Valve for Hydraulic Setting Packer Setting Tool and Method of Setting a Hydraulically Settable Packer Therewith

This invention is related to oil well packers which are hydraulically set and which include a tubing motion compensation feature to prevent motion of the tubing from interferring with the packer after it has been set yet at the same time permit fluid communication through the packer mandrel via the well tubing and the packer setting tool.

The prior art hydraulically set packers are constructed with the well tubing rigidly attached to the packer mandrel so that when the packer is set, the tubing is rigidly secured to the packer. Practice has shown this to be undesirable in some circumstances because motion of the tubing within the well bore can damage the packer components as well as destroy the fluid tight seal provided by the packer. This motion of the well tubing above the packer can be due to normal or routine well servicing operations carried out at the ground level or pumping and pressurization operations carried out where the tubing is involved. Because of this tubing motion, the motion compensation is highly desirable within the fluid connection between the packer and the well tubing. While this motion compensation can be accomplished by numerous constructions, it is most desirable to have this motion compensation combined with the ability to pump fluid through the packer setting tool for setting the packer as well as achieve the motion compensation.

An embodiment of this invention includes a hydraulic packer setting tool which is attached to the well tubing and positioned within the hydraulically settable well packer. The tool contains a valve which is open when the packer is set yet which closes when the setting tool is moved upward a predetermined amount so an accompanying seal nipple will maintain a fluid connection between the well tubing and the packer mandrel bore and compensate for vertical relative motion between the well packer and the tubing.

One object of this invention is to provide a hydraulic packer setting tool which overcomes the aforementioned disadvantages of the prior art devices.

Still, one other object of this invention is to provide a fluid flow control valve for a hydraulic packer setting tool which is opened and closed by motion into and out of the well packer.

Still, another object of this invention is to provide a hydraulic packer setting tool which functions to achieve setting of the packer and which provides for motion compensation between the packer and the tubing attached to the setting tool thus permitting fluid communication through the packer mandrel bore without fluid leakage into the annular cavity of fluid chamber above the packer within the casing around the tubing.

Various other objects, advantages and features of this invention will become apparent to those skilled in the art from the following discussion, taken in conjunction with the accompanying drawings, in which:

FIG. 1A, B and C comprise a partial cross-sectional elevation view of a hydraulic setting packer in the set position and a setting tool having the valve mechanism of this invention;

FIG. 2 is a partial cross-sectional elevation view of the upper portion of the packer shown in FIG. 1 and the setting tool in a condition wherein the packer is set, the setting tool raised, the valve open, and the upper end of the valve actuator collet engaged to initiate closing of the valve;

FIG. 3 is a view similar to FIG. 2 with the setting tool displaced further upward and the valve in the closed position;

FIG. 4 is a view similar to FIG. 3 with the setting tool displaced further upward and the valve positioned within the bore of the top connection;

FIG. 5 is a partial cross-sectional elevation view of the valve nipple alone with the valve member in the open position; and

FIG. 6 is an enlarged elevation view of the valve sleeve with the collet latching surfaces modified.

The following is a discussion and a description of preferred specific embodiments of the structure of this invention, such being made with reference to the drawings, whereupon the same reference numerals are used to indicate the same or similar parts and/or structure. It is to be understood that such discussion and description is not to unduly limit the scope of the invention.

Referring now to FIG. 1, the hydraulically set well packer 10 is illustrated in this partial cross-sectional view in a set position with the setting tool in the appropriate position for setting the packer. The packer assembly generally comprises several telescopically constructed subassemblies generally consisting of an inner mandrel assembly, a packer mandrel 12, a hydraulic cylinder assembly, an upper slip assembly, an upper packer assembly, a lower packer assembly, and a lower slip assembly. The hydraulic setting tool or telescopic tubular assembly 14 is slidably mounted within the bore of packer mandrel 12 and secured to the packer while it is run into the well and positioned for setting of the packer. The hydraulic setting tool has the valve assembly of this invention mounted therewith and positioned within the packer.

The inner mandrel assembly generally comprises an elongated tubular cylindrical packer mandrel 12 having threadedly attached at the top thereof a top connection sleeve 16. Top connection sleeve 16 has latch teeth 18 on its exterior thereof and threads 20 on its upper interior. A plurality of flow ports 22 (or setting ports) extend through packer mandrel 12 near the upper end thereof below the top connection sleeve 16. An annular abutment shoulder 24 is formed externally around the outer wall of mandrel 12 substantially below flow or setting ports 22. At the lower end of mandrel 12, a bottom collet sleeve 26 is threadedly attached thereto. Bottom collet sleeve 26 has a plurality of collet fingers 28 extending downwardly therefrom. Collet fingers 28 are formed by longitudinal slots through the wall of the bottom portion of collet sleeve 26. Collet fingers 28 have external threads on their lower end portion. Collet fingers 28 are maintained in an outwardly expanded direction by the location of a retrieval mandrel 30 located slidably within sleeve 26.

A tubular hydraulic cylinder assembly is located on the upper end portion of the packer and it has an upper slip abutment collar 36 on its lower end above the upper slip or tubular gripping member 32. The tubular hydraulic cylinder assembly has a main hydraulic cylinder 34 extending upward from collar 36 which has a guide 38 mounted at the top thereof. A spring collet sleeve 40 with teeth on the interior thereof is held between guide 38 and hydraulic cylinder 34. Spring collet sleeve 40 functions as a take-up latch assembly to secure the packer when the packer has been set. An annular hydraulic chamber 42 is formed between hydraulic cylinder 34, packer mandrel 12, and the bottom of a piston sleeve 46. Piston sleeve 46 is threadedly attached to the top of mandrel 12 and hydraulic cylinder 34 is slidably mounted on packer mandrel 12.

The upper slip assembly is located between slip abutment collar 36 and the upper packer assembly. Slip abutment collar 36 has a plurality of bolts 48 extending therethrough into slip carrier sleeve 50. A lock ring 52 is located between collar 36 and sleeve 50 and engages a peripheral groove formed in sleeve 50. An annular rubber spring 54 is held and trapped between lock ring 52 and the lower end of hydraulic cylinder 34. An upper unitary tubular gripping member, or slip, 32 is shearably mounted to carrier sleeve 50 by a pair of laterally opposed shear pins 58. This mounting of upper slip 32 permits rotation into the set position freely yet allows pins 58 to shear during retrieving of the packer. Upper slip 32 has external gripping teeth formed at diametrically opposed ends thereof for grippingly engaging the interior of the well casing. A leaf spring 60 is attached to upper slip 32 and abuts carrier sleeve 50 to continuously bias upper slip 32 to a radially inward non-gripping orientation. Upper slip 32 has a slot with an upper abutment shoulder formed on one side thereof. An unsetting lug 62 is formed on carrier sleeve 50 and extends radially outward inside of this slot within upper slip 32. An upper abutment shoulder in this slot is arranged to be contacted by the upper portion of unsetting lug 62 for pivoting upper slip 32 to a non-gripping position upon unsetting or release of the packer. During the unsetting motion of the packer, laterally opposed shear pins 58 are sheared, then the upper slip 32 is rotated and displaced upward relative to the stationary portions of the packer.

The upper packer assembly comprises an upper guide ring 64 attached to a guide cylinder 66 which is in turn connected to an upper packer head 68 around one end of a cylindrical packer sleeve 70. A plurality of elastomeric packer elements 72 are separated by metallic packer rings 74 located concentrically and slidably on packer sleeve 70. A guide pin 76 is threadedly engaged in mandrel 12 and projects radially outward into a slot 78 formed through the wall of sleeve 66 and in longitudinal axial alignment with mandrel 12. Slot 78 and guide pin 76 prevent relative rotation of the associated members of the packer when in service. The lower packer assembly generally consists of a lower packer head 80 slidably mounted on sleeve 70 and prevented from downward movement off of this sleeve by abutment with a radially outwardly extending annular shoulder formed near the bottom of the sleeve. Lower packer head 80 is in sliding abutment with the lower most packer element 72 and it has threadedly attached to the bottom thereof a lower spacer 82 with a plurality of ports 84 formed through the wall thereof. The bottom of this lower packer assembly is made up of a bottom ring 86 threadedly connected to spacer 82 and having an upward facing inner abutment shoulder 88 projecting inwardly for limiting abutment against slide limit ring 90. Slide limit ring 90 is mounted in an external groove around mandrel 12. A second upward facing abutment shoulder 92 is formed near the top of ring 86 for abutment with the bottom of packer sleeve 70.

The lower slip assembly has a bottom connector 94 at the lower end of the packer with a guide cylinder 96 through the mid-portion thereof and an adapter ring 98 at the upper end thereof. Threadedly attached to the top of adapter ring 98 is a slip control ring 100 which is connected by a plurality of shear pins 102 to a lower slip carrier sleeve, or lead in sleeve, 104. A guide pin 106 is threadedly engaged in the upper portion of collet sleeve 26 and projects radially outward into an elongated guide slot 108 longitudinally formed in the wall of guide cylinder 96. A rubber spring 110 is located in resilient abutting arrangement between adapter ring 98 and the bottom of carrier sleeve 104. A lower tubular gripping member, or slip, 112 is pivotally attached to carrier sleeve 104 by a pair of laterally opposed pins 114. Lower slip 112 is generally similar in construction to upper slip 32 but it is oriented in an invert position to oppose downward movement of the packer when set.

The hydraulic setting tool comprises an upper hydraulic mandrel 116, or latch seal nipple, threadedly connected to a lower hydraulic mandrel, or seal nipple, 118 by a valve collar or nipple assembly indicated generally at 120. The upper end of upper hydraulic mandrel 116 is threadedly connected by a collar 122 to the bottom of the tubing string. A plurality of external packing seals 124 are provided in a spaced relation on hydraulic mandrel 116 and on seal nipple 118. A port 126 is provided transversely through a midportion of valve collar assembly 120 to permit fluid to flow from the interior of the well tubing into the hydraulic setting cylinder assembly of the packer. The hydraulic setting tool extends in sealing engagement through piston sleeve 46 into packer mandrel 12. An elongated extension tube 128 is threadedly connected to the lower end of lower mandrel 118 and extends downward through the bottom end of the well packer. Preferably, a retrieving tool (not shown) is attached at the lower end of extension tube 128 for engagement with retrieval mandrel 30 when it is desired to unset or release the packer. Discussion of this retrieving tool and its operation is not pertinent here as it does not effect the operation or structure of this invention.

Attachment between hydraulic setting tool 14 and the packer which locks these members together for running into the well and positioning of the packer is accomplished by a locking device at the upper end of the packer. A locking sleeve 130 is secured to upper mandrel 116 by an abutment collar 132. Locking sleeve 130 is segmented and biased outward within abutment collar 132 by its own spring force. Abutment collar 132 is threadedly attached to upper mandrel 116, extends downward over the upper portion of locking sleeve 130 and abuts the upper end of top connection 16 when the packer is positioned for running into the well. The lower portion of locking sleeve 130 is threaded externally to mate with internal threads 20 at the upper end of top connection 16. The threads on locking sleeve 130 and the threads 20 are left handed so that rotation of the well tubing and attached upper mandrel 116 to the right will remove locking sleeve 130 from the packer and thus allow longitudinal sliding motion between the packer and the latch seal nipple. These threads are also formed as latch type threads which, along with the segmented construction of locking collar 132, will permit locking collar 132 to be stabbed into the upper portion of top connection 16 to secure the latch seal nipple and the packer.

FIG. 5 shows valve collar assembly 120 in an enlarged view with the valve thereof in the opened position. Valve collar assembly 120 is a nipple with an internally threaded upper end portion and an externally threaded lower end portion in a bore 134 therethrough. A valve nipple port 126 connects bore 134 with the exterior of the nipple. The valve member is a sleeve (or valve sleeve) 136 slidably mounted around a cylindrical exterior surface 138 on the nipple above and below port 126. Cylindrical surface 138 extends over a major portion of the nipple. Valve sleeve 136 slides longitudinally to cover and uncover port 126 to close and open the valve. The interior of valve sleeve 136 is provided with a pair of spaced apart O-rings 137 and 139 at the respective upper and lower mid-portions thereof. These O-rings are retained in annular grooves around the interior of the sleeve and seal on opposite sides of port 126 when the valve is closed. The exterior of the valve collar assembly is provided with a latching recess 140 around the lower end of cylindrical exterior surface 138 and above the lower exterior threads. Above cylindrical exterior surface 138 is a longitudinally elongated recess 142 around the nipple which terminates at a radially outwardly disposed and downwardly facing shoulder 144. Shoulder 144 extends radially outward beyond the radial dimension of surface 138.

