US3460618A

US3460618A - Thru-tubing bridge plug

Info

Publication number: US3460618A
Application number: US630864A
Authority: US
Inventors: Leon Blagg
Original assignee: Schlumberger Technology Corp
Current assignee: Schlumberger Technology Corp
Priority date: 1967-04-14
Filing date: 1967-04-14
Publication date: 1969-08-12
Anticipated expiration: 1986-08-12

Description

Aug. l2, 1969 L.. BLAGG THRU-TUBING BRIDGE PLUG 2 Sheets-Sheet l Filed April 14, 1967 Aug. l2, 1969 l.. BLAGG THRU-TUBING BRIDGE PLUG 2 Sheets-Sheet 2 NVENTOR Filed April 14, 1967 JTI'ORNE Y United States Patent O1 ice 3,460,618 Patented Aug. 12, 1969 3,460,618 THRU-TUBING BRIDGE PLUG Leon Blagg, Channelview, Tex., assgnor to Schlumberger Technology Corporation, Houston, Tex., a corporation of Texas Filed Apr. 14, 1967, Ser. No. 630,864 Int. Cl. E21b 23/00, 33/134 U.S. Cl. 166-184 17 Claims ABSTRACT F THE DISCLOSURE Apparatus for plugging a well conduit below open tubing, including a support tube having an inflatable packer element mounted thereon. A vent passageway extends between locations above and below the packer element. A remotely controllable pump structure is releasably coupled to the support tube and is adapted, when operated, to

displace a cementitious medium into the packer element to This invention relates generally to well tools and more particularly to a packer or plug which can be lowered in a well through tubing and then set to pack off a well conduit, either cased or open hole, below the lower end of the tubing.

Prior art tools of this type, that is, so called thru-tubing packers or plugs, have not been particularly effective in providing a pressure bridge which will prevent fluid flow in the well conduit. Such tools have generally included an expansible packer element which can be inflated by a cementitious medium under pressure. The packer element provides a bridge or platform in the well bore on which more cementitious medium can be deposited and then the medium both within the packer element and on top of it are permitted to harden to form an elongated l solid plug.

Some of the difficulties have arisen due to the fact that there is a waiting time involved to permit the cementitious medium to set up or harden, and the plug has been susceptible to disturbance by well fluids which may be produced into the well bore during this time. That is to say, the production of fluid can cause a pressure differential to be developed across the plug before the cementitious medium hardens which tends to force fluids past the plug. If this occurs, the flow will cause channels around the packing element and the medium on top thereof which provide communication paths through the plug. Such channels will destroy the plugs effectiveness in holding pressure and render the plug useless for its intended purpose.

Accordingly, it is an object of the present invention to provide a new and improved well tool of the type described which will effectively pack off a well bore.

Another object of the present invention is to provide a new and improved well tool of the type described which is arranged so that no appreciable pressure differentials can be developed across the plug while it is being formed, thereby eliminating the channeling problems of the prior art.

Yet another object of the present invention is to provide a new and improved well tool of the type described which is simple and reliable in operation and inexpensive to manufacture.

These and other objects are attained in accordance with the concepts of the present invention by providing a support tube having an inflatable packer member mounted thereon which is adapted for a wide range of expansion upon inflation. The support tube has inflation and vent passages formed therein, the vent passage extending between locations above and below the packer element, and the inflation passage opening into the interior of the packer member.

A remotely controllable pump device is releasably coupled to the support tube and is arranged to displace an inflating medium into the packer element through the inflation passageway. When desired, the pump device can be dislconnected from the support tube for retrieval from the we l.

A vent valve is adapted to selectively close off the vent passageway and can be automatically operated upon disconnection of the pump device. Moreover, the present invention is arranged so that cementitious medium can be deposited on top of the inflated packing element to form a lengthy and effective plug in the well bore prior to closing off the vent valve.

The present invention has other objects and advantages which will become apparent in connection with the following detailed description. The novel features of the present invention being set forth with particularity in the appended claims. The organization. and operation of the present invention can best be understood by way of illustration and example of a preferred embodiment thereof when taken in conjunction with the drawings in which:

FIGURE 1 is a longitudinal sectional View showing somewhat schematically the various parts of the present invention in relative positions for lowering into a Well conduit through a tubing string;

FIGURE 2 is a sectional view showing schematically the present invention set in a Well conduit and the vent passageway open;

FIGURE 3 is a View similar to FIGURE 2 but with additional medium deposited on the packer element and with the pump section disconnected and the vent passageway closed off;

FIGURE 4 is an enlarged sectional view of the control section of the present invention; and

FIGURE 5 is an enlarged sectional view of the inflation valve section of the Present invention.

Generally speaking, the tool is shown in FIGURE l to consist basically `of a control section A, a pump and bailer section B, a valve section C and a packer section D. The packer section D includes an inflatable, expansible packer element 10 mounted around a central support tube 11, the packer element 10 being adapted for a wide range of expansion upon inflation. A vent passageway 12 extends through the support tube 11 between locations above and below the packer element 10 and is n-ormally open so that fluid can pass through the packer element whether it is expanded or not. A valve element 13 is provided for selectively closing the vent passageway 12 as will be further described.

The valve section C includes a valve member 14 which normally closes off an inflation passageway 15 which opens into the interior of the packer element 10. As will be further described, the valve member 14 can be moved to an open position so that an inflating medium 16 contained within a chamber 17 can be displaced through the inflation passageway 15 and into the packer element 10 to inflate the packer element. Upon inflation, the packer element 10 can function to bridge or plug a well conduit. The fluent medium 16 can 'be a cementitious substance or a plastic which has liquid properties for a length of time and which will eventually set up or harden into a solidified mass.

The pump section B is arranged to displace the fluent medium 16 into the interior of Ithe packer element 10 and includes a weighted member 18 which is capable of performing this function. The weighted member 18 is initially restrained from assuming a working condition by a latch mechanism 20. The latch mechanism 20 is arranged to be operated by a control section A which can be remotely controlled from the earths surface by electrical signals transmitted through an armored electrical cable 21. The cable 21 provides a suspension member on which the entire tool can be lowered into a well.

Having generally described the various parts of the present invention, atten-tion is directed to FIGURES l and 4 for further structural detail. The control section A includes a tubular case 25 having a longitudinally extending chamber 26 therein. A piston 27 is sealingly and slidably received within the chamber 26 and a rod 28 connected to the piston extends downwardly through a bore 29 which opens axially into the chamber 26. The upper portion 38 of the chamber 26 is arranged to receive a suitable hydraulic uid, and a compressed coil spring 31 is arranged in the lower portion 32 of the chamber -to urge the piston 27 and the rod 28 upwardly. Several side ports 33 in the wall of the case 25 below the piston 27 enable fluid pressures within the upper chamber portion 26 to be balanced with hydrostatic well fluid pressures as the tool is lowered into a uid filled well bore. A typical one-way check valve 35 is positioned within an entry passage 36 to permit filling the upper chamber portion 30 with a suitable hydraulic fluid. A uid discharge passageway 37 extends upwardly from the chamber portion 30 and is continued by an axial passageway 37 formed in a valve seat sub 39. A remotely controllable valve 38, such as a conventional solenoid operated valve, is arranged to cooperate with the sub 39 to normally prevent discharge of the hydraulic fluid from the chamber portion 3] so that the piston 27 and the rod 28 cannot move upwardly under the influence of the force being exerted by the coil spring 31. However, opening of the valve 38 will permit uid in the chamber portion 30 to discharge to the well annulus via the

passages

37 and 37 and a port 37 shown in FIG- URE 4 in .dashed lines for convenience of illustration.

The piston rod 28 extends downwardly through the bore 29 to a location within a recess 40 where it can operate the latch mechanism 20. The latch mechanism 20 includes a plurality of upwardly extending latch fingers 41, the latch fingers terminating in enlarged head portions 42. When the parts are in the relative position shown in FIGURE 4, the head portions 42 are held outwardly by the rod 28 in engagement with an inclined shoulder 43 formed by the recess 40. However, it will be appreciated that removal of the rod 28 from behind the head portions 42 will permit them to cam inwardly and out of engagement with the shoulder 43. The retention and release of the fingers 41 from the recess 40 controls the operation of the pump and bailer section B.

The pump and bailer section B includes a cylindrical housing 45 coupled at its upper end to the control section A and at its lower end to a bailer cylinder 46. The housing 45 has a bore 47 in which the Weighted member 18 is stationed. The weighted member 18 can be an elongate tubular member formed with a rod 48 extending upwardly from its upper end, the rod having the previously described latch fingers 41 connected to its upper end and extending into the recess 40. A compressed coil spring 49 can surround the rod 48 with its upper end pressing against a surface 50 at the upper end of the bore 47 and its lower end pressing against the upper surface of the weighted member 18. The coil spring 49 exerts downward force on the weighted member 18 which is retained, however, by the rod 48 and the engaging relation of the latch fingers 41 with the latch recess 40.

Positioned within the bore of the bailer cylinder 46 and spaced downwardly and away from the lower end of the weighted member 18 is a cylindrical piston member 51 having an elastomer swab cup 52 suitably connected to its lower end. The swab cup 52 defines the upper end 4 of the chamber 17 which is adapted to confine the inllating medium 16 as previously described. Of course, the chamber 17 is appropriately sized so as to contain a predetermined volume of the medium as will be apparent to those skilled in the art. The lower end of the chamber 17 is closed by a section 53 having a reduced diameter outer surface 54 which is sized for telescopic reception into a bore 55 formed in the valve assembly C. An offset bore 56 opens the lower end of the chamber 18 and a shearable pin member 58 releasably couples the bailer cylinder 46 to the valve assembly C for purposes which will be hereinafter described.

Referring to FIGURES l and 5 for details of the valve assembly C, a valve housing 60 can include upper and lower tubular members 61 and 62 threadedly coupled together, the lower member 62 having a central chamber formed therein with stepped wall surfaces providing a rst larger chamber portion 64 and a second smaller chamber portion 65. The valve element 14 can take the form of a sleeve piston and is slidably received within -the chamber 63, the sleeve piston having an enlarged head 67 received in the larger chamber portion 64 and a tubular portion 68 extending downwardly into the smaller chamber portion 66. An O-ring 69 seals between the head portion 67 and the wall of the larger chamber portion 64, and a second O-ring seal 70 can be positioned in a groove around the tubular portion 68. A counterbore 71 serves to space a length of lower chamber wall away from the seal 70 and a side port 72 through the wall of the housing 60 communicates with the counterbore. Moreover, several ports 73 can extend through the wall of the tubular portion 68. In this manner, fluid pressures within the various portions of the chamber 63 can equalize with uid pressures in the well annulus as the 4tool is shifted within a fluid lled well bore and it will be appreciated that the various parts of the valve assembly C and the packer section D will not be subjected to any possibly damaging pressure differentials.

The valve element 14 further has a central bore 75 extending therethrough which is sized to sealingly receive a tubular member 76 which extends downwardly from the upper housing member 61. The tubular member 76 is, in turn, sealingly coupled to the upper end portion of a smaller diameter vent tube 77. The respective bores of the vent tube 77 and the tubular member 76 forfm the upper end of the vent passageway 12 which is opened to the exterior of the tool by a side port 78. The upper valve housing member 61 further has an axially extending offset bore 79 which is aligned with the bore 56 in the lower end section 53 of the bailer cylinder 46. An appropriate face seal 80 is positioned at the juncture of the two

bores

79 and 56 to prevent any leakage of the inflating medium 16 to the outside of the tool.

It will Ibe appreciated that the valve element 14 is arranged to prevent flow of the inflating medium 16 from the bailer cylinder 46 as long as the valve element is in its upper position as shown in FIGURE 5. The valve element 14 is retained in this position by a shear screw 81 which can extend through the wall of the lower housing member 62 and into a recess 82 in the valve element. A compressed coil spring 83 is arranged within the upper chamber portion 64 to exert downward force on the valve element 14 for moving it to a lower or open position when the shear screw 81 fails. When the valve element 14 moves downwardly within the chamber 63, its head portion 67 can telescope away from the tubular extension 76 to place the oifset bore 79 in communication with the annulus 84 between the valve element 14 and the vent tube 77, thereby -permitting the inflating medium within the chamber 17 to pass downwardly through the valve element.

Referring again to FIGURE 1, the packer section D includes the tubular body or support 11 which can tbe integrally formed with, and extend downwardly from, the valve assembly C, the lowermost end of the support tube being provided with a rubber bumper sub 85 for insulating the tool from shock loads which may be encountered during lowering. The packer element is mounted around the support tube 11 with its lower end portion secured by a clamp device 86 to a lower sleeve 87 which is slidably arranged on the support tube. The upper end of the packer element 10 is similarly secured to an upper sleeve 88. Suitable seals 489 and 90 fluidly seal between the sleeves and the support tube 11 to prevent fluid leakage. An annular passageway 91 extends in the upper portion of the support tube 11 and communicates with the interior of the packer element 10 via several lateral ports 92, the upper end of the passageway being rcoextensive with the annulus 84 between the valve element 14 and the vent tube 77. Accordingly, inating medium which passes through the valve element 14 can enter into the interior of the 'bag to expand it outwardly and against a surrounding well conduit wall. The packer element 10 can be constructed of a suitable cloth such as Dacron which is impregnated with neoprene so as to be readily pliable as well as substantially impermeable. The packer element can have longitudinal or spiral folds (not shown) therein to reduce its diameter and permit it to be expanded to a size which is several times its folded size. The entire tool can have a small outer diameter such as 1%6" for passing through small tubing, yet be capable of plugging a relatively large size conduit such as 51/2 or 7".

Although the upper sleeve 88 is sized to slide on the support tube 11, it is initially restrained against sliding motion as shown in FIGURE 5 -by locating the inner portion of a seal element 93 within a peripheral groove 94 around the support tube =11 so that the seal element itself can yieldably resist relative motion between the sleeve and the support. In this manner, the lower sleeve 87 will slide upwardly along the support tube 11 as the packer element 10 is inflated to accommodate change in vertical length while the upper sleeve 88 will temporarily remain stationary on the support tube 11.

Referring again to FIGURE 1, the vent passageway 12 extends axially through the support tube 11 to a chamber 95 at the lower end portion of the support tube, the chamber 95 being normally open to the well bore by several side ports 96. The vent valve 13 can take the form of a sleeve which is movable within the chamber 95 between a lower position where the side ports 96 are open, and an upper position where

seal elements

97 and 98 can liuidly seal against the wall surface of the chamber above and below the side ports 96. In the upper position, the valve 13 functions to close olf the side ports 96 and thus the vent passageway 12. It will be appreciated that the

seal elements

97 and 98 on the valve element 14 are arranged to encompass substantially the same areas so that the valve element is pressure balanced in both the open and closed positions and will not move in response to pressure from above or below.

For moving the vent valve 13 between its lower and upper positions, a valve actuating wire 99 can tbe suitably connected to the vent valve by a coupling 100, the wire 99 extending upwardly through the vent passageway 12 and into a recess 101 located within the lower section 53 of the bailer cylinder 46 as shown in FIGURE 5. The upper end of the wire 99 can be securely attached within the recess 101 by any suitable means such as threaded set screws 102 extending through the wall of the lower section 53. It will be appreciated that an upward pull on the wire 99 can cause upward shifting of the vent valve 13 to its upper position for closing the -vent passageway 12 to fluid flow.

Operation In operation, the tool is prepared for lowering into the well by filling the chamber portion 30 above the release piston 27 with a suitable hydraulic fluid so that the rod 28 is properly positioned for coaction with the latch fingers 41. The weighted member 18 is then latched in its inactive position as shown in FIGURE 1. The coilspring 49 which is engaging the weighted member 18 is in compressed condition and exerts downward force on the weighted member. The inflation valve member 14 is secured in its upper or closed position by the shear screw 81 and the bailer chamber 17 can. be lled with a predetermined volume of inflating medium 16y of the type heretofore described. The vent valve actuating wire 99 is appropriately secured to the bailer cylinder 46 as previously described so that the vent valve 13 is in a lower position where the side ports 91 are open.

The tool can then be lowered downwardly into a well on the cable 21 through the tubing T and to a selected setting lpoint within the well conduit P below the lowermost end of the tubing as shown in FIGURE 2. If desired, the tool can be positioned so that the packer section D is positioned immediately below a collar joint in the casing P. At setting depth, an electrical signal initiated at the earths surface and conducted through the cable 21 will open the solenoid operated valve 38 in the control section A so that the hydraulic lluid can be forced to exit from the chamber portion 30 by the spring 31 acting upwardly on the piston 27. As the uid exits, the piston 27 and the rod 28 will move upwardly, thereby moving the lower portion of the rod 28 from behind the latch lingers 41. The head portions 42 will then shift inwardly and release from the recess 40.

When the latch mechanism 20 is released, the force of the spring 49, which is initially compressed, acts to accelerate the weighted member 18 downwardly so that it can strike the piston 51 with jarring force. This coaction creates a substantial pressure surge in the medium 1'6 within the bailer chamber 17 which acts upon the upper face of lthe valve element 14, thereby exerting a substantial force on the valve element to shear off the valve retaining screw 81. Release of the retaining screw `81 permits the valve element 14 to move downwardly under the influence of the spring 83 to an open position shown in FIGURE 2. In this position, the seal element 70 seals against the wall of the lower chamber 65 to close oil the

pressure balancing ports

72 and 73. The fluent me-dium can pass through the annulus 84, the inflation passageway 91 and through the side ports 92 and into the interior of the bag 10 to inllate it.

The weighted member 18, after striking the piston 51 to open the valve element v14, will rest on the piston 51 and tend to gravitate downwardly. Downward gravitation of the weighted member 18 will generate pressure within the chamber 17 and thereby displace the medium 16 into the interior of the bag 10 to inflate it. As the bag 10 inflates, the lower sleeve 87 can slide upwardly along the support tube 11 to accommodate changes in vertical length of the bag. However, the upper sleeve 88 is restrained from sliding during inflation as previously described.

It will be appreciated that inflation pressure which can be built-up in the bag 10 is a function of the weight of the weighted member 18 and the cross-sectional area of the swab cup 52. The weighted member 18 can be constructed of suitable heavy or dense metal such as tungsten and be sized relative to the area of the swab cup 52 so that a suitable inflation pressure, for example, 15-25 p.s.i., can be developed within the bag 10 to expand it into effective sealing engagement with the well conduit wall as shown in FIGURE 2.

After the bag 10 is fully inflated, an upward pull on the cable 21 is utilized to shift the support tube 11 upwardly relative to the packer member 10, thus exposing the inflation ports 92 to the well annulus above the packer as shown in FIGURE 3. Of course during upward movement, the upper sleeve seal ring 93 is displaced from the support tube groove 94. Movement of the inflation ports 92 above the seal ring 93 will trap the inflation pressure within the expanded packer 10 to maintain its expanded condition. Exposure of the ports 92 above the sleeve 88 permits dumping a remaining volume of medium within the bailer cylinder 46 on the top side of the packer 10 to increase the overall length of plug formed in the well conduit. The packer 10, in expanded condition, forms a platform or bridge in the well conduit for supporting the medium thereabove. If the packer section D is positioned immediately below the collar joint 105, it will be appreciate-d that part of the medium 16 can iiow into the annular recess formed by the joint. With the tool parts in their relative positions shown, a sufficient period of time is allowed to pass so that the medium both within the packer 10 and on its top side can harden into a solidied mass.

During the time that the medium is hardening, the vent passageway 12 remains open so that any produced Huid entering the casing P from below the packer 10 can pass upwardly therethrough and enter the well annulus above the packer through the side vent port 78. Accordingly, it will be appreciated that such liuids will have no tendency to form channels either around the packer element 10 or through the medium on top of the packer element, which distur-bances may other-wise destroy the effectiveness ofthe plug in holding pressure.

When the plug is fully formed, an upward pull on the cable 21 will serve to shear the releasing pin 58 to disconnect the pump section C from the packer section D. Of course, the packer section D will not move upwardly because of the holding force of the packer element 10 and medium 16 on top of the packer element against the well casing. After release, the pump and control sections B and A can be hoisted upwardly through the tubing T and retrieved from the well. The initial upward movement of the pump section C imparts upward movement 'to the valve actuating wire 99 which, in turn, moves the vent valve 13 to its upper closed position. When the vent valve 13 engages the top end of the chamber 95, `tension in the wire 99 due to continued upward movement of the pump section C will cause the wire to break or part as shown in FIGURE 3 and the vent valve 13 is left in a closed position to block fluid movement within the vent passageway 12. Accordingly, the structure remaining in the well casing packs off the entire cross section of the well bore and is capable of withstanding substantial pressures which may be imposed upon it.

If desired, further cementitious material can be deposited within the well conduit on top of the plug already formed to further increase the overall length of same. This can be accomplished using a conventional clump bailer. Moreover, it will be noted that the control, pump and valve sections A, B and C of the present invention are well suited for service as a dump bailer with the valve housing portion A62 modified to have only a lower nose portion (not shown) -with a central axial port.

A new and improved apparatus has been disclosed for effectively plugging a well conduit. According to the present invention, the plug can be `formed in a large size conduit without removal of a smaller tubing from the well, and the invention is arranged in a manner to prevent disturbance of the plug by fluid ow while it is being formed so that the plug will be effective in preventing fluid flow in either direction past its setting point.

Since certain changes and moditications may be made in the disclosed embodiment of the present invention without departing from the concepts involved, it is the aim of the appended claims to cover all such changes and modications which fall within the true spirit and scope of the present invention.

I claim:

1. A well packer apparatus comprising: a support tube; an inatable expansible packer member mounted around said support tube and adapted for a wide range of expansion upon inflation; a vent passage extending in said support tube between locations above and below said packer member; an inflation passageway extending in said support tube and opening into said packer member; pump means releasably coupled to said support tube including a chamber means adapted to contain an initially uent material capable of subsequent hardening, said pump means adapted for displacing the iiuent material through said intiation passageway to intiate said packer member; means for releasably connecting said pump means to said support tube; normally open valve means in said vent passageway for selectively closing off same; and valve closing means actuated by release of said pump means from said support tube for closing said vent passageway.

2. The apparatus of claim 1 wherein said pump means includes a piston member in said chamber, and means for moving said piston member in said chamber to displace the iiuent material from said chamber.

3. The apparatus of claim 2 wherein said moving means comprises a weighted member; means for retaining said weighted member in an inactive position; and control means remotely operable from the earths surface for releasing said retaining means so that said weighted member can assume an active position for moving said piston member.

4. The apparatus of claim 1 further including normally closed valve means in said inflation passageway; and means for opening said valve means in response to actuation of said pump means.

5. The apparatus of claim 3 further including normally closed valve means in said intiation passageway; and means for opening said valve means in response to movement of said weighted member to said active position.

6. A well packer apparatus comprising: a support tube; an iniiatable packer bag mounted around said support tube and adapted for a wide range of expansion upon inflation; chamber means connected to said support tube in fluid communication with the inside of said packer bag, said chamber means arranged to contain a fluent medium; means for applying pressure to the fluent medium to inflate said bag including a piston member and a weighted body capable of applying force to said piston member; remotely operable means for controlling the operation of said weighted body and said piston member; a fluid passageway extending through said packer bag and arranged to provide a fluid ow path between locations in communication with the well bore above and below said packer bag, said passageway at one of said locations terminating in a laterally extending port; and valve means movable on said support tube between longitudinally spaced positions, said valve means in one of said positions closing oft said port to prevent tiuid ow through said passageway.

7. The apparatus of claim 6 further including releasable means for coupling said chamber means to said support tube.

S. The apparatus of claim 7 further including an actuator extending in said passageway for moving said valve means between said spaced positions.

9. The apparatus of claim 6 wherein said valve means includes a sleeve member having an opening throughout its length whereby fluid pressure, when said sleeve member is in position closing said port, can act with equal force in opposite longitudinal directions on said sleeve member thereby precluding movement of said sleeve member responsive to said fluid pressure.

10. The apparatus of claim 6 further including another valve means between said chamber means and said packer bag; and releasable means for retaining said other valve means in a normally closed condition, said retaining means being releasable upon the application of pressure to said uent medium to permit said other valve means to assume an open condition.

11. A Well packer apparatus comprising: packing means for closing oli the cross section of a well bore, said packing means including an intiatable bag; chamber means releasably coupled to said packer means and arranged to contain a cementitious inflating medium; inflation passage means extending from said chamber means to an intiation port opening to the inside of said bag; means for generating pressure within said chamber means to force said medium into said bag to inflate it; a vent passageway extending between locations above and below said packing means for initially preventing the development of a pressure differential across said packing means to allow said medium to harden without disturbance, said passageway including a vertically extending portion and a side port; and pressure balanced valve means including a sleeve member movable in said vertically extending portion to a position spanning said side port and closing off said vent passageway.

12. The apparatus of claim 11 wherein said packing means further includes a central support; means sealingly and slidably coupling the ends of said bag to said support whereby said support can be moved longitudinally relative to said bag; said ination port, after inflation of said bag, being disposable by longitudinal relative movement between said support and bag in a position above said bag whereby cementitious medium in said chamber means can be deposited on top of said bag.

13. The apparatus of claim 12 wherein said vent passageway extends to a location above the cementitious medium which is deposited on top of said bag.

14. A well packer apparatus comprising: an elongated support tube; an inflatable packing element mounted around said support tube; means for sealingly and slidably connecting the ends of said packing element to said support tube, whereby said support tube can be moved vertically relative to said packing element when said packing element is inllated; an ination passageway extending in said support tube and terminating in port means -initially in communication with the inside of said packing element and through which a cementitious medium under pressure can be displaced for inflating said packing element, said support tube, after inflation of said packing element, being adapted for said vertical movement to a position relative to said packing means whereby said port means is exposed to the Well annulus on one side of said packing means and cementitious medium can be deposited via said port means in the well annulus on said one side.

15. The well apparatus of claim 14 further including a vent passageway in said support tube extending between locations above and below said packing element and through which well uids can flow while said packing element is expanded; and valve means for selectively closing off said vent passageway.

16. The well apparatus of claim 15 wherein said vent passageway terminates at one end in lateral port means in said support tube, said valve means including a sleeve member arranged to close off said lateral ports, said sleeve member being pressure balanced so as to be immovably responsive to fluid pressures.

17. A device for use in a well comprising: an elongated housing having a chamber therein adapted to contain a uent medium, the lower end of said housing having an opening, the upper end of said housing being adapted for connection to a lowering member; a uid displacing piston in said housing at the upper end of said chamber; means for actuating said piston located in said housing above said piston including a Weighted body and suspension means for stationing said body above and in vertically spaced apart relation to said piston; remotely operable means for releasing said suspension means whereby said weighted body can fall into engagement with said piston and, due to force developed by impact of said weighted body on said piston, generate a pressure surge in said medium; and normally closed valve means in said opening, said valve means being opened in response to the generation of said pressure surge in said medium to enable iluent medium to be displaced from said chamber via said opening.

References Cited UNITED STATES PATENTS 2,222,750 ll/ 1940 Litolff 166-187 2,618,344 l1/l952 Turechek et al. 166-187 2,629,446 2/1953 Freling et al 166-187 2,717,644 9/1955 Bell et al. 166-187 2,769.498 11/1956 Huber 166-187 2,978029 4/ 1961 OReilly et al. 166 187 JAMES A. LEPPJNK, Primary Examiner U.S. Cl. XR.. l66-187, 31S