US 3499485 A
Abstract available in
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Description (OCR text may contain errors)
C. L. PHILLIPS WELL TOOL COMBINATION AND ADAPTER March 10, 1970 9 Sheets-Sheet 1,
Filed Nov. 4, 1968 CLA YTON L. PHILLIPS 69k -JNVENTOR 169a BY W A TTORNEY March 10, 1970 c. L. PHILLIPS 3,499,485
WELL TOOL COMBINATION AND ADAPTER Filed Nov. 4, 1968 9 Sheets-Sheet 2 19/200 //92 24: I73 I76. I
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WELL TOOL COMBINATION AND ADAPTER Filed Nov. 4, 1968 v 9 Sheets-Sheet 5 T aez T 9 9 see z4l 368 T sec, 367 x I 362 20 WATER TEST TUB/N6 a Bow I I! 6A5 TEST 1 AcRoss a TUB/N6 JOINT :H Li:
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ATTORNE Y MarchlO, 1970 c. PHILLIPS 3,499,485
WELL TOOL comsmmxon AND ADAPTER Filed Nov. 4, 1968 9 Sheets-Sheet e C LA To/v L PHILLIPS I N VENTOR v Z L 51M 24 I 23 5 ATTORNEY March 10, 1970 Filed Nov. 4,
c. 1.. PHILLIPS 3,499,485
WELL TOOL COMB IN ATION AND ADAPTER 9 Sheets-Sheet ATTORNEY United States Patent 3,499,485 WELL TOOL COMBlNATION AND ADAPTER Clayton L. Phillips, Rte. 4, Box 793B, Houston, Tex. 77040 Continuation-impart of application Ser. No. 620,043,
Mar. 2, 1967. This application Nov. 4, 1968, Ser.
Int. Cl. E21b 33/03, 43/00 U.S. Cl. 166-67 9 Claims ABSTRACT OF THE DISCLOSURE The invention includes a well tool for testing well tubing for leakage, section by section, as a tubing string is built up in a well bore, one channel supplying upper, central and lower packer setting liquid to isolate an upper annular space for liquid testing for leakage, and a lower annular space for gas testing for leakage across tubing joint; the tool also providing another channel for conveying test liquid to the upper annular space, and still another channel for conveying test gas to the lower annular space.
The invention relates primarily to apparatus and methods for isolating test space upwardly for liquid test for well tubing leakage and downwardly for gas test for well tubing leakage between tubing joints; this application being a continuation-in-part application of application Ser. No. 620,043, filed Mar. 2, 1967, for Well Tool Combination and Apparatus and Methods Associated Therewith.
The part of the invention that is added as new by this application has as a primary and most important object the provision of a tubing testing tool which supplies fluid through three separate channels, respectively, to set packers to isolate upper and lower test spaces, to test the upper space with liquid for tubing leakage, and to test the lower space with gas for tubing joint leakage.
For instance, for a special usage, it is a primary and important object of this invention to provide a well tool combination and associated apparatus of this class which is adapted to pressurize perforated well bore casing at the determined locations of perforation, as to force a fluid plastic through the perforations and into the formation outwardly of the perforated casing, until the perforations are stopped by the plastic, as may be indicated by a rise in the pressure indicated by the gauge connected into the high pressure fluid line at the top of the well.
Also, as another object of the invention, a well tool combination and associated apparatus is provided which may be operated successively to dispose the lower tool packers to straddle pipe or tubing joints of easing or tubing to be tested by use of a highly pressurized, inert gas as the test fluid, for more quickly and accurately discernable test indications, while water may be used as the low pressure, packer setting fluid.
Also, it is still another object of the invention to provide a well tool combination and associated apparatus of this class in which the adapter is connected to the tool therebelow by an outer tubular member of substantially the same diameter as the adapter and as the barrel of the tool therebelow which extends from below the upper packer and test port to a point above the lower packer, the packer setting pressure fluid filling the outer tubular member around the inner tubular member carrying the test pressure fluid, the barrel also carrying the lower packer setting pressure fluid.
It is also a further object of the invention to provide a console employable with a tool combination of this class, which includes a tool handling cable winch thereon, and means to pressurize an inert gas dispenser pressure vessel for delivery of test gas into the tool combination as the high pressure fluid.
It is also an additional object of the invention to provide two consoles on the drilling rig floor for use with a combination of this class, each console carrying a tool handling cable winch thereon, one console including means to pressurize an inert gas pressure vessel dispenser for delivering test gas into the tool combination for deep high pressure testing, and the other using conventionally delivered water for testing, as when a tubing string is being built up as lowered into the well bore.
Additionally, it is obviously a further object of this invention to provide a well tool combination and associated apparatus of this class, which is adapted to test a tubular string as already disposed in a well bore.
Furthermore, it is apparent that it can be an object of the invention to test pipe, stand by stand, as it is assembled onto a string of pipe being put together as lowered into a well bore, this being especially a desirable object when the stands of pipe are exceptionally long.
Also, it is an important and special object of the invention in that the consoles may be series connected as to the water connections for setting and relieving the packers of the tool in the well bore.
As a primary and most important object, the part of the invention added by this application sets out to provide a testing tool adapted to use a pressurized gas for testing the joints between tubing sections while using a liquid, as water, for setting the packers straddling the respective tubing section joints, and also for setting the packers which isolate barrel portion of the tubing just above the tubing joints, water through a separate channel also being used for testing the barrel portions.
The part of the invention that is new has as an additional object the provision of a tool of the three-channel, water testing for leakage, gas testing for joint leakage, and water for packer setting class, which additionally provides a tool head with an upstanding means adapted for entrapment by a cavity provided overshot, also included by the invention.
Also, the part of the invention that is new has the object of providing a tool that may be assembled quickly to any predetermined length between tool head and gas test mandrel, by extending an inner central gas tubing by plug-in sections while extending an outer water barrel by thread engaged sections.
Additionally, the part of the invention that is new has the object of providing a tool having packer assemblies with the expandible element comprised of a single resilient packer at a station, whereby a minimum tested tubing space is occupied by packer contact at the instant of testmg.
Furthermore, the part of the invention that is new provides for a number of improved method steps in tubing testing for leakage, both as to steps and methods for isolating test spaces, and as to steps and methods of promptly and accurately applying the tests.
Other and further objects will be apparent when the specification herein is considered in connection with the drawings, in which:
FIG. 1 is an elevational view, partially diagrammatic, of a drilling rig platform and derrick showing apparatus operative in aprt of the herein invention;
FIG. 2 is a flow diagram, part in sectional elevation; partially diagrammatical; and part in plan view as taken along line 22 of FIG. 1;
FIG. 3 is an elevational view of a cross-over adapter, tubing string and upper part of a testing tool as employed as part of one embodiment of the invention;
FIG. 3A is an elevational view of the lower part of the aforesaid testing tool;
FIG. 4A is a large scale, sectional elevational view of the cross-over adapter, shown to smaller scale in FIGS. 1 and 3;
FIG. 4B is a large scale, sectional elevational view of the upper part of the testing tool shown to smaller scale in FIG. 3;
FIG. 4C is a large scale, sectional elevational view of the upper central part of the testing tool shown to smaller scale in FIGS. 3 and 3A;
FIG. 4D is a large scale, sectional elevational view of the lower central part of the testing tool shown to smaller scale in FIG. 3A;
FIG. 4B is a medium scale, sectional elevational view of the lower part of the testing tool shown to smaller scale in FIG. 3A;
FIG. 4F is a medium scale, sectional elevational view of another form of the upper part of a testing tool, as shown to larger scale in FIG. 4B, associated apparatus also being shown as employed with the testing tool when used to test stands of pipe as installed on a pipe string as it is made up as lowered into a well bore;
FIG. 5 is a transverse bottom view, taken along line 5-5 of FIG. 4A;
FIG. 6 is an isometric top, rear and right side view of the console shown to smaller scale on the right side of the rig floor in FIG. 1;
FIG. 7 is a sectional elevational view of a modification of the cross-over adapter shown to smaller scale in FIGS. 1, 2 and 3;
FIG. 8 is a small scale elevational view of another embodiment of the tool shown in FIGS. 3 and 3A;
FIG. 9 is a plan view taken along line 9-9 of FIG. 8, showing detail of the head of the tool;
FIG. 10 is an enlarged, fragmentary, sectional elevational view of the upper part of the testing tool as taken along line 10-10 of FIG. 9;
FIGS. 11, 11A and 11B are transverse sectional plan views taken respectively along lines 11-11, 11A11A and 11B-11B of FIG. 10;
FIG. 12 is an enlarged, fragmentary, sectional elevational view of the next to uppermost part of the testing tool shown to small scale in FIG. 8;
FIG. 12A is a small scale elevational view of an alternative arrangement of the lower portion of the tool shown to small scale in FIG. 8;
FIG. 12B is an enlarged, fragmentary, sectional elevational view of the upper part of the alternative lower tool portion arrangement shown to small scale in FIG. 12A;
FIG. 120 is an enlarged, fragmentary sectional elevational view of a portion of the elevational view shown to smaller scale in FIG. 12A, showing adapter socket and spear extending downwardly therefrom;
FIG. 12D is an enlarged, transverse sectional plan view, taken along line 12D12D of FIG. 12B;
FIG. 12B is an enlarged, transverse sectional bottom view, taken along line 12E12E of FIG. 12B;
FIG. 13 is an enlarged, fragmentary, sectional elevational view of a regularly employed central part of the testing tool immediately below the part shown in FIG. 12;
FIG. 14 is an enlarged, fragmentary, sectional elevational view of the lower part of the testing tool immediately below the part shown in FIG. 13;
FIG. 15 is an enlarged, fragmentary, sectional elevational view of the next to lowermost part of the testing tool immediately below the part shown in FIG. 14;
FIG. 16 is an enlarged, fragmentary, sectional elevational view of the lowermost part of the testing tool shown in FIG. 8;
FIG. 17 is a modification of packer construction and packer setting piston action from the construction and action shown in FIGS. 13 and 15;
FIG. 18 is an enlarged, fragmentary, sectional elevational view of tool head and novel, wire line suspended overshot engageable with, and disengageable therefrom;
FIG. 19 is an enlarged, fragmentary, elevational view, part in section, of the lower, tool head engaging end of the overshot shown in FIG. 18; and
FIG. 20 is a transverse, sectional .plan view, taken along line 2(l20 of FIG. 19.
Referring in detail to the drawings in which like reference numerals are applied to like elements in the various views, a conventional drilling rig 10 is shown in FIG. 1 having a platform 11 above the ground level 12, and a derrick 13 thereabove, with a crown block 14 mounted immediately below the top of the derrick 13, and a travelling block 15 suspended below the crown block 14 to be raised and lowered by rig cables 16.
A tubing string 17 is shown in FIG. 1 supported by conventional drilling rig slips 18 in a rotary table 19 at substantially platform level. The tubing string 17 is shown as having a conventional nipple 23 as the uppermost element thereof, with the head 22 of a cross-over adapter 21 being shown above the tubing string uppermost nipple 23. The operation of the adapter 21 in combination with the other parts comprising the combination tool 20 will be gone into in detail in further paragraphs hereinbelow. On the other hand, as background, it is proper at this point to set forth the apparatus and steps employed in making up and testing the tubing string 17 above which is shown the cross-over adapter 21, as aforesaid.
The tubing string 17 is composed of stands of pipe or tubing, a stand being comprised of one, two or three, or even more adjoined sections. The stands awaiting assembly, not shown in FIG. 1, are stacked to stand up from the rig floor to lean outwardly at the top as supported by the upper part of the derrick 13. The stands are lifted by the drilling rig elevators 24 which are suspended from the travelling block 15 and the tubing string 17 is successively increased in length, stand by stand, by threading the lower end of the lowermost section of a stand to be added, into the nipple or uppermost member 23 of the then uppermost stand 114 of the tubing string 17.
When a stand is added and tested, the weight of the tubing string 17 is then supported by the travelling block 15, so that the slips 18, shown in FIG. 1, which have been supportingly engaged in the stand just above the level of the derrick floor 11, and below the uppermost stand under test, may be retracted. Then the tubing string 17, as engaged by the elevators 24, just below the top nipple 23, may be lowered by the travelling block 15 to position the newly added and tested stand of tubing just above the platform 11, and the slips 18 may be rearranged, to support the tubing string 17 When a tubing string 17 is ready to be lowered into a well bore, a truck 26, as shown in FIG. 1, together with a first and second service operator, has arrived at the location of the drilling rig 10 and the tool parts to be used have been taken from the truck 26 and assembled by the first service operator. In the meantime the drilling rig crew lends the use of the travelling block 15 to the second service operator, who connects the lift chain 27 of a console 28a to be engaged by appendages from the travelling block 15, and then the travelling block 15 is actuated by the rig crew to lift the console 28a and the conduits attached thereto, to the drilling rig floor 11, to be disposed as indicated in FIG. 1.
When the second service operator, now on the platform 11, has taken the free end of a wire line or winch cable 29 from a winch 30, which is mounted on the base 31 of the console 28a, and has passed this free end through a sheave block 32 and has then taken the sheave block 32 with the end of the cable 29 to the top of the derrick 13, the winch drum 30 being de-clutched to free wheeling to pay out the cable. The second service operator suspends the sheave block 32 from below the top of the derrick, and adjacent to the drilling rig crown block 14, and then brings back the free end of the cable or wire line 29 to the drilling rig floor or platform 11.
The truck bed 33 carries a water tank 34 just behind the truck cab 35, and behind the water tank 34 a skid 36 has mounted thereon apparatus including a pump 37 driven by a diesel engine 38. The pump 37 draw-s water from the tank 34 and delivers it under pressure through a conduit or hose 39 to the console 28a which controls delivery of water therefrom, selectively, into two flexible conduits or hose 40a, 40b. The second service operator now takes the free ends of hose 40a and 40b up inside the derrick 13 and suspends them over, and ties and tapes them to an upper derrick member 41 at predetermined distance from the free ends thereof, letting the free end portions extend downwardly to the drilling rig floor or platform 11, or slightly thereabove.
The tool that is employed in testing the successive stands of pipe which make up the tubing string 17, is not shown in FIG. 1, but such tool, designated by the tool assembly number 42 in FIG. 4F, comprises the upper head portion 43 shown in FIG. 4F, the lower head and upper packer portion 44 shown in FIG. 4C, the upper packer and central body portion 45 shown in FIG. 4D, and the lower packer and lower tool portion 46 shown in FIG. 4E.
The tool 42, comprised of the parts and portions hereinabove described is adapted to test the successive top stands of pipe for leakage as they are added. As a first step such tool 42 packs off or isolates an annular test space, not shown in any view, but which may be described as being within the tubing string 17 and around the tool 42, as described. The test space is the length of a stand of tubing, and extends upwardly from just below the uppermost nipple of that stand of tubing which has been tested to an elevation just below the uppermost nipple 23 of the aforesaid, now uppermost stand.
The free ends of the hose 40a, 40b are then passed through a guide sleeve 47 as shown in FIG. 4F. The hose 40a, 4012 have the respective free end fittings 48a, 48b thereof threadably connected over respective inlet connection fittings 49a, 4% which upstand from the upper surface of the tool head 43. The wire line or lift cable 29 may now be picked up and connected into a swivel 50, which comprises the upper part of a lift bar 51, the lower end of which may now be passed through the guide sleeve 47 and threaded into a threaded bore centrally disposed in the top surface of the tool head 43 of the tool assembly 42, indicated in FIG. 4F, and hereinabove described.
The tool head 43 is turned down, as shown in FIG. 4F to provide a rim flange 52 on which the guide sleeve 47 is positioned when the tool assembly 42 is ready for testing and with the guide sleeve 47 now seated in position on the rim flange 52, the second operator may lift the tool assembly 42, as by the wire line 29, which, as
aforesaid, has been passed over the sheave block 32 at the top of the derrick 13.
When the tool assembly 42 (elements 43, 44, 45 and 46 shown respectively in FIGS. 4F, 4C, 4D and 4E), has been lifted, to dispose the portion 46 at an elevation just over the top of the tubing string 17, the wire line 29 may be slackened off to lower the tool assembly 42 down through the open top of the tubing string 17 and downwardly into position for testing the next stand of pipe awaiting test. In this position the tool head 43, which comprises the upper most portion of the tool assembly 42, is supported upon the nipple 23 at the top of the tubing string 17, as shown in FIG. 4F, an underside groove 88 being provided in the tool head 43 into which the nipple 23 extends so that the base of the groove seats upon the top face of the nipple 23 comprising the uppermost element of the uppermost tubing stand 114.
It is of vital importance that the guide sleeve 47 is provided, so that when in lowered or operative position of the tool assembly 42, as well as in raised position there- 6 of, the hose a, 40b extend upwardly, and not transversely, from the tool head 43, thereby to insure that the connections of hose to tool head 43 may not be broken off, as by the exertion of shear in combination with pull thereon, as otherwise might occur.
Also, to protect the hose 40a, 401), the sleeve 47 must be of sufficient diameter and wall thickness to permit the hose 40a, 40b, to be draped arcuately over the top of the sleeve 47 when the tool assembly 42 is raised up out of testing position, whereby the hose 40a, 4%, are disposed so that the slack providing by lifting them drapes downwardly in loops between the top of the tool assembly 42 and the positions thereabove at which the hose 40a, 4012 are taped to the horizontally extending derrick member 41.
As shown in FIGS. 1 and 2, an air compressor 53 on the truck bed mounted skid 36 delivers compressed air through a discharge conduit 54 to a tank or reservoir 55, which is connected by a flexible hose or core conduit 56 passing centrally through a sheath 57 to a manifold 58 which has been taken with the console 28a to the drilling rig floor 11.
Also small scale, flexible compressed air conduits are indicated rising from apparatus shown in FIGS. 1 and 2, but without reference numerals being assigned thereto, and these extend through the sheath 57 outwardly of the compressed air supply conduit or core 56 within the sheath 57, to be controlled from the console 28a to operate, respectively, a gear box and clutch assembly 25 for selectively engaging and driving a hydraulic pump 59; the acceleration and de-celeration of the diesel engine 38; and the engaging and disengaging of a clutch 60, shown in FIG. 2, which respectively establishes and disestablishes driving connection between the shaft of the diesel engine 38 and the water pump 37.
In FIG. 4F the inlet fitting 49a into the tool head 43 establishes water communication with a vertical upper channel 62 of a packer setting water course 61 which delivers water to set an upper packer 63 (FIGS. 4C and 4D) and a lower packer 64 (FIG. 4E). The channel 62 (FIG. 4C), communicates with an annular groove 65 cut from a smooth bore 66 which has been drilled upwardly into the lower portion 44 of the tool head 43. A tool body 67 (FIG. 4D) includes an upper mandrel 68 which has successively an upper end 69 which fits into the smooth bore 66, an externally threaded portion 70 which is engaged into a threaded bore '71 provided in the lower end of the tool head portion 44, a shank 72 of substantial length (FIGS. 4C and 4D), and a larger diameter lower portion 73 providing an upwardly facing shoulder 88. The lower portion 73 of the upper mandrel 68 adjoins a largest or full diameter, central tool body portion 74.
The lower end of the tool body 67 comprises a lower mandrel 75 of substantially the outer diameter of the upper mandrel lower portion 73, and has external threads 76 thereon for threaded engagement with the internally threaded upper bore 77 of a tubular member or connection nipple 78 (FIGS, 4C and 4D), to be hereinbelow described. When the tool assembly 42 is fully made up, the annular groove 65 communicates with a radially inwardly extending passage 79 in the upper end '69 of the upper mandrel 68, and this passage 79 communicates in turn with a channel 80 forming part of the packer setting water course 62 and which extends vertically downwardly through the upper mandrel 68 and communicates at its lower end with a larger diameter bore 81, which has been drilled upwardly through the lower face 82 of the lower mandrel 76 and into the tool body portion 74. The upper end of the channel 80, above the passage 79, is closed by closure metal 80a. Also, the lower end of the channel 62 is closed by closure metal 62a.
A testing fluid passage 83 is also provided through the tool assembly 42, and such includes a vertically, axially extending flow passage 84 which extends downwardly from the inlet fitting 49b (FIG. 4F) through the upper tool head portion 43 and into the lower tool head portion 44 to communicate with a short bore 85 into the upper face of the upper mandrel upper end 69. Also, a vertically extending flow passage 86 has been drilled through the tool body 67, beginning at the top or upper face of the upper mandrel 68 and continuing downwardly into the tool body central portion 74. Such bore or flow passage 86 communicates with the short bore 85 at the top of the upper mandrel upper end 69, and at its lower end it communicates with a lateral, or horizontally, radially outwardly extending passage 87 to the exterior of the total body (see FIG. 4D). Closure metal 86a closes the flow passage 86 at its convergence with the bore 81.
Prior to assembly with the tool head 43, 44, an upper packet setting piston 90 is installed over the upper mandrel 68, the lower or cup portion 89 being slidable over the larger diameter, lower portion 73 of the upper mandrel so that the inner flange surface 91 of the cup substantially seats upon, or is just clear of the shoulder 73a, while the upper, or sleeve portion 92 of the piston 90 extends upwardly and snugly, slidable around the shank 72 of the upper mandrel 68. Fluid communication is established between the packer setting water course 61 and the underside of the piston cup 89 by providing a slot 103 in the outer surface of the larger diameter, mandrel lower portion 73, and providing a lateral, or radially extending bore 104 to connect the slot 103 with the packer setting water chanel 80 through the upper mandrel.
The upper packer 63, which the piston 90 sets, is comprised of a plurality of alternate metallic spacer rings 93 and extensible, resilient packer elements 94, as of rubber, are slid over the piston sleeve 92, the lowermost and uppermost members being spacer rings, with the uppermost spacer ring 93 abutting the lower face 95 of the lower head portion 44, as shown in FIG. 4C, while the top of the piston sleeve 92 is short of the face 95, by a distance Slightly greater than maximum piston travel, to set the packers 94.
As features of construction, an O-ring groove 96a is provided in the tool head portion 44 as cut from the smooth bore 66. Also two slightly, vertically spaced apart O-ring grooves 96b, 960 are provided in the tool head portion 44 below the annular groove 65 and above the threaded bore 71.
Thus provision is made against fluid leakage between the fluid channels 84 and 62, and against fluid leakage between the fluid channel 62 and between the tool head portion 44 and the mandrel 68. Also, an O-ring groove 96d is provided in the upper mandrel portion 73 to provide against fluid leakage from the fluid channel 62 between the mandrel 68 and piston cup 89. Additionally, an O-ring groove 96s is provided in the lower mandrel ortion 75 to provide against leakage between the tubular connection nipple 78 and the packer setting fluid within the tool body 74.
The lower packer and lower tool portion 46 shown in FIG. 4B includes a lower tool body 100 which comprises, successively, from top to bottom, an externally threaded upper end 97 for engagement with the internally threaded lower end of the tubular connection or spacer nipple 78, a lower tool body central portion 98, a reduced diameter, lower tool body mandrel portion 99, and a further reduced diameter shank 101, including lowermost an externally threaded, lower end portion 102.
Prior to assembly with an internally threaded spacer nut .105 and lock nut 118 comprising the finally installed element of the tool assembly 42, a lower packer setting piston 110 is slid upwardly over the lower tool body mandrel 106. This mandrel 106 comprises, successively downwardly, the mandrel portion 99, the shank 101, and the lower end 102. The cup portion 107 of the piston 110 is thus uppermost and slides upwardly over the mandrel portion 99, so that the inner flange surface 108 of the cup approximates seating upon the shoulder 109 of the mandrel portion 99. Then the lower or sleeve portion 111 of the piston 110 extends downwardly, and fits snugly, slidably around the shank 101 of the mandrel 106.
Correspondingly, as described in association with the upper piston 90, a slot 113 is provided in the outer surface of the mandrel portion 99, and a lateral or radially inwardly extending bore 117 is provided to connect the slot 113 with a bore 112 in the lower tool body 100, including the mandrel portion 99. Such bore 112 communicates with the interior 107 of the connection spacer or nipple 78 which in turn communicates with the packer setting water channel of the packer setting water course 61.
The lower packer 64, which is set by the piston 110, is comprised of alternate metallic spacer rings 93 and extensible, resilient packer elements 94, as of rubber, which are slid upwardly over the piston sleeve 111, the uppermost and lowermost elements being spacer ring 93. Assembly is completed when the spacer nut and the lock nut 118 are threaded upon the mandrel externally threaded lower end .102. In this assembly, as may be seen in FIG. 413, the piston 110, in unset or initial position, is supported by the lower packer 94 in manner that a distance slightly greater than maximum piston travel is left between thte bottom of the piston sleeve 111 and the spacer nut 105. An O-ring groove 115 is provided in the mandrel portion 99 above the fluid ports 113, 117 to prevent fluid escaping upwardly past the piston .10, and also an O-ring groove 116 is provided in the mandrel shank 101 below the shoulder 109.
The tool assembly 42, as disclosed in FIGS. 4F, 4C, 4D
and 4E, may be employed with the apparatus disclosed in FIGS. 1 and 2, as aforesaid, and fluid, as water, may be pumped from the pump 37, to pass, by way of the hose 39 and, as directed at the console 28a, to pass by way of the hose 40a, into the packer setting water course 61 of the tool assembly 42, and by Way of the included channel 62 in the tool head 43, 44 (FIGS. 4F, 4C) to pass into the groove 65, and thence by way of the mandrel port 79 into the mandrel flow channel 80. From the channel 80 (FIGS. 4C and 4D) fluid passes out the lateral port 104 of the upper mandrel 68, and upwardly through the slot 103 therein, to bear upwardly against the upper piston inner flange 91 and move the piston base upwardly to compress the packer rubbers or packer elements 94 longitudinally, as the lower face or shoulder 95 of the lower tool head portion 44 serves as an upward stop; Thus the packer elements or rubbers 94 of the upper packer 63, are moved outwardly to set position against the wall of the tubing string 17.
In the upper packer and central tool body assembly 45, (FIG. 4D), the flow channel 80 communicates with the interior 107 of the tubing section or tubular connectron member or nipple 78, which connects the upper and lower parts of the tool (FIGS. 4D and 4E). This element 78 is the member of the combination which is selectively of predetermined length to establish the desired packer to packer distance for various length requirements when the tool is usedto test well tubing stands for leakage.
The packer setting fluid from the nipple or tubular connection member 78 communicates with the bore 112 in the lower tool body 100, and from thence, via lateral port 113 and slot 117 in the lower tool body mandrel portion 99, the fluid may bear downwardly against the lower piston inner flange surface 108 and move the lower piston base downwardly to longitudinally compress the packer rubbers 94 of the lower packer 64. As longitudinally compressed, the packer elements 94 are urged radially outwardly into set position against the wall of the tubing string 17.
The tool assembly 42 (FIGS. 4F, 4C, 4D and 4E), tests the space between the set packers 63, 64, the test fluid, as supplied by apparatus shown in FIGS. 1 and 2, entering from the hose or conduit 40!) to pass down the test fluid water course 83 which includes the fluid channel 9 84 through the tool head 43, 44 (FIGS. 4F and 4C). Thence the test fluid enters the upper mandrel 84 by way of the top central bore 85 to pass down the fluid channel 86, in communication therewith, and out through the lateral port or passage 87 into the annular space defined inwardly by the tool 42 and outwardly by the Wall of the tubing string 17, with the respective set packer 63, 64, defining the upper and lower boundaries of the test space.
Since the pressure built up for testing (far above that required to set the packers), acts equally in all directions, and thus equally against the respective upper and lower packers 63, 64, the packers 63, 64 are not displaced upwardly or downwardly by the test pressures, but rather the tool 42 remains anchored in the tubing string 17. The test fluid and packer setting fluid employed may be a hydraulic fluid or an inert gas, as nitrogen, rather than air, thereby to avoid the danger of explosion which might otherwise arise should it be necessary to compress the air to such great pressure as to overheat it. Also one fluid at one pressure may be employed to set the packers and another fluid at a considerably higher pressure may be employed for testing.
The necessary operating apparatus, including the testing tools as hereinabove described, may all be carried by a single motor vehicle or floated small craft, respectively, and taken to the location of a drilling rig on a land based location, or on an overwater platform.
Description of the truck 26 and drilling rig 10, shown in FIGS. 1 and 2, with the necessary apparatus they carry, all in greater detail, follows: Immediately behind the cab 35 of the truck 26, the water tank or reservoir 34 is mounted. Immediately behind the water tank 34, on the skid 36, the remaining apparatus carried by the truck 26 is mounted. The apparatus includes the aforesaid water pump 37 carried forwardly and over the left forward corner of the skid 36. The pump 37 takes suction through a conduit 119 connected to an outlet conduit 120 from the Water reservoir 55, the conduit 119 being alternatively connectable to an outlet conduit 121 from an auxiliary water reservoir 122 located above the left side of the skid 33 to the rear of the pump 37 for use when an offshore drilling operation is served, and having a return water line or conduit, not shown, from an offshore drilling rig.
The suction conduit 119 connects into the pump suction intake 123 and the pump 37 discharges through a discharge outlet or conduit 124 which is extended to the console 28a on the rig floor 11, by the aforesaid conduit 39. The shaft 125 of the pump 37 has a sprocket 126 mounted on its forward, outer end, which is driven by a sprocket chain belt 127 from a pinion sprocket 128 on a line shaft 129.
The line shaft 129 extends longitudinally above the skid 36, substantially centrally thereof, and is supported for rotation by forward and rear pillow blocks 130, 131. v
The rear end of the line shaft 123 is clutch-connected by the aforesaid engine clutch 60 to the diesel engine drive shaft 132 which is aligned in rearward co-extension of the line shaft 129, and thus, the diesel engine 38 is disposed substantially centrally upon the skid 36, to the rear of the pump 37. The diesel engine 38 is supplied fuel from a fuel tank 133 on the left rear corner of the truck bed, which delivers fuel through a fuel line 134 to the con ventional diesel engine fuel feed pump, not shown.
Also, an electric storage battery 135 is mounted on the left side of the skid 36, and to the left of the forward end of the diesel engine 38, to supply starting current to a starting motor which rotates the diesel engine flywheel to start it, both motor and flywheel being conventional and not indicated separately from the diesel engine 38.
The aforesaid hydraulic pump 59, on the right rear corner of the truck bed, is driven by a shaft 137 which is connected to be driven by the diesel engine shaft 132 in forward alignment therewith. The shaft 136 transmits drive through the aforesaid gear box and clutch assembly 10 25 to the hydraulic pump shaft 137 at right angles thereto.
The air compressor 53 to the left and rear of the diesel engine 38, has a pulley on its shaft which is driven by a V-belt 138 from a pulley mounted on the shaft 136. The aforesaid compressor 53 discharges compressed air, through a discharge conduit 54 to an aforesaid compressed air reservoir or chamber 55. The chamber or reservoir 55 is best shown in FIGS. 1 and 2 as supported by a frame 139 which upstands from the skid 36, to extend above the engine 37 and along the longitudinal center line of the skid 36.
The aforesaid console 28a, when in transit, occupies the position shown in FIG. 2 on the left side of the skid 36 behind the battery and forward of the diesel fuel tank 133. Also a console 28b, shown installed on the right side of the drilling rig platform 11 in FIG. 1, occupies the position shown in FIG. 2 on the right central side of the skid 36 forward of a hydraulic fluid reservoir 158 and to the right of the diesel engine 38. Heretofore reference has been made only to the console 28a as such enters into the operation of the testing tool 42, (FIGS. 4F, 4C, 4D and 4E), whereas the console 28b and its operation with an inert gas, as nitrogen, employed as the test fluid will be described'hereinbelow.
A console is shown in isometric view in FIG. 6, which is designated 28a, 281) with all apparatus used on a console 28a which directs water or a similar liquid both to set the packers and test the tubing shown in full lines, and with the additional apparatus required to change such a console 28a to a console 28b, adapted to use an inert gas for testing, being shown in dotted lines.
Having described the tool 42, as adapted to test successively added stands of tubing, for leakage, the operation of the tool 42 with relation to the console 28a and related apparatus will be continued, FIGS. 1, 2 and 6, as follows: The console 28a comprises a base 31 from which upstand four legs, the rear legs 140a being shorter than the forward legs 14%, thus to mount a forwardly raised table top 141 thereon. A high capacity water gauge 142, which measures water pressures in excess of 20,000 psi, is mounted to the upper left of the table top 141 above the apex end of the base. Also, to the left and immediately below the high pressure water gauge 142, is mounted a compressed air gauge 143 of capacity to measure pneumatic pressures up to 115 p.s.i.
The liquid, as water, which is delivered by the pump 37 to operate the testing tool 42, is supplied through the discharge conduit or hose 39, which is extended from the truck 26 to the console 28a on the drilling rig platform 11, where the free end of such conduit 39 is connected to the lower end of rigid piping 144 on the console left rear leg 140a.
The piping 144 includes, successively, from lowermost to uppermost, a T 145 to which a recorder, not shown, may be connected to continuously record pressures, when such a record may be desired. Above the T 145 a check valve 146 is provided to protect against back pressures. Above the check valve 146 a T 147 is provided from which a flexible conduit 148 extends to the high pressure capacity water pressure gauge 142.
Above the T 147 the piping 144 makes a right angle turn, by means of an elbow 149, and extends horizontally to the right along the rear of the console top 141 and includes, from left to right: first, a T 150 into the lower leg of which a needle valve 151 is installed to the lower end of which is connected the aforesaid flexible conduit or hose 40a; second, a T 152 into the lower leg of which aneedle valve 153 is connected, with the lower end of the needle valve 153 having connected thereto the hereinabove described flexible hose or conduit 40b; and third, an elbow 154 is provided, from the lower leg of which the piping 144 turns downwardly and provides a needle valve 155 through which the water which sets the packers 1 1 may be released or bled off in order to deflate the packers 63 and 64, as will be hereinbelow described.
As aforesaid, the compressor 53 discharges through the conduit 54, and keeps the compressed air reservoir 55 full of air compressed to a pressure of approximately 115 psi. The aforesaid delivery conduit 56 from the compressed air reservoir 55 extends through the sheath 57 to the compressed air manifold 58 which is taken with the console 28a to the drilling rig floor or platform 11. From the manifold 58 three delivery conduits 156a, 1561; and 156C pass therefrom, as follows:
The conduit 156a connects into a three-way valve, beneath the table top 141, and not shown, but with a handle 157 movable to control compressed air direction to the gear box and clutch assembly 25 to engage drive with the hydraulic fluid pump 59 to deliver hydraulic fluid to the hydraulic motor 159 to drive the winch drum 30, selectively to pay out or take up cable 29.
The conduit 156!) connects into a spring balanced threeway valve 168 which actuates a compressed air cylinder 160 at the forward end of the diesel engine 38 to connect or disconnect the clutch 60 of the engine shaft 132 to the line shaft 129 which drives the water pump 37.
The conduit 156C connects to one side of a two-way valve, not shown, and is actuated by a foot pedal 161 to control the amount of compressed air admitted to the engine accelerator 162 to control the speed at which the engine 38 drives the water pump 37.
A bellcrank lever 163 has the upper part of its long arm extended through a slot on the table top 141 as a clutch handle, the lever being pivoted at 164 and its short arm being formed at 165 ordinarily, as shown in FIG. 6, to urge downwardly on the brake drum 166 of the winch 30. Thus, if the handle is drawn rearwardly the winch drum is released to wheel free.
As shown in FIGS. 1, 2 and 6, compressed air conduits 167a and 167b extend from the three-way valve having the handle 157 (through the same sheath 57 which houses the compressed air supply core 56 from the reservoir 55), back to the truck 26 and to the gear box and drive assembly 25. Thus the manipulation of the handle 157 at the console 28a connects drive to the hydraulic pump 59 so that it takes suction through the suction line 168 from the hydraulic fluid reservoir 158, and delivers the fluid into a hydraulic fluid channel 169a or 16%, as directed, thus to determine the direction of rotation of the hoist drive motor 159 for the winch drurn 30. The drive fluid for the motor, returns through that respective channel 169a or 169b, whichever is serving as the return conduit, and is directed from the gear box and drive assembly 25 through the return conduit 170 to the hydraulic fluid reservoir 158.
Also, as shown in FIGS. 1, 2 and 6, compressed air conduits 171a and 171b extend from the spring balanced, three-way valve 168 back through the aforesaid sheath 57 to the opposite sides of the compressed air cylinder, designated'160 in FIG. 2 (not outlined in detail), which selectively engages or disengages the engine clutch 60 to drive the water pump line shaft 129.
Furthermore, as shown in FIGS. 1, 2 and 6, a compressed air conduit 172 from the side of the foot pedal controlled valve, not shown, but opposite the compressed air supply conduit 1560, leads back through the sheath 57 to the engine accelerator 162, which is thus controlled by pressure exerted on the foot pedal 161 at the console 28:1.
Also, a T 224 is provided in the core conduit 56 as it emerges from the sheath 57, to connect into the compressed air manifold 58, and a conduit leads from the central leg of such T 224 to the compressed air gauge 143 on the console 28a, whereby the functioning of the compressed air supply may be observed at all times.
The operation of testing tubing can be carried out by a single truck over a long period of time as when tubing is tested in the process of making up tubing strings as suspended stand by stand into deep wells. While actual testing proceeds only a single operator is necessary and the other operator may be otherwise disposed to await his shift at testing. The engine 38 on the truck skid 33 having been started in conventional manner and with the tool 42 (FIGS. 4F, 4C, 4D and 4E), in testing position, as supported on the uppermost nipple 23 of the uppermost stand or tubing 114 the lever of the valve 168 is moved to up position to start the pump 37 and the operator controls the acceleration pedal 161 in depression and opens the packer setting valve 151 as the testing valve 153 and bleed valve are kept closed.
The pump 37 then draws water from the tank 34 and delivers it by way of the flexible conduits 39 and 40 to the packer setting water course 61 in the testing tool 42 to set the packets which isolate the test space between the set upper and lower packers 63, 64.
When the pressure indicated by the pressure gauge 142 informs the operator the upper and lower too-l packers are firmly set, he closes the valve 151 to lock the packers in set position and opens the valve 153 so that the pump delivers the hydraulic fluid as water through the hose 49b to the testing fluid course 83 in the tool to pass out into the annular test space, thus to place the uppermost stand of tubing 114, including its nipple joints 23, under testing pressure.
While the pump operates, the operator holding his foot sensitively on the pedal 161 thus senses the rate at which the pump 37 is pumping. As the fluid is delivered through the test channel 83, a higher pressure can be developed for testing than is necessary for setting the packers, and this pressure is reflected by the gauge 142, the fluid delivered by the hose 39 passing by way of the conduit 148 to set against the gauge 142. If the operator observes no falling off of the gauge he knows that there is no leakage in the stand length of tubing tested, and testing may proceed, and as a gauge reading stands steady the valve 153 may be closed.
Whether the gauge 142 indicates leakage by a falling off in its reading, or whether no leakage is indicated by the high reading holding constant, the operator gives the appropriate signal, pulls the lever of the valve 168 to down position to de-clutch the pump drive, and then releases such lever 168 to be spring returned to neutra position.
He then opens the bleed-off valve 155 and the packer setting valve 151 and the packers contract, as their rubbers tend to return to their normal position, and this forces out or bleeds off that amount of fluid that has gone to expand the packers, after which the bleed-off valve 155 may be closed. As the packers retract the water that has been used for testing falls down into the well bore and is thus expended as an operating fluid.
The operator now moves the handle 157 to up position to actuate the gear box and clutch assembly 25 to direct the fluid delivered by the hydraulic pump 59 to deliver into the conduit 169 thus to drive the motor 159 in direction to take up cable 29, whereby the cable 29 lifts the tool 42 up out of the stand of pipe 114 just tested, and clear of the operation of the travelling block 15 and the elevators 24 suspended therefrom, which normally engage as a safeguard right under the uppermost nipple 23, as for instance, to take up the support of the tubing string 17, in case of failure of the slips 18 to hold the tubing string.
The drilling rig crew now takes over operation, and if leakage has been indicated, the rig apparatus is used to remove the stand indicating leakage, and it is replaced by a new stand to be tested. Otherwise, when no leakage is indicated, the crew retracts the slips 18, while the elevators 24 below the travelling block 15 grasp the top of the tubing and the derrick thus supports the tubing string 17 from the crown block 14. Then the crew lowers the stand just tested and resets the slips 18 to support such stand with the top thereof slightly above the slips 18. Then the crew, using the travelling block 15 and elevators 13 24, adds anew stand of tubing to take position as an uppermost stand 114 awaiting test.
The operator now grasps the handle 157 (which has been spring returned to neutral position upon release to de-clutch the hydraulic pump 59 from engine drive), and upon the lever being pulled down and held in down position, hydraulic pump 59 aetuates the hoist motor 159 to drive the winch drum 30 in opposite direction to pay out cable 29 to lower the tool 24 into the next stand of tubing to be tested.
When the drum 30 is being driven in either direction, the operator does not have to hold his hand upon the upper end of the bellcrank lever 163, since this lever is balanced frictionally to hold settings thus continuously to maintain light braking contact with the winch brake drum 30. However, the operator does keep his foot sensitively on the foot pedal 161 to control the engine accelerator 162, both while the hosit 30 is operating, and while the water pump 37 is operatively engaged.
It may not be desirable to use a testing fluid which, when it is released, falls by gravity down into the well bore, where it may cause contamination. For instance, in many cases, it is not desirable to dilute or in any manner alter the constituency of a drilling mud or fluid used in drilling the well. Thus an inert gas, as nitrogen, may be used, thereby to obviate any contamination of the drilling fluids. In this case bottles or vessels 173 of nitrogen have been brought to the field on the service truck 26, as shown in FIG. 2, the truck 26 being otherwise laden with the apparatus hereinabove described.
The nitrogen bottles 173 have two-way valves at the tops thereof and above these valves they are series connected into a manifold 174 having a valve 175 at the outer end thereof from which extends a conduit 176 having two successively downwardly seating check valves 177a, 177b therein.
The upper end of the conduit 176 connects into the top of a pressure vessel or cylinder 178 as shown in FIG. 1 and diagrammatically in FIG. 2. The cylinder 178 has respective upper and lower hemispherical ends 179w and 17% to close the pressure vessel, and these ends carry respective handles 180a, 1801? by which the pressure ves sel 178 may be manipulated and mounted.
As shown in FIG. 1, this pressure vessel or cylinder 178 has been lifted from the truck 26 and taken up on the rig floor 11 and positioned on the derrick 13, as indicated. From the lower end of the lower closure 17% there extends a valve 181 which is connected by a flexible conduit 182 to the lower end of the test needle valve 153 on a second console 28b carried on the truck 26 when an inert gas is to be used for testing, at least in part. From the upper end of the cylinder 178 there extends a valve 183 which is connected by means of a conduit 184 to a T 185 at one end of piping 190, this piping 190 having been mounted on the right side of the console 28b, as shown in dotted lines in FIG. 6, thus to support the use of gas, as nitrogen, in testing. A gauge 186 is connected into the central leg of the T 185 to indicate the pressure of the nitrogen discharged from the cylinder 178 into the line 184.
Along the side of the console 28b, forwardly of the T 185, the piping 190 includes a valve 187 therein and farther forwardly it includes a T 188, and into the central leg of this T a nitrogen bleed-off valve 189 is connected. Then at the forward end of the piping 190 a valve 191 is provided into the forward end of which the flexible conduit or hose 40b is connected.
As the console 28b has been set up on the derrick floor 11, the conduit or hose 40b, along with the hose or conduit 40a extending from the needle valve 151, have been taken up into the derrick 13 to be suspended over and taped to an upper derrick member 143, corresponding in functions with the aforesaid horizontally extending derrick member 143. Also, as shown in FIG. 1, the free ends of the respective hose 40a and 4012 have been brought back down and extended through the guided sleeve 47 and connected to carry fluid to the respective packer setting and testing fluid courses or channels within the tool 42. Then the wire line or cable 29 has been connected into the swivel 50 at the top of the tool, and the tool 42 has been raised above the top of the tubing string 17, as supported by the slips 18 and with the elevators 24 engaged near the top as a safeguard, and then the tool 42 has been lowered down into the top of the tubing string 17 until the tool head 43 rests upon top of the nipple 23 of the uppermost stand of tubing 114.
In the meantime the cylinder, pressure vessel, or nitrogen reservoir 178 has been filled with nitrogen by opening banks of nitrogen bottles on the truck 26 to pass nitrogen into the manifold 174, and thence through the valve and by way of the conduit 176 and through the check valves 177a, 177b into the reservoir 178, and with the valve 183 open, up to the gauge 186 in the auxiliary console piping 190, the valve 187 in the piping and also the nitrogen bleed-01f valve 189 and the nitrogen delivery valve 191 being closed. Also the needle valves 151, 153, and 155 in the main console water piping 144 are closed at this point.
The operator now opens the needle valve 151 as the engine 38 is started, and operates the handle 157 to place the pump 37 in drive to pump water to pass through the hose 40a to set the tool packers 63, 64. Then he closes the valve 151 as he opens the valve 191 to let the nitrogen pass on through the hose 4% into the testing annulus about the tool 42, and at the same time opens the valve 153 so that the pump 37 now pumps water, by way of the hose 182, into the lower end of nitrogen reservoir 178 to pressurize the nitrogen as water rises in the reservoir to reduce the nitrogen space, as indicated in the cutaway section of the reservoir in FIGS. 1 and 2. As this takes place the nitrogen gauge 186 reflects the nitrogen pressure that is being developed and when the pressure attains the requisite figure to indicate that the stand of tubing 114 under test does not leak, or when the reflection of the gauge 186 falls off, to indicate leakage, as the case may be, in any event, the signal is given preceding the removal of the tool 42 from the tubing string 17 until a next stand may be added thereto.
In this case the operator moves the lever of the valve 168 to down position to de-clutch pump drive, and opens the water bleed-off valve 155 so that the water that has pressurized the nitrogen in the reservoir 17 8 may be released, and the sound of the beginning of nitrogen passage into the valve 181 indicates that this valve should be closed. By draining off the pressurizing water in this manner the nitrogen expands to fill the space evacuated by the water, and this reduces the amount of nitrogen in the test annulus and in the hose 40b leading up to the valve 187 which may now be closed. It should also be noted that the nitrogen pressurizing water is recoverable since a flexible conduit 192, shown in dotted lines in FIG. 2, can be installed to convey this fluid, by gravity, back to the water tank 34, or back to the auxiliary water tank 122 in case an offshore rig is being served from a motor vessel which carries the skid mounted apparatus thereon.
Then, with the valve 187 closed, and the valves 191 and 189 open, the test nitrogen remaining downstream of the valve 183 may be drained, at least in part, to the atmosphere. Then, with the valve 153 closed and the valve 151 open, the valve 155 may be opened to bleed off the water which has set the packers so that the tool may be removed, and the next stand 114 installed in the same manner as aforesaid.
The invention comprises essentially apparatus and method of testing tubing which permits all necessary apparatus to be carried on a single vehicle to a testing location. Also, the apparatus, which is skid mounted, can be transferred in whole to a small vessel and taken out to the location of an offshore drilling rig. In addition to the advantages of providing a compact portable assembly of equipment, the apparatus is designed for speed and operation as all of the levers and valve handles essential to carrying out testing are located on a console while the only two connecting elements which extend between the assembly of operating apparatus and the console comprise the water supply hose or flexible conduit and the sheath which has the compressed air connections therein which actuate the various apparatus, and which also has therein the flexible conduit core or compressed air supply line.
The invention also includes means and method for testing with an inert gas, as nitrogen, rather than water, where it may not be desirable to expend test water into the well bore, to contaminate or to change the constituency of products down in the well, such as the drilling mud.
Also, the invention permits the use of an inert gas in testing, and additionally permits the recovery of some goodly part of the testing gas, also the water employed to pressurize the gas is returnable to the water tank.
The background tools and apparatus hereinabove described are directed to testing for leakage the stands of pipe or tubing which can be handled by the drilling rig in building up a tubing spring, one stand at a time being assembled to the top, and then the whole string being lowered to make room for the addition of a successive stand.
This invention has application for occasions where it may be desirable to treat with a tubing string or casing, beginning far down in the well bore, or otherwise service a tubing string or a casing at a deep level, as for instance to plug or solidly close a perforated casing portion, as a perforated length of easing. In such cases it may not be desirable to have the packers widely separated, as one packer near the top of the well, and the other packer below the lowest point that may fall within the zone of test or treatment, but rather the packers should be spaced apart only a reasonably limited distance defined by the practicable length of tubing, casing or piping to be treated at one time.
As it is impracticable to have a tool head corresponding with the tool head 43, 44, to extend for a substantial distance above the upper packer 63, a tool head of an appropriate usable length may be provided above the upper packer 63, and from this tool head communication can be carried upwardly by two concentric pipes, with the outer pipe being of comparable dimension to the diameter of the spacer nipple or tubular barrel member 78 shown in FIG. 4C and FIG. 4D. Such outer pipe or tubular member obviously should be the member which extends the packer setting flow channel upwardly, since the fluid in this channel does not have to be expended each time the packers are deflated.
On the other hand the inner pipe, of the two concentric pipes which carry fluid communication upwardly from the packer setting and testing and/or treating tool, has very muchless volume or space therein, as it extends upwardly from the tool far down in the well bore. Thus since each time the packers are unset there must be lost all that fluid which filled the test, and/ or treatment space in the annulus between the packers, plus the fluid that runs down the testing and/ or treating flow channel before the packers and be reset, it follows that the inner pipe, of much smaller volume should comprise the test and/ or treatment fluid channel.
The combination tool 20 in part is shown extending above the top of the drilling rig floor 11 in FIG. 1; also the whole tool 20 is shown partially diagrammatically in FIG. 2 also the tool is shown completely in FIG. 3 and FIG. 3A, considered together; and furthermore the tool is shown in full section, from bottom to top, in FIG 4E, FIG. 4D, FIG. 4C; FIG. 4B and FIG. 4A. FIG. 4B, FIG. 41) and FIG. 40 have been hereinabove described, and the lower testing and/or treatment part of the tool is completed when the tool head 195, as shown in FIG. 4B
is substituted in place of the head portion 43, 44 shown in FIG. 4F.
In this construction, the tool head joins the lower tool head portion 44 in FIG. 4C, so that the test and/or treatment fluid passage 83a through the tool 20' includes the axial passage 84a through the head portion 195 which continues in FIG. 4C as the test fluid passage 84, hereinabove described. At the upper end of the axial passage 84a the inner pipe (or a hose) 193 is connected into the upper head portion 195 by a conventional connection fitting 194. The head portion 195 is turned down and externally threaded at its upper end 196 to have connected thereonto the lowest member of the outer tubing 197. Thus the test and/or treatment fluid arrives at the tool 42a through the pipe 193 and the packer setting fluid arrives through the annular space 198 comprising a part of the packer setting water course 61 and enters a flow channel 62a which communicates with the channel 62 in the head portion 44 of FIG. 4C, hereinabove described. An O-ring groove with an O-ring 199 is provided to seal against leakage between the tubing interior 198 and the tubing string or easing into which the tool 20 is inserted.
The tool 20 for deep testing and/or treating is assembled to be lowered into a tubing or casing string which is anchored below the drilling rig floor 11, and thus not shown in FIG. 1. One way of assembly would comprise first placing the tool 42a, hereinabove described, in the slips 19, shown in FIG. 1, and adding thereto a first inner stand of smaller tubing 193 and an outer stand of larger tubing 197, such being either connected to swivel means at the top thereof, or supported at the top in sleeve or bearing means in which the stands being added can turn, as an inner stand 193 is threaded up into the tool head 1%, and an outer stand 197 is threaded onto the tool head threaded end 196.
After the first concentric stands 197, 193 are added to the tool 42a, with the inner stand 193 to upstand slightly above the outer stand, the tool is lowered, as by the elevators 24, shown in FIG. 1, and the slips 18 are set to grasp the outer stand 197 near the top thereof. Then the successive concentric stands 197, 193 are picked up near the top of the derrick 13, with inner stand 197, as the bottoms of the concentric stands 197, 193, just above the slips 18. Then the supported inner tubing stand 193 is first added to the assembled inner tubing 193. Then the supported outer tubing stand 197 is lowered that slight amount to space its lowermost part, or pin end, adjacent the box end of the assembled stand 197 that is supported by the slips 18, and the pin end is stabbed into the box end, as is done conventionally in making up pipe strings. Thus the tool 29 is progressively assembled, with enough inner and outer stands 197, 193 being added to dispose the tool 42a approximate that predetermined level in the well bore just below which the tool 20 is to render a service.
The cross-over adapter 21, at first disassembled, has its uppermost member or connection head 200 set side, while its feed line adapter pin 202 is first inserted to pass downwardly through a bore 216 in the bottom of the channel nut or adapter head 22. Then the feed line adapter pin 202 is inserted over the upper, or pin end 203 of the inner tubing uppermost stand 193a, which extends above the top of the outer tubing uppermost stand 197a, as held in the slips 18. The adapter pin 202 has an O-ring groove and O-ring 204 in the lower end thereof to seal within the outer tubing 197.
Thereabove the adapter pin lower end portion 205 is externally threaded to be threaded into the upper or box end of the uppermost outer tubing stand upper end, and above the uppermost outer tubing stand 197a, the adapter pin 202 has a shank portion 206, with wrench flats 207 formed therein, to be grasped by wrench jaws of the wrench which threads the adapter pin 202 up into the tubing 197a.
As this is done the chamber nut or adapter head 22,
through the upper end of which the adapter pin 202 has first been inserted, has been held upwardly out of the way of the wrench action, and thus substantially in the relative position shown in FIG. 4A. After the adapter pin 202 has been installed, the chamber nut 22 is slid downwardly to rest upon the slips 18, not shown in FIG. 4A, but which support the tool 20 in its state of assembly, by grasping the uppermost outer tubing stand 197a. The spacer 208 is then placed in position on the adapter pin head 209, and then the connection head 200 is picked up and disposed so the threaded box 210 at the lower end of the central or high pressure or testing bore 211 therethrough, may be engaged with the pin end 203 of the inner tubing, uppermost stand 193a. While the connection head 200 is being threaded up on the inner tubing pin 203, a wrench may be inserted through the slot 212 in the spacer 208, to hold the inner tubing 193a against bending or tending to wrap upon itself. Then, the chamber nut or adapter head 22 may be raised upwardly and threaded upon the externally threaded lower part 213 of the connection head 200, while a wrench with opposed faces against the flats 207 of the adapter pin 202 holds the adapter pin 202 and the outer tubing stands 193a, 193 assembled therewith, from turning.
Thus, when the adapter head or connection head 22 completes assembly, there is tight, threaded engagement between adapter head 22 and connection head 200, so that the spacer 208 bears tightly against the under face of the connection head, while the bottom flange 214 of the chamber nut or adapter head 22 bears tightly against the underside of the adapter pin head 209. An O-ring groove and seal 215 is provided in the adapter pin head 209 to seal against leakage of the packer setting fluid, to be hereinbelow described, between the adapter pin head 209 and the chamber nut or adapter head 22 and its flange 214 to pass out the bore 216. Also, an O-ring groove and seal 217 is provided in the connection head 200 to seal against the aforesaid packer setting fluid leaking between the connection head and adapter head threads 213.
The cross-over adapter 21 includes a lug ring 217 to which a wire line or left cable 29 may be connected, as indicated in FIG. 1. Also, a flexible conduit, corresponding with the test and/or treatment fluid conduit 40b shown in FIGS. 1, 2, 3 and 6, is adapted to be connected into the drilled and tapped inlet 218, shown in FIG. 4A to deliver fluid by way of the lateral port 219 to pass down the aforesaid high pressure testing bore 211, and down the tubings 193a, 193 to the tool 42a, hereinbelow described. Also, a flexible conduit, corresponding with the packer setting fluid delivery conduit 40a, shown in FIGS. 1, 2, 3 and 6, is adapted to be connected into the drilled and tapped inlet 220, shown in FIG. 4A. to deliver fluid by way of the lateral port 221 to pass down the packer setting fluid bore 201 and into the chamber space 223 and through the adapter pin bore 222 to the annular space 198 between the inner tubings 193a, 193 and the inner wall surfaces of the outer tubings 197a, 197.
In case it may be preferable, and faster, to let the outer tubular members 197, 197a alone serve to space the crossover adapter tool 21 from the testing and/or treatment tool, while the inner member which supplies the test and/ or treatment fluid can comprise, between the upper and lower ends thereof, a flexible conduit or hose. In such case a modified tool 42b is provided having a modified tool head 195a as shown in FIG. 7. In this case the stands of tubing 197 are built up, a stand at a time, as hereinabove described, and with the uppermost stand 197a being held in the slips 18, the central conduit 193b is installed. Such central conduit 197b has a conventional pin end fitting 203 upper-most, correspondingly as shown in FIG. 4A, but the conduit below, and connected to the fitting 203 is flexible and of a predetermined length to reach down to the predetermined distance where the tool 42b is located. The lower end of the flexible conduit 197b terminates in, and is connected to, a hose end fitting 225 which in turn connects into a stab-in adapter 226. Such adapter 226 has an internally threaded, or box upper end 227 to receive the lowermost or pin member 228 of the conventional fitting 225 to which the bottom of the hose is connected.
The adapter or stab-in member 226 has a tapered or frusto-conical portion 229 below the central cylindrical upper body member, and below the tapered portion 229 it has a reduced diameter lower portion 230 terminating in a semi-spherical lower end 231. Centrally of the portion 229 an annular groove 232 between two longitudinally spaced apart upper O-rings 233a, 233b and two longitudinally spaced apart lower O-rings 233e, 233d, within the adapter portion 229.
The hose end fitting 225 has a central bore 234 which communicates with the interior of the hose thereabove and which communicates downwardly with a central bore 235 in the stab-in adapter 226. A lateral port 236 in the adapter 226 joins the axial bore 235 to the annular groove 232 therein, the outer part of the port 236 being plugged. The upper part a of the tool 42b is bored, countersunk at the bottom, counterbored, countersunk between bore and counterbore, and countersunk or dished on top to receive the stab-in adapter 226 therein, as shown in FIG. 7, the top countersunk surface 237 being an essential guiding surface to guide the adapter into place. The adapter also has a longitudinal bore 238a therein to communicate at its upper end with the lateral port 236, the lower end of the port being plugged; also a lateral bore 238b to intersect the longitudinal bore 238a, the outer end of the bore 238a being plugged; also the adapter 226 has an axial bore 83b, corresponding with the bore 84a in FIG. 4B, and with the bore 84 in FIG. 4C. The aforesaid bore 83b intersects upwardly with the lateral bore 238b. Additionally, the adapter 226 has an O- ring groove and O-ring 239 therein to prevent leakage between the lowermost tubing 197 and the threaded connection engagement between tubing and adapter. Also, the adapter 226 has a longitudinal bore 62b therein between the interior of the lowermost tubing 197 and the passage 62 in the tool part 44 therebelow, as shown in FIG. 4C.
The flexible tubing or hose, with the stab-in or stinger adapter 226 on the lower end thereof, may be paid off from a reel or winch drum, corresponding with the winch drum 30, and when the stinger or stab-in adapter 226 contacts the head 195a of the tool 4211 down in the well, it must be guided into a place by the dished surface or countersunk guide 237. At this point, with the fitting 203 installed on top of the hose, as it is held to upstand above the top stand 197a of the tubing, the adapter pin 202 may be inserted over the fitting 203, with the tool head or assembly nut 22 first slid down around the adapter pin 202. Then the feed line adapter pin 202 may be threaded up into the top stand of tubing 19711 by wrench engagement with the flats 207 as the tubing 197a is held. After this the spacer 208 may be inserted on top of the adapter pin head 209 to upstand thereabove, whereby a wrench may be inserted to hold the fitting 203 at the top of the hose or flexible tubing while the connection head 200 is tightened upon the fitting 203, and to seat upon top of the spacer 208. As the occurs it has been determined by precalculated measurement that there will still be some slight slack in the flexible tubing or hose, so that the stab-in adapter 226 remains firmly seated. Finally, the tool head or assembly nut 22 is lifted upwardly and then threaded upon the externally threaded portion 213 of the connection head 200, thus to complete the assembly of feed line adapter pin 202, tool head or assembly nut 22, spacer 208, and connection head 200.
With the tool 20a thus assembled with flexible hose replacing the small diameter tubing 193a, and the tubing 193 within the tubing 197a, 197, and with the structure of FIG. 7 replacing the structure of FIG. 4B (Fl-GS. 4C,
19 4D and 4E completing the tool), the assembled tool is ready for service.
Thus the conduits 40a and 40b may now be connected to the connection head 200, with the conduit 40b extending either from the needle valve 153 of console 28a, or from the valve 191 of console 28b, and with the conduit 40a extending from the needle valve 151 of either the console 28a or the console 2819.
As shown in FIG. 1 a truck 26 is shown to the left of the drilling rig floor 11 and set up to operate the testing and/or service tool 20, a. By this arrangement the tool 20 or 20a has been assembled, as aforesaid, to operate at a predetermined level or levels, below the surface, painstaking care having been taken to count the distance between the crossover tool 21 and the tool 42a, 42b hereinabove described which isolates a section of well bore tubing or casing at a predetermined level below the surface of the well. In this case, if water is to be the fluid to be used to set both the packers 63 and 64, and to carry out testing and/ or other operations, then the console 28a, in place on the drilling rig floor 11, may be used to direct the fluid into conduits 40a, 4%.
However, since inert gases, such as nitrogen, are more sensitive fluids, and more penetrative than water, and can be highly pressurized, this fluid may be preferable for use as the testing and/or high pressure treatment fluid, in which case a console 28b, also as shown in FIG. 1, may be lifted to the drilling rig floor 11, and disposed on the opposite side of the rotary table 19 from the console 28a, the nitrogen testing console 28b being equipped as hereinabove described, as regards the piping 144 shown in FIG. 6, and being additionally equipped with the additional piping 190 shown in dotted lines in FIG. 6, and as shown diagrammatically in FIG. 2, and in part in FIG. 1.
In FIGS. 1 and. 2 both consoles 28a and 28b are indicated as having been taken from the truck skid mount 36 and placed upon the drilling rig floor 11, as in ordinary usage, it will generally result that resting of the stands of a tubing string for leakage may 'be a major operation, but also special testing and/ or treatment, as at deep levels may be required, both preceding and after the regular tubing testing operations. Thus the two consoles 28a and 2812 may be used in series or in tandem. Also, it can occur that it may be desirable to use an inert gas, as nitrogen, to conduct the testing and/or other treatment operations, whereas the conventional oil rig circulating fluid or mud pump may be used to circulate the packer setting fluid.
Such a tandem or series arrangement of the consoles 28a, 28b is best shown in FIG. 2, and may be readily accomplished by providing, successively, between the T 147 and the T 150 of the piping 144a as shown for the console 28a in FIG. 6, a T 240, a valve 241, and a T 242. Then, from the open end leg of the T 242, a valve 243 may be installed, and from the central leg of the T 240, a valve 244 may be installed. Also, between the console 28a piping 144a, as shown in FIG. 6, a T 240, a valve 241, and a T 242 may be installed. Also from the open end leg of the T 242 a valve 243 may be installed, and from the central leg of the T 240, a valve 249 may be installed. Then a cross-connecting conduit 245 is extended between the valves 241 which completes the tandem connection of the consoles 28a, 28b for selective operation.
Also from the valves 243, 243 respective conduits 246, 246 extend to the opposed legs of a T 247, which has a valve 248 connected to the central leg thereof, the opposite side of the valve 248 being connected to one opposed leg of a T 249, the other leg of the T 249 being connected to the discharge outlet of a mud or circulating fluid pump 250. While the central leg of the T 249 has a valve 251 connected thereto, a discharge conduit 252 ordinarily carrying the circulating fluid or mud products onwardly, as to be recirculated back down into a well bore. Ordinarily the pump 250 picks up section products through a suction intake 253, as from a conventional mud pit at the top of a Well bore. However, in case of usage with this invention, the conduit 253 may be shifted to use any suitable packer setting fluid that may serve at the site of the well.
A special use of the tool 20 or 2011 is indicated in FIG. 2, where the tool 20 or 20a is of such length, as the tubing 197, 19711 spaces the cross-over adapter assembly 21 from the testing and/or treating tool 42a, that the tool 42a is spaced, as precalculated, in an area, within a casing 255, that has been perforated, as by the perforations 256, and where it may be desired to fill or plug the perforations. In this case, the distance between the packers 63, 64 has also been determined by the predetermined length of the tubing section 78, and thus the length of perforations 256 to be plugged at one setting of the packers may be determined.
The material to be used to plug the perforations 256 may be a light plastic which is supplied to the space 254 between the packers 63, 64 through the channel 83 and out the delivery port 87, as indicated in FIG. 2. For instance, the console 28a may be used, with a drum of plastic connected to the pump 37, the plastic drum being substituted for the auxiliary water reservoir 122 on the truck 26, to be kept in fluid, flowable state until used. In this case the pump 37 first takes suction from the water tank discharge outlet and delivers water through the conduit 39 and via the console 28a, thence by way of the flexible conduit 40a to the channel 61 as generally located in the tools 20 or 20a and 42a in FIG. 2. After the packers 63, 64 have been set, as hereinabove described, the valve 151 may be closed to lock the packers 63, 64 in set position. Then the valve 120a from the water tank 34 may be closed and the valve 121a opened to let the pump 37 take suction from the plastic, now indicated by the reservoir 122. The water that is downstream of the valves 120a, 121a, when they are respectively opened and closed, is drawn on through the pump 37 ahead of the plastic, and is pumped on through the console 28a, the console valves 244, 243, 151 and being closed, and the valve 153 being opened, and water thus precedes the plastic down the flexible conduit 40b and the channel 83 and out the discharge port 87 to fill the space 254 between the packers 63, 64, and then to be urged on, ahead of the plastic, through the perforations 256 in the casing 255. The water then is dispersed first into the formation on the immediate exterior 257 of the casing 255, and finally to be further displaced by the plastic into the formation 259 farther from the perforations 256.
The pump 37'continues to pump the plastic through the perforations until its movement is slowed and approaches a stop, as it clogs up and gums up the formation 257, immediately exterior of the casing 255, and begins to harden in the perforations themselves, all as indicated by an increase in the reading of the pressure gauge 148 at the console 28a.
If it is the object to use plastic successively, at level after level, or at several predetermined levels where the casing is known to be perforated, the following occurs. As the gauge 142 indicates a rise in pressure toward a predetermined limit indicating that the perforations will be plugged by the plastic (but while the highly pressurized plastic within the annulus 254 is still fluid), the valves 153 and 241 may be closed, and the valves 151 and 155 opened long enough for the packers 63, 64 to retract to permit the still fluid plastic in the space 254 to fall below by gravity. Then the valves 155 and 151 may be quickly closed, and the valves 153 and 241 quickly opened, while a purge fluid drum, as diesel fuel, replaces the plastic in the place of the reservoir 122, and is connected to discharge through the valve 121a and the line 121. Then the pump 37 may continue pumping long enough to purge the course of the plastic down through the channel 83 and out through the port 87.
Then the pump 37 may be stopped, and with the appropriate valves closed, the tool may be raised or lowered, as the case may be, to the next location of treatment. If
the tool 42a has been limited in length by a predetermined, short length tubing 78, and if the vertical interval between points of treatment is short, the tool may be lifted or lowered by the wire line 29, which is operated by the hoist 30 as controlled from the console 28a. If the tool is of considerable length, as limited by the tubing 78, so that the test and/or treatment space is of consider able length, then the change from station to station is effected by adding or subtracting a stand of tubing 197 at a time, to the distance between the cross-over adapter 21 and the tool 42a. In this case the inner tubing 193 (or hose terminating in the stab-in adapter 225), is correspondingly lengthened or shortened.
On the other hand it may be desired to leave the tool 42a (42b) in the well to serve at a predetermined level as a bridge plug. In this case, the plastic treatment proceeds, as hereinabove described, up to the point when the gauge 142 begins to show an increased reading. In this case the pump 37 is continued in pressurizing the plastic, the valve 151 remaining open, until the gauge 142 levels off at a relatively maximum reading. With this usage contemplated, the valves 151 and 153 are both closed, and the flexible conduits 40b, 40a are disconnected from the tool 21 at the top of the well, and the tool 21 is disassembled, so that the outer tubing 197a, 197 stands up above, and is held in the slips, and the inner tubing 193a, 193 stands up above the outer tubing 197a, 197, as indicated in FIG. 4A.
With the aforesaid usage contemplated, the internal threads 260 of the bore at the top of the tool head 195 in FIG. 4A are constructed so that if the inner tubing 193a, 193 is rotated in the left hand direction, as viewed from above, the fitting 194 disengages from the threads 260, while the inner tubing thereabove remains made up as to sections. Also, with the aforesaid usage contemplated, the external threads 196 of the upper portion 195 (195a) of the tool 42a (42b) are so formed that, if the outer tubing 197a, 197 is rotated in the left hand direction, as viewed from above, disengagement is made from the threads 196, while the outer tubing thereabove remains made up as to sections. On the other hand, with the aforesaid usage contemplated in the case of the tool 42b, the stab-in adapter 126 can be lifted out of the tool 42b, so no special threads are required.
Thus, in the case of the use of the tool 42b, the upper part of the hose terminating in the fitting 302 may be connected to a reel at the top of the well and the reel operated to recover the inner tubing (flexible hose). Then the outer tubing 197a, 197 may be withdrawn, stand by stand, in conventional manner.
There will thus remain in the well bore the tool 42a (42b) with the space between the packers 63, 64 and the tubing or casing 255 filled with hardened plastic. Also the lower channels 87, 86, 85, 84, 84a comprising the test and/or treatment flow channel 83a in FIG. 4C, FIG. B, or the lower channels 87, 86, 85, 84, 238b, 238a, comprising the test and/or treatment flow channel 83b in FIG. 4C, FIG. 7, are filled with hardened plastic. As to the packer channels, the retraction of the packer rubbers 94 result in the pistons 90, 110 moving respectively downwardly and upwardly, the packer setting water courses thus remaining closed as they would be in any event. Thus the tools 42a (42b) remain sealing the casing (or tubing) bore after the outer and inner tubings and adapter the 21 thereabove have been recovered.
In such case the plastic in the inner tubing 19311, 193 may run out into the casing (or tubing) 197a, 197 to harden and deposit upon the top of the tool 42a (42b), and thereafter the water that filled the annulus between inner and outer tubings, before their removal, may deposit upon the hardened lastic immediately therebelow and upon top of the now hardened plastic between the originally set packers 63, 64. In this manner the tool 42a (42b) remains 22 to seal the casing (or tubing) 255, and thus meets every requirement of a bridge plug.
It is noticeable in FIG. 2 that the drilling rig circulation or mud pump 250 may be cut in to pump at its greater delivery volume, as in cases where the truck 26 may be out of water and a source of water at the drilling rig 10 is to be used. Also such a pump 250 may be used when it is desired to fill substantial space hurriedly with a fluid, as water. This is obvious in FIG. 2, where the intake conduit 253 may be connected to any source of fluid, as water at the rig 10, or as water in the tanks 34 or 122 on the truck, conventional auxiliary connection outlets being provided for this purpose, but not being shown in FIG. 2.
In such case, if the rig pump 250 is to draw water from the water tank 34 on the truck 26, the truck pump 37 being cut out, a bypass valve 262 in the suction conduit 119 upstream from the pump 37 is closed, while a by-pass conduit 2.64 communicating with the suction conduit 119 upstream from the valve 262 has a valve 263 therein opened, the conduit 253 (or 39) to the suction inlet of the pump 250 being connected to the outer end of the by-pass conduit 264 on the truck 26. In this case, if the console 28a is being employed to set the packers of the tool in the Well bore, then the valves 243 and 244 of the console 28b are closed; also the valves 155, 153 and 244 of the console 28a are closed, while the valves 243, 241 and 151 of the console 28a are opened. Under this arrangement a T 145, in case of a recorder, is provided on either side of the T 247 above the valve 248 through which the pump 250 discharges, and also a check valve 146 in each of the conduits 2.46 is provided.
In this arrangement the pressure fluid delivered by the pump 250 registers against the fluid pressure gauge 148 of the console 28a. In case the console 28b is to be used in connection with the rig pump 250 the corresponding valves for right side operation, as hereinabove described for left side operation, are respectively opened and closed, while the appropriate left side valve are respectively closed and opened.
It should be noticed that with two consoles 28a, 28b on the rig floor, one console may be used for one purpose, as to set the packers, while the other console may be used for another purpose, as to test with nitrogen. For instance a case may be considered where a plastic has been pumped, as controlled by the console 28a, to plug the perforations 256 shown in FIG. 2, after which the packers have been retracted to let the plastic therebetween escape before the plastic can harden, and later it becomes desirable to test the plugged perforation area of the casing 255 for leakage. In 1115 case, at outset, the flexible conduit 40a is found I connected to the valve 151 of the console 2.8a, while the flexible conduit 40b is found connected to the valve 191 (ff thde 2conduit 28b, as indicated in dotted lines in FIGS.
Also, in the case set forth immediately hereinabove, the rig pump 250 may be connected to the outlet valve 121a from the auxiliary reservoir 122, or to any other source of packer setting water separate from the tank 34. On the other hand, the high pressure pump 37 on the truck 26 is connected to take suction via the suction conduit 119, from the tank 34 with discharge connection being made to the conduit 39 which extends for connection to the fitting of the console 28b.
By this manner of connection, the rig pump 250 can set the packers 63,64 of a tool 20, with cross-over adapter 21 at the top of the well, and with the testing and/or treatment tool 42a (42b) in the position indicated in FIG. 2, after the casing perforations 256 have been plugged by preceding operations.
Then the efiiciency of the plugging of the perforations 256 may be tested by employing nitrogen from the pressure vessel 178, pressurized by the water pumped thereto by the pump 37 via the conduit 182 and valve 181, as hereinabove described. Thus the pressurized nitrogen