US3589020A

US3589020A - Air signalling drift apparatus with blow tube

Info

Publication number: US3589020A
Application number: US756083A
Authority: US
Inventors: Wayne M Sullivan; John W Turner Jr
Original assignee: Byron Jackson Inc
Current assignee: Byron Jackson Inc
Priority date: 1968-08-12
Filing date: 1968-08-12
Publication date: 1971-06-29
Anticipated expiration: 1988-06-29

Abstract

An air signalling drift apparatus in which a knob tube is axially shiftable in one direction in a pulse tube when air well drilling fluid circulation is arrested to uncover a number of ports representative of the angle of drift of the drill stem from vertical, through which ports air sequentially passes upon resumption of circulation and the knob tube moves axially in the other direction, to create pressure pulses in the fluid stream detectable at the top of the well and indicative of the angle of drift, and wherein a blowtube is provided to shield the upper end of the knob tube from the accumulation of foreign matter.

Description

Unite States atent Inventors Wayne M. Sullivan;

John W. Turner, ,lr.. both of Houston, Tex. App]. No, 756,083 Filed Aug. 12, 1968 Patented June 29, 1971 Avignon Byron Jackson lnc.. Long Beach,Calif.

('nntinuatiun-in-part ofh'er. Nu. S8l.-l76. Sept. 23. I966. abandoned.

AIR SIGNALLING DRIFT APPARATUS WITH BLOW TUBE 17 Claims, 6 Drawing Figs.

US. Cl 33/205, 175/45 Int. Cl G01c 9/00 Field of Search .t 33/205,

205.5,2055 E; l75/45;73/l52, 155; 166/250 1 a ma [56] References Cited UNITED STATES PATENTS 3,303,573 2/1967 Alder etal. 33/205 Primary Examiner-Leonard Forman.

Assistant Examiner-Steven L. Stephan Attorneys-Donald W. Banner, Lyle S. Motley, C, G Stallings and William S. McCurry ABSTRACT: An air signalling drift apparatus in which a knob tube is axially shiftable in one direction in a pulse tube when air well drilling fluid circulation is arrested to uncover a number of ports representative of the angle of drift of the drill stem from vertical, through which ports air sequentially passes upon resumption of circulation and the knob tube moves axially in the other direction, to create pressure pulses in the fluid stream detectable at the top of the well and indicative of the angle of drift, and wherein a blowtube is provided to shield the upper end of the knob tube from the accumulation of foreign matter.

PATENTEU JUN29 um SHEET 3 OF 3 AIR SIGNAILLING DRIFT APPARATUS WllTlHl BLOW TUBE CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of U.S. application, Ser. No. 581,476, filed Sept. 23, 1966 for an AIR SIGNALLING DRIFT APPARATUS, now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention In the drilling of wells, such as oil and/or gas wells, it sometimes is necessary to determine at intervals the angle of deviation of the well from vertical as the drilling progresses, either for the purpose of maintaining the well as nearly as possible on a vertical axis, or to effect the desired angular deviation ofthe well. Thus, the need arises for signalling drift indicator apparatus capable of periodic operation without undue interruption in the drilling progress.

Signalling drift indicators of the general type here involved are shown in patents heretofore issued to F. M. Varney et al., U.S. Letters Pat. No. 2,435,934, Feb. 10,1948; J. A. Varney, U.S. Letters Pat. No. 2,762,132, Sept. Ill, 1956; and R. L. Alder et al., U.S. Letters Pat. No. 3,176,407, Apr. 6, 1965, as well as in the application for U.S. Letters Pat. filed July 1, 1966, Ser. No. 562,146, in the name of R. Lv Alder, now U.S. Letters Pat. No. 3,457,654, July 29, 1969. As will be recog nized from these prior inventions, pressure pulses or signals may be produced in the stream of drilling fluid adjacent the drill bit and detected or recorded at the earths surface as an indication of the angle of the lower end of the drill string from vertical, such signals being generated in a number which is either directly or inversely related to the angularity of the drill string adjacent the bit. Such devices are of substantial benefit to the proper control of the weight to be applied to the drill bit in order to maintain the desired control over the vertical progression of the drilling operation, as well as being of sub stantial benefit to the driller in determining relative bit effciency, i.e., whether the bit should be changed to enable increased penetration rate at a given depth in the light of the time required to make a round trip of the drill pipe to change bits, all as is now well known in the art.

Heretofore, in the use of devices of the general type discussed above, it has been the practice to cause operation of the signal-producing means in response to the cessation and resumption of the circulation of drilling fluid. In such devices, cessation of drilling fluid circulation allows for upward travel of a flow pressure responsive head or knob through a series of restrictions, and resumption of drilling fluid circulation causes downward travel of the knob through a number of the restrictions related to the angle of the drill string, or more precisely the drill collar sub, in which the knob is disposed. Means are included in such devices which are operative in response to gravity to limit upward travel of the knob in a particular rela tion, which limitation of travel is directly or inversely related to the angle of the sub. However, when air or gas, hereinafter referred to simply as air, is employed as the drilling fluid, the typical pressure pulse producing means which produces clear discriminate signals in a liquid column has been found to be wanting due primarily to the compressibility of the air. When liquid is employed, large clearances between the conventional pulse rings and the traveling knob may be tolerated, but when air is employed the clearances which will permit loss of air should be minimized or controlled to the end that an adequate pressure reduction occurs at spaced intervals as the knob is moved downwardly and alternately pressure builds up sufficiently to produce pressure signals which are clearly distinguishable at the earths surface upon reference to a pressure guage or recorder.

SUMMARY The present invention relates to signalling drift indicators for use in the drilling of boreholes or wells through or into the earth, and more particularly to improvements in the signalproducing means of the instrument whereby it is better adapted to use when gas or air is employed as the drilling fluid.

The present invention provides pressure pulse or signalproducing means for signalling drift indicators particularly adapted for use in drilling operations in which air is employed as the drilling fluid. In accomplishing this, there is provided a pulse tube providing a flow passage through the instrument and having in alternate axially spaced relation a number of ported and unported sections, and cooperative with the pulse tube is a head or knob having an axially extended tube coaxially arranged with the pulse tube, this knob tube having a port arrangement so related to the ported and unported sections or the pulse tube that the ported sections of the latter will be sequentially opened to allow bypass of air around the knob as the knob tube moves axially of the pulse tube, thus producing sequential pressure reductions and rises in the flowing airstream.

More particularly, the invention provides in combination with gravity responsive control means, air pressure pulseproducing means including a knob tube normally biased upwardly within a pulse tube but being forced downward responsive to the circulation of air downward through the tubes, the gravity responsive means being operable to limit upward travel of the knob tube to an extent representative ofthe angular disposition of the drill collar sub in which the instrument is disposed when air circulation is interrupted, and the pulse tube and knob tube having valve means for causing successive pressure cycles or pulses as the knob trube moves downward upon resumption of circulation of the air, the valve means comprising alternate ported and unported sections in one of the tubes and at least one port in the other tube adapted for progressive communication with said ported sections as the knob tube is moved downward, such cycles or pulses resulting in signals which are detectable at the earth s surface as an indication of the angular disposition of the instrument relative to vertical.

A pulse tube and knob tube construction is provided in accordance with the foregoing, wherein the tubes are ported in such a fashion that the same flow area is provided when the ports are aligned or open notwithstanding relative rotation between tee tubes, thus allowing freedom or rotation of the tubes one within the other and eliminating the use of key or other means to assure proper port alignment.

In one embodiment of the invention there is provided a blow tube which shields the structure from the accumulation of adverse deposits of such matter as water, grease from tool joint connections, dirt from the drill pipe, bits of wood splinters, sulfur from gas, or the like which have been found to cause deposits varying from gummy consistency to firm flaky material. More particularly, the blow tube is disposed in the knob tube and provides a shield means for preventing the accumulation of such deposits above the shoulder inherently provided at the upper end of the knob tube, either on such shoulder or on the interior cylindrical wall of the pulse tube.

Accordingly, an object of the invention is to provide pressure pulse or signal-producing means for signalling drift indicators particularly adapted for use in drilling operations in which air is employed as the drilling fluid. In accomplishing this objective there is provided a pulse tube providing a flow passage through the instrument and having in alternate axially spaced relation a number of ported and unported sections, and cooperative with the pulse tube is a head or knob having an axially extended tube coaxially arranged with the pulse tube, this knob tube having a port arrangement so related to the ported and unported sections of the pulse that the ported sections of the latter will be sequentially opened to allow bypass of air around the knob as the knob tube moves axially of the pulse tube, thus producing sequential pressure reductions and rises in the flowing airstream, but the pulse tube and knob tube being shielded by a blow tube to prevent accumulation of deposits at the upper end of the knob tube.

Other objects and advantages of the invention will be hereinafter described or will become apparent to those skilled in the art, and the novel features of the invention will be defined in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing a drill collar sub broken away to expose in longitudinal section an instrument made in accordance with the invention with the knob tube depressed by the downward flow of air through the instrument;

FIG. 2 is a fragmentary view in longitudinal section, showing the pulse-producing means of the invention in one position of limited upward movement of the knob tube upon interrup tion of the downward flow of air through the instrument;

FIG. 3 is a fragmentary view showing the pulse tube and knob tube of FIG. 2 with ports open in response to resumption of the downward flow of air through the instrument and downward movement of the knob tube;

FIG. 4 is an enlarged transverse sectional view as taken on the line 4-of FIG. 3;

FIG. Sis a view generally corresponding to FIG. 2 but showing a modified embodiment of the invention; and

FIG. 6 is a fragmentary view showing the pulse tube and knob tube of FIG. 5 with the ports closed in response to re sumption of the downward flow of air through the instrument and downward movement of the knob tube.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIG. 1, there is shown an instrument made in accordance with the invention and disposed in a drill collar sub C, having a body 1, pin end 2, and a box end 3 for threaded connection in the drill string. Pin end 2 is formed on a cap 4 which is suitably removably connected to the body 1 as by a thread (not shown) whereby the instrument may be in stalled in the body 1. This instrument includes a pulse or signal producing section P and a shaft and pendulum section S. The latter section 5 includes a housing 5 and at the lower end of which is a bottom support 6 in the form of a spider providing flow passages 7, this bottom support seating on a shoulder 8 at the bottom of drill collar body 1. Housing 5 of section S is connected by a spider 9 having flow passages R0 to a pulse section P, and the pulse section P includes a housing ll which extends upwardly in the drill collar body 1 and is provided with an upper flange 12. Above flange 12 is a pair of resilient packing rings 13 engaged by the lower end of a spacer sleeve 14 extending upwardly for engagement with the cap 4, whereby the entire instrument assembly is adapted to be held in place in collar body 1 and seated on shoulder 8 at the bottom support 6.

The pulse-producing section P includes a stationary member or pulse tube 15 welded as at 16 to the flange 12 of the housing 11 or otherwise integral with the housing 11. At its upper end the pulse tube 15 is provided with debris catcher means in the form ofa ring 17 retained in tube 15 by snaprings l8 and having a number of crossed pins 19 or other obstructions to the downward passage of debris. In spaced relation axially of the pulse tube 15 are alternate ported sections having ports 20 and unported sections 21. The ports 20 lead from the central flow passage through the pulse tube 15 into the annular space 22 formed between the pulse tube 15 and the housing 11.

Reciprocably disposed within the pulse tube 15 is a movable member or knob tube 23 of such a length as to extend upward in the pulse tube 15 to a location above the uppermost of the ports 20 when the inner knob tube 23 is in the lowermost posi' tion, as shown in FIG. 1, thus closing all of the ports 20. In the inner knob tube 23 and below the lower extremity of the pulse tube 15, when the inner knob tube 23 is in said lowermost position of FIG. 1, is a number of knob tube ports 24, including in the illustrative embodiment a pair of axially spaced sets of ports 24, these sets of ports 24 being axially spaced a distance corresponding to the axial distance between pulse tube ports 20 to enable alignment of

ports

20 and 24 when the inner knob tube 23 is moved upwardly into the pulse tube 15. At its lower end, the knob tube 23 is connected to a knob 25. Suitable sealing means 26 are provided between the knob tube 23 and knob 25 and a snapring 27 or other suitable means are employed for connecting the knob tube 23 to the knob 25.

It is notable that with the knob 25 in the position shown in FIG. ll. i.e., in its lowermost position, the ports 24 in knob tube 23 provide a path for the flow of air downward through the pulse tube 15 and knob tube 23 and out into the annular space 22 previously referred to. Thence, such air may flow downward through spider openings 10, along the outside of the shaft and pendulum section S of the instrument, and openings 7 in bottom support 6. Such flow of air will hold the knob 25 and the knob tube 23 in the depressed position of FIG. 1.

Shaft and pendulum section S includes within its housing 5 a shaft 30 which extends through the upper end of housing 5 and is connected to the knob 25. Within the housing 5 is a mainspring 31 which provides a force normally tending to push the shaft upwardly. Means are provided within the housing 5 for limiting upward movement of shaft 30 a distance related to the angle of drift of the drill collar sub C and the well from vertical so that upward movement of knob 25 will be correspondingly limited. As seen in FIG. 1, this means comprises a pendulum 32 pivotally supported beneath shaft 30 by bail means 33 and having a head 34 providing a shoulder which is selectively engageable with one of a plurality of axially spaced annular stops 35 of progressively diminishing diameter. It will be recognized that the angular disposition of the drill collar sub C relative to the pendulum 32, which, being gravity responsive will depend vertically from its pivot, will determine which stop 35 will be engaged by pendulum head 34, and that while in the structure shown the permitted upward travel of the pendulum and the shaft is inversely related to the angular disposition of the body I, i.e., the greater the angle the less the travel, the assembly may include a coding system for enabling a direct relationship between angle and extent of shaft travel, as disclosed in the aforesaid U.S. Letters Pat. No. 3,176,407.

In either event, downward movement of the knob 25 and connected knob tube 23 responsive to flow of drilling fluid or air through

certain ports

24 and 20 will cause the production of a pressure signal in the stream of air which is detectable at the earths surface for purposes of indicating the angle of the drill collar sub C. In order that the pulses will be of sufficient duration so as to be easily discriminated from normal pressure variations in the fluid stream, a clean body of oil in the shaft and pendulum section S is displaced through an orifice assembly including a number of orifice discs 36 which are disposed in a passage 37 in a combined disc support and pendulum seat 39 which is mounted in the housing 5 between rings 40. A bypass passage 41 and a downwardly closing check valve 42 are provided in the support 39 for allowing relative freedom of upward movement of instrument fluid in housing 5 through support 3Q during upward movement of shaft 35).

This clean oil or instrument fluid is retained in the housing 5 by means of a seal ring 43 which is interposed between the upper end of housing 5 and the shaft 30 and by a pressure equalizing divider below the support 39. The divider in the illustrative embodiment is in the form ofa diaphragm 44, but a free piston may also be employed.

Referring now to FIGS. 2 through 4, the details of the illus trative embodiment of the pulse or signal-producing section P of the invention will now be described with greater particularity as regards the valve action of the

tubes

15 and 23.

In fig. 2 the knob 25 and knob tube 23 have moved upward from the position shown in FIG. I, as would occur upon interruption of the downward flow of air through the drill string,

ward movement of the knob is limited by the pendulum 32 which engages one of the stops 35 and thereby determines the limit of upward travel of shaft 30 as a function of the angular disposition of drill collar sub C relative to vertical. The knob tube ports 24 and pulse tube ports 20 are spaced in this embodiment such that when pendulum head 34 is engaged with any one of the annular stops 35 the knob tube ports 24 are opposite unported sections 21 of the pulse tube 15. Thus, when airflow into the drill string is resumed, a minimum of air will bypass the pulse-producing means as pressure is developed therein. When the pressure reaches a level at which a force is produced acting downwardly on the knob 25 and knob tube 23 to overcome the upwardly acting force of mainspring 31, the knob and knob tube will move downward to the position shown in FIGS. 3 and 4, at which position knob tube ports 24 are in registry with one set of pulse tube ports 20, at which time the air pressure will drop as air flows through the registered ports, as shown by the arrows in FIG. 4. Then, the knob and knob tube will continue to move downward due to pressure acting on the knob until the knob tube ports are op posite a lower unported section 21 of the pulse tube 15, thereby causing an increase in pressure and completing a full pressure cycle which is reflected in the body of air in the drill string as a detectable and recordable pressure pulse. Obviously, the number of pulses thus produced will be indicative of the number of unported sections 21 of the pulse tube traversed by the ports 24 of the knob tube 23, as the latter moves downward, the extent of such travel depending upon the extent of initial upward travel of the knob 25 under the limiting control of the gravity responsive pendulum.

It will be appreciated from the foregoing that the flow area through the

ports

20 and 24 when they are in registry should be large enough to allow a substantial drop in pressure as compared with the pressure when the knob ports 24 are opposite unported pulse tube sections 21, so that a discrete pressure signal will be produced, but yet it is necessary that this flow area be sufficiently restricted as to not bleed off air to such an extent as to negate the continued downward movement of the knob 25 and knob tube 23 against the counterforce of mainspring 31. Since the airflow conditions may vary in different drilling operations, it is apparent that the detachable connection of the knob tube 23 to the knob tube 25 enables substitution of knob tube 23 with various port arrangements as may be found necessary or desirable in relation to a given pulse tube port arrangement. However, the arrangement shown in detail in FIGS. 2 through 4 has been found to be quite satisfactory in terms of reliable production of discrete pressure signals at the earths surface. In this connection, it is notable that the pulse tube ports 20 and the knob tube ports 24 are respectively in the form of elongated slots extended circumferentially of the respective tubes and interrupted by tube sections a and 2311 (FIG. 4) spaced 120 apart, the ports having a greater angular extent than sections 23a, and the ports 24 having a greater angular extent than the sections 1511. Therefore, as indicated above, the relative orientation of the

tubes

15 and 23 about their common longitudinal axis is immaterial to the net flow area through the ports when they are in registry.

Referring to FIGS. 5 and 6, a modified construction is illustrated.

As seen in these FIGS. of the drawings, it will be noted that the upper extremity 23b of the knob tube 23 provides a ledge or shoulder slidable within the cylindrical bore of the pulse tube 15 which, if exposed to the flow of air downwardly therethrough, would be subject to the accumulation of deposits thereon of any foreign matter entrained in the air, such as mud, dirt, grease from the drill pipe tool joints, wood splinters, sulfur from gas, or the like. Ifdrilling progresses for a prolonged period without lIltCl'lL lllOl'l such deposits may be substantial if allowed. However, in accordance with the present invention no such accumulation of deposits can occur. To avoid this problem the invention provides a tubular member 17a, which may be characterized as a blow tube. This blow tube 170, as seen in FIG. 5, has its lower extremity ex tending into the upper end of the knob tube 23, when the knob tube is in its lowermost position, The blow tube 17a provides shielding means for the shoulder or ledge 23b on the knob tube 23 protecting tee ledge 23b and the bore of the pulse tube I5 from the flow of air.

Suitable means are provided for supporting the blow tube in position, and, in the illustrative embodiment, the tube is formed as an integral cylindrical downward extension of the debris catcher ring l7. Since the inside diameter of the blow tube I7a is less than the inside diameter of the knob tube 23, and is elongated so as to form a nozzle the velocity of air traveling through the assembly is increased, thus tending to reduce the likelihood of deposits, as aforesaid, forming in the knob tube ports 24.

Thus, the blowtube 17a has the dual function of forming means for shielding the end 23 of the knob tube and the bore of the pulse tube 15 from the airstream as well as providing nozzle means for increasing the velocity of airflow in advance of flow through the knob tube ports 24.

In the embodiment of the invention as shown in FIGS. 1 through 4, as previously described, the ports 24 in the knob tube 23 and the ports 20 in the pulse tube 15 are so relatively axially spaced that when the upward movement of the shaft 30 is arrested responsive to engagement of the head 34 of the pendulum 32 with one of the stop shoulders 35, the ports 24 will be located between the ports 20, as seen in FIG. 2. In the modified construction as shown in FIGS. 5 and 6, the relative axial spacing of the

ports

24 and 20 in the knob tube 23 and the pulse tube 15, respectively, and the limit of upward travel of the knob tube 23 are arranged so that the knob tube ports 24 are aligned or in communication with the pulse tube ports 20 when the head 34 of the pendulum .32 engages one of the stop shoulders 35, as is illustrated in FIG. 5. This modified arrangement of the

ports

24 and 20 is such that the initial pressure cycle will be of greater magnitude: and more readily detectable at the top of the well than is the case with the first described embodiment in which the

ports

24 and 20 are out of registry when upward movement of the knob tube 23 is arrested. In this connection it will be understood that when the drilling fluid is a compressible fluid, such as air, the flow of air through the communicating

ports

20 and 24, as shown in FIG. 5, will cause a gradual in crease in the air pressure in the drill string above the instrument due to the pressure loss through the

ports

20 and 24. Therefore, the pressure acting to move the knob tube 23 downwardly builds up gradually until such pressure is of sufficient magnitude as to effect downward movement of the knob tube causing closure of the ports 20, resulting in an immediate substantial increase in pressure which is rapidly bled off when the

ports

24 and 20 are next registered. Thus there is produced an initial pressure pulse of greater magnitude than will be produced when the

ports

24 and 20 are in the starting relationship shown in FIG. 2.

While the specific details of the invention have been herein shown and described, changes and alterations may be resorted to without departing from the spirit of the invention.

We claim:

I. In signalling drift apparatus comprising: an elongated tubular body adapted to be installed in a well-drilling string and having a passageway therethrough for the flow of drilling fluid, pulse-producing means in said passageway including a movable member exposed to the flow of drilling fluid and held in a first position responsive to said flow, means for effecting movement of said movable member from said first position to another position related to the angular disposition of said body upon interruption of the flow of drilling fluid, and a stationary member for effecting a number of pulses in said drilling fluid as said movable member returns to said first position upon resumption of said flow; the improvement wherein one of said members is provided with a series of opens therethrough and the other of said members is provided with at least one opening therethrough, said at least one opening being progressively cooperative with said series of openings to allow the passage of drilling fluid through said passageway when said at least one opening is aligned with one of said series of openings, and to prevent the passage of drilling fluid when said at least one opening is not aligned with one of said series of openings.

2. Signalling drift apparatus as defined in claim 1, wherein said members respectively are in the form of a pair of tubes, one tube being coaxially disposed with the other.

3. Signalling drift apparatus as defined in claim 2, wherein the openings of each of said tubes are formed by circumferentially extended slots, said tubes having unslotted sections intermediate the ends of the slots, said slots being longer than said unslotted sections.

4. Signalling drift apparatus as defined in claim 1, wherein the means for effecting movement of said movable member from said first position includes a spring and gravity responsive stop means for limiting said movement of said movable member to an extent related to the angular disposition of said body.

5. Signalling drift apparatus as defined in claim 1, wherein said means for effecting movement of said movable member from said first position includes a shaft, said movable member being connected to said shaft, a spring acting on said shaft and normally biasing the same to move said movable member, gravity responsive stop means for limiting the extent of said movement of said movable member from said first position, said movable member including a tube extending longitudinally in said passageway and said stationary member also including a tube extending longitudinally in said passageway in coaxial relation with said movable tube, at least one opening said tubes and said series of being in said tubes.

6. Signalling drift apparatus as defined in claim 1, wherein said movable member comprises a longitudinally extended tube having said at least one opening therein, said stationary member comprising a tube coaxial with said movable tube and having said series of openings spaced axially therealong.

7. Signalling drift apparatus as defined in claim 6, wherein said movable tube has a section without openings that extends along said stationary tube and has an axial length greater than the total axial length of the series of openings sections of said stationary tube for closing the openings of all of said series of openings of said stationary tube when said movable tube is in said first position.

8. Signalling drift apparatus as defined in claim 1, including means for shielding said tubes from the deposit of foreign matter thereon.

9. Signalling drift apparatus as defined in claim 8, wherein said means for shielding also provides nozzle means for increasing the velocity of air flow through said movable member.

10. Signalling drift apparatus as defined in claim I, wherein said members respectively are in the form of tube members, one tube member being coaxially disposed within the other tube member, and including means for shielding said tubes from the deposite of foreign matter thereon comprising a blowtube extending coaxially into the inner of said tube members.

ll. Signalling drift apparatus as defined in claim 1, wherein said members respectively are in the form of tube members, one tube member being coaxially disposed within the other tube member, said series of openings and said at least one opening being provided in said tube members and being in the form of circumferentially extended axially spaced slots, and including means for shielding said tubes from the deposit of foreign matter thereon comprising a blowtube extending coaxially into the inner of said tube members to a point spaced from the nearest slot.

12. Signalling drift apparatus as defined in claim 1, wherein said means for effecting movement of said movable member from said first position includes a shaft, said movable member being connected to said shaft, a spring acting on said shaft and normally biasing the same to move said movable member, gravity responsive stop means for limiting the extent of said movement of said movable member from said first position, said movable member including a tube extending longitudinally in said passageway and said stationary member also including a tube extending longitudinally in said passageway in coaxial relation with said movable member, said series of openings being in said tubes, and including means for shielding said tubes from the deposit of foreign matter thereon comprising another tube extending axially into said tube of said movable member.

13. Signalling drift apparatus adapted to be disposed in an elongated drill collar sub, comprising: an elongated housing having a body of clean fluid therein, a divider movably disposed in one end of said housing, a shaft reciprocable in said housing and having an end projecting from the other end of said housing, means for effecting a seal between said shaft and said housing, a spring in said housing acting on said shaft for causing said shaft to be moved outward with respect to said housing, gravity responsive stop means in said housing for limiting outward movement of said shaft to an extent related to the disposition of said housing relative to vertical, pulse tube means carried by said housing, a knob on said end of said shaft, knob tube means on said knob and extending axially into said pulse tube means, said pulse tube means and said knob tube means together operatively defining valve means progressively openablc and closable in response to movement of said knob tube means axially in said pulse tube means, a blowtube, means supporting said blowtube in coaxial relation to said pulse tube means and said knob tube means with the lower end of said blowtube telescopically fitting within said knob tube means.

14. In signalling drift apparatus comprising: an elongated tubular body adapted to be installed in a well drilling string and having a passageway therethrough for the flow of drilling fluid, pulse-producing means in said passageway including a movable member exposed to the flow of drilling fluid and held in a first position responsive to said flow, means for effecting movement of said member from said first position to another position related to the angular disposition of said body upon interruption of the flow of drilling fluid, and a stationary member for effecting a number of pulse in said drilling fluid as said movable member returns to said first position upon resumption of said flow; the improvement wherein said stationary member comprises an elongated tube in said passageway, and said movable member comprises an elongated tube coaxial with said stationary tube, one of said tubes having alternately in axially spaced relation therealong a series of openings connecting said passageway in said stationary tube with the passageway below said stationary tube, said movable tube having at least one opening movable successively past said series of openings of said stationary tube.

15. Signalling drift apparatus as defined in claim 114, wherein said movable tube includes a pair of axially spaced openings spaced a distance equal to the spaces between adjacent openings of said series of openings of said stationary tube for registry with the adjacent openings of the latter.

l6. Signalling drift apparatus as defined in claim 15, wherein said openings of each of said tubes are formed by circumferentially extended and circumferentially spaced said slots being longer circumferentially than the spacers therebetween.

l7. Signalling drift apparatus adapted to be disposed in an elongated drill collar sub, comprising: an elongated housing having a body of clean fluid therein, a divider movably disposed in one end of said housing, a shaft reciprocable in said housing and having an end projecting from the other end of said housing, means for effecting a seal between said shaft and said housing, a spring in said housing acting on said shaft for causing said shaft to be moved outward with respect to said housing, gravity responsive stop means in said housing for limiting outward movement of said shaft to an extent related to the disposition of said housing relative to vertical, pulse tube means carried by said other end of said housing and extending axially therefrom, a knob on said end of said shaft, knob tube means on said knob and extending axially into said pulse tube means, said knob tube means and said pulse tube opening in the other of said tube means, and said other tube means having a section without openings for closing all of said series of openings of said one of said tube means upon inward movement of said shaft to its innermost position.

mg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 ,5 9: Dated June 99: 97

fl Wayne M. Sullivan and John W. Turner, Jr.

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 2, line 17, "or" should be --of----;

line M7, "tee" should be --the--;

"or" should be --of.;...; line 7'2, after "pulse" insert --tube--. Col. 3, line 2 4, L should be L-4--. Col. 6, line "tee" should be --the---;

line 71 (line 13 01? claim 1), "opens" should be --openings--.

Col. 7, line 6 (line 3 of claim 2) "with" should be --within--;

lines 29 and 30 (lines ll and 12 of claim 5), cancel "at least one opening said tubes and said series of being in said tubes" and insert --said at least one opening and said series of openin '5: being in said tubes--;

line 39 line i of claim 7), cancel "sections"; Q line 55 line 5 of claim 10) "deposits" should be ---deposit--.

Col. 8, line 39 (line 10 of claim 1%) "pulse" should be --pulses--; line 58 (line 3 of claim 16), after "spaced" insert --slots,--.

Signed and sealed this 11th day of January 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Acting Commissioner of Patents J

Claims

1. In signalling drift apparatus comprising: an elongated tubular body adapted to be installed in a well-drilling string and having a passageway therethrough for the flow of drilling fluid, pulse-producing means in said passageway including a movable member exposed to the flow of drilling fluid and held in a first position responsive to said flow, means for effecting movement of said movable member from said first position to another position related to the angular disposition of said body upon interruption of the flow of drilling fluid, and a stationary member for effecting a number of pulses in said drilling fluid as said movable member returns to said first position upon resumption of said flow; the improvement wherein one of said members is provided with a series of opens therethrough and the other of said members is provided with at least one opening therethrough, said at least one opening being progressively cooperative with said series of openings to allow the passage of drilling fluid through said passageway when said at least one opening is aligned with one of said series of openings, and to prevent the passage of drilling fluid when said at least one opening is not aligned with one of said series of openings.

2. Signalling drift apparatus as defined in claim 1, wherein said members respectively are in the form of a pair of tubes, one tube being coaxially disposed within the other.

10. Signalling drift apparatus as defined in claim 1, wherein said members respectively are in the form of tube members, one tube member being coaxially disposed within the other tube member, and including means for shielding said tubes from the deposite of foreign matter thereon comprising a blowtube extending coaxially into the inner of said tube members.

11. Signalling drift apparatus as defined in claim 1, wherein said members respectively are in the form of tube members, one tube member being coaxially disposed within the other tube member, said series of openings and said at least one opening being provided in said tube members and being in the form of circumferentially extended axially spaced slots, and including means for shielding said tubes from the deposit of foreign matter thereon comprising a blowtube extending coaxially into the inner of said tube members to a point spaced from the nearest slot.

13. Signalling drift apparatus adapted to be disposed in an elongated drill collar sub, comprising: an elongated housing having a body of clean fluid therein, a divider movably disposed in one end of said housing, a shaft reciprocable in said housing and having an end projecting from the other end of said housing, means for effecting a seal between said shaft and said housing, a spring in said housing acting on said shaft for causing said shaft to be moved outward with respect to said housing, gravity responsive stop means in said housing for limiting outward movement of said shaft to an extent related to the disposition of said housing relative to vertical, pulse tube means carried by said housing, a knob on said end of said shaft, knob tube means on said knob and extending axially into said pulse tube means, said pulse tube means and said knob tube means together operatively defining valve means progressively openable and closable in response to movement of said knob tube means axially in said pulse tube means, a blowtube, means supporting said blowtube in coaxial relation To said pulse tube means and said knob tube means with the lower end of said blowtube telescopically fitting within said knob tube means.

14. In signalling drift apparatus comprising: an elongated tubular body adapted to be installed in a well drilling string and having a passageway therethrough for the flow of drilling fluid, pulse-producing means in said passageway including a movable member exposed to the flow of drilling fluid and held in a first position responsive to said flow, means for effecting movement of said member from said first position to another position related to the angular disposition of said body upon interruption of the flow of drilling fluid, and a stationary member for effecting a number of pulses in said drilling fluid as said movable member returns to said first position upon resumption of said flow; the improvement wherein said stationary member comprises an elongated tube in said passageway, and said movable member comprises an elongated tube coaxial with said stationary tube, one of said tubes having alternately in axially spaced relation therealong a series of openings connecting said passageway in said stationary tube with the passageway below said stationary tube, said movable tube having at least one opening movable successively past said series of openings of said stationary tube.

15. Signalling drift apparatus as defined in claim 14, wherein said movable tube includes a pair of axially spaced openings spaced a distance equal to the spaces between adjacent openings of said series of openings of said stationary tube for registry with the adjacent openings of the latter.

16. Signalling drift apparatus as defined in claim 15, wherein said openings of each of said tubes are formed by circumferentially extended and circumferentially spaced said slots being longer circumferentially than the spacers therebetween.

17. Signalling drift apparatus adapted to be disposed in an elongated drill collar sub, comprising: an elongated housing having a body of clean fluid therein, a divider movably disposed in one end of said housing, a shaft reciprocable in said housing and having an end projecting from the other end of said housing, means for effecting a seal between said shaft and said housing, a spring in said housing acting on said shaft for causing said shaft to be moved outward with respect to said housing, gravity responsive stop means in said housing for limiting outward movement of said shaft to an extent related to the disposition of said housing relative to vertical, pulse tube means carried by said other end of said housing and extending axially therefrom, a knob on said end of said shaft, knob tube means on said knob and extending axially into said pulse tube means, said knob tube means and said pulse tube means having valve means progressively openable and closable in response to movement of said knob tube means axially in said pulse tube means, said valve means includes a series of axially spaced openings in one of said tube means, at least one opening in the other of said tube means, and said other tube means having a section without openings for closing all of said series of openings of said one of said tube means upon inward movement of said shaft to its innermost position.