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Publication numberUS3167127 A
Publication typeGrant
Publication dateJan 26, 1965
Filing dateApr 4, 1961
Priority dateApr 4, 1961
Publication numberUS 3167127 A, US 3167127A, US-A-3167127, US3167127 A, US3167127A
InventorsSizer Phillips S
Original AssigneeOtis Eng Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Dual well packer
US 3167127 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

Jan. 26, 1965 P. s. SIZER 3,137,127

DUAL WELL PACKER Filed April 4, 1961 2 Sheets-Sheet l INVENTOR Phillip S. Sizer BY WXfi ATTORNEYS Jan. 26, 1965 P. s. SIZER DUAL. WELL PACKER 2 Sheets-Sheet 2 Filed April 4, 1961 INVENTOR Phillip S. Sizer Fig. 9

Wflf/g g ATTORNEYS United States Patent 3,167,127 DUAL WELL PACKER Phillip S. Sizer, Dallas, Tex., assignor to Otis Engineering Corporation, Dallas, Tex., a corporation of Delaware Filed Apr. 4, 1961, Ser. No. 100,728 15 Claims. (Cl. 166-120) This invention relates to well tools and more particularly to dual string production packers.

An object of this invention is to provide a dual string production packer which can be set within a well casing or bore by means of hydraulic pressure without requiring movement of either tubing string.

Another object is to provide a dual string production packer for use in a well casing which will permit the circulation of fluids therepast after the Wellhead and surface connections have been installed.

Still another object is to provide a production packer for use with dual strings of tubing in a well casing which can be moved into sealing engagement with the casing and locked in such sealing position after the wellhead and surface connections have been installed.

A further object is to provide a production packer for use with dual tubing strings in the well casing of a well wherein the packer may be actuated by hydraulic pressure into sealing engagement with the casing and be held locked in such sealing position after the actuating hydraulic pressure is removed.

A still further object is to provide a production packer for use with dual tubing strings in the well casing of a well wherein the packer may be hydraulically set and locked in sealing position within the well casing after the wellhead and surface connections have been installed and wherein the packer will withstand large pressure differentials in either longitudinal direction of the casing.

A still further object is to provide a packer for use with dual strings of tubing in a well casing which is responsive to fiuid pressure in one of the strings to lock in sealing position between the well casing and tubing, and which may be unlocked from the sealing position and readily removed from the casing by manipulation of the tubing FIGURE 3 is a longitudinal sectional view as taken along the line 3-3 in FIGURE 7;

FIGURE 4 is a sectional view as taken along the line i-4 in FIGURE 1;

FIGURE 5 is a view showing the external surface of the lower portion of a latch mandrel of the well tool;

FIGURE 6 is a sectional view taken along the line 6--6 of FIGURE 2;

FIGURE 7 is a sectional view taken along the line 7--7 of FIGURE 1;

FIGURE 8 is a sectional view taken along the line 8-8 of FIGURE 2;

FIGURE 9 is a longitudinal sectional view taken along line 99 of FIGURE 4;

FIGURE 10 is a sectional view taken along the line 101 in FIGURE 1;

FIGURE 11 is a sectional view taken along the line 11-11 in FIGURE 1; and

FIGURE 12 is an elevational view partly in longitudibore 22a and the external wall of the mandrel 11. The r nal section, showing the lower portion of the well tool in anchored sealing position within a well casing.

Referring now particularly to FIGURE 1, the well tool or packer assembly 10 embodying the invention includes a pair of parallel spaced mandrels 11 and 12. A sub 13 provided with a bore 13a in its upper end portion for receiving the lower end of the mandrel 11 is connected to the mandrel by means of coacting threads 15 formed ex ternally on the mandrel 11 and internally on the sub 13.

The two mandrels are connected to one another and held in parallel spaced relationship by a cylindrical body 24 having a large circular coaxial bore 21 in its upper portion for encompassing both of the mandrels and a pair of smaller circular bores 22 and 23 in its lower portion. The smaller bores 22 and 23 communicate with the bore 21 and are of sufficient diameter to receive the mandrels 11 and 12, respectively, which are disposed therein. The external diameter of the cylindrical body is smaller than the internal diameter of the casing to permit free passage of fluid between the body and the casing wall. The axes of the smaller bores are parallel to and spaced from the axes of the cylindrical body.

The internal wall of the bore 23 has an annular groove in which is disposed an O-ring 24 to provide a fluid tight seal between the mandrel 12 and the cylinder body 20. The internal wall in the upper portion of the bore 23 is internally threaded to receive the externally threaded lower end of the mandrel 12.

' A bore 23a of a reduced diameter corresponding with the bore of the mandrel 12 extends coaxially from the bore 23 and forms an extension of the mandrel bore.

The bore 23a opens into a threaded socket 126 in the lower end of the cylinder body into which additional tubing may be joined.

A downward extension 22a of the bore 22 is found in the cylindrical body 20 and provided with a diameter larger than the external diameter of the mandrel 11 so that an annular space is formed between the wall of the bore 22a communicates with a recess 2% in the bottom of the body 26. The recess is provided with internal arcuate threads 27 in two of its walls for engaging external quarter threads 28 on the upper end of the sub 13 thereby forming a connection between the mandrel 11 and the A piston 30 having an external diameter slightly smaller than the diameter of the bore 21 of the cylindrical body 20 so as to be slidably received therein is provided with a pair of circular bores 31 and 32 which slidably receive the parallel'mandrels 11 and 12, respectively. The bottom surface of the piston which is slidable along the mandrels, is adapted to abut the upwardly facing surface 21a which defines the bottom of the bore 21 body 20.

An O-ring 33 disposed in an annular groove formed in the wall of the bore 31 seals between the mandrel 11 and piston 30 and an O-ring 34 disposed in an annular groove in the wall of the bore 32 seals between the mandrel 12 and piston 30. A seal between the 'piston and the cyl- =bers 37 and 38 are formed about the mandrels at the lower end of the piston which, due to the provision of the O-rings 33, 34 and above the chambers and the lower O-rings 29 and 24 are fluid-tight. An aperture or lateral port 40' of the mandrel 12 communicates with the interior of the mandrel 12 and the chamber 38. Thus,

Patented Jan. 26, 1965 in the cylindrical 1 of slightly enlarged di- '0 e13 it may' readily be seen that fluid pressure introduced to the mandrel 12 will move the piston upwardly relative to the cylinder 20 and the mandrels 11 and 12.

A lower slip expander 41 is slidably disposed about the two mandrels 11 and 12 above the piston and is secured to the mandrels by shear screws 42. The slip expander has an external diameter corresponding to the external diameter of the lower cylinder 20 and is provided with parallel bores 43 and 44 through which extend the mandrels 11 and 12, respectively.

The lower portion of the bore 44 is enlarged to provide a beveled cam surface 45 which is engaged by slip segments 46. The outer surfaces 47 of the slips are beveled to conform to and engage the cam surface 45 while their inner surfaces are provided with teeth 48 for engaging the mandrel 12. A circular retainer plate 50 interposed between the lower end of the slip expander and the upper end of the piston, is provided with a pair of bores for receiving the mandrels about which it is slidably disposed. The bore for accomodating mandrel 12 is enlarged at its upper end portion to form an annular groove in which is disposed a wave spring 57 for biasing the slips upwardly into engagement with the cam surface 45. These slips permit the slip expander to move upwardly on the mandrel 12, as when it is moved upwardly by the piston 30 with a force sufiicient to shear the screws 42, but will not permit any relative movement in the opposite downward direction because of the gripping action of the teeth 43 of the slips.

Expansible, resilient sealing elements 51, 52 and 53 are slidably mounted on the parallel mandrels above the slip expander and are confined between element caps 54a and 54b. The sealing elements have en external diameter equal to the external diameters of the expander 41 and cylinder 29 and are provided with suitable bores for receiving the mandrels 11 and 12.

The upper cap 54a abuts the lower surface of the slip carrier 55 slidably disposed on the parallel mandrels but releasably held in the lower position illustrated in FIG- URE l by a shear screw 56 which extends through a suitable threaded bore of the slip carrier into a similar bore in the mandrel 12. When fluid pressure in the bore of the mandrel 12 isincreased to shear the screws 42 and move the piston upwardly, the sealing elements move upwardly until the cap 54w engages the slip carrier 55. Further upward movement of the piston then causes the sealing elements to expand laterally to engage the inner wall of the surrounding well casing and close off the space between the mandrels and the casing. After the slip expander41 has been moved upwardly, any downward movement of the expander is arrested by the slips whose teeth 48 move into engagement with the outer surface of mandrel 12 due to the camming action between the cam surface 45 of the expander and the surfaces 47 of the slips. The sealing elements will thus be locked in their expanded casing engaging position.

The slip carrier 55 is provided with upwardly opening T-slots 55a which receive the T-handles 60a of the slips 60. A slip mandrel 61 which is slidably disposed about the parallel mandrels 11 and 12 is provided with dovetailed slots 61w which are inclined downwardly and inwardly and mate with dovetails 62 of the slips 60. As shown in FIGURE 9, the inner surfaces 63of the slip carrier are inclined downwardly and inwardly and are engaged by the surfaces 64 of the dovetails.

the slip carrier the slips are expanded outwardly into casing engaging position and when the slip mandrel As a result; when the slip mandrel 61 moves downwardly relative to moves upwardly the slips are retracted. The slip mandrel tion of its axial bore is of an enlarged uniform diameter for accommodating a cylindrical thrust bearing 66 which is disposed between the mandrel and the inner wall of the enlarged port-ion of the bore for reducing rotational friction between the upper slip expander and the slip mandrel 61. The upper portion of the axial bore is flared upwardly and outwardly to provide a beveled cam surface 66a which engages the outer surfaces 67a of the slips 67 which are inserted between the mandrel 11 and the cam surface. The slips 67 are identical to the slips 46 but are inverted relative thereto, having teeth 68 which engage the outer surface of the mandrel 11. A retainer ring 70, provided with a pair of bores for accommodating the mandrels 11 and 22 which extend therethrough, is disposed about the mandrels in abutting engagement with the top end surface of the slip expander 65. A wave spring 71 disposed in an annular recess 72 formed in the under surface of the retainer ring, biases the slips 67 into intimate contact with the mandrel 11 at all times.

A slip housing 75 partially surrounds the upper slip expander 65 and the mandrel 12 and serves as a spacer between the retainer ring 70 and the slip mandrel 61. The mandrel 12 and the slip expander 65 extend through circular bores in the housing which are of substantially equal diameter with the mandrel and the expander respectively. In order to maintain the wave spring, slip expander, slips, and thrust bearing in their proper relative positions, cap screws are provided for locking the retainer ring, slip housing, and slip mandrel in fixed positions, such cap screws extending downwardly through suitable bores in the retainer ring and slip housing into upwardly opening threaded bores of the slip mandrel.

An up er cylindrical body is slidably disposed about the mandrel 11, the mandrel extending through a longitudinal bore of the body. A circular bore 81 coaxial with the mandrel 12 is formed in the body 80 for receiving the upper end of the mandrel 12. An O-ring 82 disposed in an annular groove in the wall of the bore 81 provides a fluid-tight seal between the mandrel and the cylindrical body 80. Upward movement of the mandrel 12 in the bore is limited by the engagement of its upper end with the lower annular shoulder of the internal flange 83.

A bore 84 of'a diameter larger than the diameter of the bore 81 is formed in the cylinder body 80 above the flange 83 and co-axial with the bore 81 for receiving a tubular latch mandrel 85. The latch mandrel is provided with a central longitudinal bore of a diameter substantially equal to the internal diameters of the flange 83 and the mandrel 12, respectively, and is also provided with an external annular flange 85a intermediate the ends thereof of an external diameter substantially corresponding with the diameter of the bore 84 soas to be slidably received therein. A V-packing assembly 87 on the latch mandrel above the flange 83 seals between the upper portion of the latch mandrel and the internal wall of the bore 34 in the cylindrical body 86.

The latch mandrel is latched to the cylindrical body 80 by means of transverse anchor pins 88 threaded into transverse openings 90 in the cylindrical body 80 extending into the bore 84, as shown in FIGURE 10. The ends of the anchor pins engage in J slots 91 formed in the external surface of the lower portion of the latch mandrel. O-rings 92 disposed in external annular grooves of the pins 88 engage the cylindrical body 80 to prevent the leakage of fluids past, the pins through the openings 90.

The cylindrical body 80 has a pair of equal diameter circular bores 95 which extend an equal distance into the body 80. The axes of the bores are parallel to the axes of the body 80 and the mandrels 11 and 12 and are diametrically opposed relative to the axis of the body 80. Each of the bores 95 is in fluid communication with the bore 84 by means of a passage 96 in the body 80 extending from the upper end of the bore 95 to the bore 84. Disposed in reach of the bores 95 is a piston 97 having an external annular groove 98 in which is disposed an O-ring 99 for sealing between the piston and the wall of the bore 95. Above the piston, which is of equal length with the bore 95, is a conical chamber 101) defined by a conical surface formed in the end wall of the bore and closed by the piston head. Fluid pressure may be introduced from the bore 84 and slots 96 into the chambers and force the pistons 97, the upper slip housing 75, and slip mandrel 61 downwardly relative to the slips 60 and mandrel 11 and 12 to force the slips 60 utwardly into intimate contact with the inner wall of the well casing and thus lock the packer device therein.

The upper end portion 105 of the mandrel 11 is enlarged to provide a downwardly facing external annular shoulder 106 which engages the internal annular upwardly facing shoulder 107 in a bore 168 of a guide 110. The guide 110 rests upon the upper end of the cylindrical body 31) and is also provided with a circular bore 113 in axial alignment with the bore 84- of the cylindrical body 81) and maintained in alignment therewith by means of cap screws 111 which extend through suitable bores of the guide into threaded bores in the body 80. The guide surface 112 is flared upwardly and outwardly from the bore 113 to form a funnel whereby the lower end of latch mandrel 85 will be guided into the bore 113, and therefore the bore 84, when lowered thereinto.

In use, the packer is lowered from the surface into the well casing on a first tubing string 115 to' which it may be attached by threads 116 formed in the upper end portion of the mandrel 11 which engage with the external threads at the lower end of the tubing string. Additional tubing may be suspended from the lower sub 13 by means of the threads 117 on the lower end of the sub. Additional tubing, perhaps including a special landing nipple, may

also be suspended on the packer parallel with the tubing attached to the lower end of the sub 13 by means of i the threaded socket 26 at the lower end of the cylindrical body 20.

A second string of tubing 115a, whose lower end is threaded into the upper end of the sub 120 whose lower end, in turn, is threaded on the upper end of the latch mandrel 85, and the latch mandrel 85, are then lowered into the well casing until the latch mandrel contacts the guide 110. At its lower end, the latch mandrel is provided with a bevel which coacts with the bevel or cam surface 112 of the guide to guide or move the latch mandrel into the bore 84. Therefore, should the extreme lower end of the latch mandrel become lodged atop the guide 110, all that is required to dislodge the mandrel is to rotate this second tubing string slightly to the right. When the bevel 125 contacts the flared portion 112 of the bore 113 in the guide 111), the latch mandrel will readily enter the bore 113 of the guide and the bore 84 of the cylindrical body 81).

As the latch mandrel is lowered into the bore 84, the cam surface 12-6 or 127 defining the J slots, shown in FIGURE 5, will contact the inwardly projecting ends of the anchor pins 88 and will cause the latch mandrel and the tubing string 115a to rotate slightly to the right or left so that the anchor pins will be conducted to the uppermost portions of the J slots. When this occurs, the tubing string 115a is lifted until the anchor pins enter into the lowermost portions 91a of the vertical sections of the J slots. The tubing is then suspended from the surface. The tubing string is preferably supported in tension, but it may be suspended in compression, if desired, in which case the projections of the anchor pins 88 will occupy the uppermost portion of the J slots 91.

After both strings of tubing have been set in place within the well bore and the well surface connections have been installed, fluids may be circulated around the packer through the well casing, if desired, and in either direction. Thus, drilling mud may be displaced from the tubing after the surface equipment has been installed.

The packer may then be set in the well casing by introducing fluid pressure to the second string of tubing after first plugging its bore at a point somewhere below the port 40 of the mandrel 12. This may be accomplished by lowering a suitable plug through the tubing to a suitable landing nipple connected in the tubing whose upper end may be secured to the body 20 by means of the socket 26. Fluid pressure within the second tubing string is then communicated to the chamber 100 through the slots 96 to apply a downward force to the piston. The pistons move the retainer ring 70 and the slip mandrel 61 downwardly and the slips 60 outwardly to lock the packer in the. well casing when the shear screws 164 shear to permit downward movement of the slip mandrel. At the same time, the fluid pressure within the second tubing string is transmitted through the port 40 to act against the lower side of the piston 30 to tend to force the slips 46 upwardly and the sealing elements 51, 52, and 53 into compression but the shear screws 42 prevent upward movement of the expander 41 and the piston 40. i

The shear screws 164, being of lesser shear strength than the shear screws 42, will shear first, whereupon the fluid pressure acting on the piston 97 will force the retainer ring 70, upper slip housing 75 and the slip man drel 61 downwardly, thereby expanding the slips 60 into engagement with the inner wall of the casing. During downward movement of the slip mandrel 61, movement of the slips 60 and slip carrier 55 is prevented by the shear screw 56.

As the pistons move the retainer ring 70 downwardly, the upper slip expander 65 also is moved downwardly, together with the thrust bearing 66 and slip segments 67. When the slips 60 have been fully expanded, or expanded as far as permitted by the well casing, the slips 67 engage the outer surface of the mandrel 11 and, due to the cam action of the surface 66a of the expander, loch the packer against upward movement in the well casing.

After the packer is locked securely in the well casing, pressure in the second tubing string is gradually increased until, when it reaches a sufiicient value, the shear screws 42 are sheared, permitting the piston 31) to move upwardly in response to the pressure transmitted thereto through the port 40.

As the piston 30 moves upwardly, it applies a compressive force to the sealing elements 51, 52, and 53 through the retainer plate 50 and the lower slip expander 41. The slip carnier 55 being held stationary by the shear screw 56 relative to the mandrels 11 and 12, upward movement of the piston 30, and therefore the lower slip expander 41, causes the sealing elements to expand laterally into. sealing engagement with the well casing. As the sealing elements are thus compressed, the element caps 54a and 54b are expanded to bridge or partially bridge the annular opening between the packer and the casing to prevent extrusion of the resilient sealing elements.

During the compressing of the sealing elements, the screw 56 which holds the slip carrier 55 in place relative to the mandrel 12 may possibly shear even though the screw has a greater shear strength than the shear screws 42. The possible shearing of the screw 56, however, is of no consequence, since the slips 61 are in flocked engagement with the slip expander so that the slip carrier 55 could move upwardly only a very limited distance. The counterbore 130 of the slip carrier into which the snap ring 131 projects is deepened to provide clearance for such possible upward movement of the slip carrier. The snap ring 131 is received in an annular external groove of the mandrel 11.

When fluid pressure within the mandrel 12 is released, the compressed sealing elements force the lower slip expander downwardly a very slight distance, thereby camming the slips 46 inwardly and locking the expander against further downward movement. The packer is thus locked and sealed within the well casing and is adapted to withstand substantial pressure differentials in either longitudinal direction. Of course, the plug which was previously placed below the port 40 to allow a buildup of fluid pressure within the tubing string may then be removed.

. It will be noted that if fluid pressure in the casing above the packer is greater than the pressure below, the differential pressure acting downwardly on the sealing elements is transmitted through the slips 46, the mandrel 12, the lower cylindrical body 20, the mandrel 11, the slips 67, the'upper slip expander 65, to the slip mandrel 61, and through slips 60 to the well casing. Also a pressure differential acting in the opposite direction exerts an upward force on the slip carrier 55 and is resisted by the screw 56 (if it has not sheared) or transmitted to the casing through the slips 60. Thus, it will be seen that a differential pressure acting in either direction tends to lock the packer more securely in the casing.

a In similar manner, forces due to compression or tension of either of the tubing strings are likewise transmitted to the well casing when the packer is locked therein. Compressive forces of the tubing string are transmitted to the upper cylindrical body 80, the mandrel 12, the lower cylindrical body 20, the mandrel 11, the upper slips 67, the slip mandrel 61, and through the slips 6f) to the well casing. Forces of tension in the tubing strings are transmitted to the lower cylindrical body 20, either from the first tubing string 115 or from the second tubing string, connected to the top sub 120, through the upper cylindrical body 80, and mandrel 11, and thence to the casing through the mandrel 12, the slips 46, the lower slip expander 41, the resilient elements 51, 52, and 53, the slip carrier 55 and the slips 60 to the well casing.

It will be apparent that the dual string production packer, disclosed herein, will permit the circulation of fluids therepast after the wellhead and surface connections have been installed.

It will also be seen from the description that a dual string production packer has been provided which may be set in a well casing without requiring manipulation of either of the tubing strings.

It will further be seen that whereasthe packer may be set by introducing fluid pressure into a tubing string, it is maintained locked in casing engaging position by mechanical means independently of the maintenance of the fluid pressure in such tubing string.

To remove the packer from the well, the second tubing string which is connected to the top sub 120 is first unlatched therefrom by lowering the tubing string slightly and then rotating the string in a clockwise direction. The pins 88 which latch the latch mandrel 85 to the mandrel 12 are thereby disengaged from the J slots in the latch mandrel so that the second tubing string with the attached latch mandrel is freed to be lifted and removed from the well.

-To remove the first tubing string 115 and the packer from the well, the tubing string is first rotated a quarter turn in the clockwise direction to disconnect the lower sub 13 from the lower cylindrical body by disengaging the breech lock thread 28 from the thread 27 as shown in FIGURE 8. At the end of a quarter turn, the thread 28 of the mandrel 11 engages the stop 20a threaded in an aperture in the cylindrical body 20 and extending into the recess 20b whereupon further rotation of the mandrel is prevented. Rotational friction between the packer and mandrel 11 during such rotation is reduced by the thrust bearing 66 contained within the slip expander 65. The first tubing string 115 and the attached mandrel 11 are then lifted a distance sufficient to permit the breech lock thread 28 to clear the corresponding thread 27, whereupon the mandrel may then be rotated freely through any number of revolutions relative to the body 29 if desired.

Further lifting of the tubing string then brings the snap ring 131, which is disposed in groove 132 of man drel 11, into contact with the lower end of the slip mandrel 61. Continued upward movement of the string and mandrel then lifts the slip mandrel 61 and retracts the slips 6% due to co-action of the dovetails and slots of the slips and slip mandrel, respectively. When the slips 60 are fully retracted and cannot be further moved inwardly, the force caused by the lifting of the tubing string will then be transmitted to the slip carrier 55, thereby moving it upwardly on the mandrels and shearing the screw 56, if it has not already been sheared. The resulting upward displacement of the slip carrier relative to the mandrel 12 and the slip expander 41 held fixed thereon provides space for the resilient sealing elements to decompress and break the seal between the packer and the well casing. Also, after the slip mandrel 61, the slip housing and the retainer ring 70 have been lifted to the positions shown in FIGURE 1, further lifting of the tubing string causes the upper cylindrical body to move upwardly relative to the mandrel 12. Mandrel 11 may thus be lifted until the uppermost end of the lower sub 13 engages the downwardly facing shoulder 133 of the lower cylindrical body 20, whereupon the slips having been retracted from engagement with the well casing and the sealing elements having been released from scaling position with the casing, the packer may be removed from the well by lifting the tubing therefrom.

. It will thus be seen that a dual string production packer has been provided which may be connected in the tubing strings and hydraulically set by introduction of fluid pressure in one of the strings.

It will also be seen that a dual string production packer for use in well casing has been provided which may be locked and sealed within the well casing after the wellhead and surface connections have been installed.

It will further be seen that the dual string production packer disclosed herein is adapted to withstand large pressure differentials or column loads in either direction of the well bore. It can be set without requiring manipulation of either of the tubing strings and is readily removable from the well casing.

The foregoing description of the invention is explanatory only, and changes in the details of the construction illustrated may be made by those skilled in the art, within the scope of the appended claims, without departing from the spirit of the invention.

What is claimed and desired to be secured by Letters Patent is: I

l. A well packer including: a pair of mandrels, each having a passageway extending therethrough; upper and lower body members connecting the opposite ends of said mandrels to each other; anchoring means on said mandrels movable relative to said mandrels between a retracted position and an expanded operative position wherein said anchoring means is engageable with the internal surface of a well casing to hold the mandrels against movement relative to said casing; means on said mandrels operable in response to fluid pressure in one of said passageways for moving said anchoring means to said operative position; first conduit means on said mandrels for communicating fluid pressure from said one of said passageways with said means for moving said anchoring means for moving said anchoring means to operative position; first lock means on said mandrels for locking said anchoring means in said operative position; seal means on said mandrels; operating means on said mandrels operable in response to fluid pressure in one of said passageways for moving said seal means to a position of sealing engagement with the internal surfaces of a well; second conduit means on said mandrels communicating one of said mandrel passageways with said operating means for moving said seal means for conducting fluid pressure to said operating means from said passageway for operating said operating means; and second lock means on said mandrels for locking said sealing means in said sealing position.

2. A dual string well packer for use with dual tubing strings in a well comprising: a pair of mandrels, each having a passageway extending therethrough; upper and lower body members connecting the upper and lower ends of said mandrels and having passageways therein receiving said mandrels; means for connecting each said mandrel to a diflerent one of said tubing strings wherein the passageway of each mandrel is in fluid communication with the bore of the tubing string to which it is attached; anchoring means on said mandrels movable on said mandrels between a retracted position and an operative position wherein said anchoring means is engageable with the internal surfaces of a well casing to hold the mandrels against movement relative to said casing; means on said mandrels operable in response to fluid pressure in one of said passageways for moving said anchoring means to said operative position; first conduit means on said mandrel for communicating fluid pressure from said one of said passageways with said means for moving said anchoring means to operative position; first lock means on said mandrels for locking said anchoring means in said operative position; seal means on said mandrels; operating means on said mandrels operable in response to fluid pressure in one of said tubing strings for moving said seal means to a position of sealing engagement with a well casing; second conduit means on said mandrel communicating said one of said passageways with said operating means for moving said seal means for conducting fluid pressure to said operating means for said passageway for operating said operating means; and second lock means on said mandrels for locking said sealing means in said sealing position.

3. A well packer including: a pair of mandrels, each having a passageway extending therethrough; upper and lower body members spaced longitudinally from each other connecting said mandrels to each other and having a pair of passageways therein for receiving said mandrels; anchoring means on said mandrels movable relative to said mandrels between a retracted position and an expanded operative position wherein said anchoring means is engageable with the internal surfaces of a well casing to hold the mandrels against movement relative to said casing; expander means on said mandrels movable longitudinally relative thereto between an initial position and a second position, means operatively connecting said anchoring means and said expander means whereby said anchoring means is held in retracted position by the expander means when the expander means is in initial position, said expander means moving the anchoring means to operative position upon movement of said expander means from said initial position toward said second position; fluid pressure actuated operating means on said mandrels operable by fluid pressure conducted thereto from one of said passageways of said mandrels for moving said expander means relative to said anchoring means to expand said anchoring means to anchoring positions; first conduit means on said mandrels for conducting fluid pressure from said one of said passageways to said operating means for operating said expander means; first lock means on said mandrels for locking said anchoring means in said operative position; seal means on said mandrels; second operating means on said mandrels operable in response to fluid pressure in one of said passageways for moving said seal means to a position wherein said seal means is in sealing engagement with the internal surfaces of a well; second conduit means on said mandrels communicating said second operating means with one of said mandrel passageways for conducting pressure of fluicl from said one of said mandrel passageways to said second operating means for operating said second operating means to move said seal means to sealing position; and second lock means on said mandrels for locking said sealing means in said sealing position.

4. A dual string well packer for use with dual tubing strings in a well comprising: a pair of mandrels, each having a passageway extending therethrough; upper and lower body members connecting the upper and lower ends of said mandrels to each other; means for con necting each said mandrel to a different one of said tubing strings wherein the passageway of each mandrel is in communication with the bore of the tubing string to which it is attached; anchoring means on said mandrels movable between a retracted position and an operative position wherein said anchoring means is engageable with the internal surfaces of a well casing to hold the mandrels against movement relative to said well casing; expander means on said mandrels and operatively connected with said anchoring means, said expander means being movable relative to said mandrels and said anchoring means between an initial position wherein said anchoring means is held in retracted position by said expander and a second position, said anchoring means being moved to operative position by said expander means upon movement of said expander means toward said second position; first fluid pressure responsive means on said mandrels operable for moving said expander between said initial and said second positions; first conduit means on said mandrels communieating said pressure responsive means with one of said passageways of said mandrels for conducting fluid pressure from such passageway to said fluid responsive means for actuation thereof; first lock means on said mandrels for locking said anchoring means in said operative position; seal means on said mandrels; operating means on said mandrels operable in response to fluid pressure in one of said tubing strings for moving said seal means to a position of sealing engagement with a well casing for sealing therebetween; second conduit means on said mandrels communicating said one of said passageways with said pressure responsive operating means for operating said pressure responsive operating means to move said seal means to sealing position; and second lock means on said mandrels for. locking said sealing means in said seal ing position.

5. A dual string well packer for use with a well comprising: a pair of mandrels, each having a passageway extending therethrough; upper and lower body members connecting the upper and lower ends of said mandrels together; anchoring means on said mandrels movable between retracted position wherein the anchoring means is adjacent the mandrels and expanded position wherein said anchoring means is remote from the mandrel and engageable with the internal surfaces of a well to hold the mandrels against movement relative thereto; first means on said mandrels operable in response to fluid pressure in one of said passageways for moving said anchoring means to said expanded position; first conduit means on said mandrels communicating said one of said passage ways with said first pressure responsive means for coning means limiting movement of said seal means on said ing means limiting movement of said seal means on said mandrels; second means on said mandrels operable in response to fluid pressure in one of said passageways for a moving said seal means into a position of sealing engagement with the internal surfaces of a well by compressing said seal means against said anchoring means; second conduit means on said mandrels communicating said one of said passageways with said second pressure responsive means for actuating said pressure responsive means to move said seal means to sealing position; and second lock means on said mandrels for locking said seal means in said sealing position.

6. A dual string well packer for use with dual tubing strings in a well comprising: a pair of mandrels, each having a passageway extending therethrough; upper and lower 1 ll body members spaced longitudinally from each other connecting said mandrels to each other and having a pair of passageways therein receiving said mandrels; means for connecting each said mandrel to a different one of said tubing strings wherein the passageway of each mandrel is in fluid communication with the bore of the tubing string to which it is attached; anchoring means on said mandrels movable between retracted position wherein the anchoring means is adjacent the mandrel and expanded position wherein said anchoring means is remote from the mandrel and engageable with the internal surfaces of a well to hold the mandrels against movement relative thereto; first means on said mandrels operable in response to fluid pressure in one of said tubing strings for moving said anchoring means to said expanded position; first conduit means on said mandrels communicating said first pressure responsive means with said one of said passageways of said mandrels for conducting said fluid pressure from said one of said passageways to said first pressure responsive means for moving said anchoring means to expanded position; first lock means on said mandrels for locking said anchoring means in said expanded position; expansible seal means disposed on said mandrels adjacent said anchoring means, said anchoring means limiting movement of said seal means on said mandrels; second means on said mandrels operable in respose to fluid pressure in one of said tubing strings for moving said seal means into a position of sealing engagement with the internal surfaces of a well by compressing said seal means against said anchoring means; second conduit means on said mandrels communicating said second pressure responsive means with said one of said passageways of said manrels for conducting fluid pressure from said one of said passageways to said second fluid pressure responsive means for operating the same to move said seal means to sealing position; and second lock means on said mandrels for locking said seal means in said sealing position.

7. A dual string well packer for use with a well having well casing comprising: a pair of mandrels each having a flow passage therethrough; upper and lower body members spaced longitudinally from each other connecting the upper and lower ends respectively of said mandrels, said body members having passageways therein receiving said mandrels; anchoring means on said mandrels movable between retracted position wherein the anchoring means is adjacent the mandrel and expanded position wherein said anchoring means is remote from the mandrels and engageable with the internal surfaces of said well casing to hold the mandrels against movement relative to the well casing; first expander means on said mandrels movable longitudinally relative thereto, between an initial position and a second position, said first expander means operatively engaging and moving the anchoring means to said expanded position upon movement of said first expander means toward said second position; first fluid pressure responsive means on said mandrels for moving said first expander means toward said second position; first conduit means on said mandrels communicating said first fluid pressure responsive means with the flow passage of one of said mandrels for conducting fluid pressure from such flow passage to said first pressure responsive means for moving said expander means toward said second position; first lock means engageable with said first expander means and said mandrels for locking said first expander means in said second position; expansible seal means disposed on said mandrels adjacent said anchoring means, said anchoring means limiting movement of said seal means on said mandrels; second expander means on said mandrels movable longitudinally relative thereto for moving said seal means to a position of sealing engagement with the well by compressing said seal means against said anchoring means; second fluid pressure responsive means on said mandrels operatively connected with secondexpander means for moving said second expander means longitudinally relative to said mandrels to move said seal means to sealing position; second conduit means on said mandrels communicating between one of said flow passages of said mandrels and said second fluid pressure responsive means for conducting fluid pressure from said flow passage to said second fluid pressure responsive means to actuate the same in response to such fluid pressures; and second lock means on said mandrels engageable with said mandrels and said second expander means for locking said seal means in said sealing position.

8. A dual string well packer for use with dual tubing strings in a well comprising: a pair of mandrels, each having a passageway extending therethrough; upper and lower body members spaced longitudinally from each other connecting the upper and lower ends respectively of said mandrels, said body members having passageways therein receiving said mandrels; means for connecting each said mandrel to a diflerent one of said tubing strings wherein the passageway of each mandrel is in fluid communication with the bore of the tubing string to which it is attached; anchoring means on said mandrels movable relative to said mandrels between a retracted position and an operative position wherein said anchoring means is engageable with the internal surfaces of said well to hold the mandrels against movement relative to the internal surfaces of said well; first means on said mandrels operable in response to a first lower fluid pressure in one of said passageways for moving said anchoring means to said operative position; first conduit means on said mandrels for conducting fluid pressure from said one passageway to said first means for actuating the same; first lock means on said mandrels for locking said anchoring means in said operative position; seal means on said mandrels adjacent said anchoring means, said anchoring means limiting movement of said seal means on said mandrels; second means on said mandrels operable in response to a second higher fluid pressure in one of said passageways for moving said seal means into a position of sealing engagement with the internal surfaces of said well by compressing said seal means against said anchoring means; second conduit means on said mandrels communicating said one of said passageways with said second means for conducting said second higher fluid pressure to said second means for moving said seal means to sealing position; and second lock means on said mandrels for locking said seal means in said sealing position.

9. A dual string well packer for use with dual tubing strings in a well having well casing comprising: a pair of mandrels, each having a bore extending therethrough; upper and lower body members spaced longitudinally from each other connecting the upper and lower ends respectively of said mandrels, said body members having passageways therein receiving said mandrels; means for connecting one or" said mandrels to one of said tubing strings with their bores in fluid communication; a latch member secured to the other of said tubing strings for latching said other tubing string to said upper body member in flow communication with the bore of said other packer mandrel; anchoring means on said mandrels movable between a retracted position wherein the anchoring means is adjacent the mandrels and expanded position wherein said anchoring means is remote from the mandrels and engageable with the internal surfaces of a well casing to hold the mandrels against movement relative to said casing; expander means on said mandrels movable longitudinally relative thereto between an initial position and a second position, said expander means operatively engaging said anchoring means for moving the anchoring means to said expanded position upon movement of said expander means to said second position; first operator means on said upper body member responsive to fluid pressure in said other tubing string when said latch member latches said other tubing string to said other packer mandrel to move said expander means 7 .to said second position, thereby moving said anchoring means to expanded position; first conduit means on said upper body member communicating said first operator means with said other tubing string for conducting fluid pressure from said other tubing string to said first operator means to move said expander means toward said second positions; seal means on said mandrels; second operator means on said mandrels operable in response to fluid pressure in said other tubing string for moving said seal means to a position of sealing engagement with the well casing for sealing therebetween; second conduit means on said mandrels communicating said other tubing string with said second operator means for conducting fluid pressure from said other tubing string to said second operator means for moving said seal means to sealing position; and lock means on said mandrels for locking said sealing means in said sealing position.

10. A well packer including: a plurality of mandrels, each having a passageway extending therethrough; upper and lower body members spaced longitudinally from each other connecting the upper and lower ends respectively of said mandrels, said body members having passageways therein receiving said mandrels; anchoring means on said mandrels movable relative to said mandrels between a retracted position and an expanded operative position wherein said anchoring means is engageable with the internal surface of a well casing to hold said mandrels against movement relative to said casing; first operator means on said mandrels operable in response to fluid pressure in one of said passageways for moving said anchoring means to said operative position; first conduit means on said mandrels communicating said first operator means with said one of said passageways for conducting fluid pressure from said passageway to said first operator means for operating said anchoring means; first lock means on said mandrels for locking said anchoring means in said operative position; seal means on said mandrels; second operator means on said mandrels operable in response to fluid pressure in one of said passageways for moving said seal means to a position of sealing engagement with the internal surfaces of a well; second conduit means on said mandrels communieating said one of said passageways with said second operator means for conducting fluid pressure from said passageway to said second operator means for actuating the same; and second lock means on said mandrels for locking said sealing means in said sealing position.

11. A well packer for use with a plurality of tubing strings in a well comprising: a plurality of mandrels, each having a passageway extending therethrough; upper and lower bodymernbers spaced longitudinally from each other and connecting the upper and lower ends respectively of said mandrels, said body members having passageways ltherein receiving said mandrels; means for con meeting each said mandrel to a diflerent one of said tubing strings wherein the passageway of each mandrel is in fluid communication with the bore of the tubing string to which it is attached; anchoring means on said mandrels movable on said mandrels betwen a retracted position and an operative position wherein said anchoring means is engageable with the internal surfaces of a well casing to hold the mandrels against movement relative to said casing; first operator means on said mandrels operable in response to fluid pressure in one of said passageways for moving said anchoring means to said operative position; first conduit means communicating said one of said passageways with said first operator means for conducting fluid pressure from said passageway to said first operator means for actuating the same to move the anchoring means to operative position; first lock means on said mandrels for locking said anchoring means in said operative position; seal means on said mandrels; second operator means on said mandrels operable in response to fluid pressure in one of said tubing strings for moving said seal means to a position of sealing engagement with a well casing; second conduit means on said mandrels id communicating said one of said mandrels with said second operator means for conducting fluid pressure from said one of said mandrels to said second operator means for actuating the same to move said seal means to sealing position; and second lock means on said mandrels for locking said sealing means in said sealing position.

12. A well packer for use with a plurality of tubing strings in a well comprising: a plurality of mandrels, each having a passageway extending therethrough; upper and lower body members spaced longitudinally from each other and connecting the upper and lower ends respectively of said mandrels, said body members having passageways therein receiving said mandrels; means for connecting each said mandrel to a diflerent one of said tubing strings wherein the passageway of each mandrel is in fluid communication with the bore of the tubing string to which it is attached; anchoring means on said man'- drels movable on said mandrels between a retracted position and an operative position wherein said anchoring means is engageable with the internal surfaces of a well casing to hold the mandrels against movement relative to said casing; first operator means on said mandrels operable in response to fluid pressure in one of said passageways for moving said anchoring means to said operative position; first conduit means on said mandrels communicating said first operator means with said one of said passageways for conducting fluid. pressure from said passageway to said first operator means for actuating the same to move said anchoring means to operative position; first lock means on said mandrels for locking said anchoring means in said operative: position; seal means on said mandrels; second operator means on said mandrels operable in response to fluid pressure in one of said tubing strings for moving said seal means to a position of sealing engagement with a well casing; second conduit means on said mandrels communicating said second operator means with said one of said tubing strings for conducting fluid pressure from said one of said tubing strings to said second operator means for actuating the same to move said seal means to sealing position; second lock means on said mandrels for locking said sealing means in said sealing position; and means on said mandrels movable by one of said tubing strings for moving said anchoring means to retracted; position.

13. A well packer for use with a plurality of tubing strings in a well comprising: a plurality of mandrels, each having a passageway extending therethrough; upper and lower body members spaced longitudinally from each other and connecting the upper and lower ends respectively of said mandrels, said body members having passageways therein receiving said mandrels; means for connecting each said mandrel to a different one of said tubing strings wherein the passageway of each mandrel is in fluid communication with the bore of the tubing string to which it is attached; anchoring means on said mandrels movable between retracted position wherein the anchoring means is adjacent the mandrels and expanded position wherein said anchoring means is remote from the mandrels and engageable with the internal surfaces of a well to hold the mandrels against movement relative thereto; first means on said mandrels operable in response to fluid pressure in one of said mandrels for moving said anchoring means to said expanded position; first conduit means on said mandrels communicating said one of said mandrels with said first fluid pressure responsive means for conducting said fluid pressure from said one mandrel to said first means for moving said anchoring means to expanded position; first lock means on said mandrels for locking said anchoring means in said expanded position; expansible seal means disposed on said mandrels adjacent said anchoring means, said anchoring means limiting movernent of said seal means on said mandrels; second means on said mandrels operable in response to fluid pressure in one of said tubing strings for moving said seal means into a position of sealing engagement with the internal surfaces of a well by compressing said seal means against said anchoring means; second conduit means on said mandrels communicating said one of said mandrels with said second fluid pressure responsive means for conducting fluid pressure from said one mandrel to said second fluid pressure responsive means for actuating said second means to move said sealing means to scaling position; and second lock means on said mandrels for locking said seal means in said sealing position.

14. A well packer for use with a plurality of tubing strings in a well comprising: a plurality of mandrels, each having a passageway extending therethrough; upper and lower body members spaced longitudinally from each other and connecting the upper and lower ends respectively of said mandrels, said body members having passageways therein receiving said mandrels; means for connecting each said mandrel to a different one of said tubing strings wherein the passageway of each mandrel is in fluid communication with the bore of the tubing string to which it is attached; anchoring means on said mandrels movable between retracted position wherein the anchoring means is adjacent the mandrels and expanded position wherein said anchoring means is remote from the mandrels and engageable with the internal surfaces of a well to hold the mandrels against movement relative thereto; first pressure responsive operating means on said mandrels operable in response to fluid pressure in one of said tubing strings for moving said anchoring means to said expanded position; first conduit means on said mandrels communicating said one of said tubing strings with said first pressure responsive operating means for conducting fluid pressure from said one of said tubing strings to said first pressure responsive operating means for moving said anchoring means to expanded position; first lock means on said mandrels for locking said anchoring means in said expanded position; expansible seal means disposed on said mandrels adjacent said anchoring means, said anchoring means limiting movement of said seal means on said mandrels; second fluid pressure responsive operating means on said mandrels operable in response to fluid pressure in one of said tubing strings for moving said seal means into a position of sealing engagement with the internal surfaces of a well by compressing said seal means against said anchoring means; second conduit means on said mandrels communicating said one of said tubing strings with said second pressure responsive operating means for conducting fluid pressure from said one of said tubing strings to said second operating means for actuating the same to move said sealing means into sealing position; second lock means on said mandrels for locking said seal means in said sealing position; and means on said mandrels movable by one of said tubing strings for retracting said anchoring means and moving said seal means from sealing engagement with said internal surfaces.

. 15. A well packer for use with a plurality of tubing strings in a well having well casing comprising: a plurality of mandrels, each having a bore extending there-.

through; upper and lower body members spaced longitudinally from each other and connecting the upper and lower ends respectively of said mandrels, said body members having passageways therein receiving said mandrels; means for connecting each said mandrel to a different one of said tubing strings wherein the passageway of each 4 mandrel is in fluid communication with the bore of the tubing string to which it is attached; anchoring rneans on said mandrels movable relative to said mandrels between a retracted position and an operative position wherein said anchoring means is engageable with the internal surfaces of said Well to hold the mandrels against movement relative to the internal surfaces of said well; first piston means on said mandrels operable in response to a first lower fluid pressure in one of said passageways for moving said anchoring means to said operative position; first conduit means communicating said one of said passageways with said first piston means for conducting fluid pressure from said passageway to said piston means for actuating the same to move said anchoring means to operative position; first lock means on said mandrels for locking said anchoring means in said operative position; seal means on said mandrels adjacent said anchoring means, said anchoring means limting movement of said seal means on said mandrels; second position means on said mandrels operable in response to a second higher fluid pressure in one of said passageways for moving said seal means into a position of sealing engagement with the internal surfaces of said well by compressing said seal means against said anchoring means; second conduit means on said mandrels communicating said one of said passageways with said second piston means for conducting fluid pressure from said passageway to said second piston means for actuating the same to move said seal means to sealing position; second lock means on said mandrels for locking said seal means in said sealing position; and means on said mandrels responsive to rotary and upward movement of one of said tubing strings for retracting said anchoring means and moving said seal means from sealing engagement with said internal well surfaces.

References Cited in the file of this patent UNITED STATES PATENTS 2,903,066 Brown Sept. 8, 1959 2,972,379 Brown Feb. 21, 1961 2,991,833 Brown et al. July 11, 1961 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,167 127 January 26, 1965 Phillip S. Sizer It is hereby certified that error appears in the above numbered pat- 'ent requiring correction and that the said Letters Patent should read as corrected below.

Column 16, line 30, for "limting" read limiting"; line 31, for "position" read piston Signed and sealed this 29th day of June 1965.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attosting Officer Commissioner of Patents

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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3275079 *Jan 23, 1963Sep 27, 1966Dresser IndDual string hydraulic packer
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US3361211 *Feb 10, 1966Jan 2, 1968Joe R. BrownDual production well packer
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Classifications
U.S. Classification166/120, 166/189, 166/187
International ClassificationF16L39/00, E21B33/122, E21B33/12
Cooperative ClassificationF16L39/00, E21B33/122
European ClassificationF16L39/00, E21B33/122