US2695066A - Hydraulically actuated well tool - Google Patents

Description

T. M. RAGAN HYDRAULICALLY ACTUATED WELL TOOL Nov. 23, 1954 3 Sheets-Sheet 1 Filed Oct. 18. 1949 Nov. 23, 1954 1-. M. RAGAN HYDRAULICALLY ACTUATED' WELL. TOOL 3 Sheets-Sheet 2 rllil'll'fllflll 'l vflllll'll'illlll INVENTOR.

M45111. PAGA/v, BY

m W W Filed Oct. 18. 1949 Nov. 23, 1954- T. M. RAGAN HYDRAULICALLY ACTUATED WELL TOOL 3 Sheets-Sheet 3 Filed Oct. 18, 1949 INVENTOR. 71/0/1445 1%. IPA 6AM,

t face Patented Nov. 23, 1954 2,695,066 HYDRAULKCALLY AETUATED WELL TOOL Thomas M. Rag

Downey, Califl, assignor to Baker Oil Tools, Ind,

The present invention relates to well. tools, and more particularly to well packers and the like adapted to be anchored in a well bore as a result of subjecting the tool to fluid pressure.

Well tools, such as well packers, may embody a back pressure valve for preventing return flow of fluids through the tool. However, during lowering of the tool in the well bore, it is desired to allow upward flow of fluid through it by initially preventing the back pressure valve from seating. The well tool is actuated by fluid pressure which is built up as a result of closing or restricting the tool passage, in order to prevent or limit downward flow of fluids therethrough. Such control of the passage has heretofore been obtained by dropping a valve element down the tubular string, to which the tool is secured, into engagement with a cooperable seat on the tool.

An object of the present invention is to provide a well too], such as a well packer, embodying an improved trip device for preventing or restricting downward flow of fluid through the tool, for the purpose of enabling the tool to be set hydraulically in the well bore.

Another object of the invention is to insure the ejecting of the trip device from the well tool after setting of the latter in the well bore.

Another object of the invention is to provide a hydraulically actuated Well tool, which can be subjected to fluid pressure without the necessity for lowering a valve element through the tubular string to which the tool is attached.

A further object of the invention is to provide an improved arrangement for initially preventing a back pressure valve from engaging its cooperable seat in a well tool during lowering of the tool in the well bore.

Yet a further object of the invention is to prevent the back pressure valve element from seating during lowering of the tool in the well bore and to permit such seating as an incident of setting the tool in the well bore.

A still further object of the invention is to utilize a single valve element, which is capable of function as a trip device in hydraulically setting a well tool in a well bore, and also as a back pressure valve in preventing return flow of fluid through the Well tool.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of several forms in which it may be embodied. Such forms are shown 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 such 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:

Figure 1 is a longitudinal section through a well packer disposed in a well casing, and containing one form of back pressure and trip device, the parts being disposed in position for lowering the tool in the well casing;

Fig. 2 is a view similar to Fig. 1, disclosing the well tool partly operated in the well bore;

Fig. 3 is an enlarged fragmentary section of the well tool, disclosing the parts in still another operative position;

Figs. 4 and 5 are cross-sections taken along the lines 4-4 and 5-5, respectively, on Fig. 1;

Fig. 6 is a view similar to Fig. l, disclosing the well tool fully set in the well casing;

Fig. 7 is a longitudinal section through the trip device portion of the well tool, illustrating the device in another operative position;

Fig. 8 is a view similar to Fig. 7, disclosing the trip device being ejected from the well tool;

Fig. 9 is a longitudinal section, similar to Fig. 1, of another specific form of well tool embodying the invention;

Fig. 10 is a longitudinal section similar to closing the tool partly set in the well casing;

Fig. 11 is a view similar to Fig. 9, disclosing the well tool fully anchored in packed-01f condition within the well casing;

Fig. 12 is a longitudinal section through a lower portion of the well tools disclosed in Fig. l and Fig. 9, illustrating another embodiment of back pressure valve and trip device.

As disclosed in the drawings, it is desired to set a Well packer A, or like tool, in a well casing B. The packer may be lowered to the desired setting point in the casing by the aid of a tubular string C, of drill pipe or tubing, and by actuating certain parts of the device hydraulically.

The well packer includes a main body comprising a tubular portion 10, an upper annular abutment ll threadedly secured at the upper end of the latter, and a lower guide and abutment l2 threadedly secured on its lower end. This lower guide and abutment may also constitute a valve housing for enclosing certain valve elements, to be described hereinafter.

A plurality of upper segmental slips 13 are disposed around the body adjacent its upper abutment llll. These slips have inner tapered surfaces 14 inclined in a downward and outward direction, being slidable along a companion tapered surface 15 on an upper frusto-conical expander 16 disposed around the body Ill. A plurality of shear screws 17, or similar frangible devices, initially secure the upper slips 13 to the upper expander 16, holding the slips in retracted position against the body 10. The upper slips have upwardly facing wickers or teeth 18 on their external portions for engagement with the inner wall of the well casing B, to prevent upward movement of the packer therewithin.

In a similar manner, a plurality of lower segmental slips 19 are disposed around the lower portion of the body adjacent the lower body guide and abutment 12. These lower slips have inner tapered surfaces 2! that are inclined in a downward and inward direction for cooperation with companion tapered surfaces 21 on a lower frusto-couical expander 22 mounted on the body of the tool. The lower slips are held in retracted position against the body by a plurality of shear screws 23, or other frangible devices, which initially secure them to the lower expander 22. The lower slips have downwardly facing wickers or teeth 24 for engagement with the wall of the casing B, for preventing downward movement of the well packer therewithin.

An annular seal is to be provided between the packer body 10 and the wall of the well casing. This seal may be furnished by a packing sleeve 25, which may be of synthetic rubber, mounted on the body between the upper and lower expanders i6, 22. Initially, the packing sleeve 25 is in retracted position and has a substantial clearance with the well casing, the ends of the sleeve abutting or being adjacent the upper and lower expanders 16, 22. The sleeve 25 is urged outwardly against the casing by moving the upper and lower expanders toward each other, for the purpose of foreshortening the sleeve and compressing it firmly between the body It) and easing B, in a manner described hereinafter.

The well packer A is lowered in the well casing 13 by the aid of the tubular string C. The lower end of this tubular string is threadedly secured to a tubular adapter 26 that is threaded onto the upper end of a tubular mandrel 27 extending into the packer body It). Leakage between the body and mandrel may be prevented by providing one or more seal rings 28, such as rubber 0 rings, in peripheral grooves 29 in the mandrel engaging the body wall.

The tubular mandrel extends through a coupling sleeve 30 having left-hand threads 31 on its periphery engaging Fig. 9, discompanion threads on the upper end of the packer body 10. The coupling sleeve extends outwardly from the upper end of the body and may have a pair of elongate longitudinal slots 32 slidably receiving pins 33 secured to the upper portion of the mandrel 27. Initially, the mandrel is maintained in a lower position with respect to the coupling sleeve 30, with its pins 33 in the lower portions of the longitudinal slots 32, by one or more shear screws 34 threaded into the upper portion of the coupling sleeve and mandrel, as shown in Fig. 1. When the parts are in this position, a shoulder 35 at the upper end of the lower head portion 36 of the mandrel 27 is disposed a substantial distance below the lower end of the coupling sleeve 30. As described hereinafter, this lower shoulder may be moved relatively upwardly into engagement with the lower end of the coupling sleeve to effect anchoring of the well packer in packed-off condition within the well casing. The pin and slot connection 33, 32 enables the tubular string C and mandrel 27 to be rotated, for the purpose of unthreading the coupling sleeve 30 from the packer body 10, which allows the entire tubular mandrel to be withdrawn from the latter.

Originally, the upper and lower expanders 16, 22 are spaced apart a sufficient distance to allow the packing sleeve 25 to occupy its retracted position. The lower expander 22 is held in its original position by one or more shear screws 37 threaded through the expander and into the packer body 10. The upper expander 16 is held in its original position by a plurality of shear screws 38, of relatively long extent, threaded into the expander 16 and projecting through elongate body slots 39, for threaded reception in the tubular mandrel 27 below its shoulder 35. These screws 38 may extend through short guide blocks 40 slidable in the body slots. The guide blocks 40 have the purpose of insuring proper shearing of the elongate screws 38, as explained hereinafter.

The well packer A is run in the well bore on the lower end of the tubular string C and with its parts occupying the retracted positions disclosed in Fig. 1. In anchoring the tool in packed-off condition in the well casing, it is desired first to expand the upper slips 13 against the casing B, and then to move the packer body upwardly, for the purpose of foreshortening the packing element 25 and compressing it between the body 10 and easing B, and also to shift the lower slips 19 outwardly against the well casing. This sequence of events is obtained by properly proportioning the relative strengths of the various sets of shear screws in the tool. Thus, the screws 17 holding the upper slips 13 to the upper expander 16 have a lesser combined shear value than the elongate screws 38 initially securing the upper expander 16 to the tubular mandrel 27. These latter screws, in turn, have a lesser combined shear strength than the shear strength of the screws 37, 23 holding the lower expander 22 to the packer body 10 and the lower slips 19 to the lower expander.

When the location in the well casing has been reached at which the well packer is to be set, the passage through the lower guide and abutment portion 12 of the body is closed, to enable the pressure of the fluid in the tubular string C, tubular mandrel 27, and lower portion of the packer body 10 to be increased. This fluid under pressure acts across the area of the body below the mandrel head 36 in several directions. The resultant area over which the fluid under presure acts on the body is the cross-sectional area R across the body bore 41. The fluid acts on this resultant area R in a downward direction. With the valve housing 12 closed against downward flow of fluid, the building up of pressure in the body of the packer urges the body 10 downwardly along the tubular mandrel 27 which is attached to the tubular string C. All parts of the well packer are urged downwardly with the exception of the upper expander 16, since the latter is secured to the mandrel 27 by the elongate shear screws 38. This downward force imposed on the packer body 10 is exerted in a downward direction upon the upper slips 13 through the agency of the upper abutment 11. When the pressure increases sufficiently, the screws 34 and upper shear screws 17 are disrupted and the packer body 10 moves downwardly to slide the upper slips 13 in a downward direction along the stationary upper expander 16. In view of the inclined surfaces 14, 16 on the slips and upper expander, the slips 13 are urged outwardly against the casing, as disclosed in Fig. 2.

Such downward movement of the body 10 relative to the upper expander 16 is permitted, since the elongate shear screws 38 extend through the slots 39 in the packet body 10. In addition, the coupling sleeve 30, threadedly secured to the body 10, can also move downwardly without restraint, in view of the fact that the elongate slots 32 in the sleeve are of suflicient length to avoid interference with the coupling pins 33 extending outwardly from the tubular mandrel 27.

When the upper slips 13 have been engaged with the casing B, there is still a substantial distance or space between the mandrel shoulder 35 and the lower end of the coupling sleeve 30. An upward strain can then be taken on the tubular string C and mandrel 27 of suflicient extent to shear the elongate screws 38, freeing the mandrel from the upper expander 16. The mandrel 27 can then move upwardly until its shoulder 35 engages the lower end of the coupling sleeve 30. Such engagement precludes further relative upward movement of the mandrel 27 within the packer body 10 and the coupling sleeve 30. A continuation of the upward strain and movement then moves the packer body 10, and all of the packer parts below the upper expander 16, in an upward direction until the upper end of the packer sleeve 25 engages the upper expander 16. Since the latter is prevented from moving upwardly by virtue of its wedging engagement within the slips 13, continued upward movement of the mandrel 2'7 and packer body 10 will move the lower expander 22 toward the upper expander 16, foreshortening the packing sleeve and compressing it between the expanders, which is associated with outward expansion of the packing against the wall of the well casing B, and its provision of a firm seal between the periphery of the body 10 and the casing.

As the upward strain on the mandrel 27 and packer body 10 is increased, the compressed packing 25 restrains upward movement of the lower expander 22 with the body. Accordingly, the imposition of suflicient upward force on the body shears the screws 37 holding the lower expander 22 to the body 10, and also the screws 23 holding the lower slips 19 to the lower expander. The body then moves upwardly within the lower expander 22, with its lower abutment 12 sliding the lower slips 19 upwardly along the lower expander and radially outwardly into anchoring engagement with the wall of the well casing B.

A sufficient upward strain is taken on the tubular string C, mandrel 27, to insure that the slips 13, 19 are firmly embedded in the casing B, with the packing 25 providing an annular leakpro)of seal between the body 10 and the casing B (Fig. 6

Upward movement of the well packer A within the casing is prevented by the embedding of the upper slips 13 in the casing wall. Downward movement of the packer body is prevented by the wickers 24 on the lower slips 19 embedding themselves in the casing wall. The downward force on the packer body 10 is transmitted to the lower slips 19 through a suitable lock device. As disclosed in the drawings, this lock device may take the form of a split, contractile sleeve 45 disposed within a recess 46 in the lower expander 22, and having inner upwardly facing teeth 47 cooperable with companion downwardly facing ratchet teeth 48 on the exterior of the packer body 10. The outer portion of the ring 45 is provided with a plurality of downward and inwardly inclined cam faces 49 engageable with companion cam faces 50 in the lower expander 22. Any downward force imposed on the body 10 is transmitted through the teeth 48, 47 to the ring 45, the tapered surfaces 49, 50 on the ring and expander urging the ring more firmly against the body 10, and also transmitting the downward force to the lower expander 22, from where the force passes through the lower slips 19 to the well casing B. The ratchet teeth 48, however, do not interfere with upward movement of the body 10 within the lower expander 22, inasmuch as the split ring 45 is caused to expand automatically, avoiding interference with such upward move ment.

After the well packer A has been firmly anchored in the well casing and a particular function or operation performed, the tubing string C, mandrel 27 and coupling sleeve 30 may be removed by rotating the tubing string to the right, which, through the agency of the pin and slot connection 33, 32, between the tubing mandrel 27 and coupling sleeve 30 unthreads the latter from the packer body 10, and allows the mandrel 27 and coupling sleeve 30 to be elevated to the top of the well bore.

coupling sleeve 30 and body 10, I

As disclosed in Figs. 1 to 8, inclusive, a valve arrangement is employed which is capable of preventing return flow of fluids through the well packer A, after it has been set in the well casing, and which also precludes downward flow of fluid through the well packer until after the latter has been hydraulically actuated. The valve arrangement also enables fluid to flow upwardly through the well packer when it is being run down through the well casing, to allow the tubing string C to fill automatically with the well fluid.

The valve device includes the lower guide and abutment 12, which forms a valve housing. The lower end of the body may have a flexible valve seat 60, of rubber or the like, engageable by a back pressure and trip ball '61 disposed in the valve housing. The ball may move upwardly into engagement with the seat to prevent upward or reverse flow of fluid through the packer body 143. However, originally, the ball 61 is prevented from engaging its seat 66 by a depending extension 27a of the tubular mandrel threaded into the mandrel head 36. When the mandrel 27 is connected to the coupling sleeve 30 and body It) through the agency of its shear pin 34, a plurality of fingers 62 on the extension 27a project through the valve seat 66, and will engage the ball 61 to forestall its upward engagement with the valve seat.

The back pressure ball 61 is adapted to engage the upper end or seat 63 of an inner valve sleeve 64, that is slidable within an outer valve sleeve 65, the latter making a close slidingfit with the lower portion 12a of the valve housing '12. The inner sleeve valve 64 initially occupies an upper position relative to the outer sleeve valve 65, being held in this relationship by one or more shear screws or pins 66 connecting the sleeve valves together. When the pins are intact, the lower end 67 of the inner sleeve valve 6 -3 isdisposed above a plurality of side ports 63 extending through the Wall of the outer sleeve valve 65 below the lower end of the valve housing 112. Originally, the outer sleeve valve 65 is connected to the valve housing 12 by one or more shear pins or screws 69, and leakage along the exterior of the valve 65 is prevented by a side seal 70 engaging the wall of the housing portion 12a.

While the tool is being lowered through the well casing, fluid can enter the tool through the lower ports 63, flowing upwardly through the sleeves 65, 6 unseating the ball 61 from the upper sleeve 64 and flowing up through the tubular mandrel 27 and into the tubular string C. When the well packer A is to be anchored in the well casing, the pumps at the top of the well bore are started, urging the fluid in the tubing string C, tubular mandrel 27 and packer body It) downwardly. This seats the back pressure and trip ball 61 against the upper end 63 of the upper sleeve valve 64, closing the passage through the latter and allowing the pressure to be built up within the tool for the purpose of tripping the upper set of slips 13, in the manner described above. Such tripping action occurs as a result of downward movement of the packer body it) along the tubular mandrel 27. During this downward movement, the valve seat 60 moves downwardly below the tubular mandrel extension 27a, and, therefore, removes the fingers 62 on the extension from interference with the ability of the back pressure ball 61 to move upwardly into engagement with the valve seat 6%) (see Fig. 2).

After the upper slips 13 have been set, the sleeve valves 64, 65 can be ejected hydraulically from the valve housing 12, so as not to interfere with the downward pumping of cement slurry, or other fluids, through the Well packer A. Such ejection can take place immediately after the tripping of the upper slips 13, or after the full setting of the packer in the well casing, as desired. An increase in the pressure of the fluid in the tubular mandrel 27 and valve housing 12 exerts a downward force on the trip ball 61, which is engaging the inner sleeve valve 66, this downward force being transmitted through the inner sleeve valve 64 to the shear pins 66. These shear pins have a much greater shear value than the upper slip shear screws 17, but a lesser shear value than the lower pins 69 holding the outer sleeve valve to the housing 12. When sufficient hydraulic force has been exerted to overcome the shearlstrength of the pins 66, they are disrupted and the inner sleeve valve 64 moved downwardly within theouter sleeve valve 65 to a position in which the inner sleeve valve 64. closes the ports 68 through the outer sleeve valve (Fig. 7).

.The trip ball 61 may .now engage a valve seat 75 at sleeve valve 65, and pressure may now be imposed upon the trip ball 61, which pressure is transmitted through the outer sleeve valve 65 to the other shear pins 69. Eventually, these shear pins 69 are disrupted when the fluid pressure exceeds a predetermined value, and the sleeve valves 64, 65 are moved downwardlyout of the valve housing. Before this occurs, however, the trip ball 61 engages inwardly directed ribs 76 in the valve housing 12, and is precluded from moving downwardly to a further extent. But since the tuner sleeve valve 64 has closed the ports 68 through the outer sleeve valve 65, the two valves together const1tute a piston that is acted upon by the fluid under pres- Sure within the valve housing 12, such fluid forcing the piston in a downward direction completely out of the valve housing, in the manner illustrated in Fig. 8.

After the sleeves 64, 65 have been ejected from the valve housing 12, fluids can be pumped freely through the tubular string C and into the valve housing 12, passlng around the ball 61 and between the circumferentially spaced, inwardly directed ribs 76, and out through the lower end of the housing and guide. In the event that fluids tend to flow in a reverse direction, they carry the ball 61 upwardly into engagement with the valve seat 69, precluding such reverse flow. To insure upward seatmg of the ball against the seat, it preferably has a specific gravity which is less than that of the cement slurry, so as to be buoyant in the latter.

The valve arrangement just described is disclosed in Figs. 9, l0 and ll in connection with a different specific form of well packer D. The tubular mandrel 2'7, coupling sleeve 36 and body litia are disposed in essentially the same relationship as in the other Well packer. In addition, the packer body 16a carries a set of upper segmental slips 13a adapted to be moved into engagement with the casing by an upper expander cone 16a initially retained in retracted position by one or more shear screws 38:: attaching it to the main body. The upper slips 13a are similarly retained initially in retracted position by shear screws 17a securing them to the expander cone. A lower set of segmental slips 1% is held initially in retracted position by being attached to the lower expander cone 22a through shear screws 23a, this latter cone being initially held in attached relation to the body Zita by suitable frangible connections in the form of shear screws 37a. The upper sets of screws 33a, 17a have a lower shear value than the lower sets 23a, 37a, to permit prior setting of the upper slips 130.

