US3398803A

US3398803A - Single trip apparatus and method for sequentially setting well packers and effecting operation of perforators in well bores

Info

Publication number: US3398803A
Application number: US618736A
Authority: US
Inventors: Leutwyler Kurt; Jr Waldo W Henslee
Original assignee: Baker Oil Tools Inc
Current assignee: Baker Hughes Oilfield Operations LLC
Priority date: 1967-02-27
Filing date: 1967-02-27
Publication date: 1968-08-27
Anticipated expiration: 1985-08-27

Description

Aug. 27, 1968 K. LEUTWYLER ET AL 3,398,803

SINGLE TRIP APPARATUS AND METHOD PoR SEQUENTIALLY SETTING WELL PAcKERs AND EFFECTING OPERATION 0F PEEPoRAToRs IN wELL BoREs Filed Feb. 27, 1967 3 Sheets-Sheet l rrae/vEs/s.

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SINGLE TRIP APPARATUS AND METHOD FOR SEQUENTIALLY SETTING WELL PACKERS AND EFFECTING OPERATION OF PERFORATORS IN WELL BORES Filed Feb. 27, 1967 5 Sheets-Sheet 2 124.215. 'aga. G l

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Aug. 27, 1968 K. LEUTWYLER ET AL 3,398,803

SINGLE TRIP APPARATUS AND METHOD FOR SEQUENTIALLY SETTING WELL PACKERS AND EFFECTING OPERATION OF PERFORATORS IN WELL BORES Filed Feb. 27, 1967 3 Sheets-Sheet 3 INvE/vroes. K027- LEuTws/LER ,T4/Loo WHENSLEE J2..

5y ml United States Patent O SINGLE TRIP APPARATUS AND METHOD FOR SEQUENTIALLY SETTING WELL PACKERS AND EFFECTING OPERATION OF PERFORATORS IN WELL BORES Kurt Leutwyler and Waldo W. Henslee, Jr., Houston,

Tex., assignors to Baker Oil Tools, Inc., City of C0111- merce, Calif., a corporation of California Filed Feb. 27, 1967, Ser. No. 618,736 26 Claims. (Cl. 17S-4.52)

ABSTRACT OF THE DISCLOSURE A well packer, setting tool and perforating gun run together in a cased well `bore on a wire line, the setting tool setting the packer and being released from it, after which the perforating -gun can be placed in its desired location and fired to perforate the casing.

The present invention pertains to subsurface well apparatus and methods, and more particularly to well packers (including bridge plugs) to Ibe set in the well bore and perforators run in the well -bore in conjunction therewith for perforating tubular conduits disposed in the well bore, such as casing strings.

Heretofore, a well packer, such as a production packer or a bridge plug, has been run in a well bore on a wire line and set therewithin by means of a -setting tool that can be of the type which generates gas at an increasing pressure, the setting tool being released from the well packer after the latter has been set in the casing. The setting tool is then withdrawn and a perforating gun lowered on a Wire line to the desired location at which perforations are to be shot through the well casing. The necessity for making two separate round trips with the wire line equipment, to perform the setting of the well packer, and for then perforating the well casing, is time consuming and costly. In addition, it imposes additional wear on the relatively costly wire line, occasioned -by the necessity for making a separate trip in the Well bore to effect perforation of the well casing.

In accordance with the present invention, a well packer, setting tool therefor, and perforating gun are run as a unit in the well casing on a wire line. The setting tool is actuated to effect the setting of the well packer, as by closing an electric circuit to the setting tool, the perforating gun being, at this time, in an ineffective condition and incapable of being tired. After the well packer has been set, the setting tool is released from it, which will permit the perforating gun to be placed in the position in the well casing at which the latter is to be perforated, after which the circuit to the perforating gun is completed to effect its tiring and production of the casing perforations. Accordingly, by virtue of the present invention, the setting of the well packer in the well casing and the perforating of the casing at any desired point therewithin can 'be accomplished with a single run of the equipment in the well casing, thus effecting substantial economies in performing the combined operation in the well casing. The perforation gun is conditioned for firing only after the well packer has been set in the well bore, and, preferably, only after the setting tool used in setting the 'well packer has been released from the latter.

This invention possesses many other advantages and has other purposes which may be made more clearly apparent from a consideration of several forms and methods embodying the invention. These forms and methods are shown and described in the present specification and in the drawings accompanying and constituting a part thereof, they will now be described in detail, for

3,398,803 Patented Aug. 27, 1968 the purpose of illustrating the 4general principles of the invention; but it is to be understood that such detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined `by the appended claims.

Referring to the drawings:

FIGURES la and lbtogether constitute a longitudinal section through a well packer, setting tool, and perforating gun combination, illustrated in somewhat diagrammatic form, all of the parts being secured to one another and in their initial condition for downward movement in the well casing to the desired operating location, FIG. lb -being a lower continuation of FIG. la;

FIGS. 2a and 2b are views corresponding to FIGS. la and 1b, illustrating the well packer anchored in packedoff condition in the well casing, with the perforating gun still in its ineffective or inoperable condition, FIG. 2b being a lower continuation of FIG. 2a;

FIG. 3 is a diagrammatic view of the circuitry extending from the top of the well bore to the setting tool for the well packer and to the perforating gun;

FIG. 4 is a view similar to FIG. 3 showing a modified form of circuitry for the well packer, setting tool and perforating gun.

As disclosed in the drawings, a well packer A, shown specifically as of the bridge plug type, is releasably connected to a setting tool B. which is, in turn, secured to a perforating gun C, the perforating gun being attached to a wire line cable D extending to the top of the Well bore, and by means of which the combination of apparatus is lowered through a well casing E (or other tubular conduit string) in the well bore to the desired locations at which the well packer is to be set and the perforating operation performed. The cable D has an electrical conductor F within it, which extends to a service truck H, such as a perforating truck, located at the top of the well bore.

The well packer A, its setting tool B, and perforating gun C are illustrated generally diagrammatically in the drawings, since they are individually known mechanisms. It is the manner of their interrelation and control which provides the novel and patenta'ble features in the present case. The well packer A and setting tool B combination may be of the type illustrated in U.S. Patents Nos. 2,640,547, 2,637,402 and 2,653,666.. The perforating gun C may -be of any suitable type, such as one capable of shooting bullets or shaped charges through the casing E, as desired.

Specifically, the Well packer A includes a body 10 on which are mounted a plurality of upper slips 11 engaging an upper expander 12, the upper expander engaging the upper portion of a packing sleeve or packing structure 13 surrounding the body. The packing sleeve or structure 13, in turn, has its lower portion engaging a lower expander 14 that contacts a set of lower slips 1S bearing against an upwardly facing body shoulder 16. The upper and lower slips 11, 15, as well as the packing sleeve or packing structure 13', are initially disposed in retracted condition with respect to the packer lbody 10, the slips being held releasably in such retracted condition in any known manner. Relative longitudinal movement between the upper slips 11 and upper expander 12 effects shifting of the upper slips outwardly against the well casing; whereas, relative longitudinal movement between the lower expander 14 and lower slips 15 effects outward expansion of the lower slips against the well casing. Movement of the upper expander 12 and lower expander 14 toward each other results in shortening of the elastomer packing sleeve 13 and its expansion into sealing engagement with the wall of the well casing E.

The setting of the well packer A results from relative upward movement of the body 10 of the tool and relative downward movement of an upper thrust ring 17 slidable on the body and engaging the upper slips 11. The setting tool B, which is more specifically described in the above-identified United States patents, includes a cylinder 18 that has a piston 19 slidable therein. A piston rod 20 extends through a lower cylinder head 21 and is connected to a cross-piece 22 extending through a cross-slot 23 in the rod, the cross-piece being suitably attached to a setting ring 24 threadedly secured to a setting sleeve 25 engaging the thrust ring 17. The crosspiece 22 extends through a pair of longitudinal slots 25a in a tension mandrel 26 threadedly secured to the cylinder head 21, and also threadedly attached to a coupling 27, which is, in turn, threadedly secured to a tension rode 28 extending into the packer body 10. The lower end of the tension rod 28 is secured to a disruptable tension stud 29 threadedly attached to the transverse wall 30 of the body 10 of the bridge plug or well packer. This disrupta'ble stud has a central weakened section 31 at which it can pull apart as a result of a predetermined upward tensile force being imposed upon the cylinder 18, tension mandrel 26, coupling 27 and tension rod 28.

The cylinder 18 contains a power charge or propellant 32 ot' a known type adapted to be ignited by a flame emanating from an igniter 33, which will cause the power charge to gradually burn away and generate gas at an increasing pressure, to lforce the piston 19 downwardly in the cylinder 1S and the cylinder relatively upwardly of the piston in effecting setting of the Well packer A against the wall of the. well casing E. The igniter is mounted in a firing head 34 threadedly secured to a control switch body 35 threadedly attached to the upper portion of the cylinder 18, clamping a lower flange 36 of the firing head between the control switch body and the cylinder. This switch body 35 has its upper portion threadedly secured to a coupling 37 attached to the lower portion of the body 38 of a suitable perforating gun C having a cable head 39 threadedly attached thereto, to which the wire line cable D is suitably secured (in a known manner), the latter extending to the top of the well bore and to ya winding drum (not shown) on the perforating truck H located at the well site. v

The perforating gun C has a plurality of perforating elements 40 therein, such as bullets or shaped charges, fired by a prima cord 4,1, the prima cord being ignited by a suitable igniter 42 which is rendered effective upon passage of an electric current therethrough.

The igniter 33 for the power charge 32 in the setting tool is also ignited by the passage of an electric current through its lament 43. The current will flow from a suitable power or current source 84 in the perforating truck H through the conductor F of the wire cable D, which is connected to an arm `44 of a microswitch 45 disposed in the control body 35 interconnecting the cylinder 18 and coupling 37. Normally, this switch arm 44 engages a setting tool contact 46 having a line 47 running to one end of the setting tool igniter filament 43, its other end being grounded` As shown more specifically in FIG. 1a, the line running to the igniter filament 43 extends to a suitable contact 48 mounted -in an insulating sleeve 49 clamped between the firing head 34 and the switch body 35. Another contact 50 of the microswitch 45 has a line 51 running to one end of the igniter 42 for the prima cord 41, the other end of the igniter lbeing connected to ground.

The circuit to the prima cord igniter 42 is initially opened, as disclosed in FIG. 3, and is only closed after the well packer A has been set, the setting tool B released therefrom, and the perforating gun C and released setting tool B shifted to the location in the well casing E at which the perforating operation is to take place. In the form of invention disclosed in FIGS. 1 to 3, inclusive, current c`an pass to the perforating gun igniter 42 only atter a predetermined pressure 'has been generated in the cylinder 18, which is substantially in excess of the pressure necessary to disrupt the stud 29 and release the setting tool B from the set bridge plug A. Even then, the current to the prima cord igniter 42 will only pass upon proper operation of a switch 52 in the perforating truck H, the switch including a switch arm 53 connected to the power or current source 44, one end of the power source being connected to ground. This switch 52 is normally open and, when engaging the contact 54 connected to the c'able conductor F, wi-ll first complete the circuit to the setting tool igniter filament 43. When ignition of the power charge 32 occurs, the switch arm 53 can be shifted by the operator to an open condition.

As disclosed in FIGS. l to 3, inclusive, the microswitch will condition the perforating gun igniter 42 for the reception of current from the perforating truck H not only after a predetermined pressure has been developed in the cylinder 18 as a result of burning away of the power charge 32. As shown, the chamber 55 in the cylinder and its firing head 34 can be rendered communicable with a cylinder 56 in the -switch body 35 through a uid lpressure passage 57. The lower portion of this cylinder 56 has a disc 58 extending thereacross, whic-h is rupturable at a predetermined unit pressure substantially in excess of the pressure necessary to pull the disrupta'ble stud 29 apart at its weakened section 31. Above the rupture disc 58, a piston or plunger 59 is mounted in the cylinder 56 which is adapted to engage the switch arm 44 upon disruption of the disc, the pressure shifting the piston 59 upwardly and the arm 44 upwardly into engagement with the perforating gun contact 50, thereby conditioning the perforating gun igniter 42 for reception of current from the perforating truck H.

Fluid pressure leakage between the chamber 55 and the uid pressure passage 57 is prevented by suitable side seal rings 60 mounted on the firing head 34 and engaging the Wall of the body 35 on the opposite side of the passage 57. Similarly, fluid pressure leakage from the cylinder 18 is prevented by one or a plurality of seal rings 61 on the firing head engaging the cylinder, by a seal ring 62 on the setting tool piston 19 engaging the wall of the cylinder 18, yand by a rod seal 63 on the cylinder head 21 Slidably and sealing engaging the piston rod 20. Oil may be located initially in a space 64 between the rupture disc 58 and the piston or plunger S9, leakage past the plunger being prevented by a seal ring 65 thereon sealingly engaging the wall of its confining cylinder 56.

In the use of the apparatus illustrated in FIGS. 1 to 3, inclusive, the switch 52 in the perforating truck is at rst in an open condition, the microswitch 45 being disposed in the condition shown in FIG. 3. The disruptable stud 29 1s intact, the upper and lower slips 11, 15 and the packing sleeve 13 being initially in their retracted position. All of the parts are in the conditions disclosed in FIGS. la and 1b. The apparatus A, B, C is lowered on the wire line cable or running-in string D in the well casing E until the location is reached at which the well packer or bridge plug A is to be set. The truck switch 52 is then closed, which will direct current from the source 84 to the filament 43 of the setting tool ignited 33, the igniter firing and the ame therefrom igniting the upper end of the power charge 32, which will gradually burn away and develop an increasing pressure in the cylinder 18. This pressure will force the piston 19 downwardly in the cylinder 18 and will relatively shift the cylinder in an upward direction, eie-cting downward movement of the setting sleeve 25 and relative upward movement of the tension mandrel 26, coupling 27, tension rod 28, disruptable stud 29, and body 10. The setting sleeve 25 bears upon the thrust ring 17 and shifts it relatively downwardly along the body 10, which will effect downward shifting of the upper slips 11 along the upper expander 12, the lower slips 15 along the lower expander 14, and of the upper and

lower expanders

12, 14 toward each other, to expand the slips 11, 15 against the well casing and the packing sleeve 13 against the well casing E, anchoring the well packer A in packedoff condition in the well casing. The increasing pressure in lthe cylinder 18, resulting from the continuing burning away of the power change 32, insures a firm seal of the packing sleeve 13 against the casing and a firm anchoring of the slips 11, 15 thereagainst. As the tension imposed on the tension stud 29 increases, it will eventually reach a value that will disrupt if at its weakened section 31 to release the setting tool B from the well packer A, the well packer remaining in its anchored and packed-off condition in the well casing. As set forth in U.S. Patent No. 2,653,666, the thrust ring 17 may have a split lock ring 68 therein, which will engage the body 10 of the tool and prevent upward movement of the thrust ring 17 along the body, thereby retaining the well packer slips 11, 15 and packing sleeve 13 in their expended conditions.

As the pressure in the cylinder 18 increases, it is also acting through the fluid passage 57 on the rupture di-sc 58. However, this disc has such strength as to resist rupturing until a pressure is reached substantially in excess of the pressure necessary to break the disruptable stud 29 at its weakened section 31. As an example, the disruptable disc or plate 58 will not break until a pressure of about 10,000 p.s.i. is reached in the cylinder 18 and in the fluid pressure passage S7; whereas, the pressure in the cylinder 18 necessary to disrupt the stud 29 at its weakened section will be about 7,500 p.s.i.

After the stud 29 disrupts, the piston 19 wi-ll shift downwardly in its cylinder 18 to its lowermost position, the power charge 32 continuing to burn away and increasing the pressure in the cylinder 18 to a greater extent. When the pressure reaches a value sufficient to rupture the disc 58, the latter is broken and the fluid pressure than acts through the hydraulic oil in the cylinder 56 upon the piston 59 in the control switch body 35, shifting the latter upwardly and moving the microswitch arm 44 from its position engaging the setting tool igniter contact 46 to its position in engagement with the perforating gun contact 50. However, before lthis occurs, the switch 52 in the perforating gun truck has been -shifted to an open condition. Thus, the perforating gun is merely conditioned to receive current, but it will not receive current until the switch 52 is reclosed.

The gun C and setting tool B are then elevated above the set bridge plug A to a location at which perforations are to be produced through the wall of the well casing E and in the surrounding formation. When this location is reached, the switch 52 in the perforating truck i-s again closed, sending current through the igniter 42, which will effect burning ofthe prima cord 41 and firing of the perforating elements 40 into and through the well casing. The perforating gun C and setting tool B attached thereto can now be elevated through the casing E to the top of the well bore through the expedient of reeling in the wireline cable D.

In the form of invention disclosed in FIG. 4, a polarity switch 70 is used in the control switching body mechanism 35 in place of the pressure activated switch 45 illustrated in FIG. 3. In the truck H at the top of the well bore, a selector switch 71 is provided, which can include a switch arm 72 adapted to be swung into engagement with a contact 73 connecting the conductor F of the cable to the positive pole of a power source 74, the negative pole of which is connected to ground, or the switch arm 72 can be shifted into engagement with a contact 75 connected to the negative pole of a power source 76, the positive pole of which is connected to ground. The cable conductor F extends to the polarity switch 70 which takes the place of the pressure actuated switch 45, this polarity switch including two blocking diodes 77, 78 connected to the conductor F. The conductor F is connected to the positive pole of a blocking diode 77, the negative side of which is connected to the igniter 43 for the power charge 32 of the setting tool B. -It is also connected to the negative pole of the other blocking diode 78, the positive pole of whicl is connected to the igniter 42 of the perforating gun In the use of the combination of apparatus employing the polarity switch disclosed in FIG. 4, the selector switch 71 is at first in an open condition; that is, it is disconnected from both

power sources

74, 76. After the combination of apparatus A, B, C disclosed in FIGS. 1a and 1b has been lowered to the location in the well casing at which the bridge plug A is to be set, the selector switch arm 72 is shifted into engagement with the contact 73 of the first power source 74, which will then cause current to ow through the blocking diode 77 and the igniter filament 43, the igniter 33 firing and causing the power charge 32 to burn away thereby causing the setting tool B to set the bridge plug or packer A in the manner described above, the disruptable stud 29 finally breaking at its weakened section 31 to free the setting tool B from the anchored and sealed olf bridge plug A. The perforating gun C and setting tool B are then shifted to the desired location in the well casing above the set well packer A at which the perforating operation is to be performed, whereupon the selector switch arm 72 is moved into engagement with the contact 75 of the other power source 76, which will cause current to flow through the conductor F and the other blocking diode 78 to the igniter 42 for the prima cord 41 of the perforating gun, the perforating charges being fired and the bullets or shaped charges 40 being caused to penetrate the well casing E to perforate the same. Following the perforating operation, the perforating gun C and setting tool B can be removed from the well casing through the expedient of reeling in the wire line cable D at the top of the well bore.

-It is apparent that a combination well packer and perforating 'gun has been provided that can be run in a Well bore at the same time on a wire line, the well packer A being set at a desired location through the passage of current through its igniter 33, such current being prevented from passing through the -igniter 42 of the perforating gun. yIt is only after the setting tool B has been released from the bridge plug A following its anchoring in sealed condition against the wall of the well casing that the perforating gun can be conditioned for performing its #perforating operation. Such perforating operation is conducted at the desired location in the well casing and at the will of the operator; that is, the operator can perform the 'perforating operation at any time after the Ibridge plug A has been set, the setting of the bridge plug or rwelll packer and the firing of the perforating gun C being independent of one another as to location, and also as to the time interv-al elapsing between the setting of the bridge plug and the firing of the perforating gun.

We claim:

1. In apparatus to be lowered on a running-in string in Ia conduit disposed in a well bore: a well tool having normally retracted means expandable into engagement with the conduit; a setting tool releasably secured to said Well tool for expanding said normally retracted means against the conduit; a perforator device secured to said setting tool for perforating the conduit; means for effecting operation of said setting tool to expand said normally retracted means against said conduit and to release said setting tool from said well tool without operating said perforator device; and means for effecting operation of said perforator device after release of said setting tool from said welll tool.

2.In apparatus as defined in claim 1; wherein said well tool is a well packer having normally retracted packing means expanded by said setting tool against the conduit.

3. In apparatus las ydefined in claim 1; wherein said well tool is a well packer having normally retracted packing means and normally retracted slip means,said packing means and slip means being expanded by said setting tool against the conduit.

4. In apparatus as ldefined in claim 1; wherein said means for effecting operation of said setting tool and for effecting operation of said perforator device comprises electric circuit means extending -to the top of the well bore; means for closing the circuit for said setting tool while said circuit for said perforator 'device remains open; and means for closing the circuit for said perforator device after release of said setting tool from said well tool.

5. In apparatus as defined in claim 1; wherein said means for effecting operation of said setting tool and for efiecting operation of said perforator device comlprises electric circuit means extending to the top of the well bore; means for closing the circuit for said setting tool while said circuit `for said perforator device remains open; and means responsive to operation of said setting tool for enabling the circuit to said perforator device to be closed after release of said setting tool from said well tool.

`6. In apparatus yas defined in claim 1; wherein said well tool is a well packer having normally retracted packing means and normally retracted slip means, said packing means and slip means bein-g expanded by said setting tool against the conduit; said means for effecting operation of sai-d setting tool and for effecting operation of said perforator d'evice comprising electric circuit means extending to the top of the well bore; means for closing the circuit for said setting tool while said circuit for said perforator device remains open; and means responsive to operation of said setting tool for enabling the circuit for said perforator device to be closed after release of said setting tool from said well tool.

7. In apparatus to be lowered on a running-in string in a conduit disposed in a well bore: 'a well tool having normally retracted means expandable into engagement with the conduit; a setting tool releasably secured to the well tool for expanding said normally retracted means against the conduit, said setting tool being of the type having an ignitable propellant therein for generating a gas at increasing pressure and also having: an igniter for igniting said ipropellant; a perforator device secured to said setting tool for perforating the conduit, said perforator device -being of the type having one or more explosive char-ges for perforating the conduit and also having ignition means for said one or more charges; means for tiring said igniter to ignite said propellant without operating said ignition means; and means for operating said ignition means to fire said one or more charges after release of said setting tool from said well tool.

8. In apparatus as defined in claim 7; wherein said means for firing said igniter and ignition means comprises electric circuit means; means for closing the circuit to said igniter while said circuit to said ignition means remains open; and means for conditioning the circuit to said ignition means for closing after release of said setting tool from said well tool.

9. In apparatus as ldefined in claim 7; wherein said means for firing said igniter and ignition means cornprises elec-tric circuit means; means for closing the circuit to said igniter while said circuit to said ignition means remains open; and switch means responsive to the pressure generated 'by said propellant in said setting tool for conditioning the circuit to said ignition means for closing.

10. In apparatus as defined in claim 7; wherein said means for tiring said igniter and ignition means comprises electric circuit means; means for closing the circuit to said igniter while circuit to said ignition means remains open; switch means responsive to the pressure generated by said propellant in said setting tool for conditioning the circuit to said ignition means for closing; said switch means being inoperative to condition said circuit to said ignition means for closing until said pressure reaches a value exceed-ing the pressure required to release said setting tool from said well tool.

11. In apparatus as defined in claim 7; wherein said means for firing said igniter and ignition means comprises electric circuit means extending through the runningin string to the top of the well bore; switch means at the top of the well bore for closing the circuit to said igniter while said circuit to said ignition means remains open; and means for conditioning the circuit to said ignition means for closing after release of said setting tool from said well tool.

12. In apparatus as deiined in claim 7; wherein said means for firing said igniter and ignition means comprises electric circuit means extending through the running-in string to the top of the -well bore; switch means at the top of the well 'bore for closing the circuit to said igniter while said circuit to said ignition means remains open; and switch means responsive to the pressure generated by said propellant in said setting tool for conditioning the circuit t-o said ignition means for closing.

13. In apparatus as defined in claim 7; wherein said means for firing said igniter and ignition means comprises electric circuit means extending through the running-in string to the top of the well bore and including a polarity switch connected to said igniter and ignition means; selector means at the top of the well bore for passing current from the top of the well bore through said circuit means of a polarity to be conducted through said polarity switch to said igniter, said selector means being Ioperative -to pass current from the top of the well bore through said circuit means of opposite polarity to be conducted through said polarity switch to said ignition means 14. In apparatus as dened in claim 7; wherein said means for firing said igniter and ignition means comprises electric circuit means extending through the running-in string to the top of the well rbore and including a polarity switch connected to said igniter and ignition means; selector means at the top of the well bore for passing current from the top of the `well bore through said circuit means of a polarity to be conducted through said polarity switch to said igniter, said selector means being operative to pass current from the top of the well bore through said circuit means of opposite polarities to be conducted through said polarity switch to said ignition means; said polarity switch comprising a blocking diode of one polarity connected to said igniter and a blocking diode of opposite polarity connected to said ignition means.

1S. In a method of setting a well tool in a conduit disposed in a well bore and of perforating the conduit: the steps of lowering a well tool and a perforator device as a unit in the conduit to a setting location; setting the well tool at the setting location and releasing the perforator device from the lwell tool without actuating the perforator device; placing the perforator device at a perforating location in the conduit; and operating the perforator device to perforate the conduit.