Valve member 136 has an upper and lower actuator attached thereto which cooperatively engage recess 140 in the valve nipple and an internal recess 146 within the bore of top connection 16 to effect displacement of valve member 136 on the valve nipple during motion of the latch seal nipple unto and out of the packer. The valve lower actuator assembly includes a plurality of lower collet fingers 148 which extend downwardly from valve sleeve 136 in a natural unbiased condition around the inner portion of the sleeve. Collet fingers 156 are a segmented cylindrical extension of valve sleeve 136. The lower end portion of collet fingers 148 define a radially inwardly extending enlargement 150 of the collet. The major portion of lower collet fingers 148 lie adjacent to nipple cylindrical exterior surface 138 when the valve is closed. This arrangement biases lower collet fingers 148 inward in order to maintain contact between the radially inner portion of enlargement 150 and exterior surface 138 when the valve member is in the open position as shown in FIG. 5. Enlargements 150 have tapered latching surfaces 152 and 154 on upper and lower inner sides thereof which are inclined to correspond with the inclined sides of lower recess 140. Relative to a geometric plane lying perpendicular to the longitudinal axis of the valve nipple latching surface 152 can be inclined downward at an angle of between about 20.degree. to about 40.degree. from the elongated portion of lower collet finger 148 when it is in the unbiased position; and latching surface 154 is inclined upward from upper collet finger 156 at an angle of between about 50.degree. to about 70.degree.. When the valve is closed, enlargement 150 rests within lower recess 140 with inclined sides 152 and 154 thereof adjacent to associated sides of the recess.

The upper valve actuator includes a plurality of upper collet fingers 156 extending upward from valve member 136 in a cylindrical and naturally unbiased condition around the outer portion of the valve member. The collet fingers 156 are a segmented cylindrical extension of sleeve 136 and have a radially outwardly extending enlargement 158 at the upper end portion thereof with inclined latching surfaces 160 and 162 on upper and lower exposed portions of this enlargement. The interior of upper collet fingers 156 is spaced radially outward from the bottom of nipple recess 142 and from the interior of valve sleeve 136 as shown in FIG. 5. When valve collar assembly 120 is in packer mandrel 12 and some portions of top connection 16 upper collet fingers 156 are deformed inward because the exterior of enlarged portion 158 rides on the interior of the mandrel or the top connection depending upon its location. The upper end of upper collet fingers 156 rests against downwardly facing nipple shoulder 144 when the valve is in this position thereby limiting upward motion of the valve member. Latching surface 160 is inclined at a substantially steeper angle, relative to a geometric plane lying perpendicular to the longitudinal axis of the valve nipple, than lower latching surface 162. Relative to this geometric plane, latching surface 162 can be inclined upward at an angle of between about 50.degree. to about 70.degree..

At this point, it is to be noted that the relative angular relation of surfaces 152 and 162 has a bearing upon the latching and releasing action of the collet fingers. The latching and releasing action of the collet fingers is determined by their ability to grip in their associated recesses and this ability substantially depends upon the angles of surfaces 152 and 162 and corresponding surfaces in their associated recesses as well as tension or biasing forces acting on the collet fingers. Due to the structural attachment and placement of the collet fingers on valve sleeve 136, this factor remains essentially constant. The inclination of the frustoconically shaped latching surfaces 152, 162 and the corresponding surfaces in recesses 140 and 146 can be changed by machining of the respective parts. Selecting the angular orientation of surfaces 152, 162 and the associated recess surfaces as noted above will cause the valve sleeve to remain open after it is manually arranged in the open position before the packer is assembled and while the assembly is inserted into the packer and then closed upon subsequent withdrawal from the packer. This selection will not permit the valve to reopen even if it is reinserted into the packer after it has been withdrawn because opening of the valve must be done manually after it is removed from a well. Another selection of these parameters for opening and closing the valve appears following the description of operation of the valve assembly.

