|Publication number||US2492794 A|
|Publication date||Dec 27, 1949|
|Filing date||Aug 28, 1944|
|Priority date||Aug 28, 1944|
|Publication number||US 2492794 A, US 2492794A, US-A-2492794, US2492794 A, US2492794A|
|Inventors||Goble Ralph W, Gordon Jackson|
|Original Assignee||Eastman Oil Well Survey Co|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (22), Referenced by (20), Classifications (19)|
|External Links: USPTO, USPTO Assignment, Espacenet|
Dec. 27, 19 R. GOBLE Er AL, 2,492,794
METHODS OF AND APPARATUS FOR TRANSMITTING INTELLIGENCE TO THE SURFACE EROM WELL BORES Filed Aug. 28, 1944 5 Sheets-Sheet l Eel 7h 14 Gob/e Cvoraorz Jack 50/? INVENTORS ATTORNEY.
Dec. 2?, 1949 R. w. GOBLE ET AL 2,4923%4 METHODS OF AND APPARATUS FOR TRANSMITTING INTELLIGENCE TO THE SURFACE FROM WELL BORES Filed Aug. 28, 1944 5 Sheets-Sheet 3 Ba! /2 71 Gob/e 6 Gorgon Jackson INVENTOR5 ATTORNEY.
27, 1949 R. w. GOBLE El AL METHODS OF AND APPARATUS FOR TRANSMITTING INTELLIGENCE TO THE SURFACE FROM WELL BORES v v Filed Aug. 28, 1944 5 Sheets-Sheet 4 Raf 0k I44 Gob/e Gordon Jackson INVENTORS 1M ATTORNEY.
Dec. 27, 1949 Filed Aug. 28, 1944 ET AL FOR TRANSMITTING INTELLIGENCE TO THE SURFACE FROM WELL BORES 5 Shets-Sheet 5 mmggz afl BY j ATTORNEY.
Patented Dec. 27, 1949 UNITED STTES OFFE r 2,492,794 METHODS or AND APPARATUS FOR TRANS- MITTING INTELLIGENCE TO THE SUB- FACE FROM WELL BOBES corporation of Delaware Application August 28, 1944, Serial No.- 551,570
This invention relates to new and useful improvements in methods of and apparatus for igransmitting intelligence to the surface from well ores.
As is well known, the drilling of wells for the recovery of petroleum products requires many and varied operations which involve the use of different types of apparatus and tools. Such apparatus and tools must at all times be under the operators control and also information rearding the well bore being drilled, such as its 11 Claims. (01. 250-2) given by the instrument is particularly disadvantageous where various well tools are to be oriented and set within the well bore for manifestly, all rig operations are held up while the diameter, its degree of inclination, the direction 7 of inclination, etc., must be known in order that proper drilling procedure may be carried out. The usual drilling operations involve the use and setting of whipstocks, deflecting tools and other equipment which devices must be properly oriented within the well bore to accomplish the desired results. Thus, it becomes apparent that much information regarding the position of tools and devices, the size, degree and direction of the well bore and other data must be made available to the drilling operator to permit him to drill the well bore in the desired manner.
Various methods of transmitting the necessary information to the surface have been in general use and up to the present time probably the most desirable and'efiicient of these involves the use of various types of photographic instruments. With reference to the informationregarding the well bore, instruments incorporating a compass and an inclination indicator with means for photographing the relative positions thereof are in wide-spread use for determining direction and degree of inclination of a well bore. The diameter of the bore is determined by mechanical well calipers which are lowered through said here and which engage the wall thereof to measure the same. With respect to the orientation and setting of tools, such as whipstocks, photographic types of instruments have been utilized to gain the desired information regarding the position of said tools; in some instances, methods involving instruments other than photographic have been em ployed.
Although the various instruments which are now in use provide the desired information theyare objectionable because they must be run into and removed from the well before the records which are made can be read. Also the photographic recording requires development and the use of photographic film with its inherent disadvantage of accidental exposureis not. desir!- able. The delay in obtaining the information instrument is run into the well, the record made, the instrument removed, and finally the record interpreted. This involves considerable time and in cases where the drill pipe is within the bore, as in a whipstock setting, there is danger of cave-in which might result in said pipe becoming stuck within said bore. The disadvantages of the present types of instruments for recording and transmitting required information to the surface have been recognized and some attempts have been made to devise methods of signalling the position of tools, or other information, to the surface by sonic means. However, these methods have not proven commercially successful because the sound is absorbed as it travels up the well bore and is not capable of detection at the surface, particularly in wells of any appreciable depth.
It is one object of the present invention to provide an improved method and apparatus for transmitting information regarding a well tool or device or regardin the well bore to the surface of the well, said information being transmitted simultaneously with the operation of the recording mechanism of said apparatus, whereby the information is made available to the operator immediately and without the necessity of removing the apparatus from the well bore; said apparatus including no photographic means whereby the inherent disadvantages of such means are eliminated.
An important object of the invention is to provide an improved method of and means for propagating electrical or radio frequency waves "A further object of the invention is to provide an improvedtransmission'system wherein electrical or radio frequency waves are generated information in accordance With said indications.
Still another object of the :invention isetomrovide an improved transmissionwsy'stem for::generating and transmitting electrical *or radio'free quency waves, which systemincludes a coupling circuit connecting the transmitter and the metallic pipe or conductor inithe;.we1l1.bore;l1said coupling circuit being tuned to the resonant frequency of the output of said transmitterwhereby the Waves are impressed upon and are guided bysaid:conductor:and'iabsorptioniof the radio frequency electrical current i energy by the} earth isprevented.
A particular object of the, invention 31s toipro; vide an: improvedapparatus .for orientings-a --lwell tool," such as a-whipstock: and havin -means for generating and ;transmitting-;radio afrequcncy waves to'the surface :of the wellebore :to signal the attainment of --a predetermineds position iby said whipstock, :wherebv-themse -.of ;-wire. -line or photographic instruments -in- -,elim=inate d; and also whereby orientation of the *well :tool is complete whenthe signal-is received'atathesurface.
Another object :of the invention is to provide an improved-apparatus, -,of ;the characters described, which is adapted :to be @mounted within the-well tool or iwhipstock-and-which includes a transmitter forgenerating.andpropagating radio frequency waves;saidtransmitter being controlled in its-operationby an-iorientingiswitch which is arranged to actuate the transmitter-whenithewell tool moves into a predeterminediondesiredjposition. ,The -apparatus also including alradio receiver which islocated :at the rwellusurfaceand which is adapteditoreceive the, signal transmitted bysaid transmitter.
.A still further-,objectlof the ,inventionlis to provide wan.improved.,apparatus, ofthe character described, wherein, thecoupling circuit, includes a variable condenser, which permits accurate tuning of said circuitto-the outputof.theitransmitter.
. The construction designed to, carryout the invention will be hereinafter described together with other features of the invention.
The inventionwill be more readily understood from a reading of the, following specification and by reference to the accompanying. drawing, wherein an exampleof the invention'is shown, an wherein:
Figure 1 is an elevation of a drill pipe having a whipstock connected to its lower end'andillustrating the transmitting instrument; constructed in accordance with the invention mounted within said whipstockandalso showing "the receiver-on the surface,
Figure 2 is an enlarged view, partly il'lfSBCtiOfl and partly in elevation, of thelower-portion of the whipstock and showing the -=mounting 'of the transmitting instrument t-herein,
Figure -3 is 'a horizontal, cross-sectional-view, taken on the liner3-=3 of-Figure '2,
Figure 4 is an enlarged, horizontal cross-ecctional view, taken ontheiline 4-44 ofiFigure 2.
Figure 7 5 is an enlarged view, --partly in section and partly in elevation and showing the outer barrel of the instrument in detail,
Figure 6 is an elevation of the lower portion of the outer barrel, 5 Figure 'Ziis amenlarged', transverse'yertical sectional viewzof' thel instrument proper.
Figure 8 is a partial elevation of the central w;. ,;portion of the instrument, said view being taken at a right angle to the parts as shownin Fig- ;--;,:Figure..9 angenlarged, horizontal cross-sectional view; taken on the line 9-4? of Figure '7, 'l ligureilodn anwenlarged, horizontal, cross-sectionalnviewptakenuon the line H2-i8 of Figure '7,
s" -'-"#Figure llisanenlarged sectional detail of the mrientingswitch,
=Figure*1'2'is'anelevation of the rotatable block ofctheiorientinsswitc V Figure 13 is a horizontal, cross-sectional view, taken-on=the line l3l3 of Figure 11,
Figure 14 is a horizontal, cross-sectional view, taken"on' therlineel'fle- [t4 'of Figure 11, @Figure115- isza-w-iring diagram -of the transmitting unit, Figure 16 is a Wiring diagram of the receiving i1 Unit,
;;Figure :17 is a wiring diagram of a modified form :of transmitting nnit,
x Figure l8 is-aview,.-similar :to Figure 6 illustratinga modified iormof coupling between the v; transmittingunitand-outer-barrel,
ti-Figure -=19 israsection'aldetail of' a compass unit arrangement which-may be substituted for the orienting-switch =.unit,
FigureiZO :is a wiring diagram of 'th'e compass c: unit shown-"insFlgure 19,
;,..-:Figur.er212is awiew partly in sectionand partly inelevation illustrating the transmitter unit applied-to an inclination indicating instrument, and, ;Eigurei22 :is an elevation ofa receiving unit whichiissemployed withthe inclination'indicating instrument .shown in Figure 21. I
4 The inventioniis:illustrated herein as applied tothe :orientation of a whipstock within a well bore but itiszpointed' out that theapparatus may beze combinedi-with well survey instruments,- well calipers; temperature and pressure indicating instruments mother-devices for transmitting-the indications of said instruments and 'devices tc 60 the-surface;
sides in the efiicient transmission of electrical orsradio frequency waves to the surface 'from within-:awell bore whereby saidwaves may be utilized-toprovide information regardingthe indicationsvof any device or instrument disposed within said-bore although theapparatus is specifically-described in connection with whipstock orientation it'isnot to'be limited'to this use.
In-athe drawlngs, the numeral H] designates a drill-pipe or :stem which is adapted to belowered Within the'wellbore A. A drill bit II is carried by :the lower end of thedrill pipe and has its tubularshank l2 threaded'onto the lower 'end of said'pipe. A'whip'stock-B of-the usual constructionisarranged to be'connected with the shank IQ of the drill-bit and said whipstock comprises an elongate wedge-shaped body l3 having a longitudinally extending inclined guide face I4 which isgenerally concave in cross-section. Due to r the -concaved guide --surface which extends =longitudinally'of the body said body is generally arcuate in cross-section throughout themajor portion thereof with thelower *end being-fully cylindrical in cross section; This extreme lower end-"of the body is sharpened or pointed as 'in- In other words, the invention re-,
5 dicated at I5 while a collar I6 is formed integral with its upper end, said collar encircling the shank I2 of the bit and being fastened thereto by a shear pin II.
The whipstock is used in the usual manner and is lowered within the well bore A by means of the drill pipe III. The lower pointed end of the whipstock is seated upon a cement or other plug C within the well bore and through a rotation of the pipe, the inclined guide face I4 of the whipstock is directed into a desired azimuthal position. After the whipstock is set, a downward force is exerted upon the drill pipe to impose the weight thereof upon the shear pin IT with the result that said pin is sheared to permit the drill pipe and drill bit to move downwardly with respect to the whipstock. The inclined face Id of the whipstock will guide the bit into the formation at an angle with respect to the axis of the well bore and if the face has been properly oriented will also guide said bit in a desired or predetermined compass direction. After drilling is complete the whipstock may be retrieved because the bit II is of a larger diameter than the whipstock collar I6 and an upward movement of the pipe and bit will result in raising the whipstock therewith. It is pointed out that the particular construction of the whipstock and its connection to the drill pipe form no part of the present invention and the foregoing description is merely explanatory to permit better understanding of the invention.
In carrying out the present invention, the rear or trailing surface of the whipstock body I3 is formed with a longitudinal recess I8 which is disposed within the lower portion of the whipstock where the body of said whipstock is larger. An indicating and transmitting instrument I is mounted within an outer barrel I9 (Figure 5) and this barrel is arranged to be attached in position within the whipstock. As will be hereinafter explained in detail the instrument is oriented within the barrel and the barrel in turn is fastened in the recess in a predetermined or known position with respect to the inclined guide face [4 of the whipstock, whereby when the instrument is mounted within the whipstock its position with relation to the whipstock face is known. The orientation of the barrel I9 within the recess is accomplished by an outwardly extending bolt which is secured in the whipstock body and which engages a diametrically extending opening 2| provided in the upper end of the barrel. The bolt not only positions the barrel and instrument in aknown position relative to the whipstock but also receives a nut 22 on its outer end to fasten the upper end of the barrel firmly within the recess I8 (Figure 3). The lower end of the barrel is secured within said recess by means of a hinged clamping strap or bar 23 (Figure 4) which overlies the outer surface of the barrel and which is fastened in clamping position by a bolt 24. With this arrangement the instrument and barrel are removably mounted within the whipstock proper and it is noted that no change other than the provision of the recess I8 need be made in the usual or ordinary whipstock now in general use.
It is noted that the instrument is mounted directly within the body of the whipstock and the indications of said instrument are made in the plane in which the whipstock is disposed. where- 1 tion to the flow of circulating fluid through said pipe. Further by mounting the instrument in the whipstock said instrument is lowered and raised with the whipstock and the use of auxiliary lines or cables for lowering and raising said instrument is entirely eliminated.
The outer barrel I9 within which the'instrument I is mounted is clearly shown in Figure 5 and comprises an elongate tubular section which has a longitudinal bore '25 of slightly larger diameter than the diameter of said instrument. An internal annular shoulder 26 is formed within the lower end of the barrel and the instrument I is adapted to seat or rest upon said shoulder. The wall of the bore 25 of the barrel is provided with a longitudinally extending keyway or groove 21 and the instrument has a radially extending key or lug 28 integral with its outer surface, said lug being engageable within the keyway to orient the instrument I within the barrel. A cap 29 closes the upper end of the barrel being secured to the barrel by a plurality of screws 30 and said cap is provided with a lug or key 3| for engagement with the keyway or groove 21 when said cap is inserted within the upper end of the barrel. The orienting opening 2I which is engaged by the orienting bolt 20 of the whipstock extends through the cap 29 and this opening is disposed in the same vertical plane as the keys 3I and 28 as well as in the same plane as the longitudinal keyway or groove 21. Thus, it becomes apparent that the'instrument I is mounted within the barrel I9 in a known position with respect to the orienting opening 2| of the barrel and when said opening bears a known relationship to the whipstock face I I as it does when said barrel is in position within the recess I8 of the whipstock, the instrument I is in a known or predetermined position with respect to said whipstock face.
The lower end of the tubular barrel is externally screw-threaded and. is formed with a reduced counterbore 32 which extends downwardly from the internal shoulder 25. The lower portion of the counterbore is provided with an annular seat 34 which is arranged to be engaged by the upper conical head 35 of a cylindrical supporting member or rod 35. The member 36 is constructed of an electrical insulating material and is held in position against the seat 34 by a bull plug or closure 36A, the latter having an internal shoulder 37A which engages an external shoulder on the member for forcing the conical head 35 against the seat when the plug is screwed onto the barrel. The member or rod forms a support for a coupling circuit which electrically connects the instrument I with the exterior surface of the barrel I9 and as is clearly shown in Figure 5 a conductor 31 extends from the instrument and downwardly through the member; this conductor is then directed upwardlyalong the exterior of the member and is connected to the exterior of the plug at 38 to make electrical connection therewith. A variable condenser 39 is connected in the conductor and permits tuning of the coupling circuit formed by said conductor as will be hereinafter more fully explained. It is preferable that the conical head 35 of the member 36 be constructed of a resilient or elastic material whereby when said head is forced against the seat.3l said head is moved into tight engagement with the conductor to seal off around said con ductor and thereby prevent fluids which might s ear-94 ber 38 is subject to variation and-the exterior thereof is preferablyspaced'from the walls ofthe recess 18 of the whipstock when the 'barrel is mounted withinsaid recess (Figure l) whereby the conductor 1-? is not in direct engagement with the metallic whipsto'ck, V v
It is pointed out that the coupling circuit which is illustrated and described herein may be varied in' physical structure without departing from the invention. r I
As will be explained, the instrument within the "barrel is is adapted to generate electrical radio waves to indicate the attainment of apredetermined position by the whipstock and said waves are transmitted over the conductor?! and are propagated along'the barrel l9. Since this barrel is metalilc and directly engages the whipstool: said waves are guided upwardly along the whipstcck and then upwardly along the drillfpipe id to the'surface. Thus the drill pipe becomes the guiding medium for'said waves whereby the arrival of such waves atthe surface is assured. The reception of the transmitted radio 'wavesat the surface isaccomplished by a common superregenerative receiver 4 6. This receiver includesa receiving antenna 4! and head phones 42 and will be described more in detail in connection with the wiring diagram thereof shown in Figure 16. The use of head phones is not essential and any other means of indicating the reception of the transmitted radio frequency waves may be employed. Upon receiving the transmitted waves at the surface the operator is advised that the 'to the drill pipe to perform the'drillingioperation.
The arrangement provides an instantaneous indication and the instrument need not be removed before drilling canbe continued; the instrument remains attached to the whipstock until the drilling' operation is complete and issubsequently removed from the well bore when the whipstock is recovered upon lifting of the drill pipe.
The instrument I which is mounted within the barrel id illustrated in detail in Figure 7 to 14. Itmight be pointed out that the particular construction of this instrument is subject to variationso far as specific structural features are concerned. and therefore several-modifications of the basic principle of the instrument are possible without departing from the spirit of the invention.
i, our separate sections 52, .53 and 54. The uppermost section is a tubular battery section and houses a B battery 55 and an A battery As illustrated, the instrument includes an outer casing or housing which is constructed said batteries being separated by an insulated partition Acap 5'l.closes the upper end of the battery section and a coil spring 58 which is to the section 52 therebelow by acoupling 59. A suitable spring so isinterposed between the cou-' pling and the lower end of the battery 55A and holds saidbattery in positionwithin its section.
explained. A window or opening .62 is formed in thesection52 to permit access to the timing mechanism for setting and .viewing said mechamsm. V
The lower end of the section 52 is threaded onto the upper [end of the next section 53 of... the instrument, this latter section comprising ,an orienting switch unit. The unit is clearly .illustrated in. Figures 10 to 14 and as shown, the. section 52. hasa bore 53 which has its upper. end'closed by an integral topplate 6.4. An orient-- ing block 65 is rotatably mounted withinuthe bore 63 a-ndis constructed of electrical insulating The, upper marginal edge portion of material. said block is bevelled at 66 and this bevelled portion abuts an internal inclined shoulder 61 formed within thev upper end of the bore 63 ofthe section '52, the block being held in position within said section by a retaining ring .68 which is threaded into the lower end of the section. An annular groove or recess 69 is provided within the block and is adapted to receive a metallic ball It which is responsive to gravity as the in strument is inclined. The ball is arranged to close an electrical circuit between an arcuate' contact H which is embedded in one verticalwallof the .recess .69 and a second contact 12 which.
is embedded inthe bottom of said recess; unless the ball is engaging both contacts the electrical circuit between said contacts 'is open. The contact H is connected through a wire 13 with a contact ring I lsecured to the upper surface of the block. The top 5% of the block has an annular recess 15 within which the contactring.
is disposed and a contact brush i6 is also mounted within this recess and. constantly engagesthe.
contact ring. A-lead wire T! is connected to the brush and extends upwardly through the instrument to one side of the B battery 55.
The lower contact 12 of the orienting switch unit haselectrical connection with a lower.-con-. tact ring 18 secured to the underside of the block 65 and a contact brush l9 rides upon this ring.
The contact brush is secured to the wall of he' lowermost section. 54 of the instrument. and a wire connects said brush with the transmitter mechanism housed within the lowermost section.
It" is apparent that because of the brush and contact ,ringeonnections, the block may be rotated to various positions within the section 53 without interrupting the electrical connection.
The section 53 within which the orienting switch unit is mounted has the orienting key or lug 28 secured thereto and as previously explained, it is this key or lug which orientsthe instrument I within the barrel l9 and thereby orients said instrument with respect to the whipstock face. Since theangular position of the key 28 with relation to the whipstock face 3 is known, it
is only necessary to know the position of the 'con tacts ,H and with respect to said key in order tolascertain the relative angular positions of the whlpstock face and said contacts.
The timing mechanism is,
v In order to I adjust'these -contacts accurately with respect'to the key 28, the section 53 is provided with an arrow or marker BI (Figure 8) above said key. An opening or window 82 is cut in the section 53 so that a portion of the exterior of the block 65 is visible therethrough. The exterior of the block has an indicating dial 83 thereon and this dial is marked ch in degrees. The indication on the dial is radially aligned with the contacts II and '12 (Figure and thereby indicates the position of said contacts within the block, The dial reads from 0 to 180 to the right and left of the 0 (Figure 12) and thus byadjusting the block to locate said dial in a desired position with reference to the indication BI and key 28 the exact angular relationship between the contacts and the key 28 is indicated. To facilitate rotation of the block 65, the upper portion may be knurled as shown at 84 and a portion of this knurling is exposed through the window to permit manual manipulation of the block. A set screw 35 (Figure 11) is threaded through the wall of the section 52 and engages the exterior of the block to frictionally hold the same in its adjusted position.
Prior to lowering of the instrument I, the orienting switch block is adjusted with respect to the key and for the purposes of this description it will be assumed that the 0 indication is aligned with the marker 8i and key 28. Thus when the instrument is inserted within the bar rel, the contacts H and I2 are aligned with the key way and upon attachment of the barrel to the whipstock said contacts are 180 degrees opposite the whipstock face. Since the ball 10 will always seek the low side of the well bore, it is obvious that said ball can engage the contacts II and I2 only when said contacts are at the low side of the well bore. Therefore, since the direction of inclination of the well bore is known, the compass direction of the low side of said bore is known with the result that the closing of the circuit between contacts II and I2 by the ball 70 is indicative of the compass position of said contacts. Assuming that the whipstock face is 180 degrees opposite the contacts, then it follows that the closing of the circuit between said contacts indicates the azimuthal or compass position of the whipstock face.
The engagement of the contacts H and I2 by the gravity responsive ball I0 closes an electrical circuit to a radio frequency wave transmitter T which is mounted within the lowermost section 55 of the instrument. This transmitter is connected to the conductor 3! of the coupling circuit and when actuated ropagates radio frequency waves which are guided along the whipstock and drill pipe I0 to the surface of the well. These waves, as has been stated, are received by the receiver 40 at the surface of the well, such reception indicating that the ball I0 has engaged the contacts I! and i2 and that said contacts are adjacent the low side of the well bore. Since the angular relationship between the contacts and the whipstock face I4 is known, the reception of the radio waves b the receiver 40 indicates the exact compass position of said whipstockface.
The transmitter T may within certain limits be varied in design and a suitable arrangement is illustrated in Figure wherein a complete wiring diagram of the instrument is shown. The B battery 55 has its positive pole connected through the wire II with the orienting switch unit which includes the gravity responsive ball I0 and contacts H and I2. The negative side of the battery is grounded. The positive side of the A battery 55A is connected by wire 06 with the timing mechanism BI and the switch of said mechanism controls flow through said mechanism. The negative side of said A battery is also grounded. The orienting switch unit has connection throughrthe conductor with the transmittenwhile the timing mechanism also has connection with said transmitter through a wire 88. Thus it is apparent that both the switch of the timing mechanism GI and the orienting switch formed by the ball I0 and contacts II and I2 must be closed before the transmitter T can be operated. If one or the other of these switches is not closed, operation of the transmitter is impossible. The timing switch is arranged to close in accordance'with a predetermined setting of the timing mechanism while the orienting switch closes when the contacts II and I2 are disposed adjacent the low side of the well bore and are engaged by the ball. In actual operation, the timing mechanism is set in accordance with the time required to lower the whipstock in position and the switch closes automatically after such predetermined lapse of time. The drill pipe'is then rotated to rotate the whipstock and instrument I which is attached thereto; the ball seeking the low side of the well bore will remain substantially stationary and as soon as the contacts 'II and I2 move into alignment with the ball the transmitter is actuated.
The transmitter includes an audio oscillator tube which comprises a filament or cathode 9|, a. control grid 92, screen grid 93, suppressor grid 94 and a plate 95. The filament 9| has the wire 88 extending from the timing mechanism and A battery connected thereto, whereby as soon as the timing switch closes, said filamentis heated. The A battery is also utilized to heat the filaments or cathodes 96 of a modulated radio frequency oscillator tube 97, the electrical con nection being made through a conductor a which extends from the wire 88 to said filaments.
This latter tube includes grids 98 and plates 99. A transformer I00 has its primary winding i00a connected through wire IOI with the wire 80 extending from the orienting switch unit whereby a current flow occurs when the orienting switch is closed. The primary is connected b wire .I02 with the plate 9 5 of the audio oscillator tube 90.
The secondary I002; of the transformer has con-- nection through wire I03 with the control grid 92 of the audio oscillator tube and a bias resistor I04 is connected in the transformer secondary circuit. The secondary I00b of said transformer is also electrically connected with the grids 98 of the radio frequency oscillator tube '97 by leads I05 and I06. Suitable R. F. chokes I0'I are interposed in these leads. Conductors I08 and I09 extend from the leads I05 and I06 respectively and have connection with a tank coil or winding IIO. This coil is energized through a conductor II 0a which extends. from the wire 86 leading from the orienting switch unit and B battery and an R. F. choke IIOb is interposed in this conductor. Condensers WM and I09a are connected to grids -98 through wires I08 and I09, and feed back energy to the tube 91 in such manner as to sustain oscillation in the usual manner. The coil I I0 has its terminals connected by wires III and H2 with the plates 99 of the R. F. tube 91, and a-variable condenser MM is connected between the wire III and H2, whereby the tube oscillates at the resonant tuned frequency of the erra a coil H9 and condenser 2a, The usual, by pass condensers ll3fare associated with the fila-f ments and grids of the tube 91,
' With the particular arrangement above described, the timing switch 6| is first closed to direct current to the filament or cathode 9| of the audiotube 99 and also to the filaments or cathodes 96 of the R. F. tube 91. Atsuch timethe transmitter is inactive so far as radio frequency wave transmission is concerned and it is only when the orienting switch formed by ball 10 and contacts H and 12 is .closedthat radio waves are generated. Upon closingv of the orienting switch, a current flow from the B? battery to the primary, 10011 of the transformer I and thence to the plate 95 of the audio tube. 90,, occurs; simultaneously the coil H0 and plates 99 of theft. F.
tube 9'l'are energizedthrough the wire 80 and conductor Ilfla. The"primary [9911" of the transformer induces a voltage'in the secondary IUUb and this induced voltage affects the control grid 92 of the tube 90 and atv thesame time affects the grids 98 of the R. F. tube. Actually,
the transformer is a tuned circuit for controlling the audio tube oscillation and for modulating the grids of the B..- F. oscillator tube 91, The voltage applied to the transformer primary varies in accordance with the oscillations of. the audio tube,
and therefore the voltage applied to the secondary I091; of said transformerincreases and decreases the total bias voltage, thus varying the output of the R. F. oscillator tube at thejrate at which the voltage is variedacrose the secondary of said,
From the foregoing itwill be seen that when the orienting switch is closed the transmitter is set into operation and the'R. F. tube oscillates at the resonant tuned IIYGQUeIICX OfItI'lBCOiI H0- ceived by the receiving unit 40.
It is pointed out that the coupling circuit formed by the conductor 31 which connects the' transmitter T to the metallic barrel I9- and drill pipe 19 is an importantfeature of the invention. This conductoris of sufficient length to provide-a circuit which is tuned: to the resonant frequencyof the transmitter output: The variable con-' denser 39 which is connected in the conductor is by making the. apparatus, practical in wells .of anydepth.
The receiving unit 40 is a common superregenerative receiver and is shown in the wiringdiagram of Figure 16. The receiver includes a radio frequency oscillator tube H5 which has its, plate circuit coupled to the primary of a trans-. former I Hi and audio current variations across the transformer induce a voltage in the secondary of said transformer, which voltage is amplified by, tube I Ilia andconducted to the head phones 42. The tube H5 oscillates at the frequency of the received signal at an interrupted rate which is ordinarily above the audio range. When the signal is received by the antenna 4|, it is applied to..- the grid of the .tube and affects the amplitude of 'the oscillator. The variation of the trans-.- mitter results in a corresponding variation in thepower output of the tube I l5. Thus, the received signal is audible through the head phones 42. to
-' indicate that the whipstock face has reached a predetermined compass position.
The transmitter which has been described and which is illustrated in Figure 15 is a grid modulated transmitter and a modified form which is plate modulated is illustrated in Figure 17. In this arrangement, the tubes 99 and 97 as well asthe transformer l 09 are employed. However, instead of the secondary of the transformer being connected to the grids 98 of the tube 91, said sec-. ondary is directly connected with the B battery.
merely for the purpose ofproperlytuning the circuit without the necessity of extending-the length of conductor; in other, words, when" the-condenser 39 is usedthe conductor maybe shortened where-. as omission of said condenser. would require a longer conductor 31, In both instances, however,
the requirement for eiiicient operation isthat the the mechanism since said waves will be guidedby said pipe throughout, itsentire length,,;th ere 7 supply and then to the plate circuit of the tube 91. In this instance the transmitter is plate modulated but will function to transmit radiofrequency. waves in the same manner as the transmitter T hereinbefore described.
It is evident that various transmitter hook-ups couldbe employed and for this reason, the invention is not to be limited to the particular structures illustrated.
When the apparatus is to be used, a preliminary survey of the well bore is first made by any of V the well known survey instruments to determine the direction in which the well bore inclines at the elevation at which the whipstock B is to be set. -For purposes of this description, it will be assumed that the bore A is inclining nort adjacent the plug C in said bore and also that it is desired to drill in the north direction; this means that the whipstock face I4 must be oriented so that said face is directed north. With the bore inclining toward north it is obvious that the low side of the well bore will be de-. gress opposite north, or south. It might be noted that in most instances, previous well surveys have made this information available so that said survey just prior to use of the present apparatus may not be necessary. 7
The timing mechanism ii of the instrument I; is first set so that sufficient time may elapse to allow lowering of the whipstock before the switch is closed. The orienting block 65 is adjusted with respect to the key 28-0n the instrument housing or casing so'as to dispose the contacts H and 12 in the desired angular relation thereto. Because. the key 28 is always 180 degrees opposite the whipstock face, due to the mounting of the barrel l9 in a predetermined position, the angular relationship between the contacts H and i2 and whipstock face must be adjusted in accordance with the direction in which drilling is to proceed.- It is known that the circuit between the contacts H and 72 will be closed by the gravityresponsive ball Hi when said contacts move adjacent the low side of the well bore, which as as-, sumed herein is south direction. Drilling isto:
proceed in a nort direction so -in the-assumed instance, the contacts i I and 12 must be 180 de-' grees opposite the whipstock face; the block 65 is therefore adjusted to locate the 0 indication (which indicates the location of the contacts) in alignment with the marker 8|. Of course if the whipstock face I4 was to be directed due east or due west, the block would be rotated in one direction or the other 90 degrees from south to locate one of the 90 indications on the dial in alignment with the marker 82 and key 28. It is obvious that any desired adjustment of the block to vary the angular relationship between the contacts II and i2 and the whipstock face I4 is possible.
After the timing mechanism and orienting switch unit are adjusted, .the instrument I is inserted within the barrel I9 and said barrel is mounted and attached within the recess I8 of the whipstock. The instrument is oriented inthe barrel by the key 28 and groove 2T while the barrel is oriented with respect to the whipstock face by the orienting opening 2| and bolt 29. Thus when the instrument is mounted in the whipstock, the contacts TI and I2 bear a known fixed angular relationship to the whipstock face I4. The whipstock is then lowered through the well bore A to the elevation at which it is to be set. The timing mechanism is so adjusted that the timing switch 6! is closed at approximately the time the whipstock has reached the desired position so that current from the A battery is flowing to the filaments of the tubes 90 and 91.
As the whipstock reaches position and its lowering is halted, the gravity responsive ball 10 seeks. the low side of the well bore and since such low side has been presumed to be in a south direction the ball will roll to such position within,
the annular groove 69 of the orienting block and will remain there. If by coincidence the contacts II and I2 are also disposed in a south direction the ball engages the contacts to close the circuit therebetween and actuate the transmitter. However, in almost every instance the contacts II and 12 will be misaligned with the ball resting in a position adjacent the low side of the well bore and a rotation must then be impartedto the drill pipe IIl.
As the pipe rotates, a rotation is imparted to the whipstock and to the instrument mounted therein whereby the contacts I I and I2 are moved circumferentially within the bore A. As the contacts move adjacent the low side of the well bore or in a south direction, said contacts are enof the radio frequency electrical current energy by the surrounding earth and the waves attach to and are guided by the metallic drill ,pipefto the surface. The radio signal transmitted by the transmitter unit T is received at the surface by 7 the receiver 4!! and as soon as said signal is received, it is known that the whipstock face I4 is facing in the desired compass direction. -Obviously, in the assumed case the signal is transmitted when the contacts II and 12 are located adjacent the low side of the bore, which is south and since by prior adjustment said contacts were disposed degrees opposite the whipstock face I4, said face is directed north when the signal is transmitted. Upon reception of the signal, the pin I'I connecting the drill pipe and whipstock may be sheared and the drilling operation immediately begun. The timing mechanism may be constructed so as to again open the switch 6| after a sufiicient time to obtain orientation of the whipstock has elapsed whereby the transmitter unit is automatically shut off after orientation is complete.
The'device as hereinbefore described for whipstock orientation includes the orienting switch unit which depends upon the gravity responsive ball 10 whereby the position of the whipstock face is determined by correlation with the low side of the well bore. In this apparatus it is necessary that a preliminary survey of the well tuted for the orienting switch arrangement shown in Figure 11. The compass unit includes a tubular section I28 which is arranged to be substituted for the section 53 of the instrument I. The section IZil has a bore IZI which has its upper end closed by an integral top I22 with its lower end closed by a, plate I23, the space between the top and the plate forming a compass chamber I24. A compass I25 is mounted on a compass pin I25 and said compass is formed with an opening I21 which is indicative of a compass direction which in this case will be presumed to be north. Thus, the opening i2? is always in a position directed toward north. Transparent plates I28 are mounted within the chamber IM and provide a chamber in which a dampening fluid for the compass may be contained. A lamp I29 is mounted in the top I22 of the section and is in vertical alignment with a photo-electric cell I30 secured to the bottom plate [23. The lamp and photo-electric cell are in radial alignment with an orienting key 28a similar to the key 28 on the section 52, whereby said lamp and cell are located in a predetermined known angular, relationship to the whipstock face.
lamp and photo-electric cell, the light rays from the lamp are directed onto the cell I33. Reception of the light rays will actuate a relay I3I which closes a relay switch 132. The relay switch I32 is comparable to the orienting switch formed by the ball in and contacts fl and I2 whereby the transmitter T is actuated whenever the compass opening I2! is in alignment with the photo-electric cell.
In this structure the whipstock and instrument will be constructed of a non-magnetic material 1 :30 that the free operation of the compass I25 is not afiected. The apparatus is lowered in the well bore and the angular relationship of the photo-electric cell I3!) to the whipstock face is known.
the opening I21 directed toward north. The
drill pipe and whipstock will then be rotated to impart a rotation to the instrument so that the photo-electric cell I30 is moved circumferentially within the well bore and beneath the compass which is, of course, held stationary. The lamp It is evident that when the opening I21 is aligned with the The compass will, of course, maintain m is illuminated by the timing switch a'ridwheir the photd-el'ectriccell moves beneath-the opening" I27. saidcell receives light rays to actuate or close the relay switch I22. At such time the transmitter-is actuated to send a radio frequency. The reception of this sig-. nal will indicate that the photo-electric cellis in the north direction and since the operator signal to the surface.
knows the angular-relationship between said cell and the whipstock face the direction of said face is known. This particular arrangement: Whichincludes a compass might be termed a direct method as compared to the indirect method which utilizes the low side of the ;well bore as the point from which the position of the whipstock face.
Although .the invention is particularly useful in the orientation of whipstocks or other deflecting tools, the principles of said invention may be appliedto other types ofwell survey instruments and in Figure 21 the invention is shown as employed with a drift indicator or inclination instrument I 33. The instrument includes the transmitter T and control of the audio oscillator frequency is effected by means of a plumb bob I 34 which is movable over a carbon plate I35. The plumb bob forms a contact arm and obviously as it moves over theplate to various positions.
due to difierent degrees of inclination, the resistance in the circuit to the frequency of the audio oscillator is changedwhereby the trans-'- accordance with the position of the plumblbob.
A receiving unit I36 is located at the surface and includes a frequency meter I37. The'radio frequency signal is received by the unit I and demodulated and the audio component is conducted to the frequency meter for the frequency determination. The dial I38 of the frequency meter may be computed in degrees whereby the various frequencies are representative of different degrees of inclination of the well bore.
the surface along said conductor; in this .ar-
rangement the cable or wire line functions as the} guide medium in place of the drill pipe when the apparatus is used in whipstock of deflectingi tool orientation.
The foregoing description of the invention is explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made,-
within the scope of the appended claims, without departing from the spirit of the invention.
What we claim and desire to secure by Letters;
Patent is: I
1. An apparatus for transmitting. intelligence to the surface from within a well bore including a metallic conductor, an indicating mechanism having a metallic housing connected :to the The instrument I33 may be lowered on a metallic cable orWire line and the propagated radio waves are guided to mitter is modulated at different frequencies in,
metallic conductor extending through the well bore, a transmitter within the lower portion of the housing for transmitting radio frequencywaves, means for electrically connecting the indicating mechanism with the transmitter whereby;
the radio waves generated by the transmitter are representative of the indication of the indieating mechanism, and means for electrically connecting the transmitter to the metallic con-- ductor by a coupling circuit to reduce earth absorption losses, said circuit including a longi-: tudinal supporting member of electrical insulatw ing material secured to the lower portion of the" housing and projecting longitudinally therefrom, I
ant-s mmer conductor extending longitudinally through the center offsaid supporting member and having-one end" electrically connected to the transmitter with itsoppositeend extendin out-- wardly from the support'and'then extending par allel to the exterior-thereof, the outer extremity'of' said conductor beingelectricallyconnected to" the exteriorof the metalli'o housingwithin which the transmitt'er 'is mounted. a
2: An apparatus as set forth in claim 1, to-
geth'er-witlt a radio wave receiver at the surfaceforreceivln'g'the'transmitted waves.
3." An apparatusasset forth in-claim 1, wherein the coupling'circuitds tuned to. the resonant frequency of the transmitter output.
4am; apparatus adapted to be lowered 'into'sa wellbore -forsignallin to the surface the attain ment' of a= predetermined "compass position of an element within: said well bore 1 including, 4 a metallic ,conductor extending through said bore; an electrical switch; unit including a metallic-- housing attachedto. said conductor and having; fixedycircuit; closing contacts which are normally in electrical di sengagement and which are mov:
able .circumferentially.within said bore when the conductor isirotated, said switch unit also having agravity responsive movable contact member adapted to engage thefixed contacts to close the vGcircu'it therebetween when saidcontactsmove into alignment with said gravity respon-.
sive contactmember, whereby said circuit is closedlwhen the fixed .contacts assume a predetermined known compass position, a radio frequency..transniittermounted' within the metallic housingelectrically' connected to said switch unit and actuatedjwhen'the contactsv of said switchjare'in" circuit" closing position to trans-.
mitra'didwavesof a fixed frequency, whereby said transmitter is operated only when the fixed contactsof theswitchunit are ina known'preing a longitudinal supporting member of electricalinsulating material a secured to the lower portion-of the;metal1ic housing. an electrlcali'. conductorgextending longitudinally through thei support and having; oneendelectrically connected tqthe transmitterewith its opposite end extend--- ing-..outwardly-along-the exterior surface of the-- member and with the extremity thereof electri-- cally connected lto the: metallic housing within which the transmitter is mounted.
5L An apparatus as set forth in claim 4, together with'ai radio wave receiving unit at the surface of the well 'bore'andspaced'from the'metallic conductor forfjr'eceiving the transmitted waves and'transposingtlie' same into an audible signal.
6. An'apparatus "as set forth in claim 4, together'with'a timing" mechanism having an electrical"circuit=closing means connected in the transmittercircuit; whereby said. transmitter cannoti'operateuntil-the-"timing mechanism circui't-closir'rg means is actuated, and'means for adjusting thefoperation ofthe timing mechanism tocontrol thetim'e of actuation of the transmitter.
73 An apparatus asset forth in claim 4, wherein the 'means for couplingthe transmitter to the conductor is'tune'dto thefreq'uency'of the out-* put 0? said transmitter-.
8. An apparatus adapted to be lowered into a well bore for generating and transmitting a signal to the surface including, a rotatable metallic conductor extending through said bore, an electrical switch unit having a metallic housing attached to said conductor and having circuit closing means for closing an electrical circuit when the unit is moved into a predetermined known compass position by rotating the metallic conductor, a radio frequency transmitter mounted within the housing and electrically connected to said switch unit and actuated when the switch is in circuit closing position to transmit radio waves of a fixed frequency, whereby the transmitter is operated only when the switch unit is in a predetermined compass position, and means for coupling the transmitter to the metallic conductor to impress the radio frequency waves on said conductor so that said waves are guided by the conductor and are transmitted to the surface by said conductor, said coupling means reducing absorption of the radio frequency electrical energy by the surrounding earth. and comprising a longitudinal supporting member of electrical insulating material secured to the lower portion of the metallic housing, an electrical conductor extending longitudinally through the support and having one end electrically connected to the transmitter with its opposite end extending outwardly along the exterior surface of the member and with the extremity thereof electrically connected to the metallic housing within which the transmitter is mounted.
9. An apparatus as set forth in claim 8, wherein the means for coupling the transmitter to the conductor is turned to the frequency of the output of said transmitter.
10. An apparatus as set forth in claim 8, together with a timing mechanism having an electrical circuit-closing means connected in the transmitter circuit, whereby said transmitter cannot operate until the timing mechanism circuit-closing means is actuated, means for ad-- justing the operation of the timing mechanism to control the time of actuation of the transmitter, and a radio wave receiving unit at the surface of the well bore and spaced from the metallic conductor for receiving the transmitted 18 waves and transposing the same into an audible signal.
11. As a sub-combination in a transmitting apparatus having a housing, a coupling circuit including, a longitudinal supporting member of electrical insulating material fastened to one end of the housing and projecting longitudinally therefrom, an electrical conductor extending longitudinally through the center of said supporting member and having one end electrically connected to the transmitter within the transmitter housing, the opposite end of said conductor extending outwardly from the support and then extending parallel to the exterior thereof, with its extremity electrically connected to the exterior of the transmitter housing.
RALPH W. GOBLE. GORDON JACKSON.
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|U.S. Classification||175/45, 340/855.2, 333/236, 33/312, 340/854.6, 455/128, 333/33, 340/870.16, 175/41|
|International Classification||E21B47/02, E21B7/04, E21B7/06, E21B47/12|
|Cooperative Classification||E21B47/122, E21B7/061, E21B47/02|
|European Classification||E21B7/06B, E21B47/12M, E21B47/02|