16. In a method of setting a -well tool in a conduit disposed in a well bore and of perforating the conduit: the steps of providing an assembly of a setting tool releasably secured to a well tool and also attached to a perforator device; lowering the assembly in the conduit on a wire line to a setting location; effecting operation of the setting tool to cause the setting tool to set the well tool at the setting location and to release the setting tool from the well tool; placing the perforator device at a perforating location in the conduit; and operating the perforator device to perforate the conduit.

17. In a method as defined in claim 16; including the step of elevating the wire line in the conduit to withdraw the perforator device and setting tool from the conduit after the conduit has been perforated.

18. In a method as dened in claim 16; wherein said setting tool is operated by passing electric current through the Iwire line to said setting tool; operation of said perforator device being effected by passing electric current through the wire line to said perforator device; current fbeing passed to said setting tool before current is passed to said perforator device.

19. In a method as dened in claim 16; wherein said setting tool is operated Iby passing electric current through the wire line to said setting tool; operation of said perforator device being eifected by passing electric current through the wire line to said perforator device; holding the electric circuits to the setting tool and perforator device in initially opened conditions; closing the circuit to said setting tool while retaining the circuit to said perforator device in opened condition; and closing the circuit to said perforator device after release of said setting tool from the well tool.

20. In apparatus to be lowered on a running-in string in a conduit disposed in a well bore: well tool apparatus embodying a structure having normally retracted means expandable into engagement with the conduit; a perforator device releasably related to said structure for perforating the conduit; means for effecting operation of said well tool apparatus to expand said normally retracted means against said conduit and to disassociate said perforator device from said structure without operating said perforator device; and means for effecting operation of said perforator device after disassociation of said perforator device from said structure.

21. In apparatus as defined in claim 29; wherein said means for effecting operation of said well tool apparatus and for effecting operation of said perforator device comprises electric circuit means extending to the top of the well lbore; means for closing the circuit for said well tool apparatus while said circuit for said perforator device remains open; and means for closing the circuit for said perforator device after disassociation of said perforator device from said structure,

22. In apparatus as defined in claim 20; wherein said means for effecting operation of said well tool apparatus and for effecting operation of said perforator device comprises electric circuit means extending to the top of the well bore; means for closing the circuit for said well tool apparatus while said circuit for said perforator device remains open; and means responsive to operation of said well tool apparatus for enabling the circuit to said perforator device to be closed after disassociation of said perforator device from said structure.

23. In apparatus to be lowered on a running-in string in a conduit disposed in a well bore: well tool apparatus embodying a structure having normally retracted means expandable into engagement with the conduit, said well tool apparatus embodying setting means of the type havmg an ignitable propellant therein for generating a gas at increasing pressure and also having an igniter for igniting said propellant; a perforator device releasalbly related to said structure for perforating the conduit, said perforator device being of the type having one or more explosive charges for perforating the conduit and also having ignition means for said one or more charges; means for firing said igniter to ignite said propellant without Operating said ignition means; and means for operating said ignition means to tire said one or more charges after disassociation of said perforator device from said structure.

24. In apparatus as defined in claim 23; wherein said means for ring said igniter and ignition means comprises electric circuit means; means for closing the circuit to said igniter while said circuit to said ignition means remains open; and means for c-onditionng the circuit to said ignition means for closing after disassociation of said perforator device from said structure.

25. In apparatus as defined in claim 23; wherein said means for firing said igniter and ignition means comprises electric circuit means; means for closing the circuit to said igniter while said circuit to said ignition means remains open; and switch means responsive to the pressure generated by said propellant in said setting means for conditioning the circuit to said ignition means for closing.

26. In apparatus as defined in claim 23; wherein said means for firing said igniter and ignition means comprises electric circuit means extending through the running-in string to the top of the well bore and including a polarity switch connected to said igniter and ignition means; selector means at the top of the well bore for passing current from the t-op of the well bore through said circuit means of a polarity to be conducted through said polarity switch to said igniter, said selector means being operative to pass current from the top of the well bore through said circuit means of opposite polarity to be conducted through said polarity switch to said ignition means.

References Cited UNITED STATES PATENTS 2,839,142 6/1958 Huiber 166-35 2,965,031 12/1960 Johns 166-55 2,986,214 5/1961 Wiseman 175-4.52 3,064,733 1l/l962 Bourne 166-63 3,187,813 6/1965 Greene l6663 3,266,575 8/1966 Owen.

JAMES AA. LEPPINK, Primary Examiner.