US2567451A - Drilling apparatus - Google Patents

Description

W. H. SMITH DRILLING APPARATUS Sept. 11, 1951 2 Sheets-Sheet 1 Filed Sept. 14, 1948 INVENTOR.

WILL/19H /7. 5/1/77) Sept. 11', 1951 W. H. SMITH DRILLING APPARATUS 2 Sheets-Sheet 2 Filed Sept. 14, 1948 Patented Sept. 11 1951 UNITED STATES PATENT OFFICE DRILLING APPARATUS William H. Smith, Sullivan, Ind.

Apphcation September 14, 1948, Serial No. 49,159

6 Claims. 1

This invention relates to a drilling apparatus of the rotary type adapted to operate at the lower end of a housing and supporting casing for drilling vertical holes in the earth of the desired depth and diameter for the purpose intended.

The principal feature of. the invention consists in providing a motor driven drilling and pumping unit which may be conveniently lowcred into and removed from the bottom of the casing, to continuously discharge cuttings above ground so as to permit inspection and appraisal of the current cuttings at all times during the drilling operation. This is accomplished by providing a unitary structure consisting of a submersible electric motor having a centrally disposed drive shaft connected at its lower end through suitable reduction gears with an expanding cutter, and at its upper end with a multistage turbine pump. The unit is suspended in the casing by a suitable hose in communication with the discharge end of the pump through which the cuttings are discharged.

A further feature of the invention resides in the interlocking keys and keyways interposed be= tween said unit and the housing casing for preventing relative rotation therebetween. Said keys and keyways are so formed and related to each other as to interlock the unit inv the casing against axial displacement therebetween in the working direction, while permitting their axial displacement and disengagement to remove the unit from the casing when not working. Thus, upon downward pressure being applied to the casing to efiect the cutting operation, said keys and keyways are positively interlocked. How ever, upon elevating the casingthe said keys and keyways may be freed to permit angular displacement therebetweenv and free the unit from the casing so that it may be elevated therefrom. The said keys and. keyways may be extended longitudinally or at any angle found advanta= geous in operation.

Another feature of the invention resides in the tapered race and packing extending about the lower end of the casing to expand and wedge against the wall of the hole to protect the strata being cut from the hazard of cave insand disturbances of the higher strata and the above strata water, and also permit at all times the elevation for inspection and appraisal of the current cuttings from the hole.

The full nature of the invention will be understood from the accompanying drawingsand the following description and claims:

Fig. 1 is a schematic illustration of the apparatus both below and above ground with the cas- Fig. 3 is a section taken on the line 33 of Fig. 2.

Fig. 4 is a central vertical sectional view of the lower end of the casing with the unit removed.

Fig. 5 is a central vertical cross section through the packer.

Fig. 6 is a section taken on the line 66 of Fig. 5 with parts omitted.

In the drawings there is shown a well drilling apparatus for drilling a hole It] in the earth. Said apparatus includes a motor driven cutting and pumping unit. Said unit comprises a submersible electric motor I mounted in a cylindrical housing l2 and including the motor field l3, rotor l4, and centrally disposed shaft l5 carried by the rotor to extend axially of the housing [2. The lower end of said shaft is connected to a planetary gear train including the planetary pinions l6 rotatably mounted on the spider l1 and meshing with the ring gear iii. The spider I1 is provided with a downwardly extending stub shaft [9 rotatably supported by suitable bearings carried by the housing [2. The lower end of the stub shaft I9 is secured to a chuck 20 for receiving an underreaming rotary cutting device 2| of the well known roller or scraper type.

The upper end of the motor shaft I5 is keyed to a series of pump impellors 22 of which one is herein shown, adapted to operate in the pump housing 23 and having a series of discharge passages 24. Said pump housing, shown in Fig. 1, is of the three stage turbine type with the intake end thereof provided with a strainer 25.

The upper end of the turbine pump is provided with a nipple 25 for receiving a discharge hose 2'! which also serves as a cable for raising and lowering the said unit. The motor H is electrically connected with the power cable 28.

Said unit is adapted to operate within the well casing 39, which casing is of the desired diameter for the type and purposes of the hole being drilled and is of the usual sectional length, generally about twenty feet. As is customary, said sections of the casing are joined to increase the over-all length thereof as the well increases in depth. For this purpose there is provided the usual above ground structure which may be in the form of a mast or scaifolding schematically v illustrated and indicated at 3|.

Said scaffolding may he provided with an operating cage 3.2 suspended by a hoisting cable 33 which may be raised and lowered by a drum and winch. As the depth of the hole progresses the casing with the cage is lowered until the casing is substantially below ground; whereupon the cage is raised and an additional section of casing is placed for lowering.

The lowermost casing has its lower end formed with peripherally disposed and spaced keyways 34 as best shown in Figs. 3 and 4, which keyways are of inverted U-shaped arrangement with their open portions terminating at the lower edge-of 3 the casing. The lower end of the housing I2 is provided with a series of longitudinally extending and peripherally spaced keys 35 adapted to have a sliding fit within the keyways 34.

The above described arrangement is such that during the cutting operation the drilling unit carrying the keys 35 will be interlocked against rotation relative to the casing 30. Thus, the unit will be held steady and rigid within the casing which in turn will be firmly held against rotation within the hole, as hereinafter described.

The keys 35 will also be interlocked within the keyways against vertical displacement in one direction. The inverted U-shaped keyways bear upon the upper ends of the keys so that downward force applied to the casing will be transmitted to the drilling unit during the drilling operation. At the top or upper end of the inverted U-shaped keyway 34 may be constructed and secured, if found desirable, coil springs 34a against which the upper end of the keys 35 come to fit, for the purpose of absorbing vibration that may be caused by the cutting operation. However, when it is desired to remove the drilling unit from the casing, the casing may then be slightly elevated until its keyways disengage the keys 35. A slight angular displacement between the keys. and keyways may then be effected by slightly rotating the drilling unit, whereupon it may be raised with its keys 35 passing upwardly between the keyways 34. When it is desired to mount an additional section the drilling unit may then be lowered until its keys lie below the keyways and the cutting head 2| rests on the bottom of the hole. The casing is then slightly elevated, if necessary, and lowered after a slight turning movement of the unit with the keyways sliding over and embracing the keys 35, or the drilling unit may then be raised to engage the keys and keyways.

Surrounding the lower end of the casing and secured to 'the exterior wall thereof, there is a tapered sleeve 36 about which there is slidably mounted an expanding spring packer 31 suificient in size and spread to frictionally bind against the wall I9 of the hole for sealing the upper part thereof from the lower portion being cut to exclude excess water and any cave ins therefrom. Said spring packer is of a character having an outer spring metal shell with a core of rubber or rubberized material. By reason of the tapered sleeve 35 the packer will become wedged between the casing and wall of the hole to provide an effective seal therebetween as the casing is lowered, but will slide downwardly about the sleeve out of such wedging and sealing engagement upon the casing being raised to free its keyways 34 from the keys 35 of the unit. Thus, the initial friction between the Wall of the hole and the packer 31 will be increased as the drilling progresses and the packer is forced upwardly relative to the tapered sleeve, while tending to be relieved upon elevating the casing.

In operation the drilling unit may be lowered from the top level of the ground to operating position by the supporting cable 2! to the desired depth wherein its keys 35 will be below the inverted U-shaped keyways 34 of the casing. Thereupon the unit is rotated to such position relative to the casing that it may be raised, or the casing lowered with the keys and keyways engaged. In this position the cutting head 2| will be slightly below the lower end of the casing so that when the casing is lowered and the cutting head comes in contact with the bottom of the hole, pressure applied thereon by the weight of the casing will expand the cutters so that upon operating the motor they will cut the hole to the required diameter. During the cutting operation the packer will protect the lower portion of the hole and the cuttings will be pumped upwardly between the casing and the unit housing to the strainer 25 01' the pump 23. They will be discharged above ground through the cable discharge hose 21. If, due to the depth of the hole, additional pumping requirements are necessi tated, one or more additional pump units may be added in series with the pump units 23. Proper application of pressure to the cutting unit may be determined through the employment of weight measures showing the dead weight and decrease thereof, or through the employment of an electric ammeter to indicate the motor load. In event additional water is required for the cutting operation, it may be added down the open hole or injected into the casing 30 to seep through to the bottom. However, this is seldom necessary as the formation being cut generally supplies an excess of water to be excluded.

When it is desired to withdraw the cutting unit from the casing, the casing may be slightly raised to free the keyways and keys, 34 and 35; whereupon said unit may be slightly rotated to a position where its keys are positioned between the keyways so that it may be raised from the casing. Thus the unit may be readily removed from the casing at the completion of the cutting operation or for the purpose of adding additional casing sections.

From the above it will be noted that multiple and diameter decreasing lengths of easing are eliminated, as only one span of casing is necessary and may be of any diameter determined to be the most applicable. A concisely round hole will be drilled, eliminating the drift from perpendicular and the hazard of caving and disturbances of terrestrial strata, and the breaking of natural water and gas seals. The above strata water is excluded from the working horizon by the packer, thereby permitting at all times the elevation for inspection and ap'praisal of current cuttings from the hole. Furthermore, elimination of all pressure from the strata being out either from the above strata static Water pressure or operational applied pressure. The casing may be left in the hole for permanent installation as the currentexamination of cuttings may be employed to determine the most opportune time to discontinue drilling and eliminate the necessity of cementing or otherwise sealing the hole for proper operation. By increasing the spread of the cutters, reservoirs of concise size and depth may be cut at any chosen horizon for the accumulation of liquids, thereby increasing the productivity of liquid flow from the chosen strata and the ultimate volume recovery.

A modified form of packer is shown in Fig. 5 and Fig.5, said packer comprising a plurality of laminated spring members I31 peripherally mounted about the outside of the casing 30 near the extreme lower end thereof. The loose end portions of said members extend upwardly and outwardly and then slightly inwardly to avoid catching or binding against the wall of the excavated hole.

Within the laminated curved members there is fitted a lining of rubber or rubber composition I38 for excluding excess water from above the water bearing strata. Whenever the height of the column of water above any given portion or point of the packer is greater than the hei ht of the column of water underneath any given portion or point of the packer then there will be exerted downward a pressure in direct proportion to the height of the column of water above the packer is causin it to bind more tightly against the wall of the excavated hol e, thus pro viding a seal against the passage of additional water from above the packer.

if additional stabilization of the lower end of the casing is necessary it may be provided by three or more curved equally spaced spring members I39 pivotally and peripherally mounted upon the outside of the casing with their extreme spring spread sufficient to contact and bind by friction against the wall of the excavated hole and with their opposite end portions outwardly turned providing movement against the wall of the housing casing as contraction and expansions requires.

The invention claimed is:

1. A drilling apparatus of the rotary type adapted to be positioned at the end of a well casing, including a motor driven pumping and cutting unit of generally cylindrical form and of less diameter than said casing to provide a space thereabout and within said casing for the passage of cuttings, said unit comprising an electric motor having an axially disposed shaft driven thereby, an expanding cutter secured to the lower end of said shaft, a turbine pump rotatable with said shaft having its intake communicating with said space, and a discharge connection communicating with said pump to extend through said casing for delivering cuttings from said space above ground during the drilling operation.

2. A drilling apparatus including a casing adapted to extend downwardly in the hole being drilled, a motor driven cutting and pumping unit of less diameter than and spaced inwardly of said casing movable therethrough, said unit comprising an electric motor having an axially disposed shaft, an expanding cutter secured to the lower end of said shaft, a pump rotatable with said shaft having its intake open to the space between said casing and unit, said pump discharging into an above ground outlet connection, and interlocking keys and keyways on said unit and easing, respectively, slidabl engageable to prevent relative rotation therebetween, said key- Ways having obstructions to prevent relative axial displacement of said keys in one direction when engaged while permitting axial displacement in the opposite direction for disengagement to permit said unit to be withdrawn from said casing.

3. A drilling apparatus including a casing adapted to extend downwardly in the hole being drilled, a motor driven cutting and pumping unit of less diameter than said casing movable therethrough, said unit comprisingan electric motor having an axially disposed shaft, an expanding cutter secured to the lower end of said shaft, a pump rotatable with said shaft. having its" intake within said casing and an above ground outlet connection, and a series of interlocking elements on said unit and easing, respectively, one series of said elements being generally U- shaped to provide pockets for slidably receiving said other series of elements and prevent relative rotation between said unit and easing, said U-shaped pockets preventing axial relative displacement of said unit and casing in one direction while permitting displacement in the opposite direction for freeing said elements from interlocking en agement,

4. A drilling apparatus including 4 a casing adapted to extend downwardly in the hole being drilled, a motor driven cutting and pumping unit of less diameter than said casing movable theretlirougli, said unit comprising an electric motor having an axially disposed shaft, ex= panding cutter secured to the lower end of said shaft, a pum rotatable with said shaft having its intake within said casing and an above ground outlet connection, a series of in verted U-shaped keyways provided on the inner surface of said casing adjacent the lower end thereof, and a series of coacting keys provided on the lower end of said unit for interlocking engagement therewith.

5. A drilling apparatus including a casing adapted to extend downwardly in the hole being drilled, a motor driven cutting and pumping unit of less diameter than said casing to provide a passage space therebetween and movable therethrough, said unit comprising an electric motor having an axially disposed shaft, an expanding cutter secured to the lower end of said shaft, a pump rotatable with said shaft having its intake communicating with said space within said casing and an above ground outlet connection, and a spring encased compressible packer mounted on the lower end of said casing to extend radially from the outer wall thereof into sealing engagement with the wall of the hole being drilled.

6. A drilling apparatus including a casing adapted to extend downwardly in the hole being drilled, a motor driven cutting and pumping unit of less diameter than said casing to provide a passage space therebetween and movable therethrough, said unit comprising an electric motor having an axially disposed shaft, an expanding cutter secured to the lower end of said shaft, a pump rotatable with said shaft having its intake communicating with said space within said casing and an above ground outlet connection, a tapered sleeve secured about the outer periphery of said casing adjacent the lower end thereof to flare upwardly and outwardly therefrom, and a compressible packing ring slidably mounted about said sleeve for spreading and wedging engagement with the wall of the hole being drilled upon the casing being moved downwardly therein.

WILLIAM H. SMITH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 196,220 Gordon et a1 Oct. 16, 1877 1,350,059 Blackwell Aug. 17, 1920 1,380,203 Glick May 31, 1921 1,406,348 Corrigan Feb. 14, 1922 1,501,481 Frazier July 15, 1924 1,555,918 Friesen Oct. 6, 1925 1,717,271 Simmons June 11, 1929 1,736,254 Davis Nov. 19, 1929 1,777,961 Capeliuschnicoff Oct. 7, 1930 1,799,559 Hunicke Apr. 7, 1931 1,880,217 Simmons Oct. 4, 1932 2,105,091 MacKay Jan. 11, 1938 FOREIGN PATENTS Number Country Date 2,443 Great Britain 1904 626,830 Germany Mar. 6, 1936

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