US 2890859 A
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Description (OCR text may contain errors)
June 16, 1959 M. A. GARRISON TURBINE WELL DRILLING APPARATUS Filed Feb. 25. 1957 INVENTOR. MARION A. GARRISON BY 1"!!! Illlli 1/ Arro NEY 2,890,859 TURBINE WELL DRILLING APPARATUS Marion A. Garrison, Denver, Colo., assignor to Eastware Oil Well Survey Company, Denver, Colo., a corporation of Delaware 2 Application February 25, 1957, Serial N 0. 642,238
Claims. (Cl. 255-16) This invention relates to the art of well drilling wherein the prime mover is an axial flow turbine and is placed at the lower end of a string of pipe or conduit for actua tion by the drilling fluid circulated downwardly through the conduit. More specifically, the invention relates to turbine drilling wherein the drill pipe and outer shell of the turbine, particularly during directional drilling, may be rotated to eliminate the well known tendency of a motionless drill pipe to stick in the hole and wherein a survey instrument such as one for bottom hole orientation may be passed through the turbine to immediately adjacent the bit and thus permit more accurate and efiicient survey readings. i
The concept of turbine drilling is Well known, but there are several problems encountered in present day activity in this field. Firstly, it is known that motionless drill pipe associated with present turbine drilling, especially in soft sedimentary formations, has a tendency to stick in the bore and this happens especially when bent subs or the like are employed between the turbine and drill pipe during directional drilling because in such instance any rotation of the drill pipe interferes with the orientation. Furthermore, survey readings in turbine drilling are usually taken above the location of the turbine in the hole. For example, in employing the bent sub technique, due to the ferrous material of the turbine the nearest practical point that a survey instrument employing a compass or other element sensitive to magnetic material can be placed with respect to the bottom of the hole may be in excess of 35 or 40 feet from the drill bit, and thus the survey never truly reflects the condition at or adjacent the hole bottom.
It is an object of this invention to provide a turbine drilling assembly wherein in making a survey the surveying equipment may be passed through a hollow rotor shaft of the turbine whereby the reading takes place immediately adjacent the drill bit.
Another object is to provide an assembly as defined in the preceding paragraph wherein the top end of the hollow rotor shaft is provided with valve means which is closed automatically during drilling operations but which is automatically opened upon cessation of fluid circulation such as when a survey is to be made.
It is also an object to provide with apparatus of the type described a deflecting tool interposed between the bottom of the turbine and the drill bit for causing drilling at an angle with respect to the remaining bore and wherein any survey instrument may be passed directly into the deflecting tool for obtaining accurate and efficient readings for use in tool orientation.
Yet another object of the invention is to provide a turbine drilling unit as defined in the last paragraph wherein the hollow rotor shaft thereof may be coupled for rotation with the outer shell of the turbine and in turn the drill pipe during operations other than drilling, such as during directional survey operations, to permit proper tool orientation.
Finally, it is an object of this invention to provide a turbine drilling unit along the lines of the preceding ,para-.
. Patented June 16, 1959 shell of the turbine and the drill pipe, irrespective of the coupling means, may be rotated independently of the turbine rotor to prevent Without orientation interference any sticking of the drill pipe and the shell in bore formations.
The construction designed to carry out the invention will be hereinafter described together with other features thereof, and will be more readily understood from a reading of the following specification and by reference to the accompanying drawing forming a part thereof wherein an example of the invention is shown and wherein:
Figure 1 is a longitudinal view partly in. section of the: top portion of the drilling unit embodying this invention;
Figure l-A is a longitudinal view partly in section of the bottom portion thereof;
Figure 2 is an enlarged sectional detailed view of a portion of the unit shown in Figure l;
Figure 3 is an enlarged sectional view taken along the line 3-3 of Figure 2;
Figure 4 is an enlarged view taken along the lines 44; and
Figure 5 is a longitudinal sectional view of a modified portion of the unit.
