Tool For Running On A Drill String In A Well Bore

Abstract

A tool for running on a drill string in a well bore carries inflatable packer means to close off the well bore adjacent the tool. The tool includes a body having a longitudinal bore therethrough with seating means and shock absorbing means for absorbing the shock of seating a bore close off means to close off the bore in the drill string. The tool body may include stabilizer means to aid in drilling straighter holes.

Description

In one form of the invention the tool is in the drill string near the drilling bit for receiving a sample collector which is inserted in the drill string at the earth's surface and dropped or pumped down the drill string to the seating means in the tool.

Pressure applied in the drill string at the earth's surface causes the inflatable packer means to inflate and seal off the well bore and the sample collector to open to collect a sample from the well bore beneath the inflated packer means. Thereafter as the pressure in the drill string is reduced at the earth's surface, the sample collector closes and the inflated packer deflates. The tool includes valve means responsive to the pressure differential between the drill string and the well bore above the inflatable packer means to sequentially perform the above steps and cause deflation of the inflatable packer means under substantially all well conditions.

DESCRIPTION OF THE PRIOR ART

The prior art that applicant is aware of includes in applicant's opinion, some of the closest references appear to be Hyde, U.S. Pat. No. 3,111,169; Cochrum et al., U.S. Pat. No. 3,503,445; Warrington, U.S. Pat. No. 3,332,215; Hughes, U.S. Pat. No. 2,862,562; Boynton, U.S. Pat. No. 2,301,190; Malone U.S. Pat. No. 3,529,665; and Williams et al., U.S. Pat. No. 2,338,369.

However, none of the prior art with which applicant is familiar provides a construction which functions in the same manner as applicant's. By way of example only, the prior art does not include valve means which sequentially functions responsive to the pressure differential between the drill string and the well bore above the inflatable packer means, and to cause deflation of the inflatable packer means under substantially all well bore conditions.

Various devices for closing off the well bore of a drill string and the well bore surrounding the drill string while the drill string remains within the well bore have been provided, as have sample collecting arrangements for use in connection with such constructions. One problem attendant with such prior art devices is that their construction and function are such that it is difficult to selectively sequentially control the operation of the tool in a desired manner. Another objection is that their construction and function is such that it is difficult to selectively and sequentially control the operation of the tool in a desired manner so as to assure a minimum amount of, if not complete, lack of contamination of the sample collected in the sample collector by fluids from other portions of the well bore or drill string other than that particular formation which is to be tested.

Additionally, the prior art constructions do not employ a shock absorber for receiving a tool such as a sample tool, or other bore close off device such as a go devil in a manner to inhibit damage thereto, or to enable the tool to be pumped or dropped down the drill string into seated position.

Another problem encountered with such prior art devices is that there is no positive means to assure that the inflatable element carried by the tool in the drill string is deflated after the tool has been operated while the drill string is in the well bore so that normal drilling operations may be continued without possible damage to the inflatable element carried on the rotating drill string.

Still another disadvantage with prior art devices with which applicant is familiar is that they are complicated and require a seemingly excessive number of moving parts and are somewhat difficult to service and maintain in uninterrupted use during normal drilling operations, while yet permitting a sample of a particular formation to be taken when desired.

Other devices do not provide an arrangement for equalization of the pressure above and below the inflatable element with the interior of the inflatable element, while the inflatable element is being deflated.

None of the prior art devices with which applicant is familiar employ an arrangement wherein the operation of the device is effected by control valve means which is responsive to the pressure in the drill string above the bore close off tool, or sample collector, with reference to the pressure in the well bore above the inflatable packer means.

Also excessive force must be employed with prior art devices to unseat the sample tool.

Another disadvantage with prior art devices is that since they are positioned in the drill string near the drilling bit and are of a smaller diameter than the drill collars in the drill string, deviation of the well bore may result under some formation conditions.

SUMMARY OF THE INVENTION

An object of the present invention is to provide an arrangement which may be utilized as a packoff tool for closing off the well bore annulus and the drill string bore while the drill string remains in the well bore with a minimum number of moving parts and performing such functions in a desired sequential manner.

Another object of the present invention is to provide an arrangement which may be utilized as a packoff tool for closing off the well bore annulus and the drill string bore while the drill string remains in the well bore with a minimum number of moving parts and performing such functions in a desired sequential manner. A sample collecting chamber with valve means to open and close the sample collecting chamber for communication with the well bore is adapted to be received in the tool for collecting a sample of fluid from a desired formation after the well bore annulus and drill string have been closed off.

Yet a further object of the present invention is to provide an arrangement which may be utilized as a packoff tool for closing off the well bore annulus and the drill string bore while the drill string remains in the well bore with a minimum number of moving parts and performing such functions in a desired sequential manner. A sample collecting chamber with valve means to open and close the sample collecting chamber for communication with the well bore is adapted to be received in the tool for collecting a sample of fluid from a desired formation after the well bore annulus and drill string have been closed off. A shock absorbing arrangement is arranged in the tool for receiving the impact of seating the sample tool therein and a control valve is provided in the tool to stepwise and sequentially operate the valve in the sampler to aid in assuring that it opens and closes at the proper intervals and thereby inhibit contamination of the sample collected in the sample collection chamber by fluids from the well bore.

The tool includes fluid passage means for equalizing the interior of the inflatable element with the bore as well as for equalizing well bore pressure above and below the inflatable element during deflation of the inflatable element.

Fluid passage means are provided in the tool, so that as pressure in the drill string is increased, communication from the well bore to the inflatable element is closed off and then fluid is conducted from the drill string to the inflatable element for inflation thereof.

Continued increase in drill string pressure manipulates the control valve means to open the sample collector valve to enable a fluid sample to be collected in the sample collector.

After the sample collector has been retained open a desired time interval for collection of a sample from the formation sealed off by the inflatable element, the pressure in the drill string bore is reduced to manipulate the control valve to close the sample collector valve. Continued reduction of drill string pressure manipulates the control valve to communicate the element with the well bore annulus for deflation thereof as well as communicating the well bore above and below the inflatable element to aid in deflation of the inflatable element after the sample has been collected and closed off in the sample collector.

Reduction of drill string pressure is continued, and when such pressure exceeds well bore pressure above the inflated element by a predetermined amount, the control valve causes the interior of the inflatable element to communicate with the well bore to assure deflation of the inflatable element.

Also, the arrangement which is associated with the control valve to communicate the interior of the inflated element with the well bore at a predetermined pressure differential between the drill string bore pressure and the pressure in the well bore annulus is such that the control valve will not initially move until such pressure differential is overcome during the initial stages of operation of the tool.

The invention including the control valve means functions in response to the pressure in the drill string above the sample collector, or bore close off means, with reference to the pressure in the well bore above the inflatable packer means.

Also, the inflatable element includes an end arrangement and a manner of supporting the inflatable element on the body to assist in deflation of the element and to aid in retaining it in deflated position during normal drilling operations.

Still another object of the present invention is to provide a tool for use with a drilling string in a well bore including a body for connection in the drill string including stabilizer means on the exterior surface of the body and reinforced inflatable means carried by said body intermediate the ends of the stabilizer arrangement.

All of the foregoing is accomplished with a relatively simple arrangement which is constructed and arranged with a minimum number of moving parts to control the operation of the tool in a predetermined, selected and sequential stepwise manner.

Another object is to provide a tool which overcomes the disadvantages of prior art devices as noted herein.

Other advantages of the present invention will become apparent from a consideration of the following descriptions and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevation illustrating the form of the present invention wherein it is employed in the drill string with the body providing a stabilizer arrangement adjacent the inflatable element to assist in proper drilling operations in some formations encountered;

FIG. 2 is a vertical sectional view diagrammatically illustrating the form of the invention shown in FIG. 1 and illustrates a body with a reinforced element thereon, a seating sleeve means within the bore of the body including a shock absorbing means, a control valve, the fluid passage means for communicating the well bore with the interior of the inflatable element and with the well bore thereabove and therebelow as well as other fluid passage means in the tool;

FIG. 3 is a sectional view similar to FIG. 1 but illustrates a sample collector seated within the seating sleeve means and with the seating sleeve means moved for communicating drill string pressure to the control valve for subsequent operation of the tool in a desired manner;

FIG. 3A is a partial sectional view illustrating the position of the control valve after it has moved to close communication between the well bore and inflatable element and open the drill string bore to the inflatable element while retaining communication above and below the inflatable element;

FIG. 3B illustrates the position of the control valve after it has closed off the equalizing passage between the well bore above and below the inflatable element and shows the position of the control valve for conducting pressure from the drill string bore through the tool to inflate the element;

FIG. 4 is a vertical sectional view of the tool showing the element inflated to close off the portion of the well bore therebelow from that portion of the well bore thereabove and with the control valve moved to communicate pressure from the well bore to one end of the valve in the sample collector while permitting the drill string bore pressure to act upon the other end thereof to move the sample collector valve to open the sample collector for receiving the sample of fluid from the formation sealed off by the inflatable element;

FIG. 4A is a partial sectional view showing the position of the control valve after the sample has been collected in the chamber for actuation of the sample valve to close the sample collector;

FIG. 4B illustrates the position of the control valve for reestablishing communication above and below the inflatable element in the well bore immediately prior to closing off the drill string bore to the inflatable element and opening the inflatable element through the tool and control valve to the well bore annulus for deflation thereof;

FIG. 5 is a sectional view of an alternate embodiment of the invention; and

FIG. 6 is a sectional view of another form of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention will be described in detail wherein a sample collector is dropped down the drill string; however, in some instances it may be desirable to drop a device for seating and closing off the bore in the drill string to thereafter enable the present invention to operate as a safety tool and close the well bore as well as the drill string bore.

Accordingly, the detail description of the present invention as employed in conjunction with a sample collector is merely for purposes of illustration and is not intended as a limitation in the use of the invention.

In FIG. 1, the invention is referred to generally by the numeral 10 and includes a body 11 which, if desired, may include a stabilizer configuration represented at 13 thereon with the reinforced inflatable element referred to generally at 14 therebetween. A drill bit is shown at 15 as being connected in the drill string, and it can be appreciated that while the invention is shown as being connected immediately above the drill bit in the drill string and will be described in such relation in connection with the present embodiment, for practical purposes, the present invention may be employed in any position in the drill string desired. The stabilizer arrangement 13 on the body 11 aids in drilling a straighter hole through some types of formations that may be encountered. For example, the stabilizer arrangement may be a noncircular exterior surface on the body 11, such as in the form of a square drill collar, or it may be a plurality of circumferentially spaced projections for engaging the well bore wall to aid in centering and aligning the drill string immediately above the drill bit 15.

In FIG. 2 of the drawings, it will be noted that the body 11 is of suitable configuration and includes suitable means such as the threads 11a and 11b for engaging in the drill string and with the drill bit at its lower end, respectively, if desired. A bore 16 extends longitudinally of the body and is adapted to receive valve means shown as being in the form of sleeve means 17. The valve means includes a suitable seat arrangement 18 for receiving and seating a close off tool such as, by way of example only, a sample collector as illustrated in FIG. 3.

The sleeve valve means 17 extends longitudinally of the bore 16, such bore having suitable shoulder means such as 16a for receiving and supporting resilient means 19 therein which abuts adjacent one end as illustrated at 20 of the sleeve valve means 17 for supporting the sleeve valve means 17 in the position as illustrated in FIG. 2 of the drawings. It will be noted that suitable seal means 21, 22, 23, 24 and 25 are provided at spaced intervals between the body 11 and seating sleeve means 17 to seal off therebetween and to assist in controlling communication of various passages in the tool as will be described. The construction and arrangement of the valve means 17 enables it to retain the position illustrated in FIG. 2 of the drawings during normal drilling operations. Similarly, it will be noted that the reinforced inflatable packer means 14 is secured at its upper end 14a to the body 11 and is provided with means represented generally at 26 at its lower end 14b to enable the lower end of the element 14 to move longitudinally relative to body 11 while inhibiting relative rotation therebetween.

The means 26 includes a key 27 carried by the body 11 fitting within the spline 28 formed in the lower end 14b of the resilient element 14. This accomodates relative longitudinal movement of the lower end of annular head 14 of the inflatable element during inflation and deflation thereof while preventing relative rotation between the body 11 and inflatable element 14 while drill pipe is rotating during drilling operations. To aid in retaining the inflatable element in a noninflated position during normal drilling operations and to assist deflation of the inflatable element when the internal pressure is released, the lower end 14b of such member includes spring means 29 which abuts one end of the key 27 and the shoulder 14c formed on the lowermost end of the lower end 14b which tends to extend or retain the element 14 in deflated position and tends to return it to such deflated position upon deflation as will be described in greater detail hereinafter.

The sleeve valve means 17 includes a shock absorbing means referred to generally at 30 which may by of any suitable form and is illustrated as including a plurality of annular elastomer members 31 separated by relatively nondeformable annular members 32, only one of which is illustrated. Such members are provided in the annular recess 11c formed in the body 11 and communicating with bore 16. The upper annular flanged end 17a of the valve means 17 extends into recess 11c as shown. Such shock absorbing means 30 will absorb the shock of a close off tool or a sample collector, both of which function to close off the drill string bore seating on the seat 18 while still accommodating longitudinal movement of the valave means 17.

Control valve means referred to generally at 35 are carried by the body 11 for controlling communication between various passageways in the body 11, and the tool components carried thereby as will be described in greater detail hereinafter.

Resilient means 36 are arranged in the body so as to tend to urge the control valve 35 to the position as illustrated in FIG. 2 of the drawings. In such position, the control valve 35 establishes communication between the well bore annulus and the interior 14d of the inflatable element 14 as well as establishing communication above and below the inflatable element 14 through the equalizing passage means 37 extending longitudinally of the body 11 and communicating at one end 39 with the annular chamber 38 in the body in which the control valve means 35 and the resilient means 24 are carried and at its other end 40 it communicates through the ports 27' with the well bore (not shown) beneath element 14 when the control valve means 35 is in the position shown in FIG. 2.

The annular chamber 38 communicates with the well bore through the ports 41 and 42, such communication being selectively controlled by the control valve means as will be described in greater detail hereinafter.

The annular chamber 38 includes an annular groove 43 as well as the annular groove 44 which are illustrated diagrammatically as being formed in the inner annular surface 38' upon which the control valve means 35 is adapted to slide.

The sleeve valve means 17 includes ports or passageways 47 and 48 which are sealed off from communication with other ports or passage means in the body 11 as well as the control valve means 35 when the seating valve means 17 is in the position as shown in FIG. 2 of the drawings by the seals 21, 22, 23, and 24, respectively.

It will be noted that the control valve means 35 includes the spaced, annular and longitudinally extending recesses 49 and 50 formed on the inner periphery thereof. Spaced seal means 51 and 52 are arranged adjacent one end of the control valve 35 adjacent but spaced from the uppermost end of the annular recess 50 and spaced seal means 53 and 54 are provided on the annular shoulder 55 formed in the annular valve means 35 between the annular recesses 49 and 50. The lower end of the control valve means 35 carries suitable seal means 56 as shown.

When the seating sleeve means 17 is in the position illustrated in FIG. 2 of the drawings, the port means 42 in body 11 communicates at its inner end with the annular groove 57 formed on the outer surface of the seating sleeve means 17. Such annular groove 57 extends beyond annular seal 22 positioned between the seating sleeve means 17 and the body 11 and communicates with the annular groove 58 formed in the body means 11. On the right-hand side of FIG. 2, it can be seen that the annular groove 58 communicates with passage means schematically represented at 59 which, when the control valve 35 is positioned as shown, communicates with the annular recess 50 therein so as to conduct well fluid through the port or passage means 42, the annular groove 57, through communicating annular groove 58, and thence through the passage means 59 to the annular recess 50. It can be appreciated that at the same time fluid from the well bore is conducted through port 41 and into the annular chamber 38 and through the annular groove 43 around seal means 56 into annular recess 49. This communicates the well bore when the control valve 35 is in the position shown in FIG. 2 through annular groove 44 with passage means 60 to the interior 14d of the resilient means 14. With the control valve means 35 positioned as shown in FIG. 2, the annular chamber 38 also conducts such well fluid through the passage 36 to establish communication and equalization above and below the inflatable element 14 in the well bore through the port 27' and port 41.

When the tool is in the foregoing position, normal drilling operations may be continued, and since pressure in the well bore is equalized internally and externally of the inflatable element 14 and thereabove and therebelow, there is substantially no tendency for the inflatable element 14 to inflate, which might destroy or otherwise damage it during rotation of the drill string.

In FIG. 3, suitable means for closing off communication in the longitudinal bore 16 is shown as being in the form of a sample collector 61. The sample collector 61 includes a sample collecting chamber 61' therein which is normally closed off by the valve means represented generally at 62 carried in the chamber 62a of the sampler. Such valve means 62 is provided with a spring 63 for urging the valve towards closed position to close off communication of the passage means 64 and 65 in the sample collector to thereby inhibit entry of fluids into the chamber 61', until desired.

It will be noted that the body of the sampler 61 is provided with an annular shoulder 66' for engaging and seating on the shoulder 18 of the seating sleeve valve means 17, and when this occurs, the resilient means 19 depresses. Also, the upper annular flanged end 17a of the seating sleeve means 17 moves downwardly upon impact of the shoulders 66' and 18 and engages the shock absorbing means 30 which absorbs the shock of the movement of the seating sleeve means and seating of the closure tool when the closure tool such as the sample collector 61 seats therein.

If the weight of the sample collector does not compress the spring 19 to move the seating sleeve means down to the position shown in FIG. 3, then, when the pressure within the drill string represented at 8 is increased slightly, the sleeve 17 will move down whereupon communication between the well bore and annular recess 50 in control valve 35 through port or passage means 42 is closed off. Also, the passage 47 in seating sleeve 17 aligns with annular groove 58 in body 11 which communicates drill string bore pressure around collector 61 through passage means 59 to annular recess 50 internally of control valve means 35, as illustrated in FIG. 3.

Drill string bore pressure is at such time also conducted through the passage means 66 and 67 formed in the sample collector to act on each end of the valve means 62.

Passage means 67 is communicated with drill string bore pressure by means of passage 48 in seating sleeve 17, which has been shifted downwardly from its position shown in FIG. 2, and passage means 68 which communicates at one end with annular recess 50 in control valve 35 and with passage 48 at its other end as shown in FIG. 3.

Seal means 69 and 70 on sample collector 61 seal off between sample collector 61 and seating sleeve means 17 to prevent communication of the drill string bore above the sample 61 and therebelow. The seal means 69 and 70 also span passage means 67 to seal it off for proper communication between recess 50, passage means 68, and passage means 48 when the samper is in the position shown in FIG. 3.

It will be noted that the valve means 62 is provided with suitable seals 71 and 72 adjacent its ends for preventing pressure from the drill string bore on each end of the valve 62 entering chamber 62a. Since the lower end of the valve 62 is provided with the spring means 63, the valve means 62 will retain the position shown in FIG. 3 of the drawings since the fluid pressure from the drill string bore acting on each end of the valve 62 is balanced, and the spring means 63 thus urges the valve to closed position for preventing communication between the passage means 64 and 65 as previously noted.

With the sampler 61 seated as shown in FIG. 3, the port or passage means 41 communicates well bore fluid to annular chamber 38 and thence around seal means 56 on the lower end of the control valve through recess 49 in valve means 35, into annular groove 44, and then passage means 60 to communicate with the interior 14d of inflatable means 14. Also, the annular chamber communicates the well bore fluid through passage means 37 so as to maintain equalization of well bore pressure both above and below the inflatable element as well as interiorly thereof. At this time, it is to be noted that the port or passage means 42 in the body 11 communicating with the well bore annulus is shut off by the seal means 21, 22, and 23.

Thus, well bore pressure above the inflatable element acts on one side of the control valve 38 and drill string pressure acts on the other or inside of the control valve. Thus, the control valve 38 is responsive to the pressure in the drill string above the bore close off means with reference to the pressure in the well bore above the inflatable packer 14.

Since the drill string bore pressure is not communicated interiorly of the control valve 35 and since the cross-sectional area of the control valve across seal means 53 and 54 is larger than the cross-sectional area through the control valve seal means 51 and 52, the control valve means 35 will be responsive to the drill string bore pressure communicated to recess 50 and upon incremental increases of the drill string bore pressure in a predetermined manner the tool may be operated in a sequential, stepwise manner as desired and as will be described hereinafter.

Attention is now directed to FIG. 3A for the next position of control valve means 35. It should be noted at the outset that the resilient means 36 is shown as having been compressed slightly as control valve means 35 moves from the position shown in FIG. 1 to the position shown in FIG. 3A. However, before any movement of control valve means 35 may be accomplished, sufficient drill string bore pressure must be supplied to the recess 50 of the control valve means 35 to overcome the force in resilient means 36. The resilient means 36 may exert any amount of force, and by way of example only, it has been found that when the resilient means 36 exerts a force of approximately 400 pounds per square inch in equivalent hydraulic pressure, a suitable differential between the drill string bore pressure and well bore pressure above the inflated packer means 14 is established to accomplish desired results, as will be noted hereinafter.

In FIG. 3A, a predetermined amount of pressure from the drill string bore is applied through port means 47, passage means 59, and to recess 50 to act on seal means 53 at the lower end of annular recess 50 to move the control valve 35 longitudinally a predetermined distance within annular chamber 38 as illustrated. In this position, fluid from the well bore may flow through port or passage means 41 into the annular chamber 38 and around the seal 56 in the lower end of the control valve 35 to annular groove 43 so that (by referring to FIG. 3), communication is maintained with the end 39 of the passage means 37 for equalizing pressure in the well bore above and below the inflatable means 14. However, seal means 54 on control valve 35 are shown as sealingly engaged with the annular surface 38' of chamber 38, thus closing off communication between chamber 38 and passage 60. This closes off the interior 14d of inflatable member 14 referred to in FIG. 3 to the well bore and opens recess 50 to passage 60 through annular groove 44 so that the packer means 14 may be inflated to seal against the well bore wall.

The next sequence is illustrated in FIG. 3B and shows the control valve 35 as having moved longitudinally an additional predetermined amount in response to an incremental increase in pressure in the drill string bore 16 which is communicated to the recess 50 of the control valve means 35, as previously described. It will be noted that the annular seal means 56 on control valve means 35 is sealingly engaged with the annular surface 38' immediately below annular groove 43 formed in such annular surface 38', thus closing off communication to the groove 43 and thereby closing the equalizing passage 37 which communicates the well bore above and below the inflatable element as described with regard to FIGS. 1, 3, and 3A.

when the control valve 35 is in the position of FIGS. 3A as well as 3B, fluid pressure from the drill string bore 16 is conducted to the interior 14d (FIG. 3) of the inflatable element 14 to effect inflation thereof. Particularly with respect to the position of the control valve 35 shown in FIG. 3B, such pressure is maintained until the inflatable means 14 is inflated and seated in contact with the well bore wall as illustrated in FIG. 4 of the drawings.

