Downhole well tool valve

Abstract: A packer perforate, test and sample tool includes a tester valve (10) which is positioned above a well packer (28) and which has a bypass which provides communication between a well annulus above the packer and a firing mechanism (36) for guns (34) positioned below the packer. When the well annulus pressure is raised, the firing mechanism is triggered. The bypass may be closed prior to firing of the guns, and after perforation, a valve in the tester valve may be opened to flow a sample of well fluid into a sampling chamber (20) located above the tester valve.

Description: This invention relates to a valve for use above a packer in a well testing string, and to a downhole well tool incorporating such a valve. Well testing operations are commonly conducted on oil and gas wells in order to determine production potential and to enhance the same if possible. In flow testing a well, a tester valve is lowered into the well on a string of drill pipe above the packer. After the packer is set, the tester valve is opened and closed periodically to determine formation flow, pressure and rapidity of pressure recovery. One such downhole tool which is capable of performing in different modes of operation as a drill pipe tester valve, a circulation valve and a formation tester valve, as well as providing the operator with the ability to displace fluids in the pipe string above the tool with nitrogen or other gas prior to testing or retesting, is disclosed in our U.S. patent specification no. 4,633,952 (Ringgenberg). This tool is also described in Halliburton Service Sales and Service Catalog No. 43, page 2548 as the Omni ® circulating valve. Another similar circulating valve is disclosed in our U.S. specification no. 4,657,082 (Ringgenberg). As indicated, the Omni ® circulating valve can be used as a tester valve, but is not adapted for use with pressure actuated time delay firing means for guns below a packer because the valve does not have a bypass which provides communication between the well annulus above the packer and the components of the tool string below the packer. Preferably, formation testing is carried out by running a tool string into the well bore once, making the test, and removing the tool string. Tester valves positioned below packers have been utilized to perform such tests, but these devices are relatively complex. Accordingly, there is a need for a simplified testing system. EP-A-0288239 discloses a downhole tool for use with a tool string in a well bore, comprising: guns for perforating a well formation in said well bore; firing means for firing said guns; a packer disposed above said guns and said firing means for isolating said formation from an upper well annulus position above the said packer; and a valve comprising housing means for connecting to said tool string, said housing means defining a substantially longitudinally extending central opening therethrough; bypass means on said housing means for providing communication between said central opening and a well annulus portion above said packer, whereby annulus pressure can be communicated to a tool string portion below said packer in use of the valve, said bypass means having selectable open and closed positions; and valve means disposed above said bypass means in said housing means for providing communication between said central opening and a portion of said tool string above said housing means. The tool of the present invention is mainly characterised in that the tool further comprises a sample chamber disposed above the packer and that the said valve means comprises an axially sliding valve selectively disposable between open and closed positions, the valve being in communication with the sampling chamber, and that the sliding valve means, when in open position connects the well formation to the sampling chamber for the chamber to be filled with a sample of fluid, and that actuating means are provided for selectively opening and closing said bypass means and said valve means alternately and closing both together. The valve disclosed in EP-A-0288239 is not a tester valve but serves merely as a means for firing a time-delay firing device to trigger a perforating gun. It employs a hollow ball valve so as to minimise flow restrictions through the tool when the valve is open. Also, the valve operating mechanism is arranged so that the ball valve and the bypass valve are opened and closed alternately. Compared with EP-A-0288239, the valve of the present invention is designed for use as a tester valve and is characterised in that the said valve means comprises an axially sliding valve selectively displaceable between respective open and closed positions and the valve includes actuating means for selectively opening and closing the bypass means and the said valve means alternately and closing both together. The invention also includes a valve for use in the downhole tool of the invention, the said valve comprising: housing means for connecting to said tool string, said housing means defining a substantially longitudinally extending central opening therethrough; bypass means on said housing means for providing communication betweeen said central opening and a well annulus portion above said packer, whereby annulus pressure can be communicated to a tool string portion below said packer in use of the valve, said bypass means having selectable open and closed positions; and valve means disposed above said bypass means in said housing means for providing communication between said central opening and a portion of said tool string above said housing means, charaterised in that the said valve means comprises an axially sliding valve selectively displaceable between open and closed positions and actuating means for selectively opening and closing said bypass means and said valve means alternately and closing both together. A preferred embodiment of the present invention will now be more particularly described by way of example and with reference to the accompanying drawings in which: FIGS. 1A and 1B show a schematic view of one embodiment of perforate, test and sample tool of the present invention on a tool string positioned in a well bore; FIGS. 2A-2G show a partial longitudinal cross section of an embodiment of tester valve of the tool; FIG. 3 is a view taken along lines 3-3 in FIG. 2E showing the pattern of a ratchet used in the tester valve; and FIG. 4 illustrates a cycle chart showing the various positions of the tester valve and a sequence of operation. Referring now to FIGS. 1A and 1B, the embodiment of tester valve of the perforate, test and sample tool of the present invention is shown and generally designated by the numeral 10. Tester valve 10 forms a part of a tool string 12 positoned in a well bore 14. Typically, a bull plug 16, an upper drain sub 18, a sample chamber 20, a gauge carrier 22 and a lower drain sub 24 are positoned above tester valve 10. All of these components are of a kind generally known in the art. Below tester valve 10 are a safety joint 26, hydraulic circulating valve (if desired), a casing packer 28, a tubing pup joint 30 and a flow check valve 32. Below check valve 32 are perforating guns 34 with a firing means 36 disposed thereabove. The firing means 36 is preferably a TDF (time-delayed firing) differential delay firer. Below perforating guns 34 are blank guns 38 and a gauge carrier 40. All of these components below tester valve 10 are also of a kind generally known in the art. As will be discussed in more detail herein, tool string 12 is positoned such that perforating guns 34 are adjacent to a well formation 42 which is to be tested. Perforating guns 34 are adapted for perforating well casing 44 and formation 42 so that fluid may be flowed from the formation for testing and so a sample may be taken. Referring now to FIGS. 2A-2G, the details of tester valve 10 will be discussed. As seen in FIG. 2A, the outer portion of tester valve 10 comprises a housing means 45 including, at the upper end, a top coupling 46 having a threaded bore 48. Threaded bore 48 is adapted for connection to the upper portion of tool string 12. The lower end of top coupling 46 is connected to a ported mandrel 50 at threaded connection 52. Ported mandrel 50 is also a part of housing means 45. A sealing means 54 provides sealing engagement between top coupling 46 and ported mandrel 50. An intermediate portion of ported mandrel 50 is connected to the upper end of another component of housing means 45, valve case 56. Relative rotation between ported mandrel 50 and valve case 56 is prevented by the interaction of lugs 58 on the ported mandrel with corresponding lugs 60 on the valve case. An annular flange 64 on ported mandrel 50 engages the lower end of lugs 64 of valve case 56, preventing relative longitudinal movement between the ported mandrel and valve case when top coupling 46 is connected to ported mandrel 50. A sealing means 66 provides sealing engagement between top coupling 46 and valve case 56. The lower end of ported mandrel 50 comprises a substantially cylindrical portion 68 having a closed lower end 70. Cylindrical portion 68 of ported mandrel 50 defines a plurality of substantially transverse ports 72 therethrough adjacent to closed end 70. It will be seen that ports 72 are in communication with central cavity 74 in ported mandrel 50 which is also in communication with the upper portion of tool string 12, specifically sample chamber 20. Cylindrical portion 68 of ported mandrel 50 has an outside diameter 76. A plurality of upper seals 78 are disposed in corresponding grooves in outside diameter 76 on one side of ports 72, and a plurality of lower seals 80 are disposed in corresponding grooves in outside diameter 76 on an opposite side of ports 72. Thus, a first and second sealing means is provided on opposite sides of ports 72. Slidably engaged with outside diameter 76 on cylindrical portion 68 of ported mandrel 50 is a first bore 82 of a valve sleeve 84. Thus, a sliding valve means 85 is provided, of which valve sleeve 84 is a part. It will be seen that first bore 82 is sealingly engaged with seals 78 and 80. An annulus 86 is defined between valve sleeve 84 and the wall of valve case 56. A plurality of substantially transverse ports 88 are defined through valve sleeve 84. In the position shown in FIG. 2A, ports 88 are disposed above upper seals 78. This corresponds to a closed position of valve means 85. Below ported mandrel 50, a plurality of generally slotted transverse openings 90 are defined through valve sleeve 84. It will be seen that transverse openings 90 provide communication between annulus 86 and a longitudinally extending central opening 92 defined in tester valve 10. Referring now to FIG. 29, the lower end of valve sleeve 84 is attached to valve connector or collet 94 at threaded connection 96. Valve connector 94 forms a lower end of valve means 85 in the embodiment shown. The lower end of valve case 56 is connected to a circulating case 98, which thus forms another portion of housing means 45, at threaded connection 100. A sealing means 102 provides a seal between valve case 56 and circulating case 98. Circulating case 98 has a first bore 104 and a somewhat smaller second bore 106 therebelow. A third bore 108 is defined below second bore 106. Valve connector 94 has a plurality of downwardly extending collet fingers 110 thereon which are adapted for engagement with an annular collet groove or recess 112 in the upper portion of a circulating mandrel 114. In the embodiment shown, circulating mandrel 114 is the upper component of a bypass means or bypass valve means 116. A sealing means, such as wiper ring 118, is provided between circulating mandrel 114 and valve connector 94. An annulus 120 is defined between an upper portion of circulating mandrel 114 and circulating case 98. It will be seen by those skilled in the art that, because of longitudinal gaps between collet fingers 110, annulus 120 is in communication with annulus 86. A substantially transverse port 122 is defined through circulating mandrel 114, thus providing communication between annulus 120 and central opening 92. Referring now also to FIG. 2C, circulating mandrel 114 has an enlarged lower portion 124 which is in closely spaced relationship to third bore 108 in circulating case 98. Circulating case 98 has a substantially transverse case bypass port 126 therein, also referred to as a housing port 126, and a sealing means 128 is provided between circulating mandrel 114 and circulating case 98 at a longitudinal position above case bypass port 126. The radially outer surface of lower portion 124 of circulating mandrel 114 has a single indicator groove 130, a double indicator groove 132 and a triple indicator groove 134 therein which are visible through case bypass port 126 depending upon the position of circulating mandrel 114 with respect to circulating case 98. These grooves are used to check the position of circulating mandrel 114 during make-up of tester valve 10 and the testing thereof at the surface before it is installed in tool string 112. In the various positions, the grooves are aligned with, and visible through, housing port 126, as is illustrated for double indicator groove 132 in FIG. 2C. Lower portion 124 of circulating mandrel 114 is connected to a circulating valve sleeve 136 at threaded connection 138. Circulating valve sleeve 136 defines a plurality of substantially transverse circulating valve ports 140 therein which are in communication with central opening 92. Sealing means, such as seal ring 142 of above ports 140 and O-ring 144 below ports 140 sealingly engage third bore 108 in circulating case 98. Thus, it will be seen by those skilled in the art that, in the configuration shown in FIG. 2C, circulating valve ports 140 are sealingly isolated from case bypass ports 126. This corresponds to one closed position of bypass means 116. The lower end of circulating case 98 is attached to sealing nipple 146 at threaded connection 148. Sealing means 150 provides sealing engagement between circulating case 98 and sealing nipple 146. The lower end of sealing nipple 146 is connected to oil case 152 at threaded connection 154. Both sealing nipple 146 and oil case 152 will be seen to form part of housing means 45. Connected to the lower end of circulating valve sleeve 136 at threaded connection 154 is an operating mandrel 156. Operating mandrel 156 thus forms a portion of bypass valve means 116. It will be seen that an annulus 158 is defined between operating mandrel 156 and a portion of housing means 45. A plurality of operating mandrel ports 160 are defined through operating mandrel 156, thus providing communication between annulus 158 and central opening 92. Referring now to FIG. 2D, sealing nipple 146 has an enlarged lower end which is in closely spaced relationship to bore 162 in oil case 152 and outside diameter 164 of operating mandrel 156. An outer sealing means 166 provides sealing engagement between sealing nipple 146 and bore 162 of oil case 152, and an inner sealing means provides sealing communication between sealing nipple 146 and outside diameter 164 of operating mandrel 156. It will be seen tha't an annular volume 170 is defined between outside diameter 164 of operating mandrel 156 and bore 162 of oil case 152. As will be discussed in more detail herein, annular volume 170 is filled with oil and thus forms an upper portion of an oil chamber 172. Slidably disposed in annular volume 170 is an upper floating piston 174. Outer and inner piston sealing means 176 and 178, respectively, provide sealing engagement between floating piston 174 and bore 162 of oil case 152 and outside diameter 164 of operating mandrel 156. A substantially transverse oil case port 180 is defined in oil case 152 at a position adjacent to the upper end of upper floating piston 174 and above outer and inner piston sealing means 176 and 178. Thus, well annulus pressure is in communication with the upper side of upper floating piston 174. An oil filler port 182 is provided in oil case 152 in communication with annular volume 170 so that oil chamber 172 may be filled. Oil filler port 182 is closed by a pipe plug or other similar means. The lower end of oil case 152 is connected to an operating case 184 at threaded connection 186. A sealing means 188 provides a seal between oil case 152 and operating case 184. Referring now to FIGS. 2D and 2E, the lower end of operating mandrel 156 is connected to ratchet 190 at threaded connection 192 with sealing engagement therebetween provided by sealing means 194. Ratchet 190 thus forms a portion of bypass valve means 116. As best seen in FIG. 2D, a variably sized annular volume 196 is defined between the inner surfaces of operating case 140 and the outer surfaces of operating mandrel 156 and ratchet 190. This annulus 196 is in communication with annular volume 170 and thus also forms a portion of oil chamber 172. As shown in FIG. 2E, operating case 184 has a first bore 198 with a somewhat larger second bore 200 therebelow. Ratchet 190 has an outside diameter 202 spaced inwardly from first bore 198 in operating case 184 such that an annular volume 204 is defined therebetween. It will be seen that annular volume 204 is another portion of oil chamber 172. An operating case port 205 is provided for filling oil chamber 172. Referring also to FIG. 3, outside diameter 202 of ratchet 190 defines a recessed "J-slot" ratchet pattern 206 therein. Engaging J-slot 206 is a ball bearing 208 carried by an operating valve 210 of an operating valve assembly or means 212. As will be discussed in more detail herein, the relative position of ball bearing 208 and J-slot 206 determines the positions of bypass valve means 116 and valve means 85. An outer sealing means 216 provides sealing engagement between a lower portion of operating valve assembly 212 and second bore 200 of operating case 184, and an inner sealing means 218 provides sealing engagement between the lower portion of operating valve assembly 212 and a second outside diameter 220 of ratchet 190. The lower end of operating case 184 is attached to power nipple 226, another component of housing means 45, at threaded connection 228. An outer sealing means provides sealing engagement between power nipple 226 and operating case 184, and an inner sealing means 232 provides sealing engagement between first bore 234 of power nipple 226 and second outside diameter 220 of ratchet 190. Referring also to FIG. 2F, power nipple 226 defines a substantially longitudinal passageway or bore 236 therethrough, and it will be seen by those skilled in the art that longitudinal passageway 236 forms still another portion of oil chamber 172. A substantially transverse power nipple port 238 is defined in power nipple 226 to facilitate filling of oil chamber 172 with oil. Below first bore 234 in power nipple 226 are a second bore 240 and a third bore 242 which is slightly larger than second bore 240. The lower end of power nipple 226 is connected to gas case 244 at threaded connection 246. Gas case 244 is another component of housing means 45, and an outer sealing means 248 provides sealing engagement between power nipple 226 and gas case 244. The upper end of a gas mandrel 250 is disposed in third bore 242 of power nipple 226. An inner sealing means 252 provides sealing engagement between power nipple 226 and gas mandrel 250. Gas mandrel 250 extends downwardly through gas case 240 such that an annular gas chamber 254, is defined between outside diameter 256 on gas mandrel 250 and bore 258 in gas case 244. A lower floating piston 260 is slidably disposed in gas chamber 254. An outer sealing means 262 provides sealing engagement between lower floating piston 260 and bore 258 of gas case 244, and an inner sealing means 264 provides sealing engagement between floating piston 260 and outside diameter 256 of gas mandrel 250. Annular volume 254 is preferably filled with a compressible, substantially inert gas such as nitrogen. It will thus be seen by those skilled in the art that the lower end of lower floating piston 260 is in contact with the gas, and the upper end of floating piston 260 is in contact with oil in oil chamber 172. Referring now to FIG. 2G, the lower end of gas case 244 is attached to filler valve body 266, another component of housing means 45, at threaded connection 268. Sealing means 270 provides sealing engagement between gas case 244 and filler valve body 266. The lower end of gas mandrel 250 is also connected to filler valve body 266 at inner threaded connection 272, and another sealing means 274 provides sealing engagement between gas mandrel 250 and filler valve body 266. Filler valve body 266 defines a substantially longitudinally extending hole 274 therein which is in communication with gas chamber 254. Filler valve body 266 also defines a port 276 extending substantially transversely with respect to hole 274 and in communication therewith. A filler valve (not shown) of a kind known in the art is positioned in port 276 to allow filling of hole 274 and annular volume 254 with the desired gas. The lower end of filler valve body 266 is attached to lower adapter 278 at threaded connection 280. Lower adapter 278 is the lowermost component of housing means 45 in the embodiment shown in the drawings, and a sealing means 282 provides sealing engagement between filler valve body 266 and lower adapter 278. The lower end of lower adapter 278 has an external thread 284 and a sealing means 286 adapted for engagement with a lower portion of tool string 12. Tool string 12 is lowered into well bore 14 to position at which perforating guns 34 are approximately aligned with formation 42 to be tested. Packer 28 is placed into sealing engagement with well bore 14 by inflation or other means in a manner known in the art so that an upper well annulus portion 288 is defined above packer 28, and a lower well annulus portion 290 is defined below packer 28. When tool string 12 is positioned in well bore 14 and packer 28 inflated, the configuration of tester valve 10 is such that valve means 85 is in the closed position shown in FIGS. 2A-2G. Also, bypass valve means 116 is generally in the closed position shown in FIGS. 2A-2G, although tester valve 10 could be run into well bore 14 with bypass valve means 116 in the open position. Referring now to FIGS. 3 and 4, with both valve means 85 and bypass valve means 116 closed, tester valve 10 is said to be in a "blank" position as indicated by numeral 5. FIG. 4 is a schematic showing the various positions of tester valve 10, and the numerals in FIG. 4 correspond to the positions on J-slot 206 shown in FIG. 3. FIG. 4 has no significance as to rotation of the tool, however. By applying pressure, as by a surface pump, to upper well annulus 288 above packer 28, pressure is thus applied above upper floating piston 174 through oil case port 180. The well annulus pressure thus forces floating piston 174 downwardly, and because the oil filling oil chamber 172 is substantially incompressible, it will be seen that operating valve assembly 212 is thus forced downwardly. This in turn causes lower floating piston 260 to be moved downwardly, thereby compressing the gas in gas chamber 254. As operating valve assembly 212 is moved downwardly toward its lowermost position as shown in FIG. 2E, ball bearing 208 moves downwardly through J-slot 206 until ball bearing 208 is at a position approximately midway between positions 6 and 7 on the J-slot. Pressure in well annulus 288 is then relieved, and the gas pressure in gas chamber 254 acts upwardly on lower floating piston 260 which in turn forces upwardly upper floating piston 174 and operating valve assembly 212. During this movement, ball bearing 208 engages surface 292 at position 6 in J-slot 206 and forces bypass valve means 116 upwardly until it is in a bypass or open position in which ports 140 in circulating valve sleeve 136 are substantially aligned with case bypass port 126 in circulating case 98 of housing means 45. It will be seen by those skilled in the art that as bypass means 116 is moved to this bypass position, collet fingers 110 on valve sleeve 84 will be forced outwardly in first bore 104 of circulating case 98 as circulating mandrel 114 of bypass valve means 116 moves upwardly, so that the collet fingers are disengaged from collet recess 112. In other words, when bypass valve means 116 is in the open position, collet recess 112 is above the lower end of collet fingers 110. It will be seen that at all times the pressure acting on the bypass valve means above and below ports 140 is equalized by means of ports 122 and 160. When bypass valve means 116 is in the open position, well annulus 288 is again repressurized. When this occurs, operating valve assembly 212 is again actuated downwardly in the same manner as previously described. In this instance, ball bearing 208 moves downwardly from position 6 in J-slot 206 to position 7. Operating valve assembly 212 reaches its lowermost point without engaging the J-slot at position 7 so that no movement of bypass valve means 116 occurs during this pressurization. When bypass valve means 116 is in the open position, and annulus 288 pressurized, it will be seen that well annulus pressure is thus communicated to central opening 92 of testing tool 10. Central opening 92 is in communication with lower portions of testing string 12, and this pressurization is used to actuate firing means 36. As previously indicated, firing means 36 is preferably a time delayed firing means. That is, once actuated by the well annulus pressure, the firing means will not trigger perforating guns 34 for a preset period of time, such as five to ten minutes. During this time delay, the operator at the surface relieves the pressure in well annulus 288, thus allowing operating valve assembly 212 to again be forced upwardly by the biasing means provided by the gas in gas chamber 254, at which point ball bearing 208 will be located in J-slot 206 corresponding to position 8 thereof. At this point, well annulus 288 is again pressurized. Actuating valve assembly 212 is forced downwardly such that ball bearing 208 engages surface 294 at position 8 in J-slot 206, thus forcing bypass valve means 116 downwardly so that it is again in a closed position. At this point, triple indicator groove 134 on circulating mandrel 114 is approximately aligned with case bypass port 126. Pressure in well annulus 288 may then again be raised and relieved which actuates actuating valve assembly 212, moving bypass valve means 116 downwardly to the position shown in FIGS. 2A-2G in which double indicator groove 132 is aligned with case bypass port 126. At this point, the lugs on the lower end of collet fingers 110 engage collet recess 112 on circulating mandrel 114. This cycling does not really functionally change the positions of bypass means 116 or valve means 85, but does allow pressurization of the well annulus to carry out other functions on other tool string components if needed. The closing of bypass valve means 116 is carried out prior to the firing of perforating guns 34. Once guns 34 fire, well casing 44 is perforated so that fluid from well formation 42 flows into lower well annulus 290. The fluid in well annulus 290 flows into tool string 12 through check valve 32 in a manner known in the art and is thus in communication with central opening 92 in tester valve 10. Debris from the perforating operation either falls to the bottom of well bore 14 or, once entering testing string 12 through check valve 32, will fall downwardly into blank guns 38. Also, the size of blank guns 38 determines the first blow period after fluid first enters back check valve 32. The instrumentation in gauge carrier 40 measures the change in pressure and temperature versus time, which is read out at the surface in a manner known in the art. Before or after perforating guns 34 fire, the pressure in well annulus 288 is again relieved so that actuating valve assembly 212 moves upwardly in J-slot 206 so that ball bearing 208 is approximately aligned at position 2 in the J-slot. It will be seen, of course, that tester valve 10 is still in a blank position with both valve means 85 and bypass valve means 116 closed. To flow a sample of fluid into sample chamber 20 above tester valve 10, pressure in well annulus 288 is again increased which forces operating valve assembly 212 downwardly. The engagement of ball bearing 208 against surface 296 forces bypass means 116 downwardly from the closed position shown in FIGS. 2A-2G, but bypass means 116 remains closed. At this point, single indicator groove 130 is approximately aligned with case bypass port 126. Because of the engagement of collet fingers 110 with collet recess 112, it will be seen that this further downward movement of bypass valve means 116 pulls valve means 85 downwardly as well. When actuating valve assembly 212 reaches its lowermost position, valve means 85 will be in an open position wherein port 88 in valve sleeve 84 will be substantially aligned with ports 72 in cylindrical portion 68 of ported mandrel 50. Thus, central opening 92 in tester valve 16 will be placed in communication with central cavity 74 above ports 72. A sample of fluid may then flow upwardly from well annulus 290 through check valve 32, through tester valve 10 and into sample chamber 20. Gauge carrier 22 is then used to measure the changes in pressure and temperature versus time as sample chamber 20 is filled. When pressure is relieved in well annulus 288, ball bearing 208 on operating valve assembly 212 will be moved to approximately position 2½ in J-slot 206. The well annulus can be again pressurized so that operating valve assembly moves downwardly where ball bearing 208 is at position 3 in J-slot 206. When this pressure is relieved, ball bearing 208 will be moved to approximately position 3½ in J-slot 206. As will be seen by those skilled in the art, this has no effect on the position of bypass valve means 116 or valve means 85. This allows the use of well annulus pressure to be used to actuate other devices in testing string 12, if any, without closing valve means 85. However, if well annulus 288 is pressurized once again, it will be seen that ball bearing 208 moves downwardly to approximately position 4 in J-slot 206, and when the pressure is relieved, the ball bearing on operating valve assembly 212 engages surface 298 at position 4, thus forcing bypass valve means 116 upwardly and valve means 85 upwardly bypass valve means such that tester valve 10 is again in the blank position shown in FIGS. 2A-2G. At this point, it will be seen by those skilled in the art that the cycling system can be restarted as desired. It will be seen, therefore, that the above packer perforate, test and sample tool of the present invention is well adapted to carry out the ends and advantages mentioned as well as those inherent therein. While a presently preferred embodiment of the apparatus has been shown for the purposes of this disclosure, numerous changes in the arrangement and construction of parts may be made by those skilled in the art.

Claims: A downhole tool for use with a tool string (12) in a well bore (14), comprising: guns (34) for perforating a well formation (42) in said well bore; firing means for firing said guns; a packer (28) disposed above said guns and said firing means for isolating said formation from an upper well annulus position (288) above the said packer; and a valve comprising housing means (45) for connecting to said tool string, said housing means defining a substantially longitudinally extending central opening (92) therethrough; bypass means (116) on said housing means for providing communication between said central opening and a well annulus portion (288) above said packer, whereby annulus pressure can be communicated to a tool string portion below said packer in use of the valve, said bypass means having selectable open and closed positions; and valve means (85) disposed above said bypass means in said housing means (45) for providing communication between said central opening and a portion of said tool string above said housing means, characterised in that the tool further comprises a sample chamber (20) disposed above the packer (28) and that the said valve means comprises an axially sliding valve (84) selectively disposable between open and closed positions, the valve being in communication with the sampling chamber, and that the sliding valve means, when in open position, connects the well formation to the sampling chamber for the chamber to be filled with a sample of fluid, and that actuating means (174,190,212) are provided for selectively opening and closing said bypass means and said valve means alternately and closing both together. A tool according to claim 1, further comprising biasing means (254) for biasing said actuating means upwardly within said housing means. A tool according to claim 2, wherein said biasing means comprises a gas filled chamber (254) providing an upwardly acting pressure on said actuating means. A tool according to any of claims 1 to 3, wherein said sliding valve means comprises: a mandrel (50) disposed in said housing means and defining a mandrel port (72) therein in communication with said portion of said tool string above said housing means; and a valve sleeve (84) slidably disposed on said mandrel and defining a valve port (88) therein, said valve port being substantially aligned with said mandrel port when said valve means is in said open position. A tool according to claim 4, wherein said bypass means comprises: a housing port (126) in the housing means (45) and a bypass valve (116) slidably disposed in said housing means and defining a circulating valve port (140) therein, said circulating valve port being substantially aligned with said housing port when said bypass means is in said open position. A tool according to claim 5, further comprising: a ratchet (190) on said sliding bypass valve; and an operating valve assembly (212) engaging said ratchet for longitudinally sliding said bypass valve in response to well annulus pressure. A tool according to claim 5, further comprising collet means (110) for releasably connecting said valve sleeve with said bypass valve. A tool according to any of claims 1 to 7, further comprising indicator means (130,132,134) for indicating a position of said bypass means with respect to said housing means. A valve (10) for use in the downhole tool of claim 1, the said valve comprising: housing means (45) for connecting to said tool string, said housing means defining a substantially longitudinally extending central opening (92) therethrough; bypass means (116) on said housing means for providing communication between said central opening and a well annulus portion (288) above said packer, whereby annulus pressure can be communicated to a tool string portion below said packer in use of the valve, said bypass means having selectable open and closed positions; and valve means (85) disposed above said bypass means in said housing means (45) for providing communication between said central opening and a portion of said tool string above said housing means, characterised in that the said valve means comprises an axially sliding valve (84) selectively displaceable between open and closed positions and actuating means (174,190,212) for selectively opening and closing said bypass means and said valve means alternately and closing both together.

Inventors: MCMAHAN MICHAEL E, MCMAHAN, MICHAEL E.
Applicants: HALLIBURTON CO, HALLIBURTON COMPANY
Application year: 1989
Main classification: E21B34
IPC codes: E21B43, E21B23, E21B34, E21B49