A packing sleeve 25a of synthetic or natural rubber is positioned between and suitably secured to the ends of the expander cones 16a, 22a, being retained initially free from contact with the casing wall, but being capable of foreshortening and expansion into engagement therewith, and with the main body itla of the packer D.

The same valve assembly housing and valve mechanism as disclosed in Figs. 1 to 8, inclusive, is secured to the lower end of the main packer body Ella, and cooperates with the tubular mandrel extension 270 in essentially the same manner.

The packer D is run into the casing B to the desired point at which it is to be anchored in paclted-off condition (as in Fig. l). The fluid in the tubular string C and packer D is placed under pressure, as permitted by engagement of the trip and back pressure ball 61 with the upper seat 63 on the inner sleeve 64. Such fluid under pressure flows around the lower portion of the tubular mandrel 27, and up through the annulus 8-5 between the mandrel 27 and packer body 10a, the fluid flowin'. outwardly through ports or holes 81 opening through the body into the interior of the packing sleeve 250. This fluid under pressure inflates and elongates the packing sleeve 25a (in the manner illustrated in Fig. 10), exerting a force upon the upper cone 36a of sufficient extent to disrupt the shear screws 38a, 17a, sliding the upper cone 16a upwardly within the upper slips 13a, and expanding the latter radially outward along the upper abutment 11a into gripping engagement with the casing B.

After setting the upper slips 13a, an upward strain may be taken on the tubing string C of sufi" ient extent to shear the screws 34 holding the tubular mandrel 27 to the coupling sleeve 36. A continuation of this strain shifts the mandrel 27 upwardly within the body lila and removes the lower end of the mandrel extension 27a from interfering with the ability of the back pressure the upper end of the outer ball 61 to move upwardly into engagement with the valve seat 60 provided in the lower end of the body. The tubular mandrel 27 is moved upwardly until its shoulder 35 engages the lower end of the coupling sleeve 30, whereupon the body 10a is moved upwardly to move the lower expander 22a toward the upper expander 16a, foreshortening the packing sleeve 25a and compressing it into firm sealing engagement between the body 10a and the well casing B. A continuation of this upward strain and movement of the body shears the lower screws 37a, 23a and causes the lower abutment 12 to slide the lower slips 19a upwardly along the lower expander 22a and radially outward into anchoring engagement with the casing. The packer is now in fully set position, as disclosed in Fig. 11.

The fluid pressure may be increased for the purpose of ejecting the inner and outer slip sleeves 64, 65 of the tripping device from the valve housing 12, in the same manner as described in connection with the other well packer A, the back pressure ball 61 being limited in its downward movement by engaging the inwardly extending ribs 76 within the valve housing.

Fluid, such as cement slurry, may now be pumped downwardly through the tubular string C and well packer D for outward passage through the lower end of the valve housing 12. Return flow of such fluids is prevented by upward engagement of the back pressure ball 61 with the body seat 60.

After the desired operation has been performed in the well casing, the tubular string C may be rotated to rotate the coupling sleeve 30 and unscrew it from the body 1011, allowing the tubular string C, mandrel 27 and coupling sleeve 30 to be removed to the top of the well bore.

The upper slips 13a cooperate with the upper cone 16a to prevent upward movement of the well packer D within the well casing B. Downward movement of the packer body 10a may be prevented by a suitable locking device which may include downwardly facing ratchet teeth 90 on the periphery of the body cooperable with a split ratchet ring 91 contained within a groove 92 in the upper expander 16a.

In Fig. 12, a modified form of valve device is disclosed, which may be employed in connection with both forms of well packers A, D disclosed.

The valve arrangement disclosed in Fig. 9 employs a single sleeve 93 secured to the valve housing 12 by one or more shear pins 94. The trip ball 61 will engage the upper seat 95 on the sleeve to prevent downward passage of fluid through the Well packer, and allows the fluid pressure to be increased for the purpose of setting the packer against the wall of the well casing. Thereafter, the imposition of sufficient pressure will shear the screws 94 and force the sleeve 93 downwardly out of the housing 12. To guard against leakage of fluid around the valve sleeve, a side seal 96 may be provided in a groove 97 at the lower portion 98 of the sleeve, in sealing engagement with the cylindrical wall of the lower housing portion 12a. When the shear screws 94 are disrupted, the sleeve valve element 93 is moved downwardly until the ball 61 engages the ribs 76. When this occurs, the lower portion 98 of the sleeve has already been forced out of the housing 12, and its upper reduced diameter portion 99, which does not slidably seal with the housing 12, will then allow the sleeve 93 to drop or gravitate completely out of the housing 12.

It is, accordingly, apparent that a well tool has been disclosed which is actuated hydraulically and which precludes the necessity for a tripping valve element to be gravitated down the tubular string into engagement with the trip seat. The tripping valve element 61 is also caused to function as a back pressure device, this device being prevented from engaging its cooperable seat during lowering of the well tools in the well casing. The incident of setting the well packer removes the barrier against upward seating of the back pressure valve element.

It is also to be noted that the trip device is ejected from the well tool, to allow a free opening through its lower end, through which cement slurry, and other well fluids, can be pumped readily.

The inventor claims:

1. In well apparatus: body means having a fluid passage and a first valve seat around said passage; means providing a second valve seat in said body means below said first valve seat; a valve element movable upwardly into seating engagement with said first valve seat and downwardly into seating engagement with said second valve seat; initially retracted means on said body means expandible laterally outward in response to fluid pressure built up in said body means after seating engagement of said valve element with said second valve seat; releasable means securing said second valve seat to said body means and releasable by fluid pressure built up in said body means when said valve element is in seating engagement with said second valve seat; and means retaining said valve element in said body means after release of said releasable means.

2. In well apparatus: body means having a fluid passage and a first valve seat around said passage; means providing a second valve seat in said body means below said first valve seat; a valve element movable upwardly into seating engagement with said first valve seat and downwardly into seating engagement with said second valve seat; initially retracted means on said body means expandible laterally outward in response to fluid pressure built up in said body means after seating engagement of said valve element with said second valve seat; frangible means securing said second valve seat to said body means to enable said second valve seat to be ejected hydraulically from said body means; and means retaining said valve element in said body means upon ejection of said second valve seat from said body means.

3. In well apparatus: body means having a fluid passage and a first valve seat around said passage; means providing a second valve seat in said body means below said first valve seat; a valve element movable upwardly into seating engagement with said first valve seat and downwardly into seating engagement with said second valve seat; initially retracted means on said body means expandible laterally outward in response to fluid pressure built up in said body means after seating engagement of said valve element with said second valve seat; releasable means securing said second valve seat to said body means to enable said second valve seat to be ejected hydraulically from said body means upon release of said releasable means; and means engageable with said valve element to limit its downward movement within said body means after engagement of said valve element with said second valve seat and release of said releasable means.

4. In well apparatus: body means having a fluid passage and a first valve seat around said passage; a ported sleeve in said body means below said seat; releasable means securing said sleeve to said body means; a second sleeve within said ported sleeve; releasable means securing said second sleeve to said ported sleeve in open position with respect to the port of said ported sleeve; said second sleeve having a second valve seat; and a valve element movable upwardly into engagement with said first valve seat and downwardly into engagement with said second valve seat.

5. In well apparatus: body means having a fluid passage and a first valve seat around said passage; a ported sleeve in said body means below said seat, said sleeve having a closed lower end; frangible means securing said sleeve to said body means; a second sleeve within said ported sleeve; frangible means securing said second sleeve to said ported sleeve in open portion with respect to the port of said ported sleeve; said second sleeve having a second valve seat; and a valve element movable upwardly into engagement with said first valve seat and downwardly into engagement with said second valve seat.

6. In well apparatus: body means having a fluid passage; a ported sleeve in said passage; frangible means securing said sleeve to said body means; a second sleeve within said ported sleeve; frangible means securing said second sleeve to said ported sleeve in open position with respect to the port through said ported sleeve; said second sleeve having a valve seat; and a valve element movable downwardly into engagement with said valve seat to close said fluid passage.