As previously described with regard to FIG. 3, as long as annular recess 50 is in communication with passage means 68 in body 11, drill string bore pressure is maintained on the lower end of valve 62 through passage means 68, 48, and 67, and is also maintained on the upper end thereof through passage means 66 and the closing force exerted on the valve 62 is spring 63 acting on the bottom of such valve as diagrammatically illustrated in the drawings. However, as can be seen by referring to FIG. 3, when the control valve 35 continues to move downwardly within annular chamber 38 in response to sequential, incremental pressure increases in a predetermined amount within the drill string bore, the seal ring 52 passes over the passage 68 in body 11 and closes off communication between the drill string bore and such passage as well as the lower end of the valve 62. Thereafter, continued movement of the control valve downwardly within chamber 38 moves seal 51 across the opening of passage means 68 in body 11 so as to communicate chamber 38 therewith and with passage 48 and 67. Chamber 38 is in communication with the well bore by means of port or passage 41 at all times, and thus when seal 51 moves downwardly beneath the opening of passage 68 in body 11, well bore pressure above packer means 14 is communicated to the lower end of the valve 62. Since the pressure within the drill string bore is greater than the pressure within the well bore above packer means 14, the pressure acting through passage 66 of sampler 61 on the upper end of the valve means 62 will thereupon move valve means 62 downwardly to the position as illustrated in FIG. 4 of the drawings.

When this occurs, passage means 64 and 65 within the sample collector 61 are communicated by reason of the reduced stem portion 75 on valve 62 between seals 71 and 76, which reduced stem portion 75 spans the ends of the passages 64 and 65 between the seals 71 and 76 as shown in FIG. 4. When this occurs, the sample collecting chamber 61' is opened to communication through passage 65 and ports 65a in sample collector 61 with the longitudinal bore 16 beneath inflated element 14 and through drill bit 15 to collect a sample of the formation sealed off below the inflated element 14.

It can be appreciated that the sequential operation of the sample valve means 62 in response to the sequential movement of the control valve means 35 insures that the sample valve means 62 will not open for communication of sample collection chamber 61' with the formation below packer means 14 until the inflated means 14 has seated against the well bore wall. This aids in eliminating contamination of the fluids collected from the desired formation below the inflated element 14 by other fluids in the well bore thereabove or by fluids in the drill string bore above the sample collector 61.

The sample collector 61 also includes the pressure recorder 80 therein for recording the pressure of the formation.

The sample collection chamber 61' may be maintained in open position a predetermined interval, say, for example, 20 minutes, and thereafter the control valve 35 may be sequentially moved by incrementally dropping the pressure in the drill string bore to enable the resilient means 36 and well bore pressure above packer means 14 to act against the control valve 35 as illustrated in FIG. 4A of the drawings and move it to its first return position.

Seal means 51 first passes across the end of passage means 68 in body 11 and closes off communication with passage means 67 in sampler 61 and the lower end of the valve means 62 against which the spring 63 acts. Thereafter, seal means 52 passes across the opening of passage means 68 in body 11 so as to communicate annular recess 50 with passage means 68. Since annular recess 50 contains fluid pressure from the drill string bore conducted from above the sampler 61, the drill string bore is at such time again communicated to the lower end of valve 62 through passage means 68, 48, and 67, thereby equalizing the fluid pressure acting on each end of the valve means and then spring 63 functions to move the valve 62 to closed position as shown and described with regard to FIG. 3 of the drawings.

It will be noted by referring to FIG. 4A that when the control valve is in this position, the equalizing passage 37 is still closed off since seal means 56 is still below annular groove 43 formed on the surface 38' of the chamber 38.

However, when control valve means 35 has moved into the position illustrated in FIG. 4B, the seal means 56 is not engaged with surface 38', but is over the annular groove means 43 for communicating the end 39 of the equalizing passage 37 with fluid in the chamber 38 for equalizing pressure in the well bore above and below the element 14 as it deflates.

In some instances, the column of drilling fluid in the well bore annulus surrounding the drill string may become "gassed" or aerated while a formation is being tested. In such event, it is possible that even though the pressure on the drill string fluid column is zero at the earth's surface, the static head in the drill string causes a greater pressure in the drill string adjacent the sample collector than the pressure in the well bore annulus fluid column above the inflated element. Heretofore, it would have been difficult, if not almost impossible to deflate the inflated element under such circumstances; however, the present invention overcomes this problem and enables the inflated element to deflate under substantially any well condition.

More particularly, the present invention is constructed so that the control valve 35 is moved to a position so that the pressure in the well bore annulus above and below the inflated element equalizes even though the pressure in the drill string is in excess of the well bore annulus pressure above the inflated element. The spring 36 forces the control valve 35 to a position to accomplish the foregoing after a test has been completed and while the drill string pressure is being reduced, but while the drill string pressure is still in excess of the well bore annulus pressure. The pressure differential at which this occurs will depend upon the force in spring 36. By way of example only a spring 36 which will function to move the control valve 35 when the drill string pressure exceeds the well bore annulus pressure above the inflated element by approximately 400 psi has been found quite satisfactory to force the control valve for equalizing the pressure in the well bore above and below the element.

A shear safety valve 85 is arranged in body 11 and communicates with passage 60. Should some malfunction occur, the pressure in the drill string can be increased above the pressure at which valve 85 is set to open so that the shear means retaining valve 85 closed will shear and permit it to open.

This communicates the interior 14d of element 14 with the well bore and enables it to deflate.

The sampler 61 of the present invention may be provided with suitable means such as a fishing neck 82 so that a suitable tool, well known in the art, may be lowered into the drill string and engaged therewith for removing the sampler 61.

The sampler 61 may be lowered on a wireline or if desired by reason of the shock absorbing arrangement 30, it may be dropped or pumped down the drill string to seat in the seating sleeve.

