge and being carried by said gun, said magneto devices having pole pieces spaced apart in coded correspondence with the spaced apart relation of the magnet pole pieces of a selected one or" said nipples, the pole pieces of one of said magneto devices being in fixed angular relation to said predetermined direction of charge projection and a number of the last mentioned magnet pole pieces to which the pole pieces of said magneto device are coded being positioned by said selected one nipple for orienting the gun to a given charge projection direction relative to the said selected one nipple and gun positioning means operable to establish gun position for charge projection in said given direction.
4. In combination, a Well tubing string having a number of magnet carrying nipples at spaced apart depth intervals and with pole pieces spaced apart in coded relation to difierent well tools to be actuated in response to receipt thereby of magnetic lines of force, one of said nipples having its magnet pole pieces located for the presentation of lines of force only in an isolated side region of the nipple, a perforating gun for co-operation with the last mentioned nipple, a magneto device contained in the gun and provided with pole pieces isolated within one side of the gun to compel a given rotational position of the gun for iniiuencing said device by the magnetic lines of force through alignment of the pole pieces of the gun and the nipple, means operable on the gun and controlling said given rotational position and perforating means responsive to said magneto device and mounted by the gun to perform a perforating operation Within a zone fixed in relation to the isolated side location of the pole pieces of such magneto device.
5. For the actuation at selected levels of Well tools having magneto devices and pole pieces therefor variously spaced apart, a pair of tubing strings extending through a well hole, sets of magnets positioned in the tubing strings at predetermined depths and spaced apart in coded relation with pole pieces of certain well tools, one tubing string extending to a depth to produce from an upper formation and the other tubing string extending to a depth to produce from a lower formation, said other tubing string having sets of magnets exteriorly thereof and in a region in given relation to the upper formation, one of said sets of magnets comprising a number of vertical rows of vertically spaced apart magnets whose spaced apart relation is alike in all rows and which rows are angularly spaced apart so that regardless of rotational positions of said tubing string, there will be one of the several vertical rows of magnets adjacent a region longitudinally aligned with said one tubing string, a perforating gun to be lowered through said one tubing string to the level of the upper formation and having a laterally projectable charge and magneto means controlling the firing of said charge and having pole pieces arranged in sets which are spaced apart in coded correspondence to the sets of magnets which are exteriorly of said other tubing string, one of said sets of pole pieces being isolated in a side of the gun angularly spaced from the proiection path of said charge and gun suspension means operable to control gun position for presentation of the side isolated pole pieces Within the field of said one row of magnets.
References Cited in the file of this patent UNITED STATES PATENTS 2,282,431 Smith et al. May 12, 1942 2,419,468 Smith Apr. 22, 1947 2,632,959 Boucher Mar. 31, 1953 2,785,754 True Mar. 19, 1957 2,891,620 Bielstein June 23, 1959 2,938,584 Tausch et al May 31, 1960 3,032,107 Rumble et al May 1, 1962