Packer valve arrangement

Abstract

A valve system for use in inflating packers mounted on mandrels is disclosed. The valve system uses one or more valves to permit, through the use of seals, the flow of fluid from the interior of a tubular mandrel to the interior of the inflatable packer when pressure applied in the mandrel exceeds at least a minimum pressure. In two embodiments, inflation of the packer beyond a given pressure is prevented. In all embodiments, the differential pressure across reciprocating seals is minimized through exposure of one or both sides, directly or indirectly, to the external pressure of the mandrel and packer.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to packer inflation systems and more particularly to the valves which control the inflation of packers.

2. Description of the Prior Art

The control of the inflation of well packers is important to obtain integrity between the packer and the well bore for purposes of working within the bore. It is known in the art to inflate packers by various mechanisms. See, for example, U.S. Pat. No. 3,503,445, issued Mar. 31, 1970, to K. L. Cochran et al. entitled "Well Control During Drilling Operations"; U.S. Pat. No. 3,351,349, issued Nov. 7, 1967, to D. V. Chenoweth, entitled "Hydraulically Expandable Well Packer"; U.S. Pat. No. 3,373,820, issued Mar. 19, 1968, to L. H. Robinson, Jr. et al, entitled "Apparatus for Drilling with a Gaseous Drilling Fluid".

In U.S. Pat. No. 3,437,142, issued Apr. 8, 1969, to George E. Conover, entitled "Inflatable Packer for External Use on Casing and Liners and Method of Use", there is disclosed an inflatable packer for external use on tubular members such as casings, liners, and the like. A valving arrangement is disclosed therein for containing fluid within the interior of the inflatable member after it has been inflated to prevent its return to the tubular member.

Arrangements of valving have been known in the prior art to prevent further communication between the interior of the tubular member and the interior of the inflatable element after the inflatable element has been inflated and set in a well bore. See, for example, U.S. Pat. No. 3,427,651; issued Feb. 11, 1969, to W. J. Bielstein et al, entitled "Well Control"; U.S. Pat. No. 3,542,127, issued Nov. 24, 1970, to Billy C. Malone, entitled "Reinforced Inflatable Packer with Expansible Back-up Skirts for End Portions"; U.S. Pat. No. 3,581,816, issued June 1, 1971, to Billy C. Malone, entitled "Permanent Set Inflatable Element"; U.S. Pat. No. 3,818,922, issued June 25, 1974, to Billy C. Malone, entitled "Safety Valve Arrangement for Controlling Communication Between the Interior and Exterior of a Tubular Member"; and U.S. Pat. No. 3,776,308, issued Dec. 4, 1973, to Billy C. Malone, entitled "Safety Valve Arrangement for Controlling Communication Between the Interior and Exterior of a Tubular Member".

Inflatable packers have also been used in other operations, such as sealing the annular space between a jacket and a piling. See for example U.S. Pat. No. 4,063,427, issued Dec. 20, 1977, to Erwin E. Hoffman, entitled "Seal Arrangement and Flow Control Means Therefor".

The seals that are used in valves, such as in Malone, are usually hardened rubber. Such rubber tends to extrude under extreme pressure differential across the rubber and cause friction between rubber and metal that adversely affects valve operation. None of the prior art, however, provides for mechanism for equalizing pressures across the seals of the valves used to inflate packers to prevent such extrusion.

SUMMARY OF THE INVENTION

The present invention utilizes a unique arrangement of sealing mechanisms in conjunction with a valve or valves to permit the inflation of an inflatable packer element while at the same time equalizing pressure around the rubber seals of the valve or valves to prevent distortion of the seals from undue high differential pressure, and the resulting friction.

The present invention, like the prior art, is constructed and arranged so that the valve or valves remain seated to prevent communication between the interior of a tubular member and the interior of an inflatable element carried on the exterior of the tubular member until at least a predetermined pressure has been reached. This reduces the possibility of premature inflation of the inflatable element by sudden pressure changes or pressure surges which may occur within the tubular member as the tubular member is being positioned within a well bore.

However, the valve arrangement of the inflation system of the present invention includes an appropriate arrangement of the valve structure to compensate for bore pressure to prevent extrusion from undue high differential pressures across the seals of certain rubber seals which must move in the valving operation.

memberthe prior art valve in FIG. 3.

, forming a substantial pocket chamberBore A bore 301, a first counterbore 302 and a second counterbore 304, counterbores are the single valve pocket 300. Counterbores 302, and 304 are separated by stop wings 306, and the counterbores are formed by drilling or other suitable operation in the pocket 300. Stop The stop wings 306 form an upwardly facing shoulder 316 with the counter bore 302 and a downwardly, outwardly facing shoulder 307 with the enlarged counterbore 304. Passageways 54, 303, 137 and 236 are formed in the valve collar 14" to be in communication to interior bore 21 of the pipe member 10 11, the external surface of valve collar 14" on the outside of tubular element the packer 10, the fluid channel 20 and the interior of packer the packing element 30, respectively, and to the valve pocket 300. The A valve element 318, which is inserted into the valve pocket 300, includes a first valve body member 320 having an upper surface 373 and a lower surface 346 located in the second counterbore 304, a spring 322 located in a bore first counterbore 302, and a second valve body element member 324 having upper surface 372 and located in the bore 301 and a lower surface 374 located in bore 301 and the counterbore 302 in the initial assembled position. Passageway The passageway 303 has a lower surface 315 substantially coplaner with the spring 322 in the initial assembled position. First The first valve body member 320 includes an enlarged valve portion 330 having a groove 332 formed thereabout for reception of a seal 334 therein. Seal The seal 334 is sized to sealingly engage the sides wall of the counterbore 304 and the bottom surface 336 of the groove 332. Stem A valve stem 338, on the valve body member is of smaller diameter than the enlarged valve portion 330, and extends from the enlarged valve portion 330 longitudinally to the end of the counterbore 304 approximately coplaner with shoulders the shoulder 316. The diameter of the valve stem 338 is substantially less than the diameter of the valve body portion 330 and forms a shoulder 340 at the interface between the valve steam 338 and the valve body portion 330. Stop wings 342 extend from stem 338. Stop wings 342 extend laterally from the valve stem 338 and are appropriately positioned along the length of the valve stem 338 to perform as set out below approximately midway along the length of the valve stem 338. The longitudinal placement of the stop wings 342 is determined by the length dimension of the shoulder 307. Stop The stop wings 342 must be sufficiently displaced from the shoulder 340 along the surface of the valve stem 338 to permit the stop wings 342 to extend above the shoulder 316 when the shoulder 340 meets the lower downwardly outwardly extending surface 307. A first shear pin 344, or collet, or other suitable mechanism for prevention of reciprocation, extends through the surface of the valve collar 14" and into the base 346 of the valve portion 330 and releasably holds the valve portion 330 in its initial position.

Spring 322 is of any suitable material having an inner diameter larger than the diameter of the valve stem 338 and having a collapsed length substantially equal to the distance from the shoulder 316 to the lower surface 315 of the passageway 314 303.

Upper The upper valve element or member 324 includes a valve base portion 350 having a diameter greater than the diameter of the bore 301. Element The upper valve element 324 is reduced in size along most of the portion extending away from lower valve element 322 the valve base portion 350 to form a valve stem portion 352 having a smaller diameter than the bore 301 with a shoulder 354 formed at the juncture of the valve stem portion 352 and the valve base portion 350. Two grooves 356, 358 are formed along the circumference of the valve stem portion 352 and spaced such that circumferential seals 360, 362 may be fit therein and sealingly engaging engage the walls of the bore 301 and the walls 364, 366 respectively of the valve stem portion 352. Grooves 356, 358 are spaced apart sufficiently so that the seals 362, 366 engage the walls on either side of the passage 137 when the shoulder 354 abuts the shoulder 368 formed between the counterbore 302 and the bore 301. A shear pin 369, or collet, or other suitable mechanism for prevention of reciprocation, extends through the surface of the valve collar 14" and into a bore 370 formed in the valve stem portion 352 upon initial assembly and releasably holds the valve stem portion 352 in its initial position.

Referring to FIGS. 9a-9c, in operation the pressure from the internal portion of tubular member 10 bore 21 of the pipe member 11 is applied at through the passageway 54 against the surface 372 of the upper member valve body element 324. At the same time, pressure in the borehole external to the valve collar 14" is applied via passageway 303 to the areas defined by seals 362 and 334 in the pocket. Pressure in the borehole external to the valve collar 14" is applied via the packing element 30 and the passageway 236 to the other side of seal 334 and is applied via the packing element 30 and to the passageway 137 to the portion of the bore 301 located between the seals 360 and 362. When this the pressure within tubular pipe member 11 is sufficient to overcome the shear strength of the shear pin 369, the shear pin 369 shears (FIG. 9b) permitting the pressure acting on the surface 372 to move member the second valve body member 324 longitudinally towards lower second valve portion body member 320 and to compress the spring 322. Accordingly, the valve seal 360 no longer prevents flow of fluid from the passageway 54 to the passageway 137, and fluid then flows to passageway 137 from passageway 54. Fluid in passageway 137 flows into the channel 20 and thence to the interior of packer the packing element 30 and inflates packer the packing element 30. Fluid communication with the interior of the packer packing element 30 is accomplished through the passageway 236 and permits pressure to build in passageway 236. When equal to the pressure within the packing element 30. It will be noted that the pressure area across the seal 334 is larger than the pressure area across the seal 362 and thus when the fluid in the passageway 236 has reached a predetermined pressure, greater than or equal to the pressure in the passageway 303, as determined by the shear force of the shear pin 344 and the surface area of seal 334, the shear pin 344 shears (FIG. 9c) forcing lower the second valve body member 320 to rise or move and the end surface 373 of 171 upper the second valve body member 320 to abut the surface 374 of upper first valve body member 324. Because the surface area of the surface 346 is substantially greater than the surface area of the surface 372, the pressure in the passageway 236 acting on the surface 346 will eventually force both lower the second valve body member 320 and upper the first valve body member 324 to move through their respective pockets bores until the shoulder 340 on the second valve body member 320 contacts the inclined surface 307. At this point, the seals 360, 362 on the second valve body member 320 would be again spaced around or to either side of the passageway 137 to prevent further flow of fluid into the the passageway 137 from passageway 54 thereby retaining the inflation of pressure in the packers packing element 30. Should there by be a small loss in pressure in the passageway 236 against surface 346, the optional stop wings 342 (which can be optional) would prevent lower the valve body member 320 and upper the valve element body member 324 from moving sufficiently to again permit flow between the passageways 54 and 137.

Although the system described in detail above is most satisfactory and preferred, many variations in structure and method are possible. For example, wings 342 may be eliminated. Also, the members may be made of any material suitable for the environment. Further, reciprocating member or upper valve element body member 324 may be split horizontally so that the member has two pieces, each piece having one seal and the lower seal being of a poppet type.

The above are examples of the possible changes or variations.

Because many varying and different embodiments may be made within the scope of the inventive concept herein taught and because modifications may be made in accordance with the descriptive requirements of the law, it should be understood that the details herein are to be interpreted as illustrative and not in a limiting sense.

Claims

1. In a tubular system having

a hollow tubular mandrel;

a packer an inflatable packing element attached to the mandrel at one end;

a valve collar mounted on the other end of the mandrel, the other end of the packer packing element being attached to the valve collar and the valve collar being in fluid communication with the packer packing element by a passage means and the valve collar also being in fluid communication with the interior bore and the exterior of the mandrel;

a valve system mounted on the mandrel in the valve collar, the valve system being in fluid communication with the packer packing element and the interior bore and the exterior of the mandrel, the valve system including at least one valve means with at least one reciprocating member valve element and a stop means for preventing reciprocation of the reciprocating member valve element prior to the application of at least a predetermined pressure difference to the reciprocating member valve element, the reciprocating member valve element being located at one end of in one position in the passage one valve means when the stop means prevents reciprocation, the reciprocating member valve element having at least two seals thereon for preventing the flow of fluid from either side of the reciprocating member around the member seals to the passage means;

the improvement comprising:

first means independent of the seals for permitting the flow of fluid from the interior bore of the mandrel to one side of one seal of on the reciprocating member valve element; and

second means independent of the seals for permitting the flow of fluid from the exterior of the mandrel to oppositely facing surface side of the other seal of on the reciprocating member valve element; and

third means independent of the seals for equalizing the pressure on the other side of each of permitting the flow of fluid to a location between the seals for equalizing the pressure across the seals to substantially that of the pressure at the exterior of the mandrel and to the pressure in the interior bore of the mandrel.

2. A tubular system for use in packing off a well bore, comprising:

a hollow tubular mandrel;

a packer attached to said mandrel at one end of said mandrel;

a valve collar mounted on the other end of said mandrel, the other end of said packer being attached to said collar and having a passageway therethrough, and said collar being in fluid communication with said packer and the interior and exterior of said mandrel by said passageway;

said passageway having enlarged portions in said collar;

a valve system mounted in said enlarged portions, said valve system including three valves;

the first of said valves being mounted in the first of said portions and having a reciprocating member and a stop means for preventing reciprocation of said reciprocating member prior to the application of at least a predetermined difference in pressure between one side of said reciprocating member and the other side, said reciprocating member being located at one end of a first part of said passageway when said stop means prevents reciprocation and having at least two seals thereon for preventing the flow of fluid from either end of said reciprocating member around the member to said first passageway part;

said first valve being in fluid communication with a second part of said passageway in fluid communication with said interior of said mandrel on one side of said reciprocating member;

said first valve being in fluid communication with said exterior of said mandrel on the other side of said reciprocating member; and

the second of said valves having check means for permitting the flow of fluid from said exterior of said mandrel to said first part of said passageway when the pressure in said mandrel exceeds the pressure in said second portion.

3. The system of claim 2, wherein said second portion includes a first bore opening to said exterior of said mandrel and said second valve is located in said first bore.

4. The system of claim 3, wherein said second valve uncludes:

a head adapted to connect to said first bore;

a seal mounted on said head and sealingly engaging the walls of said first bore and said head; and

said check means is mounted in said head.

5. The system of claims 2, 3 or 4 wherein the remainder of said second portion is filled with a liquid.

6. The system of claims 1, 2, 3 or 4 wherein;

said third valve is mounted in a third of said portions, said third portion being in fluid communication with said exterior of said mandrel and a third part of said passageway in fluid communication between said second portion and said third portion and a fourth part of said passageway in fluid communication with said packer;

said third valve including

first seal means for preventing fluid communication between said third portion and said exterior of said mandrel, and

second seal means for preventing fluid communication between said third part and said fourth part when the pressure in said fourth part is greater

than the pressure in said third part. 7. A tubular system for use in packing off a well bore, comprising:

a hollow tubular mandrel;

a packer an inflatable packing element attached to said mandrel at one end of said mandrel having an interior portion separated from said mandrel so as to receive inflating fluid and an inlet means to admit fluid to said interior portion;

a valve collar mounted on other end of said mandrel and having a passageway means therethrough, the other end of said packer packing element being attached to said valve collar, and said passageway means in said valve collar being in fluid communication with said inlet to said packer means of said packing element, with said interior portion of said packer packing element and with the interior bore and the exterior of said mandrel by said passageway;

a valve pocket system in said passageway means having enlarged portions in said valve collar, including

a first portion valve pocket means in fluid communication with a first part of said passageway in fluid communication with the interior bore of said mandrel,

a second portion valve pocket means in fluid communication with said external part the exterior of said mandrel and a second part of said passageway in fluid communication with said first portion said first valve pocket means, and

a third portion valve pocket means in fluid communication with a third part of said passageway in fluid communication with said second portion, said third portion said second valve pocket means and also being in having separate fluid communication with a fourth part of said passageway in fluid communication with said interior at said packer and a fifth part of said passageway in fluid communication with said inlet to said packer paths to said inlet means and to the interior of said packing element;

a valve system mounted in said enlarged portions;

said valve system including three valves;

valve means in said first and third valve pocket means and operable in response to pressure in said passageway means;

the second of said valves being mounted in said second portion and having valve means in said second valve pocket means for controlling the flow of fluid from the interior bore of said tubular mandrel to said inlet means including a shear valve member in said second valve pocket means, said shear valve member being a reciprocating member movable between a first and second position and a stop shear means for preventing reciprocation of said reciprocating member in said first position prior to the application of at least a predetermined difference in pressure between one side of said reciprocating member and the other side of said reciprocating member, said reciprocating member being located at one end of said second part second valve pocket means when said stop shear means prevents reciprocation and having at least two seals thereon for preventing the flow of fluid from either end of said reciprocating member around said reciprocating member to said third part pocket

valve means. 8. The system of claim 7 wherein:

said second valve seals on said shear valve member are mounted to avoid prevention of permit flow between said second portion and said third portion through said third part when said stop means permits reciprocation first valve pocket means and said third valve pocket means when said reciprocating member is in

said second position. 9. The system of claims 7 or 8 wherein:

said valve means disposed in said first valve pocket means include:

a reciprocating valve member movable between a first and second position and normally resiliently biased to the first position,

said first valve is mounted in said first portion,

said first valve including

first seal means for preventing fluid communication between said first portion and said second valve pocket means and the exterior of said mandrel, in said first position; and

second seal means on said resiliently biased reciprocating valve member for preventing fluid communication between said first part and said second part the interior bore of said mandrel and said second valve pocket means when the pressure in said second part first valve pocket means is greater than the pressure in said first part the interior of the

mandrel. 10. The system of claims 7 or 8 wherein:

said third portion is in fluid communication with said exterior of said mandrel;

said third valve is mounted in said third portion and said valve means disposed in said third valve pocket means includes a second reciprocating valve member and a third reciprocating member connected by a stem and a second movable between a first and second position, stop means in said third valve pocket means for preventing reciprocation of said reciprocating members valve member prior to the application of at least a predetermined pressure difference between one side of said second reciprocating valve member and the oppositely facing side of said third reciprocating valve member, said second reciprocating valve member having two seals thereon and being positioned in said third portion in a spaced apart relationship so that at least one of said seals prevents fluid flow between said fourth part and said third portion third valve pocket means and said communication path to the interior of said packing element when said stop means prevents reciprocation in said first position;

said third reciprocating valve member includes in said third valve pocket means having third seal means along its length for preventing fluid communication between a portion of said third portion and said said third valve pocket means and the exterior of said mandrel; and

said first and second seals thereon being spaced for preventing the flow of fluid flow from either side of said second reciprocating member to said third part the inlet means or the interior of the packing means after said second stop means no longer prevents reciprocation, releases said reciprocating valve member in said third valve pocket means and said reciprocating valve member moves to said second position said seals and reciprocating valve member in said third valve pocket means being positioned to permit flow from said third part to said fifth part about said stem second valve pocket means to said inlet means when said second reciprocating valve member in said third valve pocket means is prevented from reciprocating by said second stop

means in said first position. 11. The system of claim 10 wherein there is further included a small, relief passage means between said two first and second seals of said second reciprocating valve member and one of the ends of said second reciprocating

valve member. 12. A tubular member An inflatable packer for use in a bore, comprising:

a tubular mandrel;

a packer an inflatable packing element attached to said mandrel at one end of said mandrel and having an interior portion separated from said mandrel;

a valve collar mounted on the other end of said mandrel and having a passageway therethrough, the other end of said packer being attached to said valve collar, and said valve collar being in having means providing a fluid communication path with said interior of said packer by a passage packing element and with the interior bore and the exterior of said mandrel;

said passage fluid communication path having at least one enlarged portion forming a part valve pocket means in said valve collar;

a valve system mounted in said enlarged portion, said valve system being valve element means in said valve pocket means in fluid communication with the interior of said packer packing element and the interior bore and the exterior of said mandrel; and including means responsive to a differential pressure between the pressure exterior to the valve collar and the pressure within the packing element for closing off fluid flow in said communication path to said packing element;

said valve collar being adapted to be inserted at attached to the end of said mandrel that is last to enter the bore.

13. A tubular system for use in packing off a well bore, comprising:

a hollow tubular mandrel;

a packer attached to said mandrel at one end of said mandrel having an interior portion separated from said mandrel and an inlet to said interior portion;

a valve holder mounted on other end of said mandrel and having a passageway therethrough, the other end of said packer being attached to said valve holder, and said valve holder being in fluid communication with said inlet to said packer and the interior and exterior of said mandrel by said passageway;

said passageway having an enlarged portion in said valve holder, said portion being in fluid communication with:

a first part of said passageway in fluid communication with interior of said mandrel,

said external part of said mandrel, and

a second part of said passageway in fluid communication with said inlet to said packer;

a valve system mounted in said enlarged portion, said valve system including at least one valve, said valve being mounted in said portion and having a reciprocating member and a stop means for preventing reciprocation of said reciprocating member prior to the application of at least a predetermined difference in pressure between one side of said reciprocating member and the other side, said reciprocating member being located at one end of said portion when said stop means prevents reciprocation and having at least two seals thereon for preventing the flow of fluid from either end of said reciprocating member around said member to said second part;

each of said seals being exposed on one side thereof to fluid from said

second part. 14. An inflatable well packer for use in a well bore traversing earth formations where the well packer has a tubular mandrel, an inflatable packer element on said tubular mandrel with one end of the packer element attached to the mandrel and a valve collar means attached to the other end of the packer element and mandrel,

the improvement comprising:

valve means and passage means in said valve collar means for selectively admitting fluid from the interior bore of the tubular mandrel to the interior space between said packer element and said tubular mandrel, said valve means including a first valve having spaced apart seal means on an elongated first valve element slidably received in said valve collar means for movement between first and second positions, said seal means in a first position of said valve element straddling a section of the passage means leading to said interior space between said packer element and said tubular mandrel,

release means for releasably retaining said first valve element in said first position and releasable upon the application of predetermined pressure differential across said seal means to move said valve element to said second position,

said valve element on one side of said seal means having access to the pressure exterior of the valve collar and having access on the other side of said seal means to the pressure in a portion of the passage means leading to the interior bore of said tubular mandrel so as to pressure balance said first valve element across said seal means between the interior bore of the tubular mandrel and the exterior of the valve collar means. 15. An inflatable well packer for use in a well bore which traverses earth formations wherein the lower end of such well packer is intended to enter the well bore first, and including

a tubular mandrel adapted for coupling a string of pipe,

an inflatable packer element disposed on said tubular mandrel and attached at its lower end to said tubular mandrel in a fluid tight relationship,

valve collar means attached to the upper end of said packer element and said tubular mandrel so as to have access to the pressure in the well bore above the inflatable packer element,

said valve collar means including at least one releasable valve means and passage means where said releasable valve means is in fluid communication with the interior bore of said tubular mandrel, the interior of the inflatable packer means and the exterior of said valve collar means above said packer element, said releasable valve means being normally retained in a first position and being releasable to a second position with respect to said passage means upon the application of a predetermined pressure differential between the fluid in the interior of the packer element and the fluid at the exterior of the valve collar means to move said releasable valve means between said first and second positions. 16. The well packer as defined in claim 15 where said releasable valve means includes a shear pin and movable valve element.