US3598191A

US3598191A - Multiple unit well bore sidewall sampler tool

Info

Publication number: US3598191A
Application number: US20655A
Authority: US
Inventors: Luther Bullard
Original assignee: SLIMHOLE SAMPLE SERVICE
Current assignee: SLIMHOLE SAMPLE SERVICE
Priority date: 1970-03-18
Filing date: 1970-03-18
Publication date: 1971-08-10
Anticipated expiration: 1988-08-10

Abstract

A well bore sidewall-sampling tool comprises a casing, adapted to be secured to the end of a drill pipe, and containing a plurality of sample core cutter heads, each of which encases a clear plastic disposable liner tube for receiving and protecting a collected sample of the well bore wall. An actuating mechanism within the casing is operated by fluid pressure applied through the drill pipe. This mechanism includes a rigid operating bar connected to each head for moving each cutter head outwardly into sampling engagement with the sidewall of the well bore when fluid pressure is applied to the casing. The drill pipe is then lifted to cause the heads to bite into the sidewall and cut a sample. A compression spring retracts the sample heads into the casing when the sampling operation is completed.

Description

United States Patent Inventor Luther Ballard Appl. No. 20,655

Filed Mar. 18, I970 Patented Aug. 10, 1971 Assignee Slimhole Sample Service m. y

MULTIPLE UNIT WELL BORE SIDEWALL SAMPLER TOOL 8 Claims, 2 Drawing Figs.

US. Cl 1175/77 lnt. E2lb49/02 Field olSeer-ch 175/77,58, 202, 203

Relerenea Cited UNITED STATES PATENTS 2,013,457 9/1935 Burt 175/77 8/1943 Spencer 175/77 X Primary Examiner-lan A. Calvert Assistant ExaminerRichard E. Favreau Attorney-Drake and Crandell ABSTRACT: A well bore sidewall-sampling tool comprises a casing, adapted to be secured to the end of a drill pipe, and containing a plurality of sample core cutter heads, each of which encases a clear plastic disposable liner tube for receiving and protecting a collected sample of the well bore wall. An actuating mechanism within the casing is operated by fluid pressure applied through the drill pipe. This mechanism includes a rigid operating bar connected to each head for moving each cutter head outwardly into sampling engagement with the sidewall of the well bore when fluid pressure is applied to the casing. The drill pipe is then lifted to cause the heads to bite into the sidewall and cut a sample. A compression spring retracts the sample heads into the casing when the sampling operation is completed.

PATENTED mm 0 I97! INVENTOR [QJTHER BULLARD @fiahu ATTORNEYS MULTIPLE UNIT WELL BORE SIDEWALL SAMPLER TOOL FIELD OF THE INVENTION The present invention relates to an improved sidewall sampler tool for simultaneously obtaining a plurality of wall samples from well bores.

The present invention constitutes an improvement on the well bore sidewall sampler tool disclosed in applicants copending application Ser. No. 889,090, filed Dec. 30, I969, for WELL BORE SIDEWALL SAMPLER TOOL. To the extent necessary for a complete understanding of the within described invention, the disclosure of said copending application is incorporated by reference herein. In summary, the invention disclosed in that application embodies an improved sidewall sampler tool adapted to be secured on the lower end of a drill pipe. The sampler tool includes a tubular casing having a core cutter head pivotally mounted therein. A flexible sample collection receptacle is provided on one end of the core cutter head, while the opposite end of the head includes a spadelike sharpened cutting edge. The core cutter head is actuated to swing outwardly of the easing into sampling engagement with the wall of a well bore by means of a piston and linkage mechanism actuated by the application of fluid pressure to the casing through the drill pipe. The actuating mechanism includes a piston slidably mounted within the easing and biased towards its upper position by a retracting spring. The piston is connected to the core cutter head by a linkage which, when the piston is moved downwardly under the influence of the fluid pressure, swings the core cutter head outwardly into sampling engagement with the wall of the well bore. When the cutter head is extended, the drill pipe stem is then lifted to pull on the sampling tool and cause the core head to dig a sample from the sidewall of the well bore. The sample is collected and retained in the receptacle for later analysis. For a more complete description of the aforesaid apparatus, reference should be made to the aforesaid application.

Various types of multiple unit sample-coring devices have been shown in the art. See, for example, U.S. Pat. No. 2,500,l25, issued Mar. 7, 1950, to T. A. Huber for Sidewall Coring Device"; U.S. Pat. No. 2,334,428, issued Nov. 16, 1943, to L. C. Miller for Well Device; U.S. Pat. No. 2,299,076, issued Oct. 20, l942, to P. T. Bynum for Sidewall Sampler"; U.S. Pat. No. 2,044,648, issued June 16, 1936, to, H. F. Stevens for Sidewall Formation Sampler"; and U.S. Pat. No. 2,013,457, issued Sept. 3, 1935, to C. E. Burt for Apparatus for Extracting Cores from the Sidewall of Well Bores.

OBJECTS OF THE INVENTION It is the principal object of the present invention to provide an improved multiple core unit sidewall sampler tool which is adapted to give substantial representative samples of the material through which the drill hole passes.

Another object of the present invention is to provide a multiple unit tool of the foregoing character which produces a positive sampling action, and in which the sample collected is protected against loss or contamination.

A further object of the present invention is to provide a multiple core unit sample tool in which core-sampling units can be added to or removed from the sampler tool in order to achieve the desired representative samples.

Other objects and advantages of the present invention will become apparent from the following drawings and description of the invention.

SUMMARY OF THE INVENTION The foregoing objects are accomplished by an improved multiple core unit sidewall sampler tool adapted to be secured on the lower end ofa drill pipe. The sampler tool includes a tubular casing having pivotally mounted therein a plurality of core sampler tubes. These tubes are simultaneously actuated to swing outwardly and inwardly of the casing. A power device such as a piston and cylinder mechanism, is coupled to the various cutter units by means of a single rigid linkage system. Upon actuation of the power device, the linkage system swings the cutter tubes outwardly of the easing into sampling engagement with the well bore sidewall. When the cutter heads are extended, the drill pipestem is lifted to pull on the sampling tool and cause the core heads to dig samples from the sidewall of the well bore. These samples are collected in individual removable collection tubes housed within each cutter head. The sample cutter heads are then retracted by a spring or other appropriate device mounted within the casing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an elevation view of a multiple core unit sidewall sampler tool embodying the present invention, with the casing in section to reveal the internal cutter head and linkage mechanism.

FIG. 2 is a view similar to FIG. 1 but substantially enlarged, with portions of the cutter tube mechanism in section, and further illustrating the cutter heads as extended into sampling position.

DESCRIPTION OF THE PREFERRED EMBODIMENT The multiple unit sidewall sampler tool embodying the present invention shown in the drawing comprises a tubular casing 10 housing the samplecutting heads 11 and actuating mechanism indicating generally at 12. The casing is internally threaded at its upper end and adapted to be secured to the lower end of a drill pipestem I4 by an appropriate coupling connector 15. Atits lower end, the casing is enclosed by a bull plug 16. In the embodiment shown, four individual cutter heads II are provided. It will be understood by those skilled in the an that additional heads may be utilized, in keeping with the principal objective of the invention, in order to provide a multiple sampling action. The casing 10, when secured to the lower end of a drill pipestem I4 is lowered into a well bore, indicated generally at 18, for obtaining sidewall samples from the material 19 forming the walls of the bore 18.

The sample cutter heads II are identical, and each sample cutter head comprises a tubular member 20 and a base member 21. The base member 21 is pivotally mounted within the casing 10. A generally rectangular opening 22 is provided in the casing corresponding to each cutter head unit 11, and adjacent to which'the respective cutter head is mounted. For supporting the tubular member 20, each base member 21 is provided with a boss or projection 24 adapted to fit snugly within and support the tubular member or sample tube 20. At its upper end, the tube 20 is provided with a cutting edge 25 for digging a sample from the wall of the well bore. For receiving this sample, a stiff plastic tubular receptacle 26 is inserted and housed within the bore 28 of the tube 20. The bore 28 terminates, at the upper end of the member 20 in a counterbore 29, thereby defining a shoulder 30 against which the upper end of the plastic receptacle 26 seats. The lower end of the plastic receptacle 26 is closed so as to form a cylindrical container which may be readily removed from the tube 20 for retaining and protecting the sample for later analysis.

For swinging the sample cutter heads II in and out of the casing through the openings 22 defined therein, an actuating mechanism [2 is provided. This mechanism is operated to position the cutter beads by any suitable means, one illustrative means shown comprising a fluid pressure system applied to the casing l0 through the drill pipe II. For example, hydraulic fluid pressure in the range of I400 p.s.i. is applied through the drill pipe to the casing to actuate the sampling mechanism. The cutter headactuating mechanism 12 comprises a piston 32 slidably mounted within the casing 10 and having a pair of spaced O-rings or similar seal ring members 34 sealingly engaging the internal surface of the casing 10.

The piston 32 is positioned within the casing above the cutter heads 11 and includes a depending stem 35 which is coupled to a rigid elongated operating bar 36. The operating bar 36 extends throughout substantially the length of the casing l0, and includes elemental sections 38 corresponding to each of the cutter heads 11 joined by lateral sections 39. The respective elemental sections 38 of the operating bar 36 are radially and axially offset to provide space for receiving the cutter heads 11. Also, this structure affords a single rigid operating bar which serves to actuate simultaneously all of the heads inwardly or outwardly of the casing.

Each cutter head is operatively connected with the operating bar 36 by an elongated link 44. The link 44 is pivoted at one end to the adjoining elemental section 38 of the operating bar 36, and at its other end is pivotallyjoined to a rib 45 on the tube of each cutter head.

Provision is made to control movement of the operating bar and thereby determine the extent of outward movement of the cutter head 11 from the casing 10. At its lower end, the operating bar 36 includes a lateral section 39 provided with a depending arm 40 adapted to engage the end of a stop screw 41 threadably engaged in the lower tip end of the bull plug 16 and extending axially within the casing. In order to lift the operating bar 36 to retract the cutter heads, a coil spring 42 surrounds the pin 40 and screw 41 and acts between the bull plug 16 and lateral section 39. When pressure on the piston is released, the spring 42 lifts the operating bar 36, and as will be described below, effects the retraction of the cutter heads ll into the casing.

Prior to the operation of the sampler tool, each cutter head tube 20 is removed from its pivotal mounting member 21, and a plastic sample receptacle 26 is inserted therein. The link 44 provides sufficient slack so that the tubes 20 may be slipped off of their mounting members 21 and readily be thereon replaced. The adjusting screw 41 is then set to provide for the desired extension of the cutter heads ll outwardly from the casing. The casing, with the assembled cutter heads 11 is secured to one end ofa drill pipestem l4 and lowered into the well bore 18 to be sampled. When the desired level is reached for sampling, pressure fluid is supplied through the drill pipestem l4 and acts on the piston 32, pushing the same downwardly. Downward movement of the piston 32 moves the operating bar 36 downwardly until the arm 40 thereon engages the adjusting screw 4l. During this downward movement, the links 44 swing the cutter heads 11 outwardly of the easing into engagement with the sidewall 19 of the well bore 18. The operator then pulls the drill stem 14 upwardly a few inches, during which movement the cutting edge of the cutter heads 11 digs into the well sidewalls l9 and removes a sample which is collected within the sample receptacle 26. When the sampling has been completed, the drill pipe is lowered slightly, fluid pressure is released, and excess pressure fluid escapes through a vent hole 48 in the casing l0. The spring 42 urges the operating bar 36 and piston 32 upwardly, and thereby retracts the cutter heads 11 into the casing 10. The unit can then be removed from the well. Each cutter head tube 20 is then removed, and the sample-containing plastic receptacle 26 are taken out for analysis.

While a certain illustrative embodiment of the present invention has been shown in the drawing and described above in considerable detail. lt should be understood that there is no intention to limit the invention to the specific form disclosed. On the contrary, the intention is to cover all modifications, alternative constructions, equivalents and uses falling within the spirit and scope of the invention as expressed in the appended claims.

lclaim:

l. A well bore sidewall-sampling tool for use on a drill pipe for obtaining sidewall samples from a well bore, comprising a tubular casing adapted to be secured to the end of the drill pipe, a plurality of elongated tubular sample cutter heads swingably mounted at their lower ends in said casing in alternateg opposed positions therein and adapted to be swun outwar ly t rough corresponding openings efined in the wa of said casing for digging a sample from the sidewall of the well bore and to be retracted inwardly through said openings upon the completion of said sampling, and means including a power source for positively extending said cutter heads outwardly from said casing to engage the sidewall of the well bore and dig samples therefrom as the drill pipe is lifted upwardly within the well, characterized by the inclusion therewith of a rigid operating bar longitudinally disposed in said casing and having alternately spaced elemental sections and lateral sections, each elemental section corresponding to a cutter head, and link means operatively connecting each said elemental section with the upper end of a corresponding cutter head whereby axial movement of said bar effects simultaneous outward or inward swinging movement of said cutter heads through the corresponding casing openings.

2. A sampling tool as defined in claim 1 wherein said power means comprises a fluid pressure source and a piston slidably mounted within said casing and means operatively connecting said piston with said operating bar.

3. A sampling tool as defined in claim 1 including spring means between the lower end of said casing and lower end of said bar for lifting said bar to retract the cutter heads operatively connected therewith.

4. A sampling tool as defined in claim 1 wherein each said cutter head includes a clear plastic disposable liner removably mounted therein for receiving and protecting a sidewall sample.

5. In a well bore sidewall-sampling tool for use on a drill pipe for obtaining sidewall samples from a well bore and comprising a tubular casing adapted to be secured to the end of the drill pipe, a plurality of sample cutter heads mounted in said casing and adapted to extend outwardly therefrom through openings defined in the wall of said casing for digging samples from the sidewall of the well bore, means for positively extending said cutter heads outwardly from said casing and means within said casing for positively retracting said cutter heads, the combination therewith of a rigid elongated operating bar longitudinally disposed within said casing and having alternately spaced elemental sections and lateral sections, each said elemental section having a cutter head associated therewith, link means operatively connecting each said elemental section with said associated cutter head, means operatively connecting the upper end of said bar with said extending means, and means operatively connecting the lower end of said bar with said retracting means, whereby axial movement of said bar effects simultaneous outward or inward swinging movement of said cutter heads with respect to said casing.

6. The well bore sidewall-sampling tool as defined in claim 5 wherein said means for positively extending said cutter heads outwardly from said casing comprises a piston slidably and sealingly mounted within said casing and a source of fluid pressure for applying fluid pressure through the drill pipe to said piston and thereby drive said operating bar axially within said casing to swing the cutter heads outwardly ofthe casing.

7. The well bore sidewall-sampling tool as defined in claim 5 wherein said means for positively retracting said cutter heads comprises a spring means acting between the lower end of said casing and said operating bar for lifting said bar and thereby retracting said cutter heads.

8. The well bore sidewall sampling tool as defined in claim 5 including adjustable stop means mounted in the lower end of said casing for limiting engagement with said operating bar to limit the axial movement thereof and thereby adjustably limiting the outward swinging movement of said cutter heads from said Casing.

Claims

1. A well bore sidewall-sampling tool for use on a drill pipe for obtaining sidewall samples from a well bore, comprising a tubular casing adapted to be secured to the end of the drill pipe, a plurality of elongated tubular sample cutter heads swingably mounted at their lower ends in said casing in alternately opposed positions therein and adapted to be swung outwardly through corresponding openings defined in the wall of said casing for digging a sample from the sidewall of the well bore and to be retracted inwardly through said openings upon the completion of said sampling, and means including a power source for positively extending said cutter heads outwardly from said casing to engage the sidewall of the well bore and dig samples therefrom as the drill pipe is lifted upwardly within the well, characterized by the inclusion therewith of a rigid operating bar longitudinally disposed in said casing and having alternately spaced elemental sections and lateral sections, each elemental section corresponding to a cutter head, and link means operatively connecting each said elemental section with the upper end of a corresponding cutter head whereby axial movement of said bar effects simultaneous outward or inward swinging movement of said cutter heads through the corresponding casing openings.

6. The well bore sidewall-sampling tool as defined in claim 5 wherein said means for positively extending said cutter heads outwardly from said casing comprises a piston slidably and sealingly mounted within said casing and a source of fluid pressure for applying fluid pressure through the drill pipe to said piston and thereby drive said operating bar axially within said casing to swing the cutter heads outwardly of the casing.