7. In well apparatus: body means having a fluid passage and a first valve seat around said passage; a ported sleeve in said body means below said seat, said sleeve having a closed lower end; frangible means securing said sleeve to said body means; a second sleeve within said ported sleeve; frangible means securing said second sleeve to said ported sleeve in open position with respect to the port of said ported sleeve; said second sleeve having a second valve seat; a valve element movable upwardly into seating engagement with said first valve seat and downwardly into seating engagement with said second valve seat; and initially retracted means on said body means expandible laterally outward in response to fluid pressure built up in said body means after seating engagement of said valve element with said second valve seat.

8. In well apparatus: body means having a fluid passage and a first valve seat around said passage; a ported sleeve in said body means below said seat, said sleeve having a closed lower end; frangible means securing said sleeve to said body means; a second sleeve within said ported sleeve; frangible means securing said second sleeve to said ported sleeve in open position with respect to the port of said ported sleeve; said second sleeve aving a second valve seat; a valve element movable upwardly into seating engagement with said first valve seat and downwardly into seating engagement with said second valve seat; initially retracted means on said body means expandible laterally outward in response to fluid pressure built up in said body means of said valve element with said second valve seat; and means engageable with said valve element to limit its downward movement within said body means after seating engagement of said valve element with said second valve seat and release of both of said frangible means.

9. In well apparatus: passage and a valve seat element movable upwardly body means having a fluid around said passage; a valve into seating engagement with said seat; a member within said body means engageable with said valve element to prevent its seating engagement with said seat; initially retracted means mounted on said body means and engageable by said body means upon longitudinal movement thereof; and means receiving fluid under pressure from said passage for hydraulically shifting said body means longitudinally with respect to said member to expand said initially retracted means laterally outward and move said seat longitudinally away from the lower end of said member to allow said valve element to engage said seat.

10. In well apparatus: body means ehaving a fluid passage and a valve seat around said passage; a valve element in said body means movable upwardly into seating engagement with said seat to prevent flow through said passage; a member within said body means engageable with said valve element to prevent seating engagement with said seat, said member being connectible to a running-in string; a sleeve detachably coupled to said body means; a connection between said sleeve and said member to provide relative sliding movement therebetween as well as joint movement thereof to enable said member to operate said sleeve to uncouple said sleeve from said body means; initially retracted means mounted on said body means and engageable by said body means upon longitudinal movement thereof; means a receiving fluid under pressure from said passage for hydraulically shifting said body means and sleeve longitudinally with respect to said member to expand said initially retracted means laterally outward and move said seat below the lower end of said member to allow said valve element to engage said seat.

11. In well apparatus: body means having a fluid passage and a valve seat around said passage; a valve element in said body means movable upwardly into seating engagement with said seat to prevent flow through said passage; a member within said body means engageable with said valve element to prevent seating engagement with said seat, said member being connectible to a running-in string; a sleeve detachably coupled to said after seating engagement body means; a connection between said sleeve and said member to provide relative sliding movement therebetween as Well as joint movement thereof to enable said member to operate said sleeve to uncouple said sleeve from said body means; initially retracted means mounted on said body means and engageable by said body means upon downward movement thereof; means receiving fluid under pressure from said passage for hydraulically shifting said body means and sleeve downwardly along said member to expand said initially retracted means laterally outward and move said seat downwardly below the lower end of said member to allow said valve element to engage said seat.

12. In well apparatus: body means having a fluid passage and a first valve seat around said passage; means providing a second valve seat in said body means below said first valve seat; a valve element movable upwardly into seating engagement with said first valve seat and downwardly into seating engagement with said second valve seat; a member within said body means engageable with said valve element to prevent its seating engagement with said first valve seat; and initially retracted means on said body means expandible laterally outward in response to fluid pressure built up in said body means after seating engagement of said valve element with said second valve seat.

13. In well apparatus: body means having a fluid passage and a first valve seat around said passage; means providing a second valve seat in said body means below said first valve seat; a valve element movable upwardly into seating engagement with said first valve seat and downwardly into seating engagement with said second valve seat; a member within said body means 14. In well apparatus: body means having a fluid passage and a valve seat around said passage; a valve element movable upwardly into seating engagement with said seat; a member References Cited in the file of this patent UNITED STATES PATENTS I

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