From the foregoing description, it can be seen that the control valve functions in response to increasing pressure in the drill string above the bore close off means with reference to the pressure in the well bore above the inflatable packer means 14 to first inflate the packer means 14, then upon further pressure increase, the control valve opens valve 62 so that chamber 61' is open to the well bore below inflated element 14 for receiving a sample.

Then when the pressure in the drill string above the bore close off means is decreased with reference to the pressure in the well bore above the inflatable packer means 14, the valve 62 in sample collector 61 is closed and then upon further decrease in drill string pressure with reference to the pressure in the well bore above the inflatable packer means 14, the inflatable packer is deflated and pressure in the well bore above and below the packer means 14 is equalized with that in the packer means 14.

A check valve 95 is provided in equalizing passage 37 to enable pressure in the well bore beneath packer means 14 to bleed off, if necessary, as packer means 14 is inflated.

In FIG. 5, the position of resilient means 36 and control valve means 35 is reversed from that shown in FIGS. 1 through 4. Such rearrangement necessitates a rearrangement of the passage means 59, 60, 68, and 37, as schematically illustrated in FIG. 5. The other components of the invention are similar to that previously described with regard to FIGS. 1 through 4, and the same reference numbers are applied to FIG. 5 as used in FIGS. 1 through 4.

The function and operation of the form of the invention illustrated in FIG. 5 is similar to that described with regard to FIGS. 1 through 4.

In FIG. 6, the control valve is shown as being of a different form from that in FIGS. 1 through 4, and it will be noted that the control valve 35 is positioned in a valve pocket 38 in the body 11. Again, the passage means 37 as well as the passage means 68 and 48 are rearranged so as to function with the form of the control valve 38 shown in FIG. 6 in a manner similar to that as previously described with regard to the control valve 38 shown in FIGS. 1 through 5. In FIG. 6, the same numbers are applied to the component parts which correspond to those previously described with regard to FIGS. 1 through 4.

The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape, and materials as well as in the details of the illustrated construction may be made without departing from the spirit of the invention.

Claims

What is claimed is:

1. In a tool for running on a drill string in a well bore to seal off the well bore adjacent the tool, the subcombination including:

a. a body for connection in the drill string, said body having a longitudinal bore therethrough;

b. reinforced inflatable packer means carried by said body for inflation to seal off the well bore;

c. bore close off means movable through the drill string for seating in said body; and

d. control valve means carried on said body and having means responsive to well bore pressure and pressure in the drill string whereby said control valve is movable in one direction in response to increasing pressure differential between the drill string above said bore close off means when seated and the well bore above said packer means to communicate said packer means with the drill string for inflation of said packer means and movable in the opposite direction in response to decreasing pressure differential between the drill string above said bore close off means when seated and the well bore above said inflated packer means to communicate said packer means with the well bore for deflation thereof.

2. The invention of claim 1 including means associated with said control valve means to communicate said inflated packer means with the well bore when the pressure in the drill string bore exceeds the pressure in the well bore above said packer means by a predetermined amount.

3. In a tool for running on a drill string in a well bore to seal off the well bore adjacent the tool, the subcombination including:

a. a body for connection in the drill string, said body having a longitudinal bore therethrough;

b. reinforced inflatable packer means carried by said body for inflation to seal off the well bore;

c. bore close off means movable through the drill string for seating in said body;

d. control valve means responsive to the pressure in the drill string above said seated bore close off means with reference to the pressure in the well bore above said inflatable packer for inflation and deflation of said inflatable packer; and

e. valve means in said body normally closing off communication between the body bore and said control valve means.

4. The invention of claim 1 including valve means in said body normally closing off communication between the body bore and said control valve means.

5. The invention of claim 4 including seat means on said valve means in said body for receiving and seating said bore close off means, and there being passage means in said body for communicating the body bore with said control valve means after said bore close off means is seated on said valve means.

6. The invention of claim 4 including means associated with said control valve to communicate said inflatable packer means with the well bore for deflation thereof when the pressure in the drill string above said seated bore close off tool exceeds the pressure in the well bore above said inflatable packer means by a predetermined amount.

7. The invention of claim 3 including shear valve means in said body which will release the inflating pressure from said inflatable packer means when the pressure therein exceeds a predetermined amount.

8. In a tool for running a drill string in a well bore for receiving and seating a sample collector in the drill string to collect a sample from the well bore, the subcombination including:

a. a body for connection in the drill string, said body having a longitudinal bore therethrough;

b. reinforced inflatable packer means carried by said body for inflation to seal off the well bore;

c. means in said body for seating the sample collector to close off the body bore;

d. valve means carried by the sample collector to open and close the sample collector to the well bore below said packer means;

e. control valve means carried by said body for directing fluid after the sample collector is seated to first inflate said packer means and then open said valve means in the sample collector to collect a sample from the well bore and then close said valve means to retain the collected sample in the sample collector; and

f. means normally closing off communication between the body bore and said control valve means until the sample collector is seated in said body.

9. The invention of claim 8 including spring means engaging one end of and normally urging said valve means in the sample collector towards closed position.

10. In a tool for running on a drill string in a well bore for receiving and seating a sample collector in the drill string, the subcombination including:

a. a body for connection in the drill string, said body having a longitudinal bore therethrough;

b. reinforced inflatable packer means carried by said body for inflation to seal off the well bore;

c. means in said body for seating the sample collector to close off the body bore;

d. valve means carried by the sample collector to open and close the sample collector to the well bore below said packer means; and

e. control valve means carried on said body and having means responsive to well bore pressure and pressure in the drill string whereby said control valve is responsive upon increasing the pressure in the drill string above the seated sample collector with reference to the pressure in the well bore above said inflatable packer means to first inflate said packer means and seal off the well bore and responsive upon further increasing the pressure in the drill string above the seated sample collector with reference to the pressure in the well bore above said inflated packer means to actuate said valve means carried by the sample collector to open the sample collector to the well bore below said inflated packer means, and said control valve being responsive upon decreasing the pressure in the drill string above the seated sample collector with reference to the pressure in the well bore above said inflated packer means to first close said valve means in the sample collector and then upon further decrease in the pressure in the drill string above the seated sample collector with reference to the drill pressure in the well bore above said inflated packer means to deflate said inflated packer means.

11. The invention of claim 10 including means associated with said control valve to communicate said inflatable packer means with the well bore for deflation thereof when the pressure in the drill string above said seated bore close off tool exceeds the pressure in the well bore above said inflatable packer means by a predetermined amount.

12. The invention of claim 10 including shear valve means in said body which will release the inflating pressure from said inflatable packer means when the pressure therein exceeds a predetermined amount.

13. In a tool for running on a drill string in a well bore for receiving and seating a sample collector in the drill string to collect a sample from the well bore, the subcombination including:

a. a body for connection in the drill string, said body having a longitudinal bore therethrough;

b. reinforced inflatable packer means carried by said body for inflation to seal off the well bore;

c. means in said body for seating the sample collector to close off the body bore; and

d. control valve means carried on said body and having means responsive to well bore pressure and pressure in the drill string whereby said control valve is responsive upon increasing the pressure in the drill string above the seated sample collector with reference to the pressure in the well bore above said inflatable packer means to first inflate said packer means and seal off the well bore and responsive upon further increasing the pressure in the drill string above the seated sample collector with reference to the pressure in the well bore above said inflated packer means to open the sample collector to the well bore below said inflated packers means and said control valve being responsive upon decreasing the pressure in the drill string above the seated sample collector with reference to the pressure in the well bore above said inflated packer means to first close the sample collector and then upon further decrease in the pressure in the drill string above the seated sample collector with reference to the pressure in the well bore above said inflated packer means to equalize the pressure in the well bore above and below said packer means with the pressure in said packer means and deflate said packer means.

14. The invention of claim 13 including means associated with said control valve to communicate said inflatable packer means with the well bore for deflation thereof when the pressure in the drill string above said seated bore close off tool exceeds the pressure in the well bore above said inflatable packer means by a predetermined amount.

15. The invention of claim 13 including shear valve means in said body which will release the inflating pressure from said inflatable packer means when the pressure therein exceeds a predetermined amount.

16. In a tool for running on a drill string in a well bore for receiving and seating a sample collector in the drill string to collect a sample from the well bore, the subcombination including:

a. a body for connection in the drill string, said body having a longitudinal bore therethrough;

b. reinforced inflatable packer means carried by said body for inflation to seal off the well bore;

c. valve means in said body for seating the sample collector to close off the body bore;

d. valve means carried by the sample collector to open and close the sample collector to the well bore below said packer means;

e. control valve means carried by said body for opening and closing said valve means in the sample collector; and

f. means normally closing off communication between the body bore and said control valve means until the sample collector is seated in said body valve means.

17. In a tool for running on a drill string in a well bore for receiving and seating a sample collector in the drill string to collect a sample from the well bore, the subcombination including:

a. a body for connection in the drill string, said body having a longitudinal bore therethrough;

b. reinforced inflatable packer means carried by said body for inflation to seal off the well bore;

c. valve means in said body for seating the sample collector to close off the body bore;

d. valve means carried by the sample collector to open and close the sample collector to the well bore below said packer means;

e. control valve means carried by said body;

f. means normally closing off communication between the body bore and said control valve means until the sample collector is seated in said body valve means; and

g. said control valve means responsive upon increasing the pressure in the drill string above the seated sample collector with reference to the pressure in the well bore above said inflatable packer means to first inflate said packer means and seal off the well bore and responsive upon further increasing the pressure in the drill string above the seated sample collector with reference to the pressure in the well bore above said inflated packer means to actuate said valve means carried by the sample collector to open the sample collector to the well bore below said inflated packer means, and said control valve being responsive upon decreasing the pressure in the drill string above the seated sample collector with reference to the pressure in the well bore above said inflated packer means to first close said valve means in the sample collector and then upon further decrease in the pressure in the drill string to deflate said inflated packer means.

18. The invention of claim 17 including shock absorbing means supporting said valve means in said body for absorbing shock of seating the sample collector.

19. In a tool for running on a drill string in a well bore for receiving and seating a sample collector in the drill string to collect a sample from the well bore, the subcombination including;

a. a body for connection in the drill string, said body having a longitudinal bore therethrough;

b. reinforced inflatable packer means carried by said body for inflation to seal off the well bore;

c. said body having passage means for communicating with the well bore above and below said packer means;

d. means in said body for seating the sample collector to close off the body bore; and

e. control valve means carried on said body and having means responsive to well bore pressure and pressure in the drill string whereby said control valve is responsive upon increasing the pressure in the drill string above the seated sample collector with reference to the pressure in the well bore above said inflatable packer means to first inflate said packer means and seal off the well bore and responsive upon further increasing the pressure in the drill string above the seated sample collector with reference to the pressure in the well bore above said inflated packer means to open the sample collector to the well bore below said inflated packer means and said control valve being responsive upon decreasing the pressure in the drill string above the seated sample collector with reference to the pressure in the well bore above said inflated packer means to first close the sample collector and then upon further decrease in the pressure in the drill string above the seated sample collector with reference to the pressure in the well bore above said inflated packer means to communicate fluid above and below said packer means through said body passage means and to communicate said packer means with the well bore for deflation thereof.

20. The invention of claim 19 including check valve means in said body passage means to equalize the pressure in the well bore above and below said packer means during inflation thereof.

21. In a tool for running on a drill string in a well bore for receiving and seating a sample collector in the drill string to collect a sample from the well bore, the subcombination including:

a. a body for connection in the drill string, said body having a longitudinal bore therethrough;

b. reinforced inflatable packer means carried by said body for inflation to seal off the well bore;

c. sample collector seating valve means in the bore of said body;

d. control valve means movably mounted in said body; and

e. there being passage means in said body for equalizing the pressure internally of said packer means with the pressure in the well bore above and below said packer means to aid in maintaining said packer means deflated during drilling operations.

22. The invention of claim 21 including means normally closing off communication between the body bore and said control valve means, and there being passage means in said seating valve means and said body for communicating the body bore with said control valve means after the sample collector is seated on said seating valve means.

23. The invention of claim 22 including valve means in the sample collector for opening the sample collector to the well bore below said packer means and for closing the sample collector, there being cooperating passage means in said body, seating valve means, and control valve means for conducting fluid pressure from the drill string to first inflate said packer means and seal off the well bore while communicating drill string pressure to said valve means in the sample collector to act on both ends thereof to aid in maintaining it closed, said control valve means upon further increasing the drill string fluid pressure in relation to the fluid pressure in the well bore above said inflated packer means moving to communicate one end of said valve means in the sample collector to the well bore while communicating drill string pressure against the other end to act on said valve means in the sample collector to open the sample collector to the well bore below said inflated packer.

24. The invention of claim 23 including spring means normally urging said valve means in the sample collector toward closed position and spring means urging said control valve means against the fluid pressure in the drill string whereby decreasing the pressure in the drill string in relation to the fluid pressure in the well bore above said inflated packer means enables said control valve to move and communicate drill string pressure to act on both ends of said valve means in the sample collector and said valve means in the sample collector is closed by said spring means acting thereon.

25. The invention of claim 24 wherein further decreasing the fluid pressure in the drill string in relation to the pressure in the well bore above said inflated packer means communicates passage means in said body and said inflated packer with the well bore for deflation thereof.

26. In a sample collector for use with a well bore tubular string wherein the tubular string has a seating valve means for receiving the sample collector, control valve means for controlling opening and closing of the sample collector, and passage means in the tubular string, seating valve means and control valve means for conducting pressure in the tubular string and well bore for actuating the control valve means, the invention comprising:

a. a sampler body having a sample collecting chamber therein;

b. said sampler body having passage means therein for communicating the sample collecting chamber to collect a sample in the well bore;

c. sampler valve means in said sampler body for controlling communication of the passage means to the sample collecting chamber; and

d. said sampler body having additional passage means for communicating pressure from the tubular string to each side of said sampler valve means when the control valve in the tubular string is in one position to retain said sampler valve means closed and for communicating one side of said sampler valve to the well bore and the other side to the pressure in the tubular string when the control valve is in another position to thereby open the passage means to the sample collecting chamber for collecting a well bore sample.

27. The invention of claim 26 including spring means normally urging said sampler valve means to closed position when both sides of said sampler valve are exposed to tubular string pressure, but movable for opening said sampler valve means when one side of said sampler valve is communicated to the well bore while the other side is communicated to pressure in the tubular string.

28. In an apparatus for obtaining fluid samples from a well bore formation penetrated during the drilling of an oil or gas well or the like with out removing the drill string comprising:

a. a body for connection in the drill string having a longitudinal bore therethrough;

b. reinforced inflatable packer means carried by said body for inflation to seal off the well bore;

c. a sample collector having a sample collecting chamber therein;

d. seating valve means movably mounted in the body bore for receiving and seating the sample collector;

e. control valve means movably mounted in said body for controlling opening and closing of the sample collecting chamber and for controlling inflation and deflation of the inflatable element; and

f. passage means in said body, seating valve means and control valve means for conducting pressure in the drill string and well bore to said control valve for actuation thereof to selectively open and close the sample collecting chamber and to selectively inflate and deflate said packer means.

29. In an apparatus for obtaining fluid samples from a well bore formation penetrated during the drilling of an oil or gas well or the like without removing the drill string comprising:

a. a body for connection in the drill string having a longitudinal bore therethrough;

b. reinforced inflatable packer means carried by said body for inflation to seal off the well bore;

c. a sample collector having a sample collecting chamber therein with passage means for communicating with the well bore below said packer means;

d. seating valve means movably mounted in the body bore for receiving and seating the sample collector;

e. said sample collector being removably inserted in said body and seating valve means and having seal means cooperable with said seating valve means whereby pressure may be built up in the drill string thereabove;

f. valve means movably mounted in said sample collector for opening and closing the collecting chamber passage means to thereby control communication between the sample collecting chamber and well bore;

g. control valve means movably mounted in said body for controlling opening and closing of the collecting chamber passage means and for controlling inflation and deflation of the inflatable element;

h. said body, seating valve means, and control valve means having passage means for conducting pressure in the drill string and well bore to said control valve for actuation thereof to selectively open and close the collecting chamber passage means and to selectively inflate and deflate said packer means;

i. said sample collector having passage means for communicating drill string pressure to both sides of said valve means when said sample collector is seated in said seating valve means to aid in retaining said valve means closed when said control valve means is positioned to communicate drill string pressure to inflate said packer means and seal off the well bore, and thereafter the passage means on one side of said valve means being communicated with the well bore when said control valve means is moved to another position upon increasing the drill string pressure while the passage means on the other side of said valve means is communicated to drill string pressure whereupon said valve means opens to communicate the sample collecting chamber and the well bore below said inflated packer means for collecting a sample in the sample collecting chamber.

30. The invention of claim 29 including seal means between said seating valve means and said body to close the passage means between said body and said control valve means during drilling of the well.

31. The invention of claim 29 including spring means normally urging said valve means in said sample collector toward closed position and spring means urging said control valve means against the fluid pressure in the drill string whereby decreasing the pressure in the drill string enables said control valve means to move and communicate drill string pressure to act on both ends of said valve means in said sample collector while said packer means remains inflated so that said valve means in said sample collector closes the collecting chamber passage means before deflation of said packer means.

32. The invention of claim 31 including passage means in said body which upon further decreasing the fluid pressure in the well bore communicates said inflated packer means with the well bore above and below said packer means for deflation thereof.