Down-hole pump and inflatable packer apparatus

Abstract

A down-hole pump and inflatable packer apparatus for employment with tubular members in a well bore for isolating a desired zone or zones at one or more elevations in a well bore without the necessity of removing the apparatus from the well bore. The apparatus includes pump structure which employs a tubular pump piston longitudinally reciprocable within the apparatus in response to the rotation of a pump driving mandrel within the apparatus by the tubular members to which the apparatus is connected. The pump piston is operatively connected to the pump driving mandrel by means of cam follower lugs formed on the pump piston which are engaged with corresponding camming grooves or slots formed in the pump driving mandrel. The apparatus further discloses the employment of pump intake or exhaust check valve assemblies each employing a plurality of annular valve seal rings of substantially V-shaped cross-section and formed of relatively flexible material to form a one-way check valve structure.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to oil and gas well testing or treating and, more particularly, but not by way of limitation, to apparatus for isolating a zone in a well bore for testing or treating.

2. Description of the Prior Art

The prior art contains a number of teachings of down-hole pumps which are employed to inflate packers on a tubing string to isolate a zone or zones in a well bore. One form of known down-hole pump is actuated by the vertical reciprocation of the tubing string connected to the pump structure. Another known form of down-hole pump for this type ype of application is operated by rotation of the tubing string relative to the pump structure connected thereto.

The latter group of down-hole pumps which are operated by rotation of the tubing string includes pump structures which employ a plurality of vertically reciprocable pump pistons housed within the pump apparatus which each reciprocate within a corresponding close fitting pump cylinder. Such pump structures require precise machining and assembly and, in some cases, require the use of a special fluid carried with the apparatus, and isolated from the well fluid, for inflation of the packers. Such precisely machined and assembled pump structures are relatively expensive and are not susceptible to long operating life if well fluids near the isolated zone are to be employed for inflation of the packers due to the undesirable potentially damaging impurities carried by such well fluids.

SUMMARY OF THE INVENTION

The present invention contemplates a well tool adapted to be lowered on a tubular member into a well to isolate a zone in the well and of the type which includes a tubular upper housing assembly secured at its upper end in communication with the tubular member, a tubular lower housing assembly having an inflatable packer member mounted thereon, and a tubular mandrel assembly secured at its upper end in non-rotatable engagement with the upper housing assembly and with its lower end portion secured in rotatable engagement with the lower housing assembly. The tool includes an improved pump comprising an annular pump cavity carried within the tubular lower housing assembly formed between the inner periphery thereof an the outer periphery of the tubular mandrel assembly, and an annular pump piston longitudinally slidably disposed within the annular pump cavity. The pump intake passage is formed in the tubular lower housing assembly communicating between the annular pump cavity and a source of fluid. The pump includes intake check valve means positioned in the pump intake passage for permitting fluid flow through the intake passage to the annular pump cavity and preventing fluid flow through the intake passage in the opposite direction. A pump exhaust passage is formed in the tubular lower housing assembly communicating between the annular pump cavity and the interior of the inflatable packer member. The pump includes exhaust check valve means positioned in the pump exhaust passage for permitting fluid flow through the exhaust passage from the annular pump cavity to the interior of the inflatable packer member and preventing fluid flow through the exhaust passage in the opposite direction. The well tool includes means mutually engaging the tubular mandrel assembly, the lower housing assembly and the annular pump piston for imparting reciprocating motion to the annular pump piston within the annular pump cavity in response to rotation of the upper housing assembly and the tubular mandrel assembly relative to the lower housing assembly by the tubular member to pump fluid from the source of fluid into the interior of the inflatable packer member via the pump intake passage, intake check valve means, annular pump cavity, pump exhaust passage and exhaust check valve means to expand the inflatable packer member to isolate at least one zone in the well.

The following detailed description provides clear explanation of the construction details and the mode of operation of the down-hole pump and inflatable packer apparatus of the present invention.

Objects and advantages of the invention will be evident from the following detailed description when read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a elevation view illustrating the down-hole pump and inflatable packer apparatus of the present invention installed on a drill test string and positioned in a well bore prior to inflation of the packer elements to isolate a zone intersecting the well bore.

FIG. 2 is an elevation view similar to FIG. 1 illustrating the down-hole pump and inflatable packer apparatus as the packer elements are inflated to isolate the zone intersecting the well bore.

FIG. 3 is an elevation view similar to FIG. 2 ilustrating the down-hole pump and inflatable packer apparatus with the packer elements inflated to isolate the zone and with the drill test string conditioned to receive a test sample of well fluid from the isolated zone.

FIG. 4 is an elevation view similar to FIG. 3 illustrating the down-hole pump and inflatable packer apparatus with the packer elements inflated to isolate the zone and with the drill test string conditioned to halt the flow of well fluid from the isolated zone.

FIG. 5 is an elevation view similar to FIG. 1 illustrating the down-hole pump and inflatable packer apparatus as the packer elementss are deflated to release the sealing engagement with the well bore and terminate isolation of the zone intersecting the well bore.

FIGS. 6, 7 and 8 are vertical cross-sectional views of the upper, intermediate and lower portions of the down-hole pump and inflatable packer apparatus of the present invention, respectively, illustrating the relationship of the components thereof during inflation of the packers.

FIGS. 9 and 10 are vertical cross-sectional views of the upper and intermediate portions of the down-hole pump and inflatable packer apparatus of the present invention, respectively, illustrating the relationship of the components thereof during the performance of a flow test and preparatory to the release of pressure on the inflatable packers to deflate them.

FIGS. 11 and 12 are vertical cross-sectional views of the upper and intermediate portions of the down-hole pump and inflatable packer apparatus of the present invention, respectively, illustrating the relationship of the components thereof when pressure on the inflatable packers is released to deflate them.

FIG. 13 is a cross-sectional view taken along line 13--13 of FIG. 6.

FIG. 14 is a cross-sectional view taken along line 14--14 of FIG. 6.

FIG. 15 is a cross-sectional view taken along line 15--15 of FIG. 7.

FIG. 16 is a cross-sectional view taken along line 16--16 of FIG. 7.

FIG. 17 is a cross-sectional view taken along line 17--17 of FIG. 7.

FIG. 18 is a cross-sectional view taken along line 18--18 of FIG. 7.

FIG. 19 is a planar projection of the camming slots formed on the outer periphery of the pump mandrel of the present invention.

FIG. 20 is an enlarged fragmentary cross-sectional view of a portion of the intermediate portion of the down-hole pump illustrating construction details of the pump intake valve assembly.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawing, and to FIGS. 1-5 in particular, illustrated therein is the lowermost portion of a drill test string 10 comprising a plurality of tubular members positioned within a well bore 12. The well bore 12 is intersected by a zone 14 which is to be isolated by the apparatus of the present invention carried on the drill test string 10.

