|Publication number||US2589534 A|
|Publication date||Mar 18, 1952|
|Filing date||Jul 28, 1947|
|Priority date||Jul 28, 1947|
|Publication number||US 2589534 A, US 2589534A, US-A-2589534, US2589534 A, US2589534A|
|Inventors||Buttolph Ralph Q|
|Original Assignee||Buttolph Ralph Q|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (10), Referenced by (41), Classifications (8)|
|External Links: USPTO, USPTO Assignment, Espacenet|
March 1952 R. BUTTOLBPH DRILL GUIDING ASSEMBLY Filed July 28, 1947 2 SHEETS-SHEET l nrroe/v y March 18, 1952 R. Q. BUTTOLPH DRILL GUIDING ASSEMBLY 2 SHEETS-SHEET 2 Filed July 28, 1947 Patented Mar. 18, 1952 UNITED STATES PATENT OFFICE 2,589,534 DRILL GUIDING ASSEMBLY Ralph Q. Butto'lph, Long Beach, Calif. Application July 28, 1947, Serial N9. 764,069
This invention relates to a drill guiding assembly and it is a general object of the invention to provide a simple, practical, effective drill guide and structure including one or more such guides all particularly useful in directional or slant drilling operations.
When wells are drilled by the rotary method there is a tendency for the bore to deflect from the desired course. Drill collars are used in the course of ordinary drilling as stabilizers to keep a drill straight and it has been proposed to use bit guides adjacent or in the vicinity of the bit to keep the bit headed straight. When a bore has been deflected, as by a whipstock, it hasbeen difficult or impractical to use a drill collar of effective size, and so far as I am aware no satis-- factory control has heretofore been provided to maintain a bit headed in the desired direction.
A general object of my invention is to provide a drilling assembly which will effectively control the directional action of a drilling bit to cut the desired well bore.
An object of my invention is to provide a means whereby the bit may be guided to cut -a straight perpendicular well bore, or may be guided-to cut a straight deflected well bore without lateral off course deflections, or may be guided in a defiected bore to increase or to decrease the angle of deflection of the bore without lateral off course deflections of the bore.
An object of my present invention is to provide a drilling assembly involving, in combination, a 7
bit, a drill collar, and a guide or stabilizer .at the upper end of the drill collar. With my arrangement the guide being located at the upper end of the drill collar allows the drill collar to depend in the well and guide the bit in a-most advantageous manner.
Another object of the present invention is to provide a structure of the general character referred to in which there are two guides, one at each end of the drill collar, which guides serve to effectively prevent pitching or tilting of the collar in the bore. By providing guides which substantially fit the well 'bore and by locating such guides at the ends of the drill collar, the drill collar is positioned in the here to be substantially parallel therewith so that-the bit operated by the collar feeds straight ahead Without deflection.
It is another object of the present invention to provide a structure of the general character referred to in which there is a guide at the'lower end of the drill collar which guide serves to effectively control the deflection of the well bore to increase it or to decrease it as circumstances require. a
It is another object of the present invention to provide a guide construction applicable to a drill collar, or the like, to serve as a coupling between the drill collar and a bit of a drilling string.
Another object of the invention is to provide an improved practical guide construction involving few simple dependable parts. The structure that I have provided is simple and rugged so that there is no danger of it becoming fouled or its parts becoming detached in the course of operation. The guide involves cutting blades at each end which may normally operate with or without cutting or removing formation from the wall of the well bore to protect the guide so that it can be dislodged should there be a tendency for the guide to become stuck in the bore.
Another object of the present invention is to provide a guide of the general character referred to including adequate bearing surfaces to bear against the wall of the well bore and adequate support for the element on which the bearing surfaces are located.
It is a further object of the invention to provide a guide of the general character referred to involving a guide element rotatable on a body and confined between collars spaced longitudinally on the body which collars are provided with projecting blades serving to out well formation when it is necessary to provide clearance for passage of the structure. It is also an object of the present invention to provide a guide structure of the character referred to which may be readily released should it tend to become stuck or lodged in the well bore. The structure that I have provided may be operated to jar it loose for easy removal from the well bore.
The various objects and features of my invention will be fully understood from the following detailed description of typical preferred forms and applications of the invention, throughout which description reference is made to the accompanying drawings, in which:
Fig. 1 is a somewhat diagrammatic view showing a well bore with a guide embodying the construction of the present invention located at the lower end of the drill collar or between the drill collar and bit and illustrating the manner in which the drill collar tends to become tilted or bowed in the well bore when the bore is deflected or slanted to increase the deflection of the bore. Fig. 2 is a view similar to Fig. 1 illustrating a construction or arrangement provided by the present invention wherein two guides embodying the invention are employed in connection with a drill collar, one at each end of the drill collar so that the drill collar-is supported centrally in the bore and -co-axia-lly therewith regardless of the pitch of the bore. Fig, 3 is a view similar to Figs. 1 and 2 showing an arrangement wherein one guide embodying the constructionof the present inventionis provided at the upper end of the drill collar, the-structure being located in a substantially vertical gbore so that the guide serves to stabilize the drill collar holding it centrally in the bore. Fig. 4 is an enlarged side elevation of a guide embodying the present inventionshowing it joined to well parts such as abit and drill collar. Fig. '5' lS a longitudinal sectional view of the structure shown in 'liig. 4 illustrating the details of construction. Fig. 6 is a detailed transverse sectional view taken as indicated by line 6-6 on Fig. 5. Fig. '7 is an enlarged detailed similar to Fig. 6 showing a modification of the guide of the present invention, and Fig. 10 is a 4 and it can be controlled to increase the'inclination of the well bore at the desired rate.
In Fig. 3 of the drawings I show an arrangement where but one guide B provided by my invention may be employed in combination with a drill collar A, in which case the guide B is at-- tached to the upper end of the drill collar being employed as a connection between the lower end sectional view taken as indicated by line Iii-l9 on Fig. 9.
-The structure of the present invention involves, primarily, an assembly which includes a drill collar.A and guide means therefor preferably an upper guide B and a lower guide C. In the preferred application provided by my invention the guides are joined to. or arranged. at the ends of the 'drill collar so that the upper guide occurs between the upper end of the drill collar A and the lower end of the usual drilling string D while the lower guide C'oc'curs between the lower end of the drill collar A and the drilling bit E.
'More specifically,'my invention provides a guide construction anda guide embodying my invention may be used in any suitable manner. In Figs. 1, 2 and 3 I show three typical applications of the guide construction that I have provided.
In Figure 1 I show the 'guide construction applied to the lower end of the drill collar only and the structure operating in a deflected or slanted bore, in' which case the operating condition is such that the bit E is deflected or pitched further in the direction in which the bore is inclined. The guide C which does not rotate forms a bearing point-and fulcrum about which the assembly of; drill collar, bit and guidepivots or tilts, allowing the upper end portion of the drill collar to bear against the lower side of the well bore, as indicated at X in Fig. 1. The drill collar being heavy and substantially rigid maintains itself substantially straight between guide C and bearing X. With the guide C made to fit or to substantially occupy the bore the degree of deflection of the bit is governed by the length of the drill collar. Ordinarily slight deflection is desired in which case I may use a drill collar of considerable length. For example, I may use a drill collar as much as eighty feet in length and gain slight deflection of the bit.
The flexibility of the long collar allows it to belly or bow somewhat toward the lower side of the well bore or in the direction indicated by the arrow Z in Fig. 1. The weight applied by the drilling string to the upper end of the drill collar further assists in bowing the collar as it applies the'necessary pressure to the bit E. It will be seen from the drawings that the lower end of the drill collar supported by the guide C is at a slight angle to the axis of the well bore. The guide acts as a fulcrum and the bit E coupled to the collar A by the guide C is carried at a slight but effective angle to the well bore to out or feed somewhat into the upper side thereof as indicated by arrow Y. It will be obvious that as the well is bored the bit E will out into the upper side thereof which action will continuously increase the angle or deflection of the well bore. The amount of deflection per unit length of well bore may be controlled by the length and flexibility of the collar A and through the relationship of the bit E to the fulcrum created by the guide C. By providing a drill collar of substantial length the amount of lateral deflection is minimized. By, providing a guide of the character herein disclosed, which guide has no cutting action, the action above described isrendered highly eifective of the drilling string D and the upper end of the drill collar. When such a construction or arrangement is provided it can be used to advantage in a substantially vertical well bore, as shown. in Fig. 4, since the drill collar Awill depend vertically from the guide B and thus carry the bit so that it drills straight down into the formation.
In Fig. 2 of the drawings I illustrated an arrangement provided by my invention, in which case the drill collar A, which may be of typical or standard construction is equipped at each end with a guide, at the lower end with a guide C and at the upper end with a guide B. The guides C and B are of such size as to substantially conform to the bore so that they form effective bearing means in the bore and when so engaged in the bore they support the drill collar A centrally of the bore so that the bit E advances in the direction in which the bore is pitched and does not lead or feed off or deflect.
The guides C and B provided by the present invention are preferably alike or of identical construction and therefore, I will describe but one of the guides, it being understood that the description is applicable to both. The guide construction that I have provided and which is fully illustrated on sheet 2 of the drawings involves, generally, an elongate body 10, upper and lower collars I! and I2 on the body mounted in fixed position thereon, a bearing sleeve l3 on the body between the collars, and a rest I4 carried on the sleeve l3 between the collars.
The body It] is preferably a simple elongate tubular part having threaded portions 16 at its upper and lower ends for making connection with other units of equipment and having a central longitudinal passage I I to communicate with and form a continuation of fluid passages provided in such other equipment as the bit E and collar A. In the particular case illustrated the threaded parts at the ends of the body ID are in the nature of threaded sockets. For example, it may be considered that the socket at the uppermost end of the body receives the pin projection I8 on the lower end of the drill collar A while the socket I6 at the lower end of the body receives the pin IQ of a bit E. In accordance with my invention the body is provided intermediate its ends'with a somewhat enlarged portion 20 with upper and lower threaded end portions 2| and 22.
The-upper collar H is applied to or threaded on the upper end orthreaded portion 2! of the enlarged body part 20 and it is preferably a simple annular ring-like element provided with a flat downwardly facing lower end or shoulder 25 and having a plurality of circumferentially spaced radially projecting blades 25. The collar ll may, in practice, vary widely in size, that is, in axial extent, and diameter, it being preferred generally to construct it so that it is applicable to the body H] to, in eifect, form a rigid shoulder thereon with the shoulder portion 25 eifective to take upward thrust from the rest M. The blades 25 on the collar ll may vary widely in number. arrangement, and design, it being preferred, ordinarily, "to provide a limited number of blades spaced-a substantial distance apart so-that there1 is ample circulation space between them and the forward'or leading edges 28 of the blades are preferably sharpened or fashioned to have effective cutting action when it is necessary that they serve to out the well formation in order to clear a passage for movement of the guide therethrough.
The. lower collar 12 is. mounted. on or applied to the lower threaded portion 22 of the body enlargement 2B and it may correspond, generally, with the upper collar H in that it may be an annular member with suitable cutting blades 26 thereon. The particular collar t3- shown in the drawings is similar in form and construction to the collar H in that it has blades 28 with cutting edges 28 and it is applied to the body to serve as a stop for the rest 44. The collar I2 stops downward movement of the rest on the body.
The particular collar i2 shown in the draw:
ings is provided at its lower end portion with an inwardly projecting flange 39 which stops against a downwardly facing shoulder 3! at the lower end of the enlargement 20. In accordance with my invention I provide means for locking the collar !2 on the body so that it will not shift longitudinally thereof or so that it cannot work around and thus become unthreaded. In the particular case illustrated-grooves 32- and 33 are provided in the body It and the collar l2 to register when the flange 30 is engaged with the shoulder 3| and an access opening 3 5 communicates with the channel formed by the grooves 32 and 33 so that looking balls 35 can be arranged in the channel as shown in Fig. 8. A plug 36 normally occupies the opening 34.
The sleeve 13 which is a bearing sleeve is slidablycarried onthe middle portion of; the body, that is, on the enlarged portion Zfibetween the threaded ends 21- and 22, and is clamped or confined between the collars H and I2. In'the preferred arrangement the lowerend 3,? of the sleeve rests on the upper end of the collar 12 and lugs 38 project from the collar to engage in notches in the lower end of the sleeve to lock the sleeve against rotation relative 'to the collar. The. upper end of the sleeve bears against the shoulder 25 provided at the lower end of collar H: and the collar H is preferably threaded tightly onto threaded portion 2! so the sleeve is clamped tight between the collars.
In accordance with the preferred form of my invention, considering. the equipment to be operated in the usual righthand direction, the thread of portion 2 i is pitched left-handed so that any tendency for the collar ll to work or shift during operation is such as to cause it to move toward collar H and consequently clamp the sleeve between the collars. I may, if desired, provide suitable stop or locking means for collar II. For instance, in the drawings I haveshown stop screws 40 carried by the collar I! so that they can be set against the body It.
The rest is carried by the sleeve Hi to be rotatable thereon and also movable longitudinally thereof, and being on the sleeve it is confined between the collars II and I2. The rest is a tubular part somewhat shorter than the space between the collars. In the preferred construction the rest has a central bore 4| lined with a suitable bushing 42 having suitable bearing engagement on the sleeve 13. The bushing 42 is retained at the lower end of the rest by aninwardly projecting fian e43 and at the upper end ofthe rest-by a thrust ring 44;;
75 the formation of the well in cases where it is Y In accordance with the preferred form of my invention the thrust ring 44 is formed separate from. the other parts of the rest and is detachably securedto the upper end of the rest by suitablefastening means such as screw members 45;. The upper side or face 46 of the ring 44 is finished to: have bearing engagement with the shoulder-25 of collar H, as shown in Fig. '7. The ring 44 thus serves both to retain the bushing 42 in place and also as a releasable bearing memher acting between the upper end of the rest and the lower end of collar H since during normal operation the rest. will tend to move up on the body and will consequently bear against the lower end of the collar I I.
In accordance with my invention I preferably provide the exterior of the rest with a plurality of: longitudinal grooves or channels 50, which channels divide the exterior of the rest. into a plurality of'bearing surfaces '51. In practice the channels 50 maybe somewhat spirally pitched, as shown in the drawings, and they may be of such sizeand number as to provide adequate circulation past the guide. By spirally pitching the channels the rest l4 will rotate somewhat as it moves longitudinally in the well bore so that wear on the bearing surfaces 5| is evenly distributed around the. rest.
In accordance with my invention the bearing surfaces 51 of the rest are designed to rest or seat on the Wall'of the, bore in, the manner illustratedin Figs. 1, 2 and 3: of the drawings, and in practice the rest may remain in the bore without rotating while the body It rotates within the rest, in ordertodrive the bit E. A limited amount of rotation of the rest occurs, however, as therest moves longitudinally of the well bore as abovedescribed.
In Figs. 9 and 10 of the drawings I have illustrated a. rest construction somewhat different than that; above described. In this form of my invention the rest has a tubular body it with projecting ribs 63' thereon having outer bearing surfaces 60. The rib bodies are of suitable resilient material such as rubber, or like material, reinforced by suitable bowed springs 6|. The surfaces of the rest are formed by the outer surfaces of the ribs. and, are backed up by the springs 6|. The springs, are preferably anchored at one end, for example, to the upper end of the body as by screws 62 and they depend outwardly and then inwardly where they slidably engage the lower end of the body as shown in Fig. 10. The springs 6| are preferably confined or embedded in the rubber ribs 63 which ribs. may be moulded onto the body of the rest and around the springs and joined. integrally thereto. The body of the rest may have suitable chambers or recesses 64.- in its exterior to receive the springs and the ribs. The springs may be. of any suitable strength and the ribs may be of such size and hardness as to afford effective support for the rest. However, the bearingsurfaces 6B are such as to depress or yield under extraordinary conditions or pressures so that the rest will freely move longitudinally of the wellibore when necessary.
The springs 6i being anchored at their upper ends, will tend to collapse when the tool is moved upward or isbeing retracted from the well bore.
It will be observed that. the collars II and i2 at each end of the rest are positively driven or rotate with the body Hland therefore with the bit and drill collar, and it will be apparent that the. bladesv on the collars will serveto work on 7 necessary to cut clearance or to provide a passage for proper movement of the guide in the bore. For example, as the drilling advances, should the bit become somewhat undersize or under gauge the blades 26 of the lowermost collar will engage the formation and serve as reaming cutters to allow advance of the equipment. In other cases Where the well bore may build up above the guide or guides, or where a caving condition may occur, the blades of the uppermost collar or collars will act effectively to cut away the formation or the built-up material, in order to allow for withdrawal of the equipment from the well. E
It is also particularly important to note that the rest is somewhat shorter than the space between the collars II and i2 making it possible, if necessary, to reciprocate the body I within the rest and efiect jarring of the rest to dislodge it, should it become stuck in the well bore By I providing a guide with resilient bearing surfaces the jarring action when necessary will readily dislodge it. This is an important feature of the construction since a structure effective as a guide and of such size as to substantially fit the well bore, may,in some cases, have a tendency to become slightly stuck or lodged, requiring a slight jarring action in order to Work it loose.
From the foregoing description it will be apparent that I have with the guide construction described, provided a structure that can be used to particular advantage in situations such as are illustrated in the drawings. With the guide that I have provided I am able to effectively control the lcutting action of the bit to cut a straight perpendicular well bore, to cut a straight deflected well bore, or to increase or to decrease the deflection of an inclined well bore at a desired rate. By using drill collars of substantial length and suitable flexibility I am able to bore wells with a. minimum of lateral off course deflection. I have also provided a guide structure which is not subject to becoming lodged in the well bore.
Having described only a typical preferred form and application of my invention, I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art and fall within the scope of the following claims:
Having described my invention, I claim:
1. Well drilling apparatus for operation by a drilling string including, a drill collar, a guide coupling the drill collar to the lower end of the drilling string, a bit, and a guide couplin the bit to the lower end of the drill collar each guide including a central body forming a coupling part, spaced collars on the body, and a rest rotatable on the body between the collars, the rest being substantially shorter than the distance between the collars to be shiftable longitudinally of the body and having a plurality of channels in its exterior establishing spaced bearing parts to engage the wall of the well bore, both of the collars having circumferentially spaced cutting blades projecting therefrom.
2. A guide of the character described including, an elongate central tubular body, spaced collars on the end portions of the body, and an elongate tubular rest member rotatable on the body between the collars, one of the collars having cutting blades projecting therefrom, the rest havingbearing engagement'from one end to the Ot1l81fOIlthe-b0dY."' i 1 3. A guide of the character described including, an elongate central tubular body, spaced collars on the body, and an elongated tubular rest member rotatable on the body between the collars, one of the collars having cutting blades projecting therefrom, the rest member having bearing engagement throughout its length on the body and being shorter than the distance between the collars to be shiftable lengthwise of the body.
4. A guide of the character described including, an elongate central body, spaced collars on the body, a bearing sleeve on the body extending between the collars, a bushing rotatable and slidable on the sleeve between the collars, and an elongate tubular rest member coextensive with the bushing and shiftable therewith between the collars.
5. A guide of the character described includ ing, an elongate central body, spaced collars on the body, a bearing sleeve on the body held between the collars, and a rest member rotatable on the sleeve and shiftable thereon between the collars, the rest member having a bushing therein extending from one end to the other and operating on the sleeve.
6. A guide of the character described including, an elongate central body, spaced collars threaded on the body, a bearing sleeve on the body engaged by and held tight between the collars, and a rest member rotatable on the sleeve and shiftable thereon between the collars, the rest member having a thrust ring attached to its upper end to bear on the lower end of the uppermost collar.
7. A guide of the character described including, an elongate central body, spaced collars threaded on the body, a bearing sleeve on the body clamped between the collars, and a rest rotatable on the body and shiftable longitudinally thereof between the collars, the rest including a bushing bearing on the sleeve and a thrust ring at its upper end engaging. the lower end of the uppermost collar.
8. A guide of the character described including, an elongate central body, spaced collars threaded on the body, a bearing sleeve on the body clamped between the collars, and a rest rotatable on the body and shiftable longitudinally thereof between the collars, the rest including a bushing bearing on. the sleeve and a thrustring at its upper end engaging the lower end of the uppermost collar, the rest having Iongitudinal channels at its exterior forming spaced resting parts, and the collars having circumferentially spaced cutting blades projecting therefrom.
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|U.S. Classification||175/306, 175/406, 175/325.2, 384/129|
|International Classification||E21B17/00, E21B17/10|