US2245750A - Well boring bucket and method of boring wells - Google Patents

Description

J. R. BETTS- 2,245,750

WELL BdRING BUCKET ND METHOD OF BORING WELLS June 17, 1941.

Filed Nov. 25, 1938 INVENTOR. John R. Bcffs ATTORNEY.

Patented JuneI'Z, 1941 WELL BORING BUCKET AND METHOD OF BORING WELLS John R. Betta, Kearney, Nebr.

Application November 25, 1938, Serial No. 242,330

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My invention relates to the sinking of wells and it includes both a novel form of well boring apparatus and a novel method of boring wells.

One of the objects of the invention is the provision of a well boring tool in which kinetic energy is stored up to be utilized in boring the well either with or without the use of additional motive power.

Another object is the provision of a well boring bucket having a well boring auger therein together with means for holding the bucket against rotation during the rotation of the auger.

Another object is the provision of a well boring bucket which is adapted to penetrate the soil and to encase the soil, the bucket being adapted to be lifted for removing the soil from the bucket at points outside the well cavity.

Another object is the provision of a well boring bucket having openings with closures in the sides thereof whereby the soil within the bucket may be discharged through the openings.

Another object is the provision of a well boring bucket having an auger within the bucket at the lower extremity thereof and having means for forcing the water out of the bucket through the auger.

Another object is the provision a well boring bucket having depending peripherally arranged spurs for preventing the rotation of the bucket during the well boring operation.

Another object is the provision of a well boring bucket having peripherally positioned brackets at the lower edge of the bucket with means for interchangeably securing 'spurs thereto.

Another object is the provision of an auger within a nonrotatlng bucket, the auger being associated with flapper valves for admitting soil into the bucket but preventing friable soil from falling out when the auger ceases to rotate.

Figure l is a view in vertical section of the well-boring bucket.

' Figure 2 is a vertical sectional view of the auger and associated parts.

Figure 3 is a view in elevation showing the modified form of spur used on the bucket.

Figure 4 is a cross-sectional view of the lower portion of the bucket and showing particularly some of the details of the auger.

Figure 5 is a vertical sectional view of the lower end of the bucket and a portion of the auger with the flap removed.

The bucket I0 is cylindrical in form and it is closed at its upper extremity as shown in Figure l. The bucket is divided into two compartments by means of a partition H, the upper compartment being closed while the lower is open at its lower extremity. Centrally positioned in the bucket is a vertical shaft l2 which has bearings at l3, l4 and ii. The upper extremity is connected to any suitable prime mover such as the electric motor l6 having connections at H for driving the motor. The electric motor i6 may, of course, be replaced by any other suitable means for driving the shaft l2. A brace i8 is secured to the inner walls of the bucket for the purpose of supporting the motor l6. The entire device is constructed so that the lower end portion of the bucket is designed to penetrate the soil and to cncase the soil to be discharged from the lower compartment after drawing the bucket out of the well cavity. In the operation of the bucket, the auger is rotated by the shaft i2 which is secured to the auger but the bucket must be held against rotation during the boring operation. For this reason I provide a plurality of spurs I 9 peripherally arranged about the lower end of the bucket and adapted to enter the soil in advance of the auger. These spurs are designed solely for resisting the tendency of the bucket to rotate, but this tendency is also resisted to some extent by the friction of the side walls of the cavity. The bucket is to be withdrawn from the cavity at intervals in order to remove the soil which has accumulated in the lower compartment of the bucket. In order toconveniently remove the soil from the bucket, I provide a plurality of gates 20 which are hinged at 2| to be continuous during operation with the side walls of the bucket. Other gates 22 are similarly hinged to the bucket and they facilitate the insertion of a crowbar or other tool for dislodging' soil which has become packed in the lower compartment of the bucket.

While the shaft I2 is to be driven by the motor 16, the arrangement is such that the shaft it during the boring operation is driven through the kinetic energy of the plurality of weights 23. These weights 23 are in disc form and of very heavy metal; They are keyed to rotate with the shaft i2 and they are provided with collars at the upper and lower surfaces to contact with each other. In the operation of the device the entire bucket is first positioned above the well cavity and supported on any suitable platform in the vertical position. The spurs l9 engage the platform to prevent rotation of the bucket I0. Power is applied to the shaft i2 which causes the weights 23 to rotate with the shaft. This rotation is necessarily slow at the start but the speed may be increased until the desired speed to extend the boring operation at the-bottom of the well cavity as will be subsequently described. The rotation of the auger shaves oi! the soil at the bottom of the cavity and lifts it into the lower compartment of the bucket. This rotation may be supplemented by the motor ll or it may automatically stop when the energy in the weights 23 is exhausted. The bucket is then raised by means of any suitable hoisting mechanism engaging the swivel 24 until the bucket again rests on the platform. After dislodging and removing the soil from the bucket, the process is repeated until the desired depth of the well has been attained.

It is to be understood that the auger will function at all speeds, and while the high speed is of course desirable, it is not essential for cutting. The extreme weight of the rotating element while desirable is not essential in so far as the alignment of the tool is concerned, but it is essential in the wheel element for this weight combined with the rotativ'e speed determines the amount of kinetic energy stored in the wheel battery, which energy will be delivered to the auger when the latter contacts the soil.

The auger at the lower extremity of the shaft I2 is similar to the prior augers employed in boring wells, but owing to the high speed at which it operates, there are a number 'of departures from the prior augers' and these departures are of vital importance in the successful operation of the boring bucket. As will be seen in Figure 2, theauger includes a cylindrical portion 2! having an external diameter which is slightly less than the internal diameter of the casing Hi. This cylindrical portion is open at two or more vertical linm and is out turned and beveled to form cutting edges 28 as shown in Figure 4. The rotation of the auger results in the cutting edges 28 shaving of! the vertical walls of the cavity and pushing the soil inwardly and toward the center of rotation of the auger. At the bottom of the cylindrical portion 25 is an under reamer consisting also of two or more blades 21 which are designed to shave oil the soil in the bottom of the well cavity and to transport that soil upwardly in the lower chamber of the casing III. In the ordinary auger, the movement of the soil is slow due to the slow rotation of the shaft. Where the shaft is rotated at the speed which I contemplate employing, the movement of the soil on the blades 21 is exceedingly rapid so that the tendency is for the soil to be hurled up toward the top of the lower chamber of the bucket. To accentuate this movement I turn the discharge end of the blades 21- upwardly as best shown at 8 in Figure 2. In addition, I employ valves 28 which are hinged at 30 to the auger and which tend to assume their open position in response to the pressure of the incoming soil supplemented by the centrifugal force during the rotation of the auger, but which close automatically under the weight of the soil in the bucket portance of this resides in the retention in the bucket of sand and other free flowing soil.

The spurs i 8 may be fixed in position as shown in Figure 1 and they may be so employed when the soil is fairly uniform from the top to the bottom of the well cavity. Such conditions are very seldom encountered and it is usually found that the soil varies between rather -ide limits from exceedingly hard to very soft soil. A spur which is suitable for onekind of soil might be wholly unsuitable for another. If the spurs are very long they will function perfectly in soft sand, but they are apt to be broken off in hard soil that is encountered. On the other hand, if the spurs are short and stubby, they will provide suff iicient friction in very hard soils but they will not function in soft soils. For this reason I provide interchangeable spurs as shown in Figure 3. The upper portion ll of the spur is welded or otherwise secured to the casing III with the lower end of the spur positioned above the under reamer. The lower portion 82 of the spur is adapted to be securedto the portion 3| by any suitable releasable connectionsuch as the male and female screws in the parts 3i and 32.- In this man- 7 ner it is possible to provide spurs 32 of various when the rotation of the auger ceases. The imlengths so that the change may be made quickly and easily while the bucket is outside of the well cavity.

The partition is relatively water tight and air tight. The result is that the bucket functions,

much as a diving bell does with the result that there is usually a very heavy pressure inside the lower compartment of the bucket. Some of this compressed air will seep out through the packing about the shaft l2 and into the upper chamber of the bucket, but water and mud cannot as a rule pass from the lower chamber into the upper chamber. There are times in the boring of a well when it is desirable that the air pressure be materially increased in the lower chamber of the bucket. For this reason I provide an air connection 33 for forcing air under high compression into the upper chamber of the bucket. To permit this compressed air to pass from the upper chamber into the lower chamber, I provide a check valve 84 which prevents the upward passage of air but permits the air to pass down. The compressed air is turned into the bucket on its descent and while it is rotating at high speed. When the auger enters the water plane the air tends to form a large bubble keeping the auger free from everything but air until it comes into contact with the soil.

The shaft I2 is of fixed length for delivering the power from the prime mover to rotate the auger at the bottom of the shaft. In.this way I avoid the diiliculties encountered when a slow moving shaft must be lengthened in accordance with the depth of the well cavity which is being bored. Not only is this difficulty avoided, but the far greater difllculty of maintaining the bore in a straight line is also avoided. A slow cutting auger without much weight behind it is very apt to become slightly inclined when uneven soil is encountered and this inclination may grow to serious proportions to result in misalignment of the bore. Owing 'to the high speed of the shaft and the great weight on the shaft my well bucket resembles the movements of a top. Such a top if it has suilicient speed is held normally in the vertical position. When the bucket is ready to be lowered into the well cavity it is 2,245,7so suspended vertically and the result is that the great weight and the high speed impart a gyroscopic effect on the deviceas a whole to maintain the initial direction of the shaft. No dimculty is therefore encountered in misaligned well cavities. The auger is subjected to the constant weight. of the discs '23 which firmly maintain the auger in a constant pressure against the bottom of the well' cavity. The speed at which the discs 23 rotate. which may be at the periphery as high as two miles per minute, causes a very rapid rotation of the auger, theeflect being that of a rotating pile driver which delivers a rotating blow.

The operation of the well boring bucket in principle is the same regardless of-the character of the soil, but this operation varies slightly open at itslower end and divided into upper and lower compartments, an anger in the lower compartment atthe lower end thereof,'said auger being adapted to raise the soil removed into said lower compartment, means in the upper compartment for rotatingsaid auger, a check valve between said upper and lower compartments depending upon the variations in the soil. Whenever a very soft soil is encountered, the lower compartment of the bucket is apt to fill before the energy in the weights is exhausted. In passing through such strata it is merely necessary to lower the bucket before the maximum speed hasbeen acquired so that the energy in the weights is exhausted before the soil compartment of the bucket iscompletely filled. Other soils are so refractorythat the energy in the weights may be exhausted with only a small charge of soil in the bucket in which case the energy in the weights may be supplemented by the operation of the motor. When only a small portion of the bucket is filled in one operation, it is not necessary that the bucket be withdrawn and its contents be discharged every time the rotation ceases. In such cases it is advisable to repeat the operation as many times as is necessary by elevating the bucket to-a point where the auger no longer engages the soil and to start the operation of the motor. This may be repeated as often as necessary for accumulating the desired amount of soil in the bucket before raising and emptying the bucket.

When the auger operates through a stratum of water, the bubble of compressed air will expel the water through the bottom of the bucket to thus facilitate the descent of the bucket until the auger again comes into contact with the soil at the bottom of the well cavity. The doors are'provided with any suitable latches 33' but the air'pressure is further held by means of rubber or any other suitable gaskets 34 so that 1 the air can escape only through the bottom of the bucket. d

It should be noted that the universal coupling 35 is directly under the motor and directly over the wheel battery and in line with the vertical axis of the entire mechanism. Being thus balanced and suspended, the gyroscopic effect of the rapidly rotating heavy weights is to maintain the travel of the auger in a straight line direction. It should also be noted that the cutting edges 26 cut a cylindrical bore whose diameter is slightly greater than the diameter of the bucket; thus facilitating the descent of the bucket;

I claim as my invention:

1. A well boring bucket comprising av casing open at its lower end, a revolving auger at the lower end of said casing adapted to'raise the soil removed into said casing, means for introducing air under pressure into the lower portion of said casing to force water accumulated during the boring operation out of the lower end of the casing, and means for rotating said auger.

2. A well boring device comprising a casing opening only in the direction of the lower partment, and means for introducing air under pressure into'the upper compartment to passinto the lower compartment and force water accu mulated during the boring operation out of' the lower end-of the compartment.

3. A method of boring a well which comprises A providing awell boring bucket having a boring tool therein and a mass secured to said boring tool, rotating said boring tool and mass while said bucket is out of contact with the bottom of the well. until said mass and said boring tool attain a high rate of speed, and then lowering said bucket into contact with the bottom of the well without any means for effecting the continued rotation of the boring tool other than the kinetic energy of therotating mass.

4. A method of boring a well which comprises providing a well boring bucket having an auger therein and a mass secured to said auger, rotating said auger and mass while said bucket is out of the well until said mass and said auger attain a high rate of speed, then lowering said bucket into the well without any means for efiecting the continued rotation of the boring tool other than the kinetic energy of the rotating mass, and withH drawing said bucket after said kinetic energy has been expended.

5. A well boring bucket comprising a non-rotating casing open at its lower end, a revolving auger at the lower end of said casing adapted to raise the soil removed into said casing, said auger being of substantially the same diameter as said casing and being substantially immovable with respect to said casing in a longitudinal direction, means for rotating said auger, and means rigidly secured to the lower endoi' said casing and projecting longitudinally downwardly therefrom closely adjacent said auger to engage the soil adjacent that 'being bored to prevent rotation of said casing, said last named means having a relatively small transverse'dimension so as not to hinder the downward movement of said casing and auger.

6. A well boring device comprising a non-rotating casing open at its lower end, a revolving boring tool at the lower end of said casing said boring tool having a boring portion of substantially the same diameter as said casing and being substantially immovable with respect to said casing in a longitudinal direction, means in said casing for revolving said boring tool, and spurs rigidly secured to the lower end of said casing and projecting downwardly therefrom closely adjacent said boring tool to engage the soil in advance of that being bored to prevent rotation of said casing.

7. A well boring device comprising a non-rotating casing open at its lower end, a revolving boring tool at the lower end of said casing. said vanee of that being bored to prevent rotation of said casing. said spurs being detachably secured to said casing to permit the attachment or spurs of the proper length for the soil being bored;

8. A method of boring as well which comprises providing a well boring bucket having a boring tool therein, a mass secured to said boring tool, and an electric motor for rotating said mass and boring tool, energizing said motor while said bucket is out 01' contact with the bottom of the welluntil said was and said boring tool attain a high rate of speed. deenergizing said motor, and then lowering said bucket into contact with thebottorn of the well without any means for efiecting the continued rotation 01 the boring tool other than the kinetic energy of the rotating JOHN R. BE'I'I'S.

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