The illustrated portion of the lower end of the drill test string 10 includes a length of drill pipe 16 which, it will be understood, extends upwardly through the well bore 12 to the ground surface and may communicate with suitable drill collars and miscellaneous testing tools intermediate the ground surface and a suitable tester valve 18 which communicates at its upper end 20 with the lower end 22 of drill pipe 16. The lower end 24 of the tester valve 18 preferably communicates with a conventional hydraulic jar 26 at the upper end 28 thereof. The lower end 30 of the hydraulic jar 26 is connected in communication with a safety joint 32 at the upper end 34 thereof. The lower end 36 of the safety joint 32 is connected in communication with a down-hole pump and inflatable packer assembly 38 at the upper end 40 thereof.

A suitable device for employment as the tester valve 18 is disclosed in U.S. Pat. No. 2,740,479, which patent is incorporated herein by reference. This valve is operated by vertical movement of the drill test string 10 and is adapted to open the drill test string in response to the setting of string weight on the valve and, alternately, to close the drill test string to flow therethrough by slacking off the weight of the drill test string from the valve. The opening of the valve is resisted by the upward bias of the spring incorporated in the structure of the tester valve 18 which bias must be overcome by the weight of the drill string to open the valve. In certain applications it may be desirable to use a rotary action valve in the drill string above the valve 18 described above or in substitution therefor. Such a valve is disclosed in U.S. Pat. No. 3,152,644, which is incorporated herein by reference and used by Halliburton Services under the name Dual Closed-In-Pressure Valve.

A suitable hydraulic jar assembly for employment as the hydraulic jar 26 is disclosed in U.S. Pat. Nos. 3,339,740 and 3,429,389, incorporated by reference herein, and is manufactured and used by Halliburton Services under the registered trademark BIG JOHN and is further described and illustrated on pages 2556 and 2557 of the Halliburton Services Sales and Service Catalog, No. 37. The hydraulic jar 26 provides means for delivering an impact blow to the drill test string 10 in the event the test string becomes lodged in the well bore 12.

A suitable device for employment as the safety joint 32 is disclosed in U.S. Pat. No. 2,877,851, incorporated herein by reference, and is known commercially as the VR safety joint manufactured and used by Halliburton Services and further described and illustrated on page 2557 of the Halliburton Services Sales and Service Catalog, No. 37. The safety joint 32 provides means for separating the upper portion of the drill test string 10 from the down-hole pump and inflatable packer assembly 38 in the event the assembly 38 becomes lodged in the well bore 12.

Referring now to FIGS. 6, 7 and 8, the down-hole pump and inflatable packer assembly 38 will be described in detail. The assembly or tool 38 includes a tubular upper housing assembly 42 and a tubular lower housing assembly 44. The lower end portion 46 of the tubular upper housing assembly 42 and the upper end portion 48 of the tubular lower housing assembly 44 are interconnected in communication by means of a tubular torque mandrel 50 with the upper end portion 52 thereof received within the lower end portion 46 of the upper housing assembly 42, and with the lower end portion 54 thereof received within the upper end portion 48 of the lower housing assembly 44.

The upper housing assembly 42 comprises a cylindrically shaped body member 56 having an internally threaded portion 58 formed in the upper end portion 60 thereof for threaded engagement with the lower end 46 of the safety joint 32. A tubular mandrel 62 extends downwardly from the upper end portion 60 into a cavity 64 formed within the body member 56. The interior 66 of the mandrel 62 communicates with the outer periphery 68 of the body member 56 via a passageway 70 formed in the upper end portion 60 of the body member 56. A passageway 72 is formed within the upper end portion 60 of the body member 56 and provides communication between the cavity 64 nd the interior 73 of the safety joint 32 which communicates upwardly through the drill test string 10.

A left-hand, external buttress thread 74 is formed on the lower portion 76 of the mandrel 62 with the downwardly facing surface of the thread inclined upwardly and outwardly from the longitudinal axis mandrel 62. A cylindrical surface 78 is formed on the lower portion 76 of the mandrel 62 intermediate the external thread 74 and the lower end face 80 of the mandrel 62. The diameter of the cylindrical surface 78 is substantially equal to the root diameter of the thread 74. A cylindrical surface 82 is formed on the mandrel 62 and extends upwardly from the external thread 74.

A tubular ratchet case 84 is positioned within the cavity 64 and is received around the mandrel 62. An annular seal 86, such as an O-ring, is carried with the upper end portion 88 of the ratchet case and provides a sliding fluid-tight seal between the ratchet case and the cylindrical surface 82 of the mandrel 62. A plurality of ratchet blocks 90 are received in corresponding radially aligned apertures 92 extending through the cylindrical wall of the ratchet case 84. The apertures 92 are preferably circumferentially spaced about the ratchet case 84 with the radial axes thereof lying in substantially the same plane intersecting the longitudinal axis of the ratchet case. The inner surface of each ratchet block 90 carries a segment of a lefthand internal buttress thread 94 formed therein corresponding to and engageable with the external thread 74 of the mandrel 62. The upwardly facing surface of the internal thread segments 94 are inclined upwardly and outwardly relative to the longitudinal axis of the mandrel 62. The ratchet blocks 90 are biased radially inwardly relative to the ratchet case 84 and the mandrel 62 by means of one or more mandrel springs 96 encircling the ratchet blocks 90 an the ratchet case 84. Elastomeric O-rings of suitable size and strength are preferably employed as the annular spring 96 to bias the thread segments 94 of the ratchet blocks 90 into threaded engagement with the external threads 74 of the mandrel 62. The radially inward bias applied to the ratchet blocks 90 by the springs 96 may be overcome when sufficient downward force is applied to the mandrel 62 relative to the ratchet case 84 permitting these elements to move longitudinally together in telescoping fashion.

A tubular ratchet cover 98 is threadedly secured to the outer periphery of a ratchet case 84 and provides a fluid-tight seal between the apertures 92 in the ratchet case 84 and the cavity 64 of the body member 56 through sealing engagement with annular seals 100 and 102 carried by the ratchet case 84. When so assembled to the ratchet case 84, an annular downwardly facing shoulder 104 is provided by the ratchet cover 98 on the exterior of the ratchet case 84.

An inwardly extending annular shoulder 106 is formed within the body member 56 and extends into the cavity 64. Another inwardly extending annular shoulder 108 is formed on the body member 56 at the lower end portion 110 thereof. A plurality of longitudinal spline ribs 112 extend between the annular shoulders 106 and 108.

An outwardly extending annular shoulder 114 is formed on the upper end portion 52 of the torque mandrel 50 and is received within the cavity 64 of the body member 56 intermediate the annular shoulders 106 and 108 thereof. A plurality of longitudinal spline grooves 116 are formed in the annular shoulder 114 and slidably received the spline ribs 112 of the body member 56 therein thereby permitting relative longitudinal motion and preventing relative rotational motion between the body member 56 and the torque mandrel 50. A sliding fluid-tight seal is provided between the annular shoulder 108 of the body member 56 and the cylindrical outer periphery 118 by means of an annular seal 120 carried in the annular shoulder 108.

An upwardly facing annular shoulder 122 is formed on the upper end portion of the torque mandrel 50 and provides means for engaging the annular shoulder 104 carried by the ratchet case 84. The annular shoulder 122 is interrupted by one or more passgeways 124 formed in the upper end portion 52 to provide fluid passage therethrough when the annular shoulders 104 and 112 are engaged in abutment as will be explained further hereinafter.

A tubular release mandrel 126 is threadedly secured in fluid-tight communication at its upper end portion 128 to the lower end portion 130 of the tubular ratchet case 84. A plurality of downwardly extending lugs 131 are formed on the lower end portion 110 of the body member 56 for selective engagement with the lower housing assembly 44 as will be explained in detail hereinafter.

The tubular lower housing assembly 44 comprises an upper body assembly 132, a flow adapter 134, a lower body assembly 136 and a drag spring body assembly 138.

The torque mandrel 50 is received within the upper portion 140 of the upper body assembly 132. An outwardly extending annular flange 142 is formed on the torque mandrel 50 and is disposed intermediate an upper inwardly extending annular flange 144 and a lower inwardly extending annular flange 146 formed within the upper body assembly 132. An upper thrust bearing 148 is longitudinally disposed intermediate the annular flange 142 of the torque mandrel and the annular flange 144 of the upper body assembly. A lower thrust bearing 150 is longitudinally disposed intermediate the annular flange 142 of the torque mandrel and the annular flange 146 of the upper body assembly. A rotary fluid-tight seal is provided between the annular flange 144 and the cylindrical outer periphery 118 of the torque mandrel 150 by means of an annular seal 152 carried by the flange 144. A rotary fluid-tight seal is provided beween the flange 146 and the cylindrical outer periphery 154 of the torque mandrel 50 by means of annular seal 156 carried by the flange 146. A plurality of lug receiving grooves 158 are formed in the upper portion 140 of the upper body assembly 132 and are sized to receive the downwardly extending lugs 131 of the body member 56 therein in selective non-rotating engagement as will be described in more detail hereinafter.

A tubular pump mandrel 160 is threadedly secured in fluid-tight communication at its upper end portion 162 to the lower end portion 164 of the torque mandrel 50. A cylindrical outer surface 166 is formed on the upper portion 168 of the pump mandrel 160. An inwardly extending annular flange 170 is formed within the upper body assembly 132 and includes a cylindrical inner surface 172 formed thereon having a diameter greater than the diameter of the cylindrical outer surface 166 of the pump mandrel 160.

A tubular pump piston 174 is slidably disposed about the cylindrical outer surface 166 of the pump mandrel 160 radially intermediate the pump mandrel and the upper body assembly 132. The piston 174 includes a cylindrical inner surface 176 having a diameter slightly greater than the diameter of the cylindrical outer surface 166 of the pump mandrel thereby achieving a close longitudinal sliding relationship therebetween. A cylindrical outer surface 178 is formed on the lower portion of the piston 174 and has a diameter slightly less than the diameter of the cylindrical inner surface 172 of the annular flange 170 thereby also achieving a close longitudinal sliding relationship between the pump piston and the upper body assembly 132.

A sliding fluid-tight seal is achieved between the pump mandrel 160 and the pump piston 174 by means of a plurality of annular seals 180 carried by the pump mandrel in annular grooves formed therein. A plurality of annular seals 182 carried by the annular flange 170 in annular grooves formed therein provides a sliding fluid-tight seal between the annular flange 170 and the cylindrical outer surface 178 of the pump piston 174.

The seals 180 and 182 are preferably elastomeric O-rings, however other forms of annular seals may be employed if desired. A pair of longitudinal spline ribs 184 extend between the annular flanges 146 and 170 within the upper body assembly 132. Corresponding longitudinal spline grooves 186 are formed in the outer periphery of the pump piston 174 and are longitudinally slidably received around the spline ribs 184 to prevent relative rotation between the pump piston 174 and the upper body assembly 132 as shown in FIG. 13.

Upper and lower cam grooves or slots 188 and 190 are formed in the pump mandrel 160 intersecting the cylindrical outer surface 166 thereof. The contours of the cam grooves or slots 188 and 190 are clearly depicted in the planar projection of the pump mandrel illustrated in FIG. 19. Radially inwardly extending cam follower lugs 192 and 194 extend respectively into the cam grooves or slots 188 and 190. Each of the lugs 192 and 194 carries a cam follower bushing 196 journaled thereon which provides driving engagement between the pump mandrel 160 and the pump piston 174 whereby righthand rotation of the pump mandrel 160 relative to the upper body assembly 132 as indicated by arrow 197 in FIG. 19, causes a resulting longitudinal oscillation of the pump piston 174 between the annular seals 180 and 182 thus generating a pumping effect.

An annular intake valve cavity 198 is formed in the upper body assembly 132 and is spaced a longitudinal distance below the annular flange 170. A pump intake check valve asembly 200 is positioned and secured within the intake valve cavity 198 as shown in FIG. 20. The pump intake check valve assembly 200 comprises a plurality of valve seal rings 202 separated by a plurality of valve retainer rings 204. It will be seen in FIG. 20 that each valve seal ring 202 is substantially V-shaped in cross-section with outwardly and upwardly extending inner and outer wing portions 206 and 208 which are relatively flexible. The valve seal rings 202 may be suitably formed of an elastomeric or synthetic resin material. Each valve retainer ring 204 is substantially T-shaped in cross-section and is formed of a relatively rigid material such as steel. The inner and outer wing portions 206 and 208 of each valve seal ring 202 yieldably engage the inner cylindrical surface 210 and outer cylindrical surface 212 of the annular intake valve cavity 198 forming a one-way check valve structure. The lowermost valve retainer ring 204 is supported by an annular surface 214 forming a floor in the annular intake valve cavity 198 and interconnecting the inner and outer cylindrical surfaces 210 and 212. The valve seal rings 202 and valve retainer rings 204 are secured in vertically stacked array within the intake valve cavity 198 against the annular surface 214 by means of a downwardly extending annular flange 216 formed in the upper body assembly 132. The flange 216 includes a plurality of radially aligned ports 218 extending therethrough a provide a passageway for pumped fluid to pass through.

An annular fluid intake cavity 210 is formed in the upper body assembly 132 and is spaced a longitudinal distance below the annular intake valve cavity 198. A cylindrical wall 222 surrounds the cavity 220 and is penetrated by a plurality of radially aligned apertures 224 providing communications between the cavity 220 and the exterior of the upper body assembly 132. A suitable cylindrically shaped screen 226 is secured to the exterior of the upper body assembly 132 surrounding the cylindrical wall 222 and apertures 224 providing means for filtering undesirable material particles from well fluids which are drawn into the cavity 220 by the pumping action of the pump piston 174. A plurality of longitudinal ports 228 are formed in the upper body assembly 132 and extend between the fluid intake cavity 220 and the annular intake cavity 198 to provide fluid communication therebetween as shown in FIG. 14. A pressure equalization port 230 is formed in the upper body assembly 132 and communicates between the tubular pump piston 174 slidably disposed therein and the exterior thereof.

The upper body assembly 132 further includes a recessed cylindrical surface 231 formed on the outer periphery thereof longitudinally spaced below the fluid intake cavity 220. A second recessed cylindrical surface 234, having a diameter slightly greater than the cylindrical surface 232, extends downwardly from the surface 232 and communicates with the surface 232 via tapered annular surface 236. The upper end of cylindrical surface 232 communicates with the outer periphery of the upper body assembly 132 via an annular shoulder 238 formed in the upper body assembly. The lower end of cylindrical surface 234 communicates with the outer periphery of the body assembly 132 via annular shoulder 240. An annular pressure limit valve member 242 is slidably disposed about the surfaace 232, 234 and 236. The upper portion of the limit valve member 242 carries an annular seal 244 which slidingly sealingly engages the cylindrical surface 232. The lower portion of the limit valve member 242 carries an annular seal 246 which slidingly sealingly engages the cylindrical surface 234. A plurality of ports 248 are formed in the limit valve member 242 spaced longitudinally below the annular seal 246 and communicating between the outer periphery of the limit valve member and the inner periphery thereof adjacent to cylindrical surface 234. An annular cavity 250 is defined by the inner periphery of the limit valve member 242 intermediate the annular seal 244 and 246 and the surfaces 232, 234 and 236 on the outer periphery of the upper body assembly 132.

A plurality of ports 252 extend radially through the wall of the upper body assembly 132 and communicate between the cavity 250 and a cylindrical inner surface 254 formed within the upper body assembly 132. A compression coil spring 256 is disposed around the upper body assembly 132 intermediate the annular shoulder 238 and the upper end face of the limit valve member 242. The coil spring 256 biases the limit valve member 242 downwardly and against the annular shoulder 240. It will be understood that the limit valve member 242 will move upwardly against the bias of the coil spring 256 when fluid pressure acting through the ports 252 and cavity 250 on the cross-sectional area of the limit valve member 242 between the annular seals 242 and 246 overcomes the downward bias of the coil spring 256. The limit valve member 242 will communicate the interior of the upper body assembly 132 with the exterior thereof when sufficient pressure acts on the previously defined cross-sectional area between the annular seals 244 and 246. By proper selection of the spring rate of the coil spring 256 and the cross-sectional area of the limit valve member 242 between the annular seals 244 and 246, it will be seen that the maximum pressure to be applied by the pump relative to hydrostatic pressure in the annulus surrounding the drill test string 10 may be accurately predetermined.

An annular exhaust valve cavity 258 is formed in the upper body assembly 132 and is spaced a longitudinal distance below the limit valve member 242. A pump exhaust check valve assembly 260 is positioned and secured within the exhaust valve cavity 258. The pump exhaust check valve assembly 260 comprises a plurality of valve seal rings 262 separated by a plurality of valve retainer rings 264. The valve seal rings 262 are substantially identical to the valve seal rings 202 of the pump intake check valve assembly 200 described above except that the outer wing portions thereof are outwardly and downwardly extending as will be seen in FIG. 7. The valve seal rings 262 may be suitably formed of an elastomeric or synthetic resin material as may the valve seal rings 202. Each valve retaining ring 264 is substantially identical in material and configuration to the previously described valve retainer rings 204. The inner and outer wing portions of each valve seal ring 262 yieldably engage the inner cylindrical surface 266 and the outer cylindrical surface 268 of the exhaust valve cavity 258 forming a one-way check valve structure. The uppermost valve retainer ring 264 is supported by an annular surface 270 extending radially inwardly from the inner cylindrical surface 266. The valve seal rings 262 and valve retainer rings 264 are secured in vertically stacked array within the exhaust valve cavity 258 against the annular surface 270 by means of an upwardly extending annular flange 272 formed in the upper body assembly 132. The flange 272 includes a plurality of radially aligned ports 274 extending therethrough to provide a passageway for pumped fluid to pass through.

An annular passageway 276 is formed within the upper body assembly 132 and communicates at its upper end with the exhaust valve cavity 258 and at its lower end with the lower end face 278 of the upper body assembly 132. A tubular inflatable upper packer element or member 280 is disposed about the outer periphery of the upper body assembly 132. The upper end portion 282 of the upper packer element is secured to the outer periphery of the upper body assembly 132 providing an annular fluid-tight seal therebetween. The lower end portion 284 of the upper packer element is secured to an annular shoe 286 encircling the outer periphery of the upper body assembly 132 in fluid-tight engagement. The annular shoe 286 includes a cylindrical shaped inner surface 288 which slidingly engages a cylindrically shaped outer surface 290 formed on the upper body assembly 132. An annular seal 292 is carried by the annular shoe 286 and provides a sliding fluid-tight seal between the annular shoe 286 and the cylindrically shaped outer surface 290 of the upper body assembly 132. A plurality of ports 294 communicate between the annular passageway 276 and the annular space 296 between the outer surface 290 and the interior of the upper packer element 280. The upper packer element 280 may be suitably constructed of reinforced rubber or other synthetic material which will permit the upper packer element to expand when fluid is pumped from the pump exhaust check valve assembly 260 through the annular passageway 276 and ports 294 into the annular space 296. It will be understood that the annular shoe 286 is free to move upwardly relative to the upper body assembly 132 as the upper packer element 280 is inflated.

The upper body assembly 132 further includes a flow tube 298 which extends downwardly within the upper body assembly 132 from a position longitudinally adjacent to the upper packer element 280.

The flow tube 298 includes a cylindrical inner surface 300 and cylindrical outer surfaces 302 and 304 interconnected by conical outer surface 306. A radially outwardly extending annular flange 308 is formed on the lower end portion of the flow tube and communicates with the cylindrical outer surface 304. The annular flange 308 carries an annular seal 310 therein. An annular recess 312 is formed in the cylindrical inner surface 300 in the upper portion of the flow tube longitudinally adjacent to the cylindrical outer surface 302.

The lower end portion 314 of the release mandrel 126 extends downwardly within the flow tube 298. The cylindrical outer periphery 316 of the lower end portion 314 is slidably received within the cylindrical surface 300 of the flow tube. A sliding fluid-tight seal is achieved between the inner surface 300 of the flow tube and the outer periphery 316 of the release mandrel by means of annular seals 318 and 320 carried by the flow tube and disposed respectively above and below the annular recess 312. One or more ports 322 are formed in the lower end portion 316 of the release mandrel 126 and communicate between the outer pheriphery 316 and the longitudinal passage 324 extending through the release mandrel 126.

The release mandrel 126 includes a plurality of outwardly extending lugs 326 formed on the outer periphery 316 which longitudinally slidably engage a plurality of inwardly extending lugs 328 formed within the upper body assembly 132 which provide for longitudinal reciprocation of a release mandrel relative to the upper body assembly and prevent rotation of the release mandrel relative to the upper body assembly. A plurality of seals 330 are carried by the upper body assembly 132 and provide a rotary fluid-tight seal between the upper body assembly and the lower end portion 332 of the pump mandrel 160.

A tubular release port member 334 extends radially between the flow tube 298 and the upper body assembly 132. The port member 334 provides fluid communication between the annular recess 312 of the flow tube and the annular passageway 276 formed in the upper body assembly. Annular seals 336 and 338 provide fluid-tight seals between the port member 334 and the flow tube 298 and upper body assembly 132, respectively.

The flow adapter 134 is threadedly secured at its upper end portion to the lower end portion of the upper body assembly 132. Fluid-tight seals are achieved between the flow adapter and the upper body assembly by means of annular seals 340 and 342 carried by the flow adapter 134. An annular chamber 344 is formed in the upper end portion of the flow adapter 134 and communicates with the annular passageway 276 of the upper body assembly 132. A plurality of longitudinal passages 346 are formed in the flow adapter and communicate between annular chamber 344 and the lower end face 348 of the flow adapted. A cylindrically shaped inner surface 350 extends downwardly through the flow adapter communicating at the lower end portion thereof with the radially inwardly extending annular flange 352 carrying an annular seal member 354 therein. The annular seal 310 in the annular flange 308 of the flow tube 298 sealingly engages the inner surface 350 of the flow adapter 134. A plurality of radially extending ports 356 communicate between the inner surface 350 and the outer periphery 358 of the flow adapter 134.

A tubular spacer member 360 of predetermined length threadedly secures the lower end portion of the flow adapter 134 to the upper end portion of the lower body assembly 136. Suitable fluid-tight seals are achieved between the spacer member 360 and the upper and lower body assembly 132 and 136 by means of annular seals 362 and 364 carried by the upper and lower body assemblies, respectively. A tubular inner spacer member 366 of predetermined length extends between the lower portion of the upper body assembly and the upper portion of the lower body assembly. An outwardly extending annular flange 368 is formed on the inner spacer member 366 and longitudinally positions the inner spacer member between the lower end face 348 of the upper body assembly 132 and the upper end face 370 of the lower body assembly 136. Fluid-tight seals are achieved between the inner spacer member 366 and the upper and lower body assemblies by means of the annular seal member 354 carried in the annular flange 352 of the upper body assembly and by means of an annular seal 372 carries in the upper end portion of the lower body assembly. An annular space 374 is formed between the inner spacer member 366 and the tubular spacer member 360 and between the lower end face 348 of the upper body assembly 132 and the upper end face 370 of the lower body assembly 136.

A tubular inflatable lower packer element or member 376, substantially identical in construction to the upper packer element 280 described above, is disposed about the outer periphery of the lower body assembly 136. The upper end portion 378 of the lower packer element is secured to the outer periphery of the lower body assembly 136 providing an annular fluid-tight seal therebetween. The lower end portion 380 of the lower packer element is secured to an annular shoe 382 encircling the outer periphery of the lower body assembly 136 in fluid-tight engagement. The annular shoe 382 includes a cylindrically shaped inner surface 384 which slidingly engages a cylindrically shaped outer surface 386 formed on the lower body assembly 136. An annular seal 388 is carried by the annular shoe 382 and provides a sliding fluid-tight seal between the annular shoe anad the cylindrically shaped outer surface 386 of the lower body assembly 136. It will again be understood that the annular shoe 382 is free to move upwardly relative to the lower body assembly 136 as the lower packer element 376 is inflated.

An annular space 390 is formed in the lower body assembly 136 adjacent to the upper end portion 378 of the lower packer element 376. A plurality of longitudinal passages 392 extend from the upper end face 370 to the annular space 390 providing fluid communication between the annular space 374 and an annular space 394 between the outer surface 386 of the lower body assembly 136 and the interior of the lower inflatable packer element 376.

The lower end portion 396 of the lower body assembly 136 is theadedly secured to the upper end portion 398 of the drag spring body assembly 138. A fluid-tight seal is achieved between the lower body assembly and the drag spring body assembly by means of an annular seal 400 carried by the drag spring body assembly. An equalizer tube 402 is carried within the lower body assembly 136 and the upper end portion 398 of the drag spring body assembly 138. A fluid-tight seal is achieved between the outer periphery of the upper end portion 404 of the equalizing tube and the lower body assembly 136 by means of an annular seal 406 carried by an inwardly extending annular flange 408 formed within the lower body assembly. A fluid-tight seal is achieved between the upper end portion 398 of the drag spring body assembly 138 and the outer periphery of the lower end portion 410 of the equalizing tube 402 by means of an annular seal 412 carried by a radially inwardly extending annular flange 414 formed within the drag spring body assembly 138. A cavity 416 formed within the drag spring body assembly 138 communicates with the lower end portion 410 of the equalizing tube 402 and further communicates with the outer periphery 418 of the drag spring body assembly by means of a radially aligned port 420 extending between the cavity 416 and the outer periphery 418.

An annular chamber 422 is defined within the lower body assembly 136 and the drag spring body assembly 138 and is defined by the outer periphery 424 of the equalizing tube 402, the inner periphery 426 of the lower body assembly and the inner peripheral surface 428 of the drag spring body assembly intermediate the annular seals 406 and 412. A radially extending port 430 is formed in the lower body assembly 136 and communicates between the annular chamber 422 and the outer periphery 432 of the lower body assembly.

A longitudinal cavity 434 is formed in the drag spring body assembly 138 and communicates with the lower end face 436 thereof. The cavity 434 is sized and shaped to receive a suitable pressure recording device 438 therein such as the Halliburton BT Pressure Recording Device illustrated and described on page 2549 of the Halliburton Services Sales and Service Catalog Number 37. The cavity 434 may be closed and the pressure recording device 438 secured therein by means of a threaded end cap 440 which may be threadedly secured to the lower end portion 442 of the drag spring body assembly 138. A suitable fluid-tight seal is achieved between the end cap 440 and the lower end portion 442 of the drag spring body assembly by means of a suitable annular seal 444 carried by the end cap. A longitudinal passage 446 is formed in the drag spring body assembly 138 and communicates between the annular chamber 422 at the inner peripheral surface 428 of the drag spring body assembly and the cavity 434 formed within the drag spring body assembly.

A plurality of bowed drag springs 448 are secured in circumferentially spaced relation about the outer periphery of the drag spring body assembly 138. The upper and lower ends 450 and 452 of each drag spring 448 are preferably longitudinally slidably secured to the outer periphery of the drag spring body assembly in recesses 454 and 456 formed respectively therein.

OPERATION

In describing the operation of the present invention, particular reference will be made to FIGS. 1-5. The down-hole pump and inflatable packer assembly 38 is assembled to the lower end portion of a drill test string 10 in a manner as described above and illustrated in FIGS. 1-5. The drill test string 10 is lowered into the well bore 12 until the flow adapter 134 of the assembly 58 is positioned a distance below the zone 14 which is to be isolated by the apparatus of the present invention. The drill test spring 10 is then raised within the well bore 12 until the zone 14 is positioned intermediate the inflatable upper and lower packer elements 280 and 376 with the flow adapter 134 adjacent to the zone 14. By raising the drill string 10 within the well bore 12 to position the assembly 38 relative to the zone 14, the various elements of the assembly 38 are longitudinally extended and assume the relative positions illustrated in FIGS. 11 and 12.

Right-hand rotation is then applied to the drill string 10 thereby rotating the tubular upper housing assembly 42, the torque mandrel 50, and the pump mandrel 160 relative to the tubular lower housing assembly 44 which is secured against rotation within the well bore 12 through the engagement of the drag springs 448 with the wall of the well bore 12. The rotation of the pump mandrel 160 relative to the upper body assembly 132 of the tubular lower housing assembly 44 causes a resulting vertical reciprocation of the tubular pump piston 174 within the upper body assembly 132. When the tubular pump piston 174 moves upwardly relative to the upper body assembly 132 on the intake stroke, well fluid is drawn through the screen 226, ports 224, fluid intake cavity 220 and ports 228 into the through the pump intake check valve cavity 198 past the valve seal rings 202 of the pump intake valve assembly 200 into an annular chamber or pump cavity 454 in the upper body assembly 132. When the tubular pump piston 174 is driven downwardly relative to the upper body assembly 132 the well fluids in the annular chamber or pump cavity 454 are prevented from flowing back into the well bore 12 by the check valve action of the valve seal rings 202 of the pump intake check valve assembly 200, and the well fluids within the annular chamber 454 are forced downardly therefrom through an annular passageway 456 formed in the upper body assembly 132 into and through the exhaust valve cavity 258 and the valve seal ring 252 of the pump exhaust check valve assembly 260 into annular passageway 276. Pumped well fluid passes from the annular passageway 276 through the ports 294 into the annular space 296 to inflate the inflatable upper packer element 280. The pumped well fluid also passes from the annular passageway 276 into the annular space 394 between the outer surface 386 of the lower body assembly 136 and the interior of the lower inflatable packer element 376 to inflate the packer element 376 via the annular chamber 344 and passages 346 in the flow adapter 134, the annular space 374 formed between the inner spacer member 366 and the tubular spacer member 360, and the passages 392 and annular space 390 formed in the lower body assembly 136. Pressurized well fluid is prevented from flowing upwardly through the pump exhaust check valve assembly 60 through the check valve action of the valve seal rings 262 thereof.

It will also be seen that, as the drill test string 10 is rotated, the tubular mandrel 62 of the upper housing assembly 42 rotates relative to the ratchet case 84 and the release mandrel 126 secured thereto. The ratchet case 84 and release mandrel 126 are prevented from rotating relative to the lower housing assembly 44 by the engagement between the outwardly extending lugs 326 of the release mandrel 126 and the inwardly extending lugs 328 of the upper body assembly 132. The threaded engagement between the ratchet blocks 90 carried by the ratchet case 84 with the left-hand external buttress thread 74 formed on the tubular mandrel 62 causes the ratchet case 84 and release mandrel 126 to move downwardly relative to the upper housing assembly 42 and the lower housing assembly 44 in response to the relative rotation therebetween. This downward movement of the release mandrel 126 relative to the lower housing assembly 44 and the flow tube 298 thereof causes the ports 322 in the release mandrel to move below the annular seal 320 carried by the flow tube 298 as illustrated in FIG. 6 thus providing a closed fluid system between the pump exhaust check valve assembly 260 in the interiors of the upper and lower inflatable packer elements 280 and 376 as clearly shown in both FIGS. 7 and 10. The ratchet case 84 will continue to move downwardly relative to the mandrel 62 in response to the relative rotation therebetween until the lefthand internal buttress thread segments 94 of the ratchet blocks 90 run out of the external thread 74 of the mandrel 62 onto the cylindrical surface 78 on the lower portion 76 of the mandrel 62. At this point the release mandrel 126 will move no further downwardly in response to additional rotation between the upper housing assembly 42 and the lower housing assembly 44.

Continued rotation of the upper housing assembly 42 relative to the lower housing assembly 44 after the ports 322 of the release mandrel 126 have moved below the annular seal 320, thus blocking fluid communication between the annular passageway 276 and the longitudinal passage 324 through the release mandrel 126 via the tubular release port member 334, will cause the upper and lower inflatable packer elements 280 and 376 to be inflated to sealingly engage the wall of the well bore 12 thereby isolating the zone 14 as shown in FIG. 2. When the predetermined maximum differential pressure between the fluid in the packer elements 280 and 376 and the hydrostatic pressure in the annulus between the drill test string 10 and the well bore 12 at the packer elements is reached and exceeded, further operation of the tubular pump piston 174 will cause the limit valve member 242 to move upwardly against the bias of the coil spring 256 thereby relieving excess fluid pressure within the packer elements to the annulus via the ports 252 in the upper body assembly 132 and the ports 248 in the limit valve member 242. It should also be noted that the hydrostatic pressure above and below the inflatable packer elements 280 and 376 is equalized through the down-hole pump and inflatable packer assembly 38 via the passageway 70 in the body members 56 of the upper housing assembly 42 and the port 420 of the drag spring body assembly 138 which are in fluid communication through the interior 66 of the mandrel 62, the interior of the ratchet case 84, the longitudinal passage 324 through the release mandrel 126, the interior of the flow tube 298, the interior of the tubular inner spacer member 366, the interior of the equalizer tube 402, and the cavity 416 formed in the drag spring body assembly 138.

When the packer elements 280 and 376 are fully inflated, isolating the zone 14, rotation of the drill test string 10 is terminated thereby stopping operation of the pump. Fluid communication between the isolated zone 14 and the interior 73 of the safety joint 32 and the remainder of the drill test string 10 thereabove through the assembly 38 is provided via the ports 356 in the flow adapter 134, the annular space 458 between the flow tube 298 and the upper body assembly 132 and flow adapter 134, the annular space 460 between the release mandrel 126 and the upper body assembly 132, the annular space 462 between the pump mandrel 160 and the release mandrel 126, an annular space 464 between the torque mandrel 50 and the release mandrel 126 and ratchet case 84, and the cavity 64 and passageway 72 in the body member 56. The tester valve 18 in the drill test string 10 is opened by setting string weight on the tester valve 18 and on the assembly 38. This action causes the upper and lower housing assemblies 42 and 44 of the assembly 38 to telescope together as illustrated in FIGS. 3, 9 and 10. After the upper and lower housing assemblies 42 and 44 have telescoped together, the tester valve 18 will then be caused to telescopically contract by the application of additional string weight as shown in FIG. 3 causing the tester valve 18 to open to fluid flow therethrough thereby placing the isolated zone 14 in communication with the drill test string 10 above the tester valve 18. It will be seen in FIG. 9 that the lugs 131 of the upper housing assembly 42 are received in the grooves 158 of the lower housing assembly 44 thereby preventing relative rotation therebetween. When the lugs and grooves 131 and 158 are so engaged, the drill test string 10 above the assembly 38 may be rotated to operate other tools above the assembly 38. This capability of the present invention may be particularly valuable when it is desired to manipulate the safety joint 32 to separate the drill test string 10 from the assembly 38 in the event the assembly 38 becomes lodged in the well bore 12 and cannot be removed by manipulation of the drill test string 10.

By lifting up on the drill test string 10 a predetermined amount, the tester valve 18 may be telescopically extended to close it to fluid flow therethrough while still retaining sufficient string weight on the assembly 38 to retain it in the telescopically collapsed position as illustrated in FIG. 4.

It will be seen in FIG. 9 that when the upper and lower housing assemblies 42 and 44 of the down-hole pump and the inflatable packer assembly 38 are telescopically collapsed, as further illustrated in FIGS. 3 and 4, the annular shoulder 104 on the ratchet cover 98 of the ratchet case 84 abuts the annular shoulder 122 on the torque mandrel 50. The mandrel 62 of the upper housing assembly 42 moves telescopically downwardly relative to the ratchet case 84 and the ratchet blocks 90 are moved relatively upwardly on the external buttress thread 74 overcoming the bias of the annular springs 96, with the internal buttress thread segments 94 thereof threadedly engaged again with the external buttress thread 74.

When it s desired to deflate the inflated packer elements 280 and 376, the drill test string 10 is lifted upwardly in the well bore 12 until the upper and lower housing assemblies 42 and 44 are fully telescopically extended as illustrated in FIGS. 5, 11 and 12. It will be seen in FIGS. 11 and 12 that, when the upper and lower housing assemblies 42 and 44 are fully telescopically extended, the ratchet case 84 and release mandrel 126 move upwardly with the upper housing assembly 42 and the ports 322 of the release mandrel 126 are moved into registration with the annular recess 312 intermediate the annular seals 318 and 320 of the flow tube 298. This positioning of the release mandrel 126 allows the pressurized well fluid within the inflated packer elements 280 and 376 to communicate through the release port member 334, annular recess 312 and ports 322 into the longitudinal passage 324 through the release mandrel 126 which in turn communicates with the annulus above and below the packer elements 280 and 376 via the passageway 70 and the port 420 as described above.

The previously described operation of the present invention may be repeated a number of times for isolating various zones intersecting the well bore 12 without the necessity of removing the drill test string 10 from the well bore 12. The relatively simple mechanism employed in the down-hole pump and inflatable packer assembly 38 provides a pump structure of economical construction which, owing to its simple design, is well suited for pumping abrasive laden well fluids to inflate the packer elements.

It should be clearly understood that the present invention, though disclosed as employing a down-hole pump in conjunction with spaced inflatable packer elements, will be equally advantageous when employed as a down-hole pump in conjunction with a single inflatable packer element. It should also be noted that the basic construction of the down-hole pump is suitable for other down-hole applications other than the inflation of inflatable packer elements when drill string rotation is to be employed as the motive force for driving the pump structure.

Changes may be made in the combination and arrangement of the parts or elements as heretofore set forth in the specification and shown in the drawings without departing from the spirit and scope of the invention as defined by the following claims.

Claims

What is claimed is:

1. A down-hole pump and inflatable packer tool adapted to be lowered on a tubular member into a well for isolating at least one zone in the well, comprising:

a tubular upper housing assembly having an upper end portion and a lower end portion and positioned below the tubular member;

means for securing the upper end portion of said upper housing to the tubular member in communication therewith;

a tubular lower housing assembly positioned below said upper housing assembly and having an upper end portion and a lower end portion;

a tubular mandrel assembly having an upper end portion and a lower end portion with the upper end portion thereof secured in communication with the lower end portion of said upper housing assembly in nonrotatable, longitudinal sliding engagement therewith, and with the lower end portion thereof in communication with the upper end portion of said lower housing assembly in rotatable engagement therewith;

an annular pump cavity formed within said tubular lower housing intermediate the inner periphery thereof and the outer periphery of said tubular mandrel assembly;

an annular pump piston longitudinally slidably disposed within said annular pump cavity;

a pump intake passageway in said lower housing assembly communicating between said annular pump cavity and the exterior of said lower housing assembly;

intake check valve means disposed in said pump intake passageway for permitting fluid flow from the exterior of said lower housing assembly through said intake passageway to said annular pump cavity and, alternately, preventing fluid flow through said intake passageway in the opposite direction;

inflatable packer means carried by said lower housing assembly for expanding to seal against the wall of the well to isolate at least one zone in the well in response to the application of fluid pressure to the interior thereof;

a pump exhaust passageway in said lower housing assembly communicating between said annular pump cavity and the interior of said inflatable packer means;

exhaust check valve means disposed in said pump exhaust passageway for permitting fluid flow from said annular pump cavity through said exhaust passageway to the interior of said packer means and, alternately, preventing fluid flow through said exhaust passageway in the opposite direction; and

means mutually interconnecting said tubular mandrel assembly, said annular pump piston and said lower housing assembly for inparting longitudinal reciprocal motion to said annular pump piston within said annular pump cavity in response to rotation of said upper housing assembly relative to said lower housing assembly by the tubular member to pump fluid from the well into said inflatable packer means through said pump intake passageway and intake check valve means and said pump exhaust passageway and exhaust check valve means to expand said inflatable packer means against the wall of the well to isolate at least one zone in the well.

2. The down-hole pump and inflatable packer tool as defined in claim 1 characterized further to include:

means connected to the tool for achieving a fluid-tight seal between said annular pump cavity and said inflatable packer means in response to rotation of said upper housing assembly by the tubular member relative to said lower housing assembly; and

means connected to the tool for releasing the fluid-tight seal between said annular pump cavity and said inflatable packer means in response to longitudinal reciprocation of said upper housing assembly by the tubular member relative to said lower housing assembly to release fluid pressure within said inflatable packer means.

3. The down-hole pump and inflatable packer tool as defined in claim 2 characterized further to include:

passage means in said tool for communicating the interior of said inflatable packer means to the well when the fluid-tight seal between said annular pump cavity and said inflatable packer means is released.

4. The down-hole pump and inflatable packer tool as defined in claim 1 characterized further to include:

passage means in the tool for communicating the isolated zone in the well with the tubular member.

5. The down-hole pump and inflatable packer tool as defined in claim 4 characterized further to include:

pressure recorder means carried by the tool for recording fluid pressures in the isolated zone; and

passage means in the tool for providing fluid communication between the isolated zone and said pressure recorder means.

6. The down-hole pump and inflatable packer tool as defined in claim 1 characterized further to include:

means carried by said lower housing assembly for engaging the wall of the well to prevent the rotation of said lower housing assembly relative to the well in response to rotation of said upper housing assembly by the tubular member.

7. A down-hole pump and inflatable packer tool adapted to be lowered on a tubular member into a well for isolating at least one zone in the well, comprising:

a tubular upper housing assembly having an upper end portion and a lower end portion and positioned below the tubular member;

means for securing the upper end portion of said upper housing in communication with the tubular member;

a tubular lower housing assembly positioned below said upper housing assembly and having an upper end portion and a lower end portion;

a tubular mandrel assembly having an upper end portion and a lower end portion with the upper end portion secured in communication with the lower end portion of said upper housing assembly in non-rotatable longitudinal sliding engagement therewith and with the lower end portion secured within and in communication with the upper end portion of said lower housing assembly in rotatable engagement therewith;

an annular pump cavity formed within said tubular lower housing intermediate the inner periphery thereof and the outer periphery of said tubular mandrel assembly;

an annular pump piston longitudinally slidably disposed within said annular pump cavity;

a pump intake passageway in said lower housing assembly communicating between said annular pump cavity and the exterior of said lower housing assembly;

intake check valve means in said pump intake passageway for permitting fluid flow from the exterior of said lower housing assembly through said intake passageway to said annular pump cavity and, alternately, preventing fluid flow through said intake passageway in the opposite direction;

longitudinally spaced inflatable packer means carried by said lower housing assembly for expanding to seal against the wall of the well to isolate at least one zone in the well in response to the application of fluid pressure to the interiors thereof;

a pump exhaust passageway in said lower housing assembly communicating between said annular pump cavity and the interiors of said spaced inflatable packer means;

exhaust check valve means in said pump exhaust passageway for permitting fluid flow from said annular pump cavity through said exhaust passageway to the interiors of said spaced inflatable packer means and, alternately, preventing fluid flow through said exhaust passageway in the opposite direction; and

means mutually interconnecting said tubular mandrel assembly, said annular pump piston and said lower housing assembly for imparting longitudinal reciprocal motion to said annular pump piston within said annular pump cavity in response to rotation of said upper housing assembly relative to said lower housing assembly by the tubular member to pump fluid from the well into said inflatable packer means through said pump intake passageway and intake check valve means and said pump exhaust passageway and exhaust check valve means to expand said spaced inflatable packer means against the wall of the well to isolate at least one zone in the well.

8. The down-hole pump and inflatable packer tool as defined in claim 7 characterized further to include:

means connected to the tool for achieving a fluid-tight seal between said annular pump cavity and said spaced inflatable packer means in response to rotation of said upper housing assembly by the tubular member relative to said lower housing assembly; and

means connected to the tool for releasing the fluid-tight seal between said annular pump cavity and said spaced inflatable packer means in response to longitudinal reciprocation of said upper housing assembly by the tubular member relative to said lower housing assembly to release fluid pressure within said spaced inflatable packer means.

9. The down-hole pump and inflatable packer tool as defined in claim 8 characterized further to include:

passage means in said tool communicating the interiors of said spaced inflatable packer means to the well when the fluidtight seal between said annular pump cavity and said spaced inflatable packer means is released.

10. The down-hole pump and inflatable packer tool as defined in claim 7 characterized further to include:

passage means in the tool for communicating the isolated zone in the well with the tubular member.

11. The down-hole pump and inflatable packer tool as defined in claim 7 characterized further to include:

passage means in the tool for communicating the isolated zone in the well intermediate said longitudinally spaced inflatable packers with the tubular member.

12. The down-hole pump and inflatable packer tool as defined in claim 11 characterized further to include:

pressure recorder means carried by the tool for recording fluid pressures in the isolated zones; and

passage means in the tool for providing fluid communication between the isolated zone and said pressure recorder means.

13. The down-hole pump and inflatable packer tool as defined in claim 7 characterized further to include:

means carried by said lower housing assembly for engaging the wall of the well to prevent the rotation of said lower housing assembly relative to the well in response to rotation of said upper housing assembly by the tubular member.

14. In a well tool adapted to be lowered on a tubular member into a well for isolating a zone in the well and of the type which includes a tubular upper housing assembly secured at its upper end in communication with the tubular member, a tubular lower housing assembly having an inflatable packer member mounted thereon, and a tubular mandrel assembly secured at its upper end in non-rotatable engagement with the upper housing assembly and with its lower end portion secured in rotatable engagement within the lower housing assembly, an improved pump comprising:

an annular pump cavity carried within the tubular lower housing assembly formed between the inner periphery thereof and the outer periphery of the tubular mandrel assembly;

an annular pump piston longitudinally slidably disposed within said annular pump cavity;

a pump intake passage in the tubular lower housing assembly communicating between said annular pump cavity and a source of fluid;

intake check valve means in said pump intake passage for permitting fluid flow through said intake passage from the source of fluid to said annular pump cavity and preventing fluid flow through said intake passage in the opposite direction;

a pump exhaust passage in the tubular lower housing assembly communicating between said annular pump cavity and the interior of the inflatable packer member;

exhaust check valve means in said pump exhaust passage for permitting fluid flow through said exhaust passage from said annular pump cavity to the interior of the inflatable packer member and preventing fluid flow through said exhaust passage in the opposite direction; and

means mutually engaging the tubular mandrel assembly, the lower housing assembly and said annular pump piston for imparting reciprocating motion to said annular pump piston within said annular pump cavity in response to rotation of the upper housing assembly and the tubular mandrel assembly relative to the lower housing assembly by the tubular member to pump fluid from the source of fluid into the interior of the inflatable packer member via said pump intake passage, intake check valve means, annular pump cavity, pump exhaust passage and exhaust check valve means to expand the inflatable packer member to isolate at least one zone in the well.

15. The well tool as defined in claim 14 characterized further to include:

valve means connected to the tool for providing a fluid-tight seal between said annular pump cavity and the interior of the inflatable packer member in response to rotation of the upper housing assembly by the tubular member relative to the lower housing assembly, and, alternately, for releasing the fluid-tight seal between said annular pump cavity and the interior of the inflatable packer member in response to longitudinal reciprocation of the upper housing assembly by the tubular member relative to the lower housing assembly to release fluid pressure within the inflatable packer member.

16. The well tool as defined in claim 15 characterized further to include:

passage means in the tool for communicating the interior of the inflatable packer member to the well when the fluid-tight seal between said annular pump cavity and the inflatable packer member is released by said valve means.

17. The well tool as defined in claim 14 characterized further to include:

passage means in the tool communicating said pump intake passage with the exterior of the lower housing assembly to communicate with well fluids in the well.

18. The well tool as defined in claim 14 wherein said intake check valve means is characterized further to include:

an annular intake valve cavity having inner and outer walls and formed in said pump intake passage; and

at least one annular valve seal ring secured within said annular intake valve cavity, said valve seal ring being substantially V-shaped in cross-section with outwardly extending relatively flexible wing portions yieldably engaging the inner and outer walls of said intake valve cavity.

19. The well tool as defined in claim 18 wherein said exhaust check valve means is characterized further to include:

an annular exhaust valve cavity having inner an outer walls and formed in said pump exhaust passage; and

at least one annular valve seal ring secured within said annular exhaust valve cavity, said valve seal ring being substantially V-shaped in cross-section with outwardly extending relatively flexible wing portions yieldably engaging the inner and outer walls of said exhaust valve cavity.

20. The well tool as defined in claim 19 wherein said intake check valve means is characterized further to include:

an annular intake valve cavity having inner and outer walls and formed in said pump intake passage; and

at least one annular valve seal ring secured within said annular intake valve cavity, said valve seal ring being substantially V-shaped in cross-section with outwardly extending relatively flexible wing portions yieldably engaging the inner and outer walls of said intake valve cavity.