With the packer, seal nipple and hydraulic setting tool 14 in position as shown in FIG. 1, the valve collar assembly 120 is positioned as it appears in FIG. 5 with the valve being open to permit fluid flow from the well tubing through the latch seal nipple bore, valve nipple bore 134, valve nipple port 126, around the exterior of valve sleeve 136, through setting port 22 and into piston chamber 42. This fluid connection routes pressurized fluid from the well tubing above the packer to the packer setting mechanism and sets the packer within the well casing at the desired position. In order to provide an increase of fluid pressure inside the well tubing, a temporary blockage is created below port 126. This temporary blockage can be created by an expendable ball and seat or a wire line settable and retrievable plug either of which are commonly used in oil well hydraulically settable tools and will function adequately in this apparatus. Once the packer is set, then it is desirable to raise the well tubing so the sliding seal connection between the latch seal nipple and the interior of the packer mandrel will maintain the fluid connection and the unit will compensate for motion of the tubing relative to the stationary packer. This disconnection of the latch seal nipple from the packer is accomplished by rotating the well tubing in the right hand direction thereby unthreading the left hand threads of locking sleeve or collar 130 and top connection 16. When this is done, the tubing is raised vertically which pulls the latch seal nipple upward relative to the packer and thereby activates the valve actuator mechanism to close the valve. As the latch seal nipple moves upward from the position shown in FIG. 1, valve member 136 remains stationary on the valve nipple due to the friction of lower collet fingers 148 and nipple cylindrical exterior surface 138. When the latch seal nipple reaches a position shown in FIG. 2, upper collet fingers 156 are displaced radially outward into top connection recess 146 with enlarged portion 158 of upper collet fingers 156 extending into this recess. The upper collet finger upper latching surface 160 abuts the upper side of recess 146 and stops relative motion of valve sleeve 136 in top connection 16 as the latch seal nipple continues upward. The inclination of upper collet upper latching surface 160 is selected to create a binding force between top connection 16 and that collet which is sufficient to keep the valve sleeve in place against friction of the lower collet fingers and O-rings 137 and 139 sliding on nipple exterior surface 138. This stopping of relative motion causes valve sleeve 136 to be displaced downwardly on the valve nipple to the position shown in FIG. 3 where the valve is closed as the latch seal nipple continues upward.

With the latch seal nipple, the valve and the packer positions as shown in FIG. 3, the valve is closed and further upward motion of the latch seal nipple will disengage upper collet fingers 156 from top connection recess 146 so as the latch seal nipple is further withdrawn from the packer, the valve will be closed. A radially outwardly extending and upwardly facing shoulder 168 on the upper end of lower seal nipple segment 118 at the joint below valve collar assembly 120 abuts the lower end of lower collet fingers 138. Also, The enlarged portion of lower collet fingers 148 slips radially inward into lower valve nipple recess 140 thereby securing valve sleeve 136 to the valve nipple in the closed position. As the latch seal nipple continues upward, the valve member will remain in the position shown in FIG. 3. Because of the substantial upward pull on the well tubing and the attached latch seal nipple and because the valve member and its associated upper and lower latch collets are carried with the latch seal nipple, this transmits sufficient force to the upper collet members 156 to slide enlarged portion 158 out of top connection recess 146 into the bore of the top connection. FIG. 4 shows the latch seal nipple and valve assembly in a position above top connection recess 146. During upward motion of the valve assembly through top connection 16, the outer peripheral surfaces of upper collet enlarged portion 158 slides along the interior of the top connection bore and upper collet members 156 remain displaced into recess 142. When the upper collet members pass out of the bore of top connection 16, they are displaced outward to the free position while the lower collet member 148 remain with their enlarged portions 150 engaged in lower recess 140 to retain valve sleeve 136 in the closed position.

In normal practice, the latch seal nipple is pulled upward so the valve sleeve 136 and lower collet fingers 148 are substantially above the upper end of the packer and so the latch seal nipple can accommodate substantial longitudinal motion compensation between the tubing and the packer. Because port 126 through the latch seal nipple is blocked, fluid communication is established through the well tubing, the latch seal nipple and further through the packer without communicating to the annular cavity around the well tubing above the packer. In the event that the well tubing and the latch seal nipple are lowered in the well sufficient to move valve sleeve 136 into the packer, it will not reopen the valve. The inclination of collet latching surfaces 152 and 162 prevent the valve sleeve from being secured to the packer mandrel and thus opened as the latch seal nipple moves downward. As the valve sleeve moves downward, upper collet enlarged portion 158 moves outward into top connection recess 146 while lower collet enlarged portion 150 is retained in lower recess 140. Because the relative inclination of surface 162 is shallower than the inclination of surface 152, this permits upper collet enlarged portion 158 to slip from recess 146 without creating sufficient force to displace lower collet enlarged portion 150 from lower recess thereby retaining valve sleeve 136 in the closed position.

When it is desired to unset or release the packer, the tubing is raised and appropriately positioned and manipulated to release the slips by using the retrieval tool whereupon the latch seal nipple remains above the packer and does not have to reenter the bore of the packer mandrel. In order to reset the packer, it is necessary to remove the packer from the well for repair and refurbishing. After the packer is removed from a well, the valve assembly is manually repositioned in the open position and the seal nipple assembly is reinserted in the packer.

Although the valve assembly described above does not reopen upon reinsertion of the latch seal nipple into the packer, it is to be noted that inclined surfaces 152 and 162 along with top connection recess 146 and lower recess 140 can be modified to cause the valve to be reopened upon reinsertion of the latch seal nipple. This modification to the latching surfaces 152 and 162 consists of substantially exchanging their angular orientations and correspondingly shaping the mating surfaces of recesses 140 and 146. This configuration of latching surfaces for the collet fingers is shown in FIG. 6 and with the modified upper and lower latching surfaces indicated at 152A and 162A respectively.

Provided this modification is done, then merely pushing the latch seal nipple straight into the packer mandrel until it assumes the position shown in FIG. 1, will automatically displace the valve sleeve to the open position and latch locking sleeve 130 with the top connection 16. As the latch seal nipple is displaced into the packer, the valve member or sleeve is carried in the position shown in FIG. 4 and prevented from sliding upward due to the engagement of lower collet enlarged portion 150 with lower recess 140. This attachment of the valve member and the valve nipple is temporary and continues until upper collet members 156 pass top connection recess 146 and the enlarged portions thereof 158 are displaced outward into this recess. At this point, continued downward motion of the latch seal nipple will cause lower collet members 148 to have their enlarged portions withdrawn from lower recess 140 because of the gripping engagement between upper collet member lower latching surface 162A and the appropriate surface in recess 146. At this point, it is to be noted that the relative angular relation of upper collet lower latching surface 162A and lower collet upper latching surface 152A are selected so that a sufficient force is required to release the upper collet members from their associated recess and this force is greater than the retaining force of the lower collet members when the latch seal nipple is moving downward. After upper collet members 158 are engaged, the continued downward motion of the latch seal nipple will disengage lower collet members 148, because of the shallower inclination of latching surfaces 152A, and cause them to move radially outward and slide on nipple cylindrical exterior surface 138 and at the same time displace valve member 136 from the position covering port 126 thereby opening the valve. When the valve is opened and the latch seal nipple has been displaced sufficiently downward to bring upper collet members 158 into an abutting relation with valve nipple shoulder 144, then continued downward displacement of the latch seal nipple will urge these collet members from recess 146 by inclined surface 162A sliding on the lower surface of top connection recess 146. When this occurs, the continued downward motion of the latch seal nipple will eventually bring it into the position shown in FIG. 1. Shortly before the latch seal nipple reaches the position shown in FIG. 1, locking sleeve 130 engages the upper end of top connection 16. Due to the segmented construction of locking sleeve 130 and the latching threads on adjoining portions of these members, it is not necessary to rotate the members to accomplish the threaded connection. Merely pushing the latch seal nipple into the top connection will let the inclined surfaces of the threads slide past each other until a secure connection is achieved. It is to be noted that if desired, this connection can be made up by rotating the members.

As can be seen from the above, a valve assembly has been provided for use with a hydraulically set packer which will enable fluid communication to be established and maintained through the packer without leakage into the annular fluid cavity around the well tubing above the packer. This valve mechanism is open for setting the packer through fluid pressure applied in the tubing and it is closed upon raising a seal nipple assembly from the packers. Raising the seal nipple closes the valve and at the same time provides for motion compensation between the well tubing and the packer.