US3156300A

US3156300A - Method and apparatus for protecting wells

Info

Publication number: US3156300A
Application number: US302073A
Authority: US
Inventors: John S Page; Jr John S Page
Original assignee: Individual
Current assignee: Individual
Priority date: 1963-08-14
Filing date: 1963-08-14
Publication date: 1964-11-10
Anticipated expiration: 1981-11-10

Description

Nov. 10, 1964 J. 5. PAGE ETAL METHOD AND APPARATUS FOR PROTECTING WELLS 5 Sheets-Sheet 1 Filed Aug. 14, 1963 INVENTORS. 170/4 6. 1246s, trap/1v 5. PAGE, rTe.

B I I ATTORNEX 5 Sheets-Sheet 3 Nov. 10, 1964 J. 5. PAGE ETAL METHOD AND APPARATUS FOR PROTECTING WELLS Filed Aug. 14, 1963 1 10. 4

x w i i J TA)- mi m r I ,l 5. a 1 5% & \i g I o N mmlg m J? a W A \w\\ \T A B a .4. i Z w a I 5 F f 5 Sheets-Sheet 4 Nov. 10, 1964 J. 5. PAGE ETAL METHOD AND APPARATUS FOR PROTECTING WELLS Filed Aug. 14, 1965 We. iii-F Wm q 2 a W a w u m m M J J J J J 0 4 7.9 16? 3 7 m 020 s w a $3 H Z 0; n n \W w h/Q-m? I I I F 5 2 M 0 4 5 5 a 5 a 2 a u a 9 J y m J 1 B1 A B1 Nov. 10, 1964 J. 5. PAGE ETAL 3,156,300

METHOD AND APPARATUS FOR PROTECTING WELLS Filed Aug. 14, 1965 Sheets-Sheet 5 M 1 ir 116.9. 6.10.

v we {02 .106

. I J09 .146 Z- 121 4 111 P .166 166 J54 INVENTORS.

276/4 5. P465, rIHN 5. R465, rI.

ATTORNEY- United States Patent 3,156,300 METHOD AND APPARATUS FGR PROTECTHNG WELLS John S. Page and John S. Page, Jr., both of 1450 El Mirador Ave, Long Beach, Calif. Filed Aug. 14, 1963, Ser. No. 302,073 29 Claims. (Cl. 166-665) This application is a continuation-in-part of our copending application Serial No. 450,884, filed August 19, 1954, now abandoned.

This invention relates to the protection of producing wells, particularly oil wells situated in bodies of water, to prevent loss of the products of such wells in event the upper portions thereof are subjected to damaging forces.

In wells located in the waters of gulfs, lakes and oceans, the platforms above the surface of the Water and the casings between the platforms and the submerged land are vulnerable to breakage or rupture by collision with ships or other vessels, especially in stormy weather.

It is known that flowing wells located in bodies of water have suffered considerable loss of the valuable products thereof as a result of ships, barges, or floating objects colliding with the platforms and rupturing the exposed vulnerable portions of the casing or flow lines connected therewith at the top of the well.

Accordingly, it is the primary object of the present invention to provide a novel method and means for automatically shutting off the flow of a well such as described, at a safe distance below the Vulnerable parts of the well incident to the platform or other parts at the top of the well or adjacent the top of the well, being accidentally subjected to forces which are likely to rupture or will rupture the vulnerable parts.

It is another object of this invention to provide a novel method of protecting a well of the character described in a manner such that the shutting off of the flow at a safe distance below the vulnerable part of the casing and flow lines, will take place before the forces sustained thereby become effective to rupture such parts.

Another object of the invention is to provide means and a method for protecting a well for the purpose described, by utilizing valve means actuated by fluid pressure in the well to automatically shut off the flow in the well at a safe distance below the vulnerable parts at the top of the well or adjacent the top of the well, incident to these vulnerable parts sustaining a shock or impact of such severity as would tend to rupture them and consequently cause an uncontrolled flow of the well.

Another object of this invention is to provide a shut-off tool for protecting a well in the manner described, wherein valve means for shutting off the Well is actuated by the fluid pressure in the well to maintain normal production in such a manner that incident to the platform or adjacent parts of the well sustaining a collision shock or a similar shock of a severity which would rupture such vulnerable parts, the valve means will also be actuated by the fluid pressure in the well to shut off the flow at a safe distance below said vulnerable parts prior to the rupturing thereof.

It is another object hereof to provide a novel trigger means which operates the valve means to shut off the flow below the parts of the well susceptible to rupturing, incident to the initial application to the trigger means of a severe collision shock or a similar force transmitted through the well platform or associated elements at the top of the well, thereby shutting off the well before such forces become effective to rupture the casing and associated flow lines at the top of the well.

An additional object hereof is to provide a shut-off tool such as described which readily may be positioned "ice in a well on a tubing string so as to be subject to operation responsive to trigger means at the top of the well or manually controlled from the top of the Well.

A further object hereof is to provide a shut-off tool such as described which includes a retrievable valve unit arranged so that it may be detached from the tool by the application to the tool from the top of the well, of fluid pressure in excess of the normal pressure of the well, whereby the unit readily may be raised for inspection or replacement of parts as required and as readily replaced on the tool.

Another object hereof is to provide a tool such as described wherein a novel sleeve valve for controlling the flow to the top of the well is hydraulically balanced by the fluid pressure in the well during flow of the well and remains open as long as the Valve is hydraulically balanced, but will move to closed position and shut off flow at the tool responsive to fluid pressure in the well when the balancing fluid pressure on one side thereof is relieved.

It is a further object hereof to provide a tool such as described wherein trigger means at the top of the well will respond to severe collision shocks or like impacts against the platform and associated vulnerable element of the well, to vent to the atmosphere the fluid pressure causing the valve to be hydraulically balanced, whereby fluid pressure in the Well Will be effective to close the valve and shut off flow to the top of the well.

An additional object of the invention is the provision of a novel pressure relief valve which is actuated by the trigger means to vent to the atmosphere the fluid pressure balancing the shut-off valve as well as to maintain the fluid pressure in the well against the shut-off valve, whereby the latter will be moved to closed position to shut-off flow to the top of the well.

It is another object hereof to provide a shut-off tool of the character described wherein a novel hydraulically operated anchoring means is actuated to securely anchor the tool to the casing of the well incident to the venting to the atmosphere of the fluid pressure which provides for hydraulically balancing the shut-off valve.

Still another object of the invention is to provide a fluid pressure operated and controlled sub-surface shut-off valve for use in flowing wells, wherein, responsive to the application of fluid pressure to first and second surfaces of a movable valve member and under the control of means at the top of the well for controlling the application of fluid pressure to the first of said surfaces, the valve will be permitted to close.

This invention possesses many other advantages and has other objects which may be made more easily apparent from a consideration of one embodiment of the invention. For this purpose there are shown a number of forms in the drawings accompanying and forming part of the present specification. These forms will now be described in detail, illustrating the general principles of the invention, but it is to be understood that this detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

Referring to the drawings:

FIG. 1 is a schematic view of means embodying the present invention as installed on a Well situated in a body of water;

FIG. la is a cross sectional view taken on the line 1alm' of FIG. 1.

FIG. 1b is an enlarged vertical sectional view of the trigger valve at the top of the well;

FIG. 2 is a fragmentary vertical sectional view of the upper part of a retrievable shut-off tool embodying this invention, as operatively associated with the casing and tubing string of a well such as shown in FIG. 1;

FIG. 2a is a continuation view of FIG. 2, showing the lower part of the shut-off tool;

FIG. 2b is an enlarged sectional view taken on the line 2b-2b of FIG. 2a;

FIG. 3 is an enlar ed sectional view of the valve unit in the portion of the tool shown in FIG. 2 with the valve open;

FIG. 4 is a fragmentary vertical sectional view, partly in elevation, of the valve unit shown in FIG. 3, with the valve closed;

FIG. 5 is an enlarged fragmentary vertical sectional view of the valve unit as it would appear when released and ready to be retrieved;

FIG. 6 is a cross sectional view, taken on the line 6-6 of FIG. 4;

FIG. 7 is a sectional view, similar to FIG. modified form of the present invention;

FIG. 7a is a continuation view of FIG. 7, showing the lower part of the tool shown in FIG. 7;

FIG. 8 is an enlarged fragmentary view of the valve unit shown in FIG. 7, with the valve open;

FIG. 9 is an enlarged fragmentary vertical sectional view, partly in elevation, of the valve unit shown in FIG. 8, with the valve closed;

FIG. 10 is an enlarged fragmentary sectional view of the valve unit shown in FIG. 8 as released and ready to be retrieved;

FIG. 11 is a cross sectional view taken on the line 1111 of FIG. 8;

FIG. 12 is a fragmentary sectional view, partly in elevation, of a modified form of packer setting means; and

FIG. 13 is a fragmentary sectional view taken on the line 13-13 of FIG. 3.

In accordance with one embodiment of this invention, a tool mounted on a tubing string as a section thereof and including anchoring means, packing means and an especially constructed shut-off valve unit, is run into the casing of a well to be protected, for example an oil well of the flowing type situated in a body of water.

The tool is then anchored to the casing and the packing means set to form a seal between the tool and the casing whereby the tool is anchored at a point for operation, for example, 100 or more feet below the surface of the submerged land.

A pipe line connected with the valve unit in the tool is lowered with the tool into the Well casing so that fluid under pressure from the top of the well may be applied to and vented from the valve unit in a manner to be hereinafter described.

After anchoring the tool in the casing, that portion of the tubing string extending upwardly from the upper end of the tool, is removexl from the well and a tubing plug is lowered into the well to close the upper end of the tool.

The tool provides port means below the plug whereby well fluid may flow into the casing and thence to the top of the well through the casing.

The shut-off valve unit includes a normally open sleeve valve above the packing means and which is axially movable to close the port means through which the flow passes from the tool into the casing. The interior of this sleeve valve is exposed to well pressure within the tubing string. The exterior of this valve is arranged to be exposed to pressure derived from the well and introduced into an annular chamber in the tool through the pipe line eading down from its connection with the casing head which clearly balances the hydraulic forces on the valve. Spring means is associated with the sleeve valve to hold it in open position permitting flow to the top of the well.

The arrangement of the sleeve valve, annular chamber, and spring means is such that when equal fluid pressures are created interiorly and exteriorly of the valve, the spring means will maintain the sleeve valve in open position. However, if the fluid pressure exposed to the exterior of the valve in the annular chamber is vented to the atmosphere, the well pressure interiorly of the valve instantly becomes effective to move the valve into position to close the port means and thus shut the flow from the tool into the casing.

It is intended that this venting of pressure and consequent shutting olf of the flow at the tool take place responsive to the Well platform or other vulnerable parts of the well being subjected to blows or forces of such severity as would rupture the exposed part of the casing or flow lines connected thereto, such damaging action being likely as a result of collision with the well structure, of ships or floating or windblown objects in stormy weather.

It is also intended that this automatic shut-off of the well take place before the casing or flow lines at the top of the well become ruptured and permits of wasteful uncontrolled flow of the well. This is desired as the well pressure is depended upon to close the shut-off valve.

Accordingly, trigger means including a pressure actuated trigger valve, are provided at the top of the well to respond to the aforementioned severe collision shocks and similar shocks, so that the fluid pressure which is transmitted from the top of the casing to the annular chamber around the shut-off valve in the tool, will be vented to the atmosphere while the trigger valve shuts off communication between the casing and the pipe line leading to the annular chamber, thereby permitting the shut-off valve to respond to the Well pressure trapped in the tool and thus shut off the fiow at the tool.

As it may be desirable to remove the shut-off valve unit from the tool for inspection and replacement of parts thereof, provision is made for this removal. Accordingly, a latch means normally holds the valve unit in operative connection with the tool and is arranged so that when a fluid pressure greatly in excess of the normal well pressure is pumped down the pipe leading from a pump provided for the purpose at the top of the well, the latch means will release the valve unit for withdrawal from the tool by a wire line. The valve unit readily may be replaced on the tool on a wire line and spudded into latched engagement with the tool by use of a set of jars.

Provision is also made at the top of the well for manually venting at will, the annular chamber around the sleeve valve, to shut off the well fiow at the tool, there being a manually operable vent valve in the pipe line for this purpose.

As shown in FIG. 1, a typical use of apparatus embodying the present invention is illustrated in connection with a flowing well situated in a body of water. This well includes a platform A supported on pilings B, a derrick C, a casing D extending from the platform into the submerged ground E, and flow lines F connected in the usual manner with the casing head G.

A shut-off tool 1 embodying the present invention is located in the casing D and serves as a section of the tubing string S, only the lower part of this string being shown.

The tool I is anchored to the casing D at a safe distance, say, of the order of or more feet, below the surface of the submerged ground.

After the tool I is anchored in the desired position, that part of the tubing string above the tool is uncoupled and removed from the well. Next, the upper end of the tool is closed by lowering a tubing plug 2 and seating it in this upper end. The tool I is provided with ports 3 which permit of free flow of the well below the plug 2 into the casing to the top of the well.

Trigger means, generally designated T, are mounted on the platform A for controlling the tool 1 in a manner to be hereinafter described. A pipe line 4 extending from the top of the well to the tool 1 operatively connects the trigger means with the tool 1.

A trigger valve unit 5 embodied in the trigger means T, is connected with the pipe line 4 and the casing head G and normally causes the fluid pressure in the well to be effective through the line 4 to the tool 1 for control of.

the latter in a manner to be hereinafter described.

As it is the function of the tool to shut off the flow when an emergency arises, for example, in the event of the platform and vulnerable parts of the well being struck a severe and damaging blow by a ship, barge, or other floating object or an object blown against the Well during high winds and in stormy weather, the trigger means is arranged to respond to such accidentally applied forces and cause the tool to shut off the flow of the Well below the vulnerable parts of the well.

Accordingly, the tool 1 is provided with a spring-loaded shut-off valve unit 6 which is maintained in position with the ports 3 open but being counter-balanced by well pressure directed thereagainst from the pipe line 4 and the interior of the tool respectively. This valve unit, however, will move to a position closing the port 3 and shutting oif flow from the tool 1, incident to venting fluid from the tool through the line 4 to the atmosphere. This venting will take place responsive to operation of the trigger valve unit 5 in the pipe line 4 as a result of the trigger means T being subjected to the aforementioned shocks or forces.

As shown in FIG. lb, the trigger means T includes a valve chamber 5a rigidly secured to the casing head G and provided with an intake port 7, an outlet port 8 and a vent port 9. The port 7 is connected with the casing head by means of a pipe 4a, whereas the pipe line 4 leading to the tool 1 is connected with the outlet port 8.

Mounted to reciprocate in the chamber 5a is a valve stem on which are mounted piston-like valve members 11 and 12. The valve member 11 is movable between positions opening and closing a passage 11a extending between the

ports

7 and 8, Whereas the valve member 12 is movable between a position opening and closing a passage 12a between the ports 8 and 9.

The trigger means T also includes means which releasably holds the stem 10 in a position such that valve member 11 opens the passage 11a between

ports

7 and 8 and closes the passage 12a leading to the vent port 9. When the stem 16 is released, the fluid pressure applied to the valve chamber from the well casing through the pipe 4a is effective against the valve member 12 so that the valve members 11 and 12 are caused to move to positions closing the passage 11a and opening the passage 12a, thereby shutting off the flow from the well through the valve chamber and permitting the fluid pressure in the line 4 to vent to the atmosphere through the passage 12a and vent port 9.

Means for releasably holding the stem lit in position permitting fluid pressure from the well to be eifective in the pipe line 4, includes a disk 14 on the upper end of an upstanding post 15 rigidly secured at its lower end to an annular member 16. This annular member is positioned in an opening in the floor 17 of the platform A and has an annular flange 18 bolted to the floor. The well casing extends through the annular member 16 so that the latter is circumferentially spaced therefrom. The member 16 is preferably made in arcuate sections to facilitate the assembly thereof around the casing.

With this arrangement of the member 16 and post 15, it is apparent that lateral movement of the platform, member 16 and post 15 relative to the casing will take place incident to the pilings or the platform being subjected to severe impacts such as described. Accordingly, the disk 14 on the post 15 will be moved laterally with the platform and annular member 16 to one side of the stem 10 which, as hereinbefore noted, will then be moved by the fluid pressure from the well, into position to shut olf flow into the line 4 and open line 4 to the vent port 9 whereby the shut-off valve in the tool 1 will be closed.

As here shown, the stem 10 rests upon the center of the disk 14, as it is intended that the diameter or width of this disk be such that only when a severe impact such as would rupture the casing or flow lines at the top of the well, is sustained by the platform, will the disk 14 be moved sufiiciently to release the stem and thereby cause the tool 1 to shut off flow into the well casing. Thus, it is apparent that by varying the diameter or width of the disk 14, the trigger means T may be set to cause the flow to be shut off at the tool 1 as best suited to the conditions at hand and so that anticipated minor shocks and jars be ineffective to trip the trigger means.

The shut-off tool 1 as shown in FIGS. 1-6 includes a tubular body 20 adapted to be coupled in the tubing string as a section thereof. A tubular plug seat 21 connects the upper end of the body 20 with the portion of the tubing string above the tool in such manner that after the tool is set in the desired position in the well casing, the portion of the tubing string above the plug seat may be uncoupled from the latter and removed from the well. After this upper portion of the tubing string is removed, the tubing plug 2 is lowered and set in the seat 21 to shut off flow from the seat into the well casing.

A sectional tubular member 22 surrounds the body 20 in circumferentially spaced relation thereto to provide an annular passage 23 therebetween. A coupling member 24' having ports 24 therein, provides for connection of the body 20 with that portion of the tubing string extending below the body, as well as for connection of the outer tubular member 22 with the body 1 and tubing string. The ports 24 provide for the flow of the well fluids from the casing below the tool into the annular passage 23, thence through the ports 3 into the casing above the tool.

The upper part of the outer tubular member 22 comprising the threadedly connected

tubular sections

26, 27 and 28 forms a part of the retrievable shut-off valve unit 6, wherein the valve element comprises a sleeve 29 movable axially between positions opening and closing the ports 3, which latter are formed in the tubular section 27. The remainder of the sectional tubular member 22 includes

tubular sections

30, 31, 32, and 33 thrcadedly connected one to the other and located in the order named, below the sleeve valve 29 and the tubular section 28. In this connection, it should be noted that the lower end of section 28 is telescopically and removably fitted in a counterbore 3% in the section 30 so that the valve unit 6 may be removed as will be hereinafter described.

The

tubular sections

27 and 28 and the sleeve valve 29 are constructed and arranged to define an annular pressure chamber 34 between the exterior of valve 29 and the interior of the

sections

27 and 28. Thus, the upper portion of the sleeve valve 29 is slidably engaged with an internal enlargement 35 of the section 27, which latter defines a shoulder 36 forming the upper end of the chamber 34, there being a sealing ring 37 on this enlargement for sealing against the sleeve valve. In this connection, it should be noted that the sleeve valve 29 is circumferentially spaced from the body 20 so that the resultant annular space therebetween becomes a part of the fluid passage 23 between the ports 24 and the ports 3 at the respective ends of passage 23. The upper end of this passage is closed by on internal enlargement 38 in the uppermost tubular section 26, there being a sealing ring 39 in this enlargement to seal against the body 2i).

The lower end of the sleeve valve 29 is provided with an external flange 4t) slidably engaged with the internal surface of the tubular section 28 to define the lower end of the pressure chamber 34, there being a sealing ring 41 in the flange 40 for sealing against the section 28.

The pipe line 4 is connected with a port 42 formed in the tubular section 30 of the outer tubular member 22, this port being in communication with a passage 43 formed in the tubular section 28. The passage 43 opens through a port 44 into the pressure chamber 34, thereby providing for the introduction of well pressure through the line 4, port 42, passage 43, and port 4 into the chamber 34, whereby the fluid pressure against the exterior of the sleeve valve 29 may be equalled to the pressure within the passage 23, to hydraulically balance the sleeve valve when it is in the open position. Sealing rings 45 and 46 carried by the section 28 are arranged to seal against the section 30 above and below the point of communication of the port 42 with the passage 43.

To assure that the sleeve valve 29 be maintained in open position uncovering the ports 3, a spring 47 is mounted in the chamber 34- in surrounding relation to the sleeve valve with its ends abutting the shoulder 36 and flange 46 respectively.

Latch means are provided for releasably holding the section 28 in coupled relation to the section 30. This latch means includes a series of spring latch elements 48 integral with a tubular member 49 threadingly coupled to the section 30. These latch elements releasably engage a shoulder 50 internally of the section 28 below the valve 29. The outer ends of the spring latch elements 48 have cam surfaces 51 which are engaged by an annular cam surface 52 on the lower end of the sleeve valve 29 when the latter is in a poistion uncovering the ports 3 as shown in FIG. 3. When in this position, the valve 29 is above a shoulder 53 on the section 28, this shoulder acting as a stop when the valve is moved downwardly for forcing the spring latch elements 48 out of latching engagement with the latch shoulder 59.

When it is desired to release the valve unit 6, which includes the upper

tubular sections

26, 27, and 28 and the sleeve valve 29, pump P such as shown in FIG. 1 in dot dash lines, is connected with the line 4 and operated to force fluid under pressure greater than the well pressure, into the chamber 34. This greater pressure will cause the valve 29 to move downwardly against the stop shoulder 53 and in so moving the cam surfaces 51 and 52 cooperate to force the latch elements into releasing position shown in FIG. 5. The valve unit 6 may now be removed with a wire line, for inspection or parts replacement, and tl ereafter replaced by the aid of a wire line and jars to snap it into latched engagement with the latch members .9.

Packing means are provided on the tool for sealing against the casing and, as shown in FIG. 2a, includes an expansible sleeve packer 55 confined on the section 32 between a shoulder 56 on the section 32 and a floating slip expander 57 surrounding the

sections

32 and 33. This packer is normally relaxed and free from contact with the casing whereby the tool readily may be lowered into the well casing on the tubing string.

Slips 66 are engaged with the expander 57 so as to be moved laterally into anchoring engagement with the casing responsive to relative movement between the slips and the expander. These slips are connected by links 61 with a floating sleeve 62 mounted on the tubular section 33. The sleeve 62 mounts a plurality of spring loaded shoes 64 which are employed instead of conventional drag springs, to frictionally engage the casing whereby relative movement between the slip and the slip expander may be effected upon lowering of tubing string.

Means are provided for releasably locking the slips 6%) in retracted position as well as for holding the sleeve packer 55 in relaxed position free from contact with the casing. In other words, this locking means releasably holds the sleeve 62 and tubular members 21: and 22 against relative axial movement, but permits of relative rotation between the sleeve and

members

20 and 22 to release sleeve 62 and

members

20 and 22 for relative axial movement. As here shown, the locking means includes a plurality of locking segments 65 confined between op posed shoulders d6 and 67 on threadedly connected tubular members 68 and 169. The tubular member 68 is threadedly coupled to the lower end of the sleeve 62. The segments 65 have screw threads 69 on the inner surfaces thereof and are held in annular formation around the tubular section 33 by means of a pair of coiled springs 70 which surround the segments and are seated in grooves 71 on the outer surfaces of the segments. With this arrangement the segments 65 are yieldable radially but are held against rotative movement by lugs 72 welded to the member 68 and extending between the segments as indicated in FIG. 2b.

The other element 73 of the locking means is in the form of a screw threaded enlargement on the exterior of the tubular section 22. The screw threads on the segments 65 cooperate to threadedly engage the screw threaded element 73 for locking the sleeve 62 and

tubular members

29 and 22 against relative axial movement. These coacting screw threads are of such formation that upon appropriate rotative movement of

members

20 and 22 relative to the sleeve 62, the screw threaded element 73 will be unscrewed from the segments 65 and lowered relative thereto, the shoes 64 then restraining rotation of the sleeve 62. When it is desired to relock the element 73 with the segments 65, it is only necessary to lift the

members

20 and 22 so that the element 73 will snap into locked engagement with the segments 65. The screw threads on the segments 65 and locking element 73 are shaped so as to cam past one another as the element 73 is moved upwardly against the segments 65, the latter yielding radially outwardly against the action of the springs 70 during this camming action and then urging the segments into threaded and locked engagement with the enlargement 73.

Additional anchoring means is provided on the tool to hold the latter in place, in the event the shut-off valve unit, that is, the sleeve valve 29, is moved into position to close the ports 3 and thus shut oir the flow at the tool 1. This additional locking means is actuated by the fluid pressure in the well when the latter is shut oif at the tool and includes a plurality of rows of axially spaced cylinders 75 formed in the tubular section 31. Pistonlike slips '76 are mounted in the cylinders so that the toothed outer ends of the slips are disposed to grip the casing. These fluid pressure actuated slips are normally substantially hydraulically balanced and ineffective for anchoring the tool until the well flow is shut off at the tool as hereinbefore noted. When the flow is shut off at the tool the pressure drop across the outer ends of the slips 76 permits the pressure against the inner ends of the slips to urge the slips into anchoring engagement with the casing.

As shown in FIG. 2, a sleeve is mounted within the tubular section 31 in circumferentially spaced relation to body 20 as well as to the inner ends of the cylinders 75, to define an annular pressure chamber 78. This pressure chamber is in constant communication with the passage 23 through a port 79 at the lower end of the sleeve 77. The sleeve 77 is confined between

shoulders

80 and 81 on the

tubular sections

30 and 31 respectively.

Provision is made for manually shutting off the well at the tool 1. Accordingly, the pipe line 4 at the top of the well is provided with a vent pipe 83 controlled by a valve 84. When the valve 84 is opened, the fiuid pressure in the chamber 34 of the valve unit 6 is vented to the atmosphere; whereupon the fiuid pressure interiorly of the sleeve valve 29 will be effective to move the sleeve valve upwardly to close the ports 3 thereby shutting oil the flow of the well at tool ll.

Other controls of the flow in the pipe lines 4a and 4 at the top of the well include a manually operable valve 85 in the line 4 a between the casing head and trigger valve unit 5, a similar valve 86 between the trigger valve unit 5 and the line 4 leading to the shut-off valve unit 6 in the tool 1, and a manually operable valve 87 in a pipe 38, which latter provides for connection with the pump P with the line 4. This connection of the pump P is made when it is desired to retrieve the shut-01f valve unit 6 in the manner hereinbefore described. This arrangement of valves 85, 86, and 87 provides for a complete manual control of the flow through the lines 4:! and 4.

It should be noted that the tubing plug 2 is provided with a neck 2a whereby standard wire line equipment,

sisasoo 9 not shown, may be employed to remove and replace the plug.

As shown in FIGS. 3 and 13, lugs 89 are provided on the lower end of the telescopically mounted tubular section 28 for contacting similar lugs 90 on the tubular section 30 in which the section 28 is telescoped.

Operation A tubing string, only the lower part S of which is here shown, is employed to position the tool 1 with the pipe line 4 in the well casing at the desired location below the surface of the submerged ground.

After the tool is disposed at the desired depth, the tubing string, together with the

tool members

20 and 22, are appropriately rotated to unscrew the locking element 73 from the locking segments 65 on the floating sleeve 62. This sleeve is restrained against rotation by the friction shoes or engaged with the casing.

When the locking element 73 is released from the segments 65 the

tool members

20 and 21 may be moved axially relative to the sleeve 62, which latter is then restrained against axial movement by the shoes 64 engaged with the Well casing.

Upon now moving the tubing string downwardly, the

tool members

20 and 22 move correspondingly and through the sleeve packer 55 exert a force urging the expander '7 downwardly relative to the slips 69, thereby moving the slips into engagement with the casing and anchoring the tool in the well. This anchoring action causes the packer 55 to be expanded into sealing engagement with the casing.

Next, the portion of the tubing string leading upwardly from the plug seat 21 at the top of the tool is uncoupled and removed irom the well. The seat 21, in effect, is now the upper end of the tubing string in the well, and is plugged by lowering the plug 2 into the seat on a wire line.

The pipe line 4, trigger valve unit 5 and related trigger elements are now set up at the top of the well, with the valve unit 5 and line 4 in communication with the casing head. The valve unit 5 and line 4 provide for the introduction of the fluid pressure in the well into the chamber 34 in the shut-ofl valve unit 6 in the tool, thereby, as hereinbefore described, hydraulically balancing the sleeve valve 29 so that the spring 47 will be eiiective to assure holding the valve open whereby normal flow of the well may take place.

When the tool is anchored in the casing :and the valve 29 balanced and held open, the tool is in readiness to protect the well. At this time the hydraulically actuated slips 76 are ineflective to anchor the tool as the fluid pressure of the well is effective against the outer ends of the slips as well as against the inner ends thereof.

In the apparatus shown in FIGS. 1-6, the lower part of the well is arranged so that the well fluid will enter the tool from the portion of the casing next below the tool, rather than from that portion of the tubing string S adjacent the tool. It is believed to be unnecessary to illustrate the arrangement of the well which provides for the flow of the well products through the tool, as it is plain that the upwardly flowing products, in the casing below the tool, will enter the tool through the ports 24 and flow through the annular passage 23 and ports 3 into the casing above the tool, thence to the top of the well.

It will now be apparent that with the tool 1 installed in a well as shown in FIGS. 1 and 1a, should the platform A or pilings B, sustain collision forces or similar impacts of a severity which would damage the well and cause loss of the well products, the platform will move relative to the well casing and cause the disk 14 to move clear of the valve stem 10 of the trigger valve unit 5. When this action takes place the fluid pressure of the well elfective in the valve unit 5 will cause the valve member 12 to move to a position (see FIG. 1b) communicating the pipe line 4 with the vent port 9, at the same time the valve member 11 shuts ofl the flow from the well to the pipe line 4, thereby relieving the pressure in the chamber 34 of the valve unit 6. Incident to this release of the fluid pressure from the chamber 34, the fluid pressure in the passage 23 is eiiective against the interior surface of the sleeve valve 29 and causes this valve to move upwardly against the action of the spring 47 into a position closing the ports 3 and shutting off the flow at the tool.

It will be apparent that a shut-off tool such as hereinbefore described, when installed in a well and arranged to be operated responsive to the trigger means T as here shown, will prevent the loss of valuable products of the well, in the event the vulnerable portion of the well at the surface is subjected to damaging shocks and imp-acts.

As shown in FIGS. 7-l1, a modified form of "shut-off tool embodying the present invention, ditiers from the tool shown in FIGS. 1-6 in that it does not include a sectional tubular member jacketing the tool body, such as the member 22 forming the outer section of the tool shown in FIGS. 16. Instead, the modified tool includes a sectional tubular body 160 which is adapted to be connected in a tubing string in the same manner as the body 20 in the tool shown in FIGS. 1-6, and provided at its upper end with a plug seat 101 for reception of a plug to shut Off flow of well fluid through the plug seat.

This tool is installed in the same manner as the tool shown in FIG. 1, subject to control by the same trigger means as shown in FIGS. l-lb including a pipe line 1132 leading to a pressure chamber 103 surrounding a sleeve valve 164. This sleeve valve corresponds to sleeve valve 29 shown in FIG. 2, being axially movable within the body 166 between positions for opening and closing ports 195 formed in the upper end of the body ltit). The ports 105 when uncovered by the valve 1114 provide for normal flow of the well fluids from the tubing string V below the tool, through the body ltltl and into the casing 106, thence to the top of the well.

A spring 197 surrounds the sleeve valve 104 with its ends abutting shoulders '108 and 1119 on the body 1% and valve respectively, for normahy holding the valve in open position.

The pipe line 102 is connected with a port 1 10 in a section 111 of the body 1%, this port being in communication with a passage 112 formed in the section 113 of the body 111% leading into the chamber 163 in the same manner as shown in FIG. 3. When the fluid pressure from the casing head is conducted through pipe line 102 into the chamber 163, the exterior of the valve 134 is exposed to substantially the same pressure as the interior of the valve, thereby providing -a hydraulic balance whereby the spring 1117 is eifective to hold the valve in open position as shown in FIGS. 7 and 8.

When the fluid pressure is relieved from the chamber 103 through the line 192 and trigger means in the same manner as described in connection with the apparatus shown in FIGS. 1-6, the fluid pressure in the body 1% becomes eflective against the valve 194 and moves the valve against the action of the spring 1&7 into position to close the ports 195.

The plug seat 1111 and the threadedly connected

tubular sections

115 and 113 of the body 1011, together with the sleeve valve 164 constitute a retrievable unit as the lower section 113 is telescopically and removably mounted in the section 111 of the body 109.

Latch means identical with the latch means shown in FIGS. 2 and 3 are provided for releasably holding the tubular section 113 in telescopic engagement with the section 111. This latch means comprises spring latch fingers 117 fixedly connected with the section 7111 and arranged to engage an internal shoulder 1-18 on the section 113. The lower end of the valve M14 is provided with a cam surface 120 normally in contact with the cam surfaces 121 on the free ends of the latch fingers 117.

When it is desired to release the valve unit, fluid pressure in execss of the well pressure is pumped down the pipe line 192 from the top of the well in the same manner as described in connection with the first described form of this invention.

The fluid pressure thus developed in the chamber 103 will be effective to force the valve 104 downwardly whereby the cam surfaces will coact to force the fingers 117 inwardly free of the shoulder 118, thereby releasing the valve unit, which may be removed and replaced on a wire line.

This modified tool is provided with expansible packing rings 123, a floating slip expander 124, slips 125, and links 126 connecting the slips with a floating sleeve 127, all mounted on the body 100. The sleeve 127 carries spring-loaded shoes 128 for frictionally engaging the casing.

The expansible ring packers 123 are confined between a shoulder 129 or the body 160 and the upper end of the expander 124 whereby on moving the body downwardly relative to the sleeve 127, the ring packers will force the expander downwardly to set the slips. Continued movement of the body 101 downwardly will cause the packers to expand into sealing engagement with the casing.

Locking means 131 substantially identical with the locking means shown in FIGS. 2a and 2b are provided for holding the sleeve 127 and body 120 against relative axial movement. This locking means includes springloaded screw threaded segments 132 on the sleeve 127 and a screw threaded locking element 133 on the body 100. Lugs 133' on the sleeve extend between the segments 132 to hold them against rotation. The locking segments and the element 133 are operable in the same manner as described in connection with the tool shown in FIGS. 16.

A hydraulically actuated anchoring unit 134 is provided on body 100 between the packer rings 123 and the body section 111. This unit includes cylinders 135 formed in the body 1% and piston-like slips 136, identical with the cylinder slips shown in FIG. 2. A tubular member 137 is mounted in the body 100 in spaced relation to the inner ends of the cylinder 135 to define an annular pressure chamber 139. A port 140 in this tubular member 137 provides for the introduction of the fluid pressure from the body 101 into the chamber 139 for forcing the slips 136 into anchoring engagement with the casing. However, when the valve 194 is open, the fluid pressure exteriorly of the body 100 against the outer ends of the slips is substantially equal to the fluid pressure in the chamber 139 whereby the slips are substantially hydraulically balanced. When the pressure in the chamber 139 increases incident to the closing of the sleeve valve 104, the slips 135 will be forced by the increased pressure into anchoring engagement with the casing. With this arrangement the anchoring action increases according to the increased well pressure, thereby assuring that the tool will remain properly anchored in the well while the valve 164 shuts ofl? flow from the tool to the top of the well.

Provision is made in this modified tool to prevent rotation of the valve unit including the

tubular sections

115, 113 and the sleeve valve 154 relative to the remainder of the body 190, in the same manner as in the tool shown in FIGS. l6. Accordingly, lugs 143 and 144 on

sections

113 and 111 respectively, are adapted to engage one another to prevent such rotation, these lugs being the same construction and arrangement as the lugs 85* and 30 shown in FIG. 13. In this modified construction it may be desirable to make up a tubing string in the plug seat 161 while the tool is in the well, and the lugs 143 and 144 will prevent relative rotation of the tubular member 113 within the body member 111.

FIG. 12 illustrates another modified form of tool 146 embodying this invention, wherein the same elements as in the tool shown in FlGS. 1-6 are provided except that the packing means including an expansible sleeve packer 147, is actuated in a different manner than in the tool shown in FIGS. 16. In the tool 146, the casing 148 is provided with a conical restriction 149 in which a floating conical member 150 is engageable. The sleeve packer 147 is confined between the upper end of the conical member and a shoulder 151 on the sectional outer tubular member 152 of the tool. The tubular body 153 of the tool is connected in the tubing string 154 in the same manner as the body 20 of the tool shown in FIGS. 1-6. The body 153 and the outer sectional tubular member 152 are connected with one another and the tubing string by means of a coupling member 155 in the same manner as shown in FIG. 2a, there being ports 156 in the member 155 corresponding to the ports 24 shown in FIG. 2a.

The packer 147 is expanded into sealing engagement with the casing 148 by lowering the tubing string and

tubular members

152 and 153 of the tool, thereby compressing the packing between the member 150 and the shoulder 151. In all other respects the tool 146 is operated in the same manner as the tool shown in FIGS. 16.

There is illustrated in the drawings and described above a subsurface valve assembly 6 in which the spring 47 acts on the valve sleeve in a direction such as to supplement the force derived from the action of pressure in the control tube 4 on the surface of flange 40 in the chamber 34 of the valve assembly. It will be understood, however, by those of ordinary skill in the art that the position of valve sleeve 29 in the body 27 will be determined by the net force acting in one direction or the other to move the valve sleeve to an open position or to hold the valve sleeve in such position or to move the valve sleeve to a closed position. Obviously, therefore, the spring is not essential to opening or holding open of the valve 6, since fluid pressure alone in chamber 34, supplied through control tube 4, and acting on the valve sleeve flange 4%) plus the weight of the valve and friction is suflicient to overcome the effect of well pressure acting oppositely on the flange 4t and thereby maintain the valve in open position.

Within the clear purview of the various modes of controlling the position of the valve sleeve 29, venting of the control tube to atmosphere may be accomplished by means of the trigger valve 5 hereinabove described, by the manual vent valve 84 or by other desired valve means, as well as upon rupture of the well head equipment, as is obvious, in any of which cases pressure in the well may cause closure of the valve.

Whether or not the spring 47 be present in the valve assembly 6, the valve will be opened and/ or held open when the force acting downwardly on valve sleeve 29 overcomes the force acting upwardly thereon. When it is desired to open the valve assembly 6, as is apparent from the foregoing, it is only necessary to supply sufficient pressure through control tube 4 to the valve chamber 34 to overcome the upward forces thereon, thereby moving the valve sleeve downward to the position shown in FIG. 3, for example, wherein the ports 3 are open. The flow of production fluid to the top of the well through ports 3 will provide, in accordance with one of the features of the invention, fluid pressure whereby the valve sleeve 29 may be held open. One source of fluid pressure for opening the valve as aforesaid has been described above as being useful also to move the valve sleeve 29 downwardly to unlatch the fingers 43 from the valve body. Obviously, the pressure source or pump P is also useful to move the valve to an open position and the pump P therefore is preferably a source of variable pressure, since a substantially greater pressure would be required to unlatch the fingers 48 than would be required merely to open the valve 6.

The various structural details as herein shown and described are by way of illustration of an embodiment of the invention, but changes and alterations may be resorted 13 to and equivalent sub-assemblies and components may be employed without departing from the scope of the following claims.

We claim:

1. Apparatus for protecting a flowing well against the loss of fluid products of the well from a conduit at the top of the well, including: means at the top of the well adapted to be moved by forces which if sustained by the conduit at the top of the well would cause such loss; valve means located in the well below said flow structure, said valve means including a body open to Well fluids therebelow and having a passage leading to the well above the valve means from said body; a valve element in said body shiftable to a position closing said passage to close the valve means and to a position spaced from said passage to open the valve means; said element having a first fluid pressure responsive surface for hydraulically holding said valve means open and a second fluid pressure responsive surface for hydraulically closing said valve means; and means including a conduit connected with said first named means, said flow conduit and said valve means for conducting fluid under pressure from said flow conduit to said first fluid pressure responsive surface to permit flow of the Well.

2. A well tool including: a tubular body adapted to be anchored in a well; packing means on the body operable for sealing against the Wall of the well; anchoring means on the body operable to anchor the tool in the well; valve means in the body for controlling the well flow through the body; means associated with said valve means operable for maintaining said valve means open when the valve means is hydraulically balanced in the well; said valve means being constructed and arranged to be closed by the fluid pressure in the well when hydraulically unbalanced in the well; and hydraulically operable anchoring means carried by said body operable to anchor the tool in the well responsive to the fluid pressure in the well upon the closing of said valve means.

3. A well tool including: a tubular body adapted to be anchored in a well; packing means on the body operable for sealing against the wall of the well; anchoring means on the body operable to anchor the tool in the well; valve means in the body for controlling the well flow through the body; and means associated with said valve means operable for maintaining said valve means open when the valve means is hydraulically balanced in the well; said valve means being constructed and arranged to be closed by the fluid pressure in the well when hydraulically unbalanced in the well; said valve means including means adapted to be controlled from the top of the well for effecting said hydraulic balance as well as said hydraulic unbalance; and hydraulically operable anchoring means arranged to be substantially hydraulically balanced and ineifective as an anchor when said valve means is hydraulically balanced; said hydraulically operable anchoring means being operable to anchor the body in the well responsive to the fluid pressure in the well when said valve means is closed.

4. A well tool including: a tubular body adapted to be anchored in a well; packing means on the body operable for sealing against the Wall of the Well; anchoring means on the body operable to anchor the tool in the well; said body having a port above said packing means for conducting fluid from said body into the well above said body; a sleeve valve shiftably disposed in said body; means for shifting said sleeve valve in opposite directions to open and close said port including internal and external surfaces on said sleeve valve responsive to fluid pressure; said internal surface being exposed to well fluid pressure; means including a conduit leading from the top of the well for conducting well fluid pressure to said ex ternal valve sleeve surface; and means at the top of the well and connected with said conduit for controlling the application of well pressure through said conduit to said external sleeve valve surface to cause said port to be maintained open.

5. A well tool including: a tubular body adapted to be anchored in a well; packing means on the body operable for sealing against the wall of the well; anchoring means on the body operable to anchor the tool in the well; said body having a port above said packing means for conducting fluid from said body into the Well above said body; a sleeve valve associated with said body for opening and closing said port; said valve having its internal and external surfaces exposed for application thereto of fluid pressure; a conduit connectable to a source of well fluid pressure at the top of the well and connected to said body above said packing means and below said port for applying fluid pressure externally of said valve; and means operable at the top of the well and connected with said conduit for controlling the application of fluid pressure externally of said valve to cause said valve to be held open and closed responsive to fluid pressure derived from the well.

6. A well tool adapted to be anchored in a well, including: a tubular body for conducting fluid therethrough; a packer on said body for sealing against the wall of the well; means on the body for anchoring the body in the well; said body having a port above said packer for conducting fluid into the well above said body; a sleeve valve in the body movable axially to close and open said port; means providing a pressure chamber on the body surrounding the exterior surface of said valve; the interior surface of said valve being positioned for exposure to fluid pressure in said body; said valve being hydraulically balanced when fluid pressure is applied internally and externally thereof: spring means urging said valve to a position opening said port when said valve is hydraulically balanced; a conduit connected to said body and leading to said pressure chamber and to the top of the well; and means connected to said conduit at the top of the well for introducing fluid pressure into said conduit and consequently said chamber and venting fluid pressure from said conduit and consequently said chamber to hydraulically balance and unbalance said valve.

7. A well tool adapted to be anchored in a well, including: a tubular body for conducting fluid therethrough; a packer on said body for sealing against the wall of the well; means on the body for anchoring the body in the well; said body having a port above said packer for conducting fluid into the well above said body; a sleeve valve in the body movable axially to close and open said port; means providing a pressure chamber on the body surrounding the exterior surface of said valve; the interior surface of said valve being positioned for exposure to fluid pressure in said body; spring means urging said valve to a position opening said port; means on said body providing a passage adapted to be controlled from the top of the well for introducing fluid pressure into said chamber and venting fluid pressure from said chamber; and hydraulically actuated anchoring means on said body above said packing means operable to move into anchoring engagement with the wall of the well responsive to fluid pressure in the well above the packer when said valve closes said port.

8. A well tool adapted to be anchored in a Well, including: a tubular body composed of a pair of concentric circumferentially spaced tubular members defining an annular flow passage; said body having upper and lower ports which open into said passage; a sleeve valve axially movable between said tubular members for opening and closing said upper port; means providing a pressure chamber between said tubular members below said upper port and in surrounding relation to said valve; the interior surface of said valve being exposed to fluid pressure in the well; packing means on said body below said chamber for sealing against the well wall; means on said body for anchoring said body in a well; said valve being hydraulically balanced when fluid pressure is applied to the exterior and interior thereof; spring means surrounding said valve in said chamber urging said valve to open said upper port while said valve is hydraulically balanced; and passage means in said body leading into said chamber from the exterior of said body for introducing fluid under pressure from the Well above said body into said chamber as well as for venting fluid from said chamber.

9. A well tool adapted to be anchored in a well, including: a tubular body composed of a pair of concentric circumferentially spaced tubular members defining an annular flow passage; said body having upper and lower ports adjacent its ends opening into said passage; a sleeve valve axially movable between said tubular members for opening and closing said upper port; the interior of said valve being exposed in said flow passage; means providing a pressure chamber within the outer tubular member of said body below said upper port and in surrounding relation to said valve; said chamber providing for hydraulically balancing said valve when equal fluid pressures are provided in said flow passage and said chamber; a packing means on said outer tubular member below said chamber for sealing against the well wall; means on said outer tubular member for anchoring said body in a well; spring means surrounding said valve in said chamber urging said valve to open said upper port; and passage means in said outer tubular member for introducing fluid under pressure from above said body into said chamber as well as for venting fluid from said chamber.

10. A well tool adapted to be anchored in a well, including: a tubular body composed of a pair of concentric circumferentially spaced tubular members defining an annular flow passage; said body having upper and lower ports adjacent its ends opening into said passage; a sleeve valve axially movable between said tubular members for opening and closing said upper ports; the interior of said valve being exposed in said flow passage; means providing a pressure chamber within the outer tubular member of said body below said upper port and in surrounding relation to said valve; said chamber providing for hydraulically balancing said valve when equal fluid pressures are provided in said flow passage and said chamber; a packing means on said outer tubular member below said chamber for sealing against the well Wall; means on said outer tubular member for anchoring said body in a well; spring means surrounding said valve in said chamber urging said valve to open said upper port; and passage means in said outer tubular member for introducing fluid under pressure from above said body into said chamber as well as for venting fluid from said chamber; and means for anchoring said body in the well mounted on said outer tubular member for operation by fluid pressure in said flow passage incident to the closing of said upper port.

11. A well tool adapted to be embodied in a well, including: a tubular body having a port for conducting fluid into the well above the body; packing means on said body below said port for sealing against the wall of the well; means on said body for anchoring the body in the well; a sleeve valve axially movable within said body for opening and closing said port; the interior surface of said valve being exposed to pressure of well fluid; means on said body providing a pressure chamber surrounding said sleeve and providing for hydraulically balancing said valve when fluid pressure in said chamber against the exterior of said valve is equalled to fluid pressure in said body against the interior of said valve; spring means in said chamber surrounding said valve urging said valve to position opening said port when said valve is hydraulically balanced; and means on said body providing a passage for introducing well pressure from the exterior of said body into said chamber as well as for venting fluid pressure from said chamber.

12. A well tool adapted to be anchored in a well, including: a tubular body; an expansible packer on said body; means on said body for anchoring the body in the well; means on said body operable for expanding said packer into sealing engagement with the wall of the well responsive to actuation of said anchoring means; said body having a port above said packer for conducting fluid from below the body into the well above the body; a sleeve valve associated with said body for move ment to open and close said port; said valve means being positioned for exposure to the well pressure in said body; means providing a pressure chamber on said body surrounding said valve; means on said body above said packer providing a passage for conducting the fluid in the well above said body into said chamber as Well as for venting fluid from said chamber; spring means in said chamber urging said valve into a position opening said port and yielding to permit said valve to close said port responsive to the fluid pressure in said body eflective against said valve, when the pressure in the chamber is vented therefrom; and hydraulically operated anchoring means operable to anchor the body in the well responsive to the closing of said valve.

13. A well tool including: a tubular body adapted to be positioned in a well on a tubing string; a tubular plug-receiving seat for detachably connecting the upper end of the body with the tubing string; means on the body for anchoring the body in the well; said seat adapted to be closed by a plug after detaching from the seat and removing from the well the portion of the tubing string extending from the seat to the top of the well; said body having a port below said plug seat for conducting fluid from the tool into the well above the body; packing means on the body below said port for sealing against the wall of the well; valve means on the body for opening and closing said port; and means embodied in the tool for causing said valve to open and close said port; said last named means being constructed and arranged to be controlled from the top of the well.

14. A well tool including: a tubular body; means on the body for anchoring the body in the well; a retrievable valve unit on said body; said valve unit including tubular means surrounding said body and defining a pressure chamber having a port for conducting fluid under pressure into and from said chamber; a sleeve valve in said chamber surrounding said body; said tubular means having a port above said chamber for conducting well fluid from the body into the well above the body; said sleeve valve being movable to open and close said second named port; latch means on said body for releasably holding said tubular means in operative engagement with said body; said latch means including spring latch elements on said body releasably engaged with said tubular means and disposed to be engaged by said sleeve valve and moved thereby to release said tubular means upon movement of said valve in one direction responsive to a fluid pressure in said chamber.

15. A well tool including: a tubular body; means on the body for anchoring the body in the well; a retrievable valve unit on said body; said valve unit including tubular means surrounding said body and defining a pressure chamber having a port for conducting fluid under pressure into and from said chamber; a sleeve valve in said chamber surrounding said body; said tubular means having a port above said chamber for conducting well fluid from the body into the well above the body; said sleeve valve being movable to open and close said second named port; latch means on said body for releasably holding said tubular means in operative engagement with said body; said latch means including spring latch elements on said body releasably engaged with said tubular means and disposed to be engaged by said sleeve valve and moved thereby to release said tubular means upon movement of said valve in one direction responsive to a fluid pressure in said chamber exceeding the fluid pressure of the well.

16. A well tool including: a tubular body; means on the body for anchoring the body in the well; a retrievable valve unit on said body; said valve unit including tubular means surrounding said body and defining a pressure chamber having a port for conducting fluid under pressure into and from said chamber; a sleeve valve in said chamber surrounding said body; said tubular means having a port above said chamber for conducting well fluid from the body into the well above the body; said sleeve valve being movable to open and close said second named port; and means for releasably holding said valve unit in operative connection with said body including, spring latch members on said body engageable with said tubular means; and cooperable cam surfaces on said valve and said latch members operable to disengage said latch member from said tubular means upon movement of said valve means responsive to a fluid pressure in said chamber exceeding the well pressure.

17. Apparatus for protecting a flowing well having casing therein against the loss of the fluid products therefrom in the event the structure of the well above the ground is subjected to a damaging force, including; means operatively connected with said structure arranged to be subjected to such a force and moved before the casing of the well is subjected to said force; and means located in the well and connected with said first named means for shutting oif the flow of the well responsive to said first named means being moved when subjected to said force; said means for shutting off well flow including a fluid pressure operated valve, and means for subjecting said valve to pressure from the well at the ground surface for maintaining said valve open.

18. Apparatus for protecting a flowing well against the loss of the fluid products therefrom in the event the structure of the well above the ground is subjected to a damaging force, including: a tubular body positioned in the well casing; said body having a port for conducting fluid from below the body into the well above the body; a sleeve valve axially movable in said body to open and close said port; means providing in the body a pressure chamber surrounding said valve; said valve being positioned for exposure of its interior and exterior surfaces to the pressure of fluid in said body and said chamber respectively, whereby the valve may be substantially hydraulically balanced; spring means urging said valve to a position opening said port; a fluid line connecting the casing at the top of the well with said chamber for conducting fluid under pressure from the casing to said chamber, as well as for venting fluid under pressure fromsaid chamber; trigger valve mechanism at the top of the well for controlling the flow through said line; said trigger valve mechanism including a vent port and valve means; said valve means being biased by fluid pressure from the well to occupy a position shutting off flow of well fluid through said line to said pressure chamber and permitting the venting of fluid from said chamber and said line through said vent port; and trigger means releasably holding said valve means in a position closing said vent port and permitting flow of well fluid through said line into said pressure chamber; said trigger means including a member operatively connected with said structure at the top of the well for movement relative to the well casing and said flow line, upon being subjected to said force; and means operatively connecting said member with said valve means for releasing said valve means responsive to said member being moved a predetermined extent relative to said casing when subjected to said force.

19. Apparatus for protecting a flowing well against the loss of the fluid products therefrom in the event the structure of the well above the ground is subjected to a damaging force, including: a tubular body positioned in the well casing; said body having a port for conducting fluid from below the body into the well above the body; a sleeve valve axially movable in said body to open and close said port; means providing in the body a pressure chamber surrounding said valve; said valve being positioned for exposure of its interior and exterior surfaces to the pressure of fluid in said body and said chamber respectively,

whereby the valve may be substantially hydraulically balanced; spring means urging said valve to a position opening said port; a fluid line connecting the casing at the top of the well with said chamber for conducting fluid under pressure from the casing to said chamber, as well as for venting fluid under pressure from said chamber; trigger valve mechanism at the top of the well for controlling the flow through said line; said trigger valve mechanism including a vent port and valve means; said valve means being biased by fluid pressure from the well to occupy a position shutting off flow of well fluid through said line to said pressure chamber and permitting the venting of fluid from said chamber and said line through said vent port; and trigger means releasably holding said valve means in a position closing said vent port and permitting flow of well fluid through said line into said pressure chamber; said trigger means including a member operatively connected with said structure at the top of the well for movement relative to the well casing and said flow line, upon being subjected to said force; and means operatively connecting said member with said valve means for releasing said valve means responsive to said member being moved a predetermined extent relative to said casing when subjected to said force; and means operatively connected with said flow line optionally operable for venting fluid pressure from said chamber.

20. Apparatus for protecting a flowing well against the loss of the fluid products therefrom in the event the struc- .ture of the well above the ground is subjected to damaging forces, including: valve means positioned in the well below said structure; said valve means being spring loaded to occupy a position permitting flow through the well; said valve means being exposed to the pressure of fluid in the well and movable responsive to said pressure into position to shut off said flow; means for subjecting said valve means to well fluid pressure counteracting the well pressure tending to move said valve whereby the spring load will maintain the valve open; and control means operable responsive to movement of the structure of the well above the ground for relieving the valve means of said counteracting well pressure whereby said valve means will be moved by the well pressure into said position.

21. Apparatus for protecting a flowing well against the loss of fluid products from a flow conduit at the top of the well in the event the structure of the well above the ground is subjected to potentially damaging forces, including: a flow conduit at the top of the well; subsurface valve means disposed in the well below said flow conduit including a body having a bore therein open to the well fluids, said body having a port leading from said bore through said body; a valve sleeve shiftable in opposite directions from an open to a closed position to permit and prevent fluid flow through said port to the top of the well; said valve sleeve having opposed fluid pressure responsive areas; one of said areas being exposed to fluid pressure in said bore for urging the sleeve to a closed position; means including a second conduit leading from said subsurface valve means to the top of the well and connected to the flow conduit aforesaid for exposing the other of said areas of said valve sleeve to well pressure to hold open said subsurface valve means; and control valve means at the .top of the well connected to one of said conduits and operable responsive to said forces above the ground for relieving said second conduit of well pressure, whereby said valve sleeve will be shifted by said fluid pressure in said well to a position closing said port.

22. Apparatus for protecting a flowing well against loss of fluid products from a flow conduit at the top of the well, including: a flow conduit at the top of the well; shiftable means at the top of the well arranged to move under heavy forces accidentally applied at the top of the well before such forces become eflective to damage the flow conduit at the top of the well and cause such loss of fluid products; fluid pressure operated valve means disposed in the well below said flow structure; said valve means including a body open to well fluids below the body and a passage communicating with said bore and extending through the body; a valve element shiftable to positions opening and closing said passage for permitting and preventing the flow of fluid products from the well; said valve element having a first fluid pressure responsive area subjected to pressure of fluid in said well to shift said element in a direction closing said passage; said valve element having a second fluid pressure responsive area; means extending from said valve means to the top of the well and connected to said flow conduit for subjecting said second fluid pressure responsive area of said valve element to fluid pressure derived from the well for holding said valve element in a position in which said passage is open; and control valve means connected to said shiftable means at the top of the well and operable by the latter upon the application of such potentially damaging forces to relieve said second fluid pressure responsive area of said fluid pressure derived from the well, whereby said valve means will be automatically closed.

23. Apparatus for protecting a flowing well against the loss of fluid products from a flow conduit at the top of the well, comprising: valve means disposed in the well below said flow conduit including a body open to well fluid below the body and having a passage extending through the body; a valve element shiftable to positions opening and closing said passage; said element having a first fluid pressure responsive area subjected to the pressure of fluid in said well for shifting said valve element to a position closing said passage; said element having a second fluid pressure responsive area; and means extending from said valve means and connected to said flow conduit for conducting fluid under pressure from the top of the well to said valve means so that well pressure is imposed on said second fluid pressure responsive area to prevent said valve means from closing, whereby upon relief of the well fluid pressure imposed on said second fluid pressure responsive area said valve means will be automatically closed.

24. A well tool including: a tubular body adapted to be positioned in a well conduit; means for sealing between said conduit and said body; means for supporting said body in said conduit; said body having a port above said sealing means for conducting fluid from within said body into said conduit; a valve associated with said body for opening and closing said port; means for shifting said valve in opposite directions to open and close said port including first and second surfaces responsive to fluid pressure; means including a tube leading from the top of the well for conducting fluid to said first surface to open said port; said second surface being exposed to well fluid pressure below said sealing means to close said port upon relief of the pressure applied to said first surface; and valve means in said tube at the top of the well for controlling the application of fluid pressure through said tube to said first surface to cause said valve to be held in a posi- 2% tion at which said port is open and to allow said valve to be moved to a position at which said port is closed.

25 A well tool including: a tubular body adapted to be positioned in a well conduit; means for sealing between said conduit and said body; means for supporting said body in said conduit; said body having a port above said sealing means for conducting fluid from within said body into said conduit; a valve associated with said body for opening and closing said port; means for shifting said valve in opposite directions to open and close said port including first and second surfaces responsive to fluid pressure; means including a tube leading from the top of the well for conducting fluid to said first surface to open said port; said second surface being exposed to well fluid pressure below said sealing means to close said port upon relief of the pressure applied to said first surface; and means at the top of the well for controlling the application of fluid pressure through said tube to said first surface to cause said valve to be held in a position at which said port is open and to allow said valve to be moved to a position at which said port is closed.

26. A well tool as defined in claim 24, wherein the means for controlling the application of fluid pressure through said tube comprises a valve.

27. A well tool as defined in claim 26, in which said valve is a manual valve.

28. A well tool as defined in claim 26, wherein said valve comprises trigger means operable responsive to a shock imposed on said means at the top of the well.

29. A well tool including: a tubular body adapted to be anchored in a well; packing means on the body operable for sealing against the wall of the well; anchoring means on the body operable to anchor the tool in the well; said body having a port above said packing means for conducting fluid from said body into the well above said body; a sleeve valve shiftably disposed in said body; means for shifting said sleeve valve in opposite directions to open and close said port including internal and external surfaces on said sleeve valve responsive to fluid pressure; said internal surface being exposed to well fluid pressure; means including a conduit leading from the top of the well for conducting well fluid pressure to said external valve sleeve surface; and means at the top of the well and connected with said conduit for controlling the application of well pressure through said conduit to said external sleeve valve surface to cause said port to be closed by said sleeve valve.

References Cited by the Examiner UNITED STATES PATENTS 2,963,089 12/60 Sizer 166--224X FOREIGN PATENTS 774,784 5/57 Great Britain.

CHARLES E. OCONNELL, Primary Examiner.

Claims

1. APPARATUS FOR PROTECTING A FLOWING WELL AGAINST THE LOSS OF FLUID PRODUCTS OF THE WELL FROM A CONDUIT AT THE TOP OF THE WELL, INCLUDING: MEANS AT THE TOP OF THE WELL ADAPTED TO BE MOVED BY FORCES WHICH IF SUSTAINED BY THE CONDUIT AT THE TOP OF THE WELL WOULD CAUSE SUCH LOSS; VALVE MEANS LOCATED IN THE WELL BELOW SAID FLOW STRUCTURE, SAID VALVE MEANS INCLUDING A BODY OPEN TO WELL FLUIDS THEREBELOW AND HAVING A PASSAGE LEADING TO THE WELL ABOVE THE VALVE MEANS FROM SAID BODY; A VALVE ELEMENT IN SAID BODY SHIFTABLE TO A POSITION CLOSING SAID PASSAGE TO CLOSE THE VALVE MEANS AND TO A POSITION SPACED FROM SAID PASSAGE