In the drawings the numeral 1 designates the usual drill pipe or drill stem which is adapted to extend through a well bore W. A turbine unit is generally represented at T, a drill collar or sub at 2, a deflecting tool at 3 and a drill bit at 4. As will be explained hereinafter the deflecting tool 3 would be eliminated in connection with straight drilling, and in such instance the drill bit 4 would be connected to the end of sub 2 in conventional manner. Of course, circulating fluid in the form of mud causes the turbine T to impart the necessary rotation for drilling to the bit 4. i p
In practicing the present invention various types of turbine constructions can be utilized, the only requirement being that the rotor be hollow as distinguished from solid and the top part of the turbine rotor must incorporate structure along the lines of or equivalent to that shown in Figure 2 and which will be fully explained hereinafter. The turbine T as illustrated includes a thrustzbearing section 5, a turbine section 6 and a lower bearing section 7. The entire sectionsinclude a common outer shell 8 forming an extension of pipe 1 as shown, although the shell 8 could be separately connected by any suitable means .to V the drill stem 1. For more proper and complete description of a general type of turbine that may be used and thedetails of the Various sections 5, 6 and 7 reference is made to United States patent in the name of G. P; Wagner,'N0.
2,588,311, and to the October, 1956 issue page B4O of the magazine The Petroleum Engineer, the turbine 1 being essentially the same as theturbo drill describedin the latter. There are many other prior art illustrations of turbine constructions that could form a part of this invention, such as those of United States Patents 2,613,917 and r 2,340,738 in the names of Postlewaite and Dilley respectively.
Briefly, the upper bearing section 5 acts both as a thrust and as a radial bearing for the turbine rotor shaft 9 and this bearing consists of a number of disc type surfaces similar in design to conventional journal type thrust bearings. A The intermediate section 6 includes matching numbers of rotors 11 and stators 10 of which each pair constitutes one stage of the turbine, andof course the stators 10 are integral with the outer shell 8 and the rotors 11 are integral with the rotor 9. The bearing section 7 acts as the lower .radial bearing and as a seal between the stationary and ,above, references. Assuming for the moment that th'e to of rotor 9 is closed then any circulating fluid pumped down from the surface of the well will travel in the direction of the arrows shown in Figures 1 and 1-A and in conventional manner cause rotation of depending .portions 13 which is integral with shaft 9 and drill bit 4.
Illustrated as connected to portion 13 by threaded engagement as at 14 is the drill collar or sub 2 which, of course, as shown is also hollow and is made ofnon-magnetic material such as K-Monel. The deflecting tool 3, if employed, is connected by suitable means to the bottom of sub 2 and from this tool depends the bit 4 and if tool 3 is eliminated bit 4 would be connected directly to the bottom of collar 2. Various types of deflecting tools 3 may be employed and as an example of a suitable tool reference is made to United States Patent No. 2,819,040 issued January 7, 1958 in the names of William G. James et al. and assigned to the same assignee as the present invention. As shown this tool 3 includes a deflecting shoe or element 15 designed to ride over the wedge 16 and, of course, the element 15 controls the angle of diviation. Numeral 17 merely represents a stabilizer for stabilizing the tool in the well W and numeral 18 the outer sleeve of the tool.
As will be pointed out hereinafter, assuming a survey operation is to take place beneath section 7 and immediately adjacent bit 4 then means must be provided for automatically opening the top of hollow shaft 9 which is normally closed during mud circulation, the hollow diameter of shaft 9, sub 2 and portion 13 being of a size to permit passage of a survey instrument therethrough. Suitable such means is shown in detail in Figures 2 and 4 and includes a flap valve 21 which assumes the dotted line position of Figure 2 when there is mud circulation and drilling and assumes the solid line position when there is no mud circulation and the survey operations are to take place by passing the survey equipment through the hollow shaft 9. Numeral 22 represents a stationary base which is annular and hollow so as not to interfere with fluid circulation between shell 8 and rotor 9 and is integral with:
the outer turbine shell 8. This base 22 may take various forms and is for the purpose of supporting the lower convolution of a coiled spring 23, the purpose of which is to urge a piston 24 upwardly within shell 8. The piston 24 is also annular and hollow and of course it provides a fluid seal with the interior wall of shell 8. Depending from this piston are, as shown in Figure 4, spaced rods 25 which, at their lower end, are provided with teeth 26 for meshing with gears 27, the latter in turn each being journaled on stub shafts 28 extending from shell 8 and valve 21 being keyed for movement with the gears 27. Thus, members 25 and gears 27 form a rack and pinion drive for causing the valve 21 to move to and from the solid and dotted line positions of Figure 2 and the valve is designed to create a fluid seal with rotor 9. Various structures may be em ployed for operating valve 21 and of course such should be designed not to interfere with the flow of the circulating fluid. It will be noted that the piston 24 provides a reduced opening 29 and thus there would be a pressure differential when the circulating fluid reaches the.
piston. This pressure differential during fluid circulation will cause the piston 24 to move downwardly overcoming the bias of spring 23 to cause the rack and pinion drive to close the pressure differential valve 21, or in other words to cause this valve to move to the dotted line position. When fluid circulation is stopped the spring 23 will automatically open the top shaft 9 by causing flap valve 21 to move to the solid line position.
' Referring to Figure 3 in particular there is shown an overrunning clutch C. This type of clutch may take various forms and as shown in a ratchet type clutch. Adjacent its top the tube 9 is provided with teeth 31 which are adapted to be engaged by the. pawl 32 that is pivotally connected at 33 to the outside shell 8 and its spring biased by means 34 into engagement with teeth 31. The various" functions of this clutch. will be set forth hereinafter, but.
it should be apparent that when shaft 9 is rotated at a high speed in the direction of the arrow of Figure 3 and the turbine is designed for operation in this direction, the teeth 31 will pass by the pawl 32 without causing any corresponding movement of shell 8 On the other hand during this high speed rotation of shaft 9 the drill pipe in cluding the shell 8 will be caused in the usual manner to be moved due to the torque reaction of the turbine. However, during certain surveys such as when a deflecting tool 3 is employed, means must be provided to rotate sub 2 and in turn the outer sleeve 18 'of the tool '3 in order to properly orient the deflecting element 15, it being understood that at this time there is no fluid circulation, the turbine prime mover is not in operation and the valve 21 is closed. By slowly rotating drill pipe 1 and the shell 8 to the right as viewed in Figure 4 the pawl 32 will engage the teeth 31 and cause corresponding movement of sleeve 18 and thus the deflecting element 15 will be oriented in accordance with the survey made. Accordingly the clutch C provides a locking or coupling means for causing rotation "of the turbine rotor 9 during orientation of a deflecting tool 3.
Operation of apparatus Assuming the apparatus is as shown in Figures 1 and l-A and that there is straight bore drilling, then the 'deflecting tool 3' would be eliminated and the bit 4 connected directly to the collar 2. Circulating fluid such as mud, which is normally used in oil well drilling, is then pumped down from the surface through the drill pipe 1 under pressure. For reasons explained, this causes downward movement of the piston 24 and a closing of the valve 21 and the mud then flows through the turbine, passing downwardly from stage to stage to drive the rotor 9 and in turn the collar 2 and the bit 4 to drill the hole. The mud, of course, then flows out through the usual holes in the drill bit and upwardly around the outside of the stem or drill pipe. As explained, during high speed rotation of the rotor 9 in the normal direction of the rotor rotation, the clutch C would not be engaged and thus the drill pipe 1 and in turn the shell 8 may be allowed to rotate backwards from torque reaction to prevent any sticking of the pipe or drill stem in the bore, or may be caused to rotate slowly at the surface of the drill pipe to prevent sticking and/or to reduce the effective speed on the bit.
Now assuming that is it desired to run in through pipe 1 by a wire line or the like a survey instrument such as a drift indicator for recording the inclination of the well bore in controlled vertical drilling or to make a reconnaissance drift survey or other types of surveys. With past turbine drilling apparatus it is only possible to run in the survey instrument to a point spaced from the upper end of the turbine as the instrument generally contains one or more elements sensitive to ferrous material or the like from which the turbine, at least in part, is made,
and unless this is done it would interfere with an accurate survey reading. On the other hand, even with this spacing the instrument is generally at least 35 to 40 feet from the drill bit and thus the survey never truly re-' flects the condition at or adjacent the hole bottom. With the apparatus of the present invention, as soonas the fluid circulation is stopped the valve 21 opens, in the manner mentioned, to permit the survey instrument to be lowered through the turbine rotor 9 and into the collar 2 which is of non-magnetic material so that there will be no material interference with survey readings.
Thus, the survey may be made substantially immediately adjacent the drill bit to truly reflect the condition at the bottom of the hole.
In connection with directional drilling prior turbine drilling apparatus generally employs a bent sub above the turbine and here again any directional survey must be: made above the turbine and a substantial distance from the bit. Furthermore, the bent sub after it is is lost anyway once drilling starts due to turbine torque reaction in effect winding up the pipe), and thus there is a great tendency for the drill pipe to become stuck, especially in soft sedimentary formations. The present invention overcomes these difliculties and this will be explained by assuming that a tool such as deflecting tool 3 is interposed between the bit 4 and collar 2 and that it is desired to orient this tool for the desired directional drilling. This is accomplished by shutting down fluid circulation which permits the directional survey to be made by lowering the instrument into tool 3 in the manner described, and thus here again the survey is made immediately adjacent the bit. To properly position the defleeting shoe 15, means must be provided for rotating the tubular rotor 9 to the desired position and this is accomplished by the clutch C. After the reading is made if drill pipe 1 and in turn shell 8 is rotated slowly to the right as viewed in Figure 4, then the clutch C will engage and cause corresponding rotation of the rotor 9 and in turn sleeve 18 and shoe 15 to properly position the shoe for desired directional drilling. Of course, prior to orienting shoe 15 pipe 1 may be rotated slowly to the left to avoid sticking. Now, if drilling is again started the valve 21 will be automatically closed and of course drill pipe 1 and shell 8 may be slowly rotated if necessary without being concerned with loss of bore orientation as would be the case in the event a bent sub were employed.
When closed, valve 21 as shown in Figures 1 to 4, would be exposed to wear due to the rotation at a high speed of rotor 9. To prevent this, various modifications may be made such as positioning, as shown in Figure 5, the hollow stationary head 35 at the upper end of rotor 9 with the latter arranged for relative rotation with respect to the head in view of bearing 36 which is similar to bearing 12. Of course, with such an arrangement the clutch C would be positioned as shown. To insure that the head 35 will remain stationary upon rotation of rotor 9 and not be influenced by any frictional drag or the like, there may be provided three heavy screw-like members spaced 120 degrees apart and affixed to stem 1 and head 35. Two of such members are shown at 37 in the drawing and of course it is to be understood that such is only an example of a typical means that may be employed to insure the head 35 being maintained stationary.
The foregoing disclosure and description of the invention is illustrative and explanatory thereof and it is clear that the apparatus achieves the objects enumerated. 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 this invention.
1. In a. turbine well drilling unit, a hydraulic axial turbine interposed in the drill pipe and arranged to be driven by the fluid, said turbine including an outer stator shell and a hollow rotor shaft, a non-magnetic hollow sub through which the mud passes connected to the lower end of said shaft and a drill bit connected for movement with the sub and arranged to be rotated by the shaft, a valve for closing the upper end of the shaft during mud circulation through the turbine, and means operable upon release of fluid circulation for automatically opening the valve and upper end of said shaft whereby a survey instrument may be inserted throught the shaft and at least into said collar and adjacent the bit for surveying the well being drilled.
2. A unit as defined in claim 1 wherein a deflecting tool is interposed between the sub and bit for causing drilling at an angle with respect to the remaining bore, and wherein there is provided a clutch operable upon rotating the shell in one direction for coupling the shell with said shaft whereby rotation of the shell in the one 6 direction during release of fluid circulation causes similar rotation of the shaft.
3. A unit as defined in claim 2 wherein said clutch is of the ratchet type and includes a plurality of teeth on the exterior of the rotor shaft adjacent the top thereof and a spring biased pawl pivotally connected to the interior of said shell and engageable with said teeth.
4. A unit as defined in claim 1 wherein the automatic means comprises a piston movable in response to drilling fluid to one position, means for causing the piston to move to a second position upon cessation of fluid circulation, and means interposed between the piston and valve for causing the latter to close upon the piston assuming its first position and to open upon the piston assuming its second position.
5. A unit as defined in claim 4 wherein the last named means includes at least one member depending from said piston and having teeth on a portion thereof, a shaft extending from the interior of said shell and a gear journaled on said shaft in meshed engagement with said teeth, said valve being of the flap type and keyed for movement with said gear.
6. Well drilling apparatus comprising drill pipe, a hydraulic turbine at the lower end of said pipe arranged to be driven by the circulating fluid, said turbine including an outer stator shell and a hollow rotor shaft, a drill bit on the end of said turbine opposite the pipe, and a non-magnetic collar interposed between the bit and turbine whereby fluid may pass through said pipe to rotate said shaft, collar and bit, and automatic controlled means operable by and responsive to fluid circulation for closing the shaft upon fluid circulation through said apparatus and for opening the shaft upon cessation of fluid circulation.
7. Well drilling apparatus as defined in claim 6 wherein said last named means includes a pressure differential valve operable when there is fluid circulation to close the upper end of the shaft and operable upon the cessation of fluid circulation to open the upper end of the shaft whereby a survey instrument may be inserted through the shaft and at least into said collar and adjacent the bit for surveying the well being drilled.
8. Apparatus as defined in claim 7 wherein the automatic means further includes a piston movable in response to drilling fluid to one position, means for causing the piston to move to a second position upon cessation of fluid circulation, and means interposed between the piston and valve for causing the latter to close upon the piston assuming its first position and to open upon the piston assuming its second position.
9. Apparatus as defined in claim 7 wherein a deflecting tool is interposed between the sub and bit for causing drilling at an angle, and wherein there is provided means operable upon rotating the shell in one direction for locking the shell with said shaft whereby rotation of the shell in the one direction upon cessation of fluid circulation causes similar rotation of the shaft.
10. Apparatus as defined in claim 7 wherein a stationary hollow head is interposed between the upper end of the shaft and the valve, said shaft being rotatable relative to said head.
References Cited in the file of this patent UNITED STATES PATENTS 1,665,058 Hanna Apr. 3, 1928 2,167,019 Yost July 25, 1939 2,254,641 Bannister Sept. 2, 1941 2,786,535 Boer et a1. Mar. 26, 1957 FOREIGN PATENTS 304,936 Switzerland Apr. 1, 1955 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent Non 2,890,859 June 16, 1959 Maxion A, Garrison It is hereby certified that error ap o'ears in the a'bwve number-ed patent requiring correction and that the said Lea'bt rs Patant should. read as correct-ed below In the grant, lines 2 and 12, and. in "the he ding to the printed specificatien, lines 3 and. 4, name of assignee, for Eastware Oil Well Survey Company" read m Eastman Oil Well Survezy Company o Signed and sealed this 26th day of April 1966.,
' KARL H, AXLINE ROBERT C. WATSON Commissioner of Patent: