US3502543A - Means for operating an auger with additive supply - Google Patents

Description

March 24, 1970 B. w. SEWELL. 3,502,543

MEANS FOR OPERATING AN AUGER WITH ADDITIVE SUPPLY Filed July 28, 1966 3 Sheets-Sheet 1 INVENTOR. BEN W. SE WELL ATTORNEY March 24, 1970 B. w. SEWELL MEANS FOR OPERATING AN AUGER WITH ADDITI Filed July 28, 1966 INVENTOR.

BEN W. SEWELL A TTORNE Y March 24, 1970 5, w, s Ew 3,502,543

MEANS FOR OPERATING AN AUGER WITH ADDITIVE SUPPLY Filed July 28, 1966 3 Sheets-Sheet 5 k; 2 8 Q r 5 a: D l E m o g 2 CL V NOT ENOUGH ADD/TIVE PERCENT OF ADD/T/VE INCREA$E INVENTOR. BEN W. SEWELL BY 4% W ATTORNEY United States Patent 3,502,543 MEANS FOR OPERATING AN AUGER WITH ADDITIVE SUPPLY Ben W. Sewell,, 4700 Mohawk Blvd., Tulsa, Okla. 74115 Filed July 28, 1966, Ser. No. 568,458 Int. Cl. E21b 21/04 US. Cl. 17524 3 Claims ABSTRACT OF THE DISCLOSURE An anger is connected to a power source and actuated to be rotated and advanced. Material is particulated and delivered to the flights of the auger. A source of fluid lubricant is arranged to supply lubricant between the auger flights and the particulated material. A control system coordinates the rate of material and the rate of material volume and the rate of fluid lubricant delivered to maintain a desired ratio.

The present invention relates to means for improving the performance of a conveyor of auger form. More particularly, the invention relates to control of the rate at which an additive is combined with material to be transported, the mixture improving the function of the auger conveyor in transporting the material from one point to another.

The conveyance, or transport, of material by an auger is common and well known. The material may be delivered to the rotated auger at any preselected point along the length of the auger and the spiral flight, or flights, will advance the material along the length of the auger for delivery at a second preselected point.

Material which is to be conveyed by an auger must have, or be given, some degree of partioulation. Some material has suflicient particulation in its natural state. However, it is often necessary to particulate the material with some means. For example, a drill bit may be the means attached to the end of an auger drill stern and is applied to an earth formation to particulate the material. Also, a rock crusher may be employed to reduce the size of rock, particulate it, for transport on an associated auger.

After material which is to be transported is particulated it must be given other properties, as a body, in order to be conveyed efliciently by an auger. The compaction of particulated material should be adjusted and some form of additive associated with the material to give the resulting combination plasticity, moldability, and surface lubricity for contact with the auger flights. An auger, as a mechanical conveyor, requires a certain degree of these properties to function efliciently. These properties serve to contrast the nature of rotary drilling with the nature of drilling which uses an auger.

A bit on the end of a rotary drill string generates cuttings. A fluid is injected down the hole to contact the cuttings. However, large volumes of drilling fluid, mud, are supplied, enough to flush the cuttings from the hole. This mode of operation is quite different from the mode of operation of an anger drill stem with which the present invention is employed.

I have discovered by analysis of actual test data that the quantity of the desired additive that is combined with the material to be transported must be carefully controlled for optimum transport efliciency by an auger. The penalty for poor control of the quantity of the additive can be great. Too little additive will cause the mixture to stick to the auger. A stuck auger could result in the loss of an expensive drill stem. Excessive additive, on the other hand, will result in a loss of efliciency in the transport of the mixture and could become a major expense of the drilling operation.

3,502,543 Patented Mar. 24, 1970 When the auger is employed with a drill bit, and is used as a drill to penetrate earth material, I may simply employ water as the additive, with or without other ingredients. The water may be passed down the bore of the auger stem to mix with the cuttings generated by the bit. It is not contemplated that the water be supplied at the pressure, and in the quantity, to flush the cuttings from the bore hole. With my invention, water may be supplied in relatively small quantities and the conveying, or transporting, of the cuttings by the flight carried out efficiently.

Whatever the nature of the material conveyed, or transported, by an anger; whatever the nature of the additive selected; the problem to be faced is how to regulate the supply of the additive to maintain conveying efliciency. More specifically, the problem becomes one of maintaining the ratio between the rate of additive volume supplied and the rateof material volume conveyed.

A principal object of the invention is to supply sub stantially the minimum volume rate of additive to material supplied an auger to convey the material with satisfactory efliciency.

Another object is to select and maintain the ratio of the rate of additive volume supplied to the rate of material volume conveyed by an auger.

Another object is to control the rate of the volume of additive supplied to material to be conveyed by an auger drill in accordance with the rate of linear travel of the stem of the auger.

Another object is to control the rate of the volume of additive supplied to material to be conveyed by an auger drill in accordance with the rate of rotation of the stem of the auger.

Another object is to control the rate of the volume of additive supplied to material to 'be conveyed by an .auger drill in accordance with the power required to rotate the stem of the auger.

The present invention contemplates the supply of material to be conveyed by an auger and the supply of additive to the material being controlled to a desired ratio of their volume rates. The material may be supplied at a fixed, or variable, rate, and substantially the minimum rate for the additive is established to enable the auger to convey the material with desired efliciency.

The invention more specifically contemplates an auger employed as a drill with a bit mounted on a first end and means for rotating the auger connected to the second end. The bit is directed so it will generate cuttings from material which is penetrated and additive is delivered near the bit so it will mingle with the cuttings and implement the advance of the cuttings smoothly by the surface of the flight as the auger rotates. The additive is delivered near the bit at a rate dependent upon the rate of penetration. The supply of additive is specifically disclosed as regulated by the function of a piston and cylinder attached to the auger so that the linear movement of the auger stem into the material penetrated establishes the rate of additive volume delivered near the bit; therefore, the ratio of the volume rate is maintained whether the penetration rate is constant or variable.

Other objects, advantages and features of this invention will become more apparent to one skilled in the art upon consideration of the written specification, appended claims, and attached drawings, wherein:

FIG. 1 is an isometric view of an anger, arranged as a drill for earth formations, with an additive supply system embodying the present invention;

FIG. 2 is an isometric view of an auger, similar to the anger of FIG. 1, disclosing another system for controlling additive; and

FIG. 3 is a graph representing the relation between the torque required to turn an auger in a mixture of particulated material and additive as the proportions between material and additive are changed.

DISCLOSURE SELECTED TO EMBODY AND ILLUSTRATE THE INVENTION The invention has utility in the operation of augers in all the varied forms of structure in which they may be incorporated. The auger may be employed simply as a conveyor of material, such as grain, from one point to another. The auger may be the stem of a drill generating a bore hole in an earth formation. However, the concept of the invention is a common denominator to both augers; a desired additive is combined with the material to be transported by the auger flights in a selected and maintained volumetric ratio.

Systematic investigation has determined the change in the plasticity, moldability and surface lubricity of particulated material mixed with a fluid additive. I have discovered a range of volumetric ratios of material and additive which is surprisingly significant to the transport of the mixture by an auger. At the outset I wish it to be clear that the specific embodiment utilized to disclose my concept is not to be construed as a limitation of my invention in any way.

Drilling structures are illustrated in the drawings. However, the auger of a drill represents any auger supplied material for transport and fluid additive for attaining and maintaining the efficiency of that transport.

THE GENERAL ARRANGEMENT OF THE DRILL- ING STRUCTURE OF FIG. 1

FIG. 1 specifically illustrates the invention embodied in an earth drilling unit 10. The unit includes an auger 11 with an axial bore 12 through its stem 13, spiral flight 14 mounted on the external surface of its stem, a bit 15 mounted on a first end of the stern and a power source 16 connected to the second end to rotate the auger. The bit generates cuttings 17 as it is turned in the earth formation 18. The generated cuttings are delivered to the surface of the flight which is adjacent the bit, and the rotation of the auger progresses the material thus delivered to the flight along the length of the auger.

The bit 15 is on the lower, or first, end of stem 13. On the upper, or second, end of stem 13 there is indicated a unit 16 connected to the stem to rotate it. Unit 16 can be an electric motor, however, fluid pressure conduits are indicated in FIG. 1 to suggest a hydraulic motor. The specific form of this power source is not important to the disclosure of the invention. A unit 16 is provided and mechanically linked to stem 11 through a gear box 19. A control of the speed of rotation is not shown. In this FIG. 1 the speed of rotation is presumed at least substantially constant.

Assuming the rotation of auger stem 13 to be constant, or substantially so, the auger is advanced along its axial length. Advanced, the bit 15 on the end of the stem will generate the desired cuttings and advance them up the hole by means of the flight 14.

In FIG. 1, the advance of the stem end bit is carried out by mounting the upper end of stem 13, gear box 19 and power unit 16 on frame 20. This frame 20 is then lowered under control as the bit rotates against the earth formation 18. The control of the lowering of the bit 15 determines the volume of the cuttings generated and conveyed by the auger flight.

Frame 20 is specifically advanced by attachment to rod 21. Also the frame 20 is guided in its advancement by the legs of mast 22. The power applied to rod 21 is developed from hydraulic cylinder 23 which is mounted on the top of mast 22.

Rod 21 is arranged inside cylinder 23 as a piston rod. Hydraulic fluidis then fed selectively to the top and bottom of cylinder 23 by control of valve 24. It would appear that this element of control is readily understood, being essentially the conventional diversion of hydraulic power fluid from a source to the upper and lower ends of cylinder 23. With predetermined power from the hydraulic fluid, valve 24 controls the direction and movement of auger stem 13 at a predetermined rate.

CONTROL OF ADDITIVE In FIG. 1 the volume of material generated for conveyance by the auger is established by the substantially constant rotation and the rate of advance of the auger and its bit. Therefore, we can move to a consideration of the rate of linear travel of frame 20 as an index of the rate of material volume delivered to the auger for conveyance up and out of the bore hole. This movement of frame 20 is then utilized directly to control the volume of fluid additive it is desired to mix with the cuttings to carry out the objects of the invention.

As set forth supra, the invention provides a link between the volume of material to be conveyed and the volume of fluid additive; their desired ratio is determined and maintained as the advancement of frame 20 is varied. Specifically, the frame 20 is mechanically linked to a supply of the desired additive.

In FIG. 1 the mechanical link includes sprockets 25, 26 and chain 27 connected to frame 20. Sprocket 25 is mounted near the top of mast 22. Sprocket 26 is mounted on a shaft 28 near the bottom of mast 22. The chain 27 is carried on both sprockets and attached to frame 20. As frame 20 travels down mast 22 to advance the auger bit, sprocket 26 and its attached shaft 28 rotates. The linear movement of frame 20, representative of the volume of cuttings generated at the bottom of the drilled hole, is converted into the rotary movement of shaft 28. This rotation is placed in direct control of the volume of additive by actuating a pump conveying the additive to its mixture with the generated cuttings.

In FIG. 1, bore 12 is provided along the axis of auger 11 to deliver the fluid additive near bit 15. This axial bore is disclosed as extending from bit 15 up to swivel 29. Swivel 29 is then disclosed as connected to a conduit 30 through which the fluid additive is forced by pump 31.

The suction of pump 31 is connected to conduit 32 which, in turn, is connected to additive supply tank 33. The speed of pump 31 controls the ratio of the volume of additive to the volume of material to be conveyed.

Pump 31 is mechanically actuated by shaft 34. Shaft 34 is coupled to shaft 35 through a clutch 36. Shaft 35 is, in turn, connected to shaft 28 through a variable speed transmission 37. Transmission 37 provides the means whereby the ratio between the rotation of shaft 28 and the rotation of shaft 35 can be selected. Therefore, pump 31 is actuated in predetermined proportion to the penetration rate of the auger drill. Should the nature of the conveyed material change, or the type of additive be changed, it might be desirable, or necessary, to change the ratio between the rates of material conveyed and additive supplied. Variable speed transmission 37 is a means with which the desired ratio can be selected, changed and maintained.

In operation of the auger, it is contemplated that through valve 24 the downward force on the bit 15 will be manually controlled. Whatever the variation of force, with a resulting variation of drilling rate, the volume of additive will be held in a predetermined desirable ratio to the volume of material conveyed up the hole by the auger. The volume of additive can be kept to substantially the minimum required yet the chance of sticking or jamrning of the bit will be obviated.

I have disclosed a simple, straightforward link between the volumes of additive and conveyed material. However, it is recognized that the speed of bit rotation also determines the volume of material generated and conveyed. The ower supplied unit 16 can be detected and utilized to control the volume of additive. In general, an increase CONDUCT ION OF ADDITIVE TO MIXING WITH J CONVEYED MATERIAL Up to this point, I have disclosed how the additive is controlled in its rate of delivery to the material to be conveyed. However, the system for conduction of the additive from a reservoir, or storage tank, to the cuttings does not require the bore 12 of stem 13 disclosed. The nature of the additive fluid may dictate an external conduit system on the auger from the swivel 29. The invention is in no way to be limited by the specific form of conduit system disclosed for the additive.

The specific form of apparatus disclosed would normally require only water as the additive. Water, mixed with cuttings from earth formation 18, is expected to produce the plasticity, moldability and lubricity required for eflicient conveyance by the flight 14. However, the characteristics of water might need variation with some types of earth formations. In any event, it is contemplated that some form of fluid will be conducted from a reservoir to near bit 1 5, controlled as has been disclosed.

THE GENERAL ARRANGEMENT OF THE FIG. 2 STRUCTURE As with FIG. 1, FIG. 2 discloses an auger included as part of adrilling structure. Unit 100 includes auger 101 with an axial bore 102 through stem 103. Spiral flight 104 is mounted on the external surface of stem 103, bit 105 is mounted on the lower end of stem 103 and a power source 106 is connected to the upper end of the stem 103 to rotate the auger and bit.

Bit 105generates cuttings 107 in turning and advancing in earth formation 108. The generated cuttings are delivered to the flight surface. Rotation of the auger progresses the material along the auger length. Power unit 106 is indicated in both drawings as a hydraulic unit. No

control of the power, to vary the speed of rotation, is

disclosed However, control of such power is obviously possible, and variation of the auger rotation and advancement will vary the material delivered to the auger flight 104 and advanced by the flight.

In an arrangement similar to that of FIG. 1, the upper end of stem 103 is mounted on frame 120. This frame is lowered, upder control, to determine the volume of the cuttings generated and conveyed by the auger flight. Rod 121 is the mechanical link between hydraulic power cylinder 123 and frame 120. Selective direction of hydraulic fluid to cylinder 123, through valve 124, controls the reciprocation of frame 120 along the legs of mast 122. The structures of FIGS. 1 and 2 are. comparable in the foregoing elements which have been generally described. The difference between the structure will now 'be disclosed in the control of the additive fluid mixed with the cuttings 107.

CONTROL OF ADDITIVE As in FIG. 1, the additive control in FIG. 2 is indexed to the rate of travel of frame 120, assuring a substantially constant rate of rotation of the auger by power unit 106. However, rather than control a pump for the fluid additive by the movement of frame 120, a feed cylinder 150 is actuated by the movement of frame 120.

Feed cylinder 150 is similar to power cylinder 123 in appearance. Also, both cylinders are mounted on the top of mast 122. Where power cylinder 123 is connected to frame 120 through rod 121, feed cylinder 150 has a rod 151 arranged as a piston within cylinder 150. In general this arrangement provides for cylinder 150 to be filled with fluid additive as frame is moved toward the top of mast 122. Then, as frame 120 is lowered by power cylinder 123, the fluid additive is forced from feed cylinder to the cuttings 107. As the rate of travel of frame 120 is proportional to the volume rate of cuttings generated, the ratio of additive volume and cuttings volume is maintained during the drilling operation and conveyance of the cuttings and fluid mixture by the auger.

CONDUCTION OF THE ADDITIVE As disclosed in connection with FIG. 1, the additive fluid from storage, or supply, tank 133 need not be conducted down the axial bore of stem 103. Some external conduit arrangement connected to stem 103 is feasible. Whatever conduit system is provided downhole, to cuttings 107, some structure equivalent to swivel 129 is desired as a junction with the conduit system between the supply tank 133 and the downhole conduit.

The fluid additive must be provided a path from tank 133 to feed cylinder 150 and from feed cylinder 150 to swivel 129. Conduit sections 152, 153 and 154 from the flow path for the additive from tank 133 to feed cylinder 150. Check valve 155 insures that the additive will not be forced from these sections 153 and 154 back into tank 133.

As additive is forced from cylinder 150, it will flow along the path provided by conduit sections 154, 156 and 157 to swivel 129 and the downhole conduit. Check valve 158 insures that no additive will flow from conduit section 157 back into section 154.

Return-flow conduit section 159 is connected between conduit 156 and conduit section 157 and conduit section 152 in order to provide a route for additive from cylinder 150 back to supply 133 when drill stems are being disconnected in order to avoid additive loss during such operation. Valve 160 is disclosed as a specific means between conduits 156, 157 and 159 with which to select the routes desired for the additive at any particular time.

OPERATION OF THE FIG. 2 ADDITIVE SUPPLY SYSTEM In FIG. 1 the additive supply rate to the cuttings was regulated through a pump linked to the frame driving the auger. Feed cylinder 150 is a simple form of pump linked to frame 120 comparable to pump 31 in FIG. 1. It is a relatively simple matter to change the cylinder 150 to select the size desired to feed the additive to cuttings 107. In all events, the fundamental concepts of the invention are embodied in both the structure of FIG. 1 and the structure of FIG. 2.

FIG. 3 GRAPH At the outset, I pointed to the requirement of some form of additive to be associated with particulated material for efficient conveyance by an auger. I also announced my discovery from analysis of actual test data that the quantity of the additive must be carefully controlled for optimum transport efliciency. The disclosure has heretofore been primarily devoted to the control problems of the additive. I now wish to give dramatic illustration of the need for this close control. The graph of FIG. 3 has been developed to show the critical nature of the control problem, the benefits to be gained and the penalty which can he suffered.

FIG. 3 is a simple graph of the values of torque required to actuate an auger to convey particulated material mixed with varying percentages of additive. The plot of torque against the variation of additive in the mixture is suitably legended in FIG. 3 to reduce the amount of explanation necessary.

In the beginning, comparatively little torque is required to rotate an anger in essentially dry particulated material. As the percentage of additive increases, the torque increases to a certain value. The mixtures becomes sticky,

clinging to the auger, balling up being the term commonly used to describe this accumulation on the auger surface.

The subjective slope of the curve will depend upon the nature of the particulated material and the characteristics of the additive. In general the curve will go up, the torque will increase. Past a certain point, as brought out with the FIG. 3 curve, the mixture will gain plasticity, moldability and surