US2184817A

US2184817A - Motor drill for oil well casings and the like

Info

Publication number: US2184817A
Application number: US267889A
Authority: US
Inventors: Harold R Sharp
Original assignee: Individual
Current assignee: Individual
Priority date: 1939-04-14
Filing date: 1939-04-14
Publication date: 1939-12-26
Anticipated expiration: 1956-12-26

Description

Dec. 26, 1939. H. R. SHARP 2,184,817

MOTOR DRILL FOR OIL WELL CASINGS AND THE LIKE Filed April 14, 19:59 2 Sheets-Sheet 1 Inventor I32. Ska? Dec. 26,1939. H. R. SHARP 4,817

MOTOR DRILL FOR OIL WELL CASINGS AND THE LIKE Filed April 14 1959 1 2 Sheets-Sheet 2 x-fn? In venior 5&0? M

A ttnrneus Patented Dec. 26, 1939 UNITED S ATES MOTOR DRILL FOR OIL WELL OASINGS AND THE LIKE Harold R. Sharp, Waterloo, Iowa, assignor of onehalf to Ray M. Sharp, Waterloo, Iowa Application April 14,1939, Serial No. 267,889

1 Claim. (01. 255-4) This invention relates to a' well boring device, the general object of the invention being to provide means for boring the well in such a manner that it can be cased as the boring proceeds as the cutting means are so formed as to make a hole of greater diameter than the casing, said cutting means contracting to permit the boring means to be removed from the casing without Pulling the casing.

Another object of the invention is to provide an enclosed electric motor for driving the shaft which carries the expansible and contractible cuttingfmeans, with means for guiding the enclosed motor by a bottom "casing section. Another object of the invention is to provide means for cooling the motor assembly by fluid which is circulated through the well to remove the cuttings therefrom.

-This invention also consists in certain other features of construction and in the combination and arrangement of the several parts to be hereinafter fully described, illustrated in the accompanying drawings and specifically pointed out in the appended claim., In describing the invention in detail, reference will be had to the accompanying drawings wherein like characters denote like or corresponding parts throughout the several views, and in which: Figure 1 is a view showing the lower section of a well casing in longitudinal section and the drilling assembly in elevation.

Figure 2 is a bottom plan view of the drill head. a

Figure 3 is a longitudinal sectional view. through the upper portion of the motor assembly. Figure 4 is a similar view \through the lower portion of the motor assembly.

Figure 5 is a section on the line 55' of Figure In these drawings the numeral I indicates a lower section of a we1l casing, said section being provided with the interior vertically arranged guides 2 and the numeral 3 indicates a housing of a motor assembly which is provided with longitudinally extending ribs 4 for engaging the guiding means 2 so that the housing is supported for sliding movement in the housing i and is held against turning movement therein. An electric motor is located in the casing 5 which is 60 supported in spaced relation in the casing 3 by the lugs 6, the motor including the fields 'I and the armature 8 attached to the shaft 9, The shaft is provided with the anti-friction bearing means shown generally at III in the upper part I. of the casing 5 and. a similar bearing means II in the lower part of the said casing and upper and lower packing means l2 are associated with each bearing means so as to prevent any liquid or moisture entering the casing 5. The upper end of the casing 5 is closed by a cap l3 and a 5 conical member I is fastened to the cap l3 and a conical cap I5 is threaded to the upper end of the housing 3 and has a threaded reduced cylindrical end l6 for receiving the lower end of a. tube line which is used to introduce fluid, 0 such as drilling mud into the housing 3. This fluid is directed by the conical part It into the space between the casing 5 and housing 3, the fluid passing through said space and escaping at the bottom of the well and then this fluid 15 passesupwardly between the housing 3 and the casing l to the top of the well. The lower end of the shaft passes through a cap or cover plate I! inthe bottom of the casing 5 and an annular collar l8 and a cup-shaped member l9 are fas- 20 tened to the cap I1 by the bolt 20: The inner circumference of the member It forms a conical ball race for the anti-friction means 2| and a stub shaft 22 passes through the lbwer end of the member l9- and has a cup-shaped part 23 25 on its upper end which fits over the lower end of the shaft 9 and is slidably connected with the said lower end ofthe shaft 9 by means of the key member 24 fastened to the lower end of the shaft 9 and having its teeth engaging key- 30 ways in the member 23. The upper end of the member 23 forms a conical ball race and the anti-friction means 2i are held between this ball race and the race formed by the inner circumference of the member l8. 35

A drill head 26 is fastened to the lower end of the stub shaft 22 and isformed with the slots 21 in its lower face in which are located portions of the elongated bar-like bits 28, each of which has its inner end pivoted to the head 26 as shown 40 at'29. While the drawings show two of these hits it will now be understood that as many bits can be used as are necessary or desired.

As will be seen the stub shaft 22 which carries the drilling means has limited sliding movement 45 on the motor 'shaft 9 and this movement is resisted by the anti-friction means 2| and thus strain on the 'motor shaft 9 is relieved. The current for the electric motor is conducted to the same by suitable conductors passing through a cable, a portion of which is shown at 30.

As will be seen the section I of the well casin will prevent rotary movement of the housing 3 while permitting the said housing to be moved vertically. The bits or cutters 28 when expanded by resting on the bottom of the well will cut a hole of greater diameter than the diameter of the casing l.so that the casing can be fed downwardly as the hole isbeing bored, it being understood that the section I is moved downwardly.

as the well is being bored and other sections are placed on the top of the section I as the depth of the well increases, all the sections remaining in place after the boring has been completed. Pressure is applied to the motor assembly and therefore to the cutting means through means of the tubing connected with the nipple l6 and used for feeding fluid into the device. As before stated this fluid will pass between the housing 3, and

casing 5 and will flow into the bottom of the well and then pass upwardly between the housing 3 and casing l, dislodging the cuttings from the well. Any time that it is desired or necessary the housing 3 with the parts associated there with can be removed for as soon as the member 3 is lifted the bits will drop so that they can pass through the casing I and, of course, the

member 3 can be inserted into the casing I by having the bits swing downwardly so that they will pass through said casing i. As soon as the drill head hits the bottom of the well the bits or cutting members 28 will swing outwardly and thus cut a hole of greater diameter than the diameter of the well casing.

It is thought from the foregoing description that the advantages and novel features of the invention will be readily apparent.

It is to be understood that changes may be made in the construction and in the combination and arrangement of the several parts provided that such changes fall within the scope of the appended claim.

casing in the housing and spaced therefrom to form a passage between itself and the housing for the passage of the said liquid, an electric motor in the casing, means for closing the ends of the casing in a liquid-tight manner, antifriction means for the shaft of the motor, a shaft' section extending from the lower end of the motor casing, means for slidably connecting said shaft section with the motor shaft, a thrust bearing at the upper end of the shaft section,'a head 1' on the shaft, cutting means carried by the head for cutting a hole of greater diameterthan the casing section, means whereby said cutting means I will move downwardly and inwardly when the head is lifted off the bottom of the well to permit the cutting means to pass through the well casing. the liquid introduced into the housing flowing through said passage into the bottom of the well and then passing upwardly between the housing and the well casing.

HAROLD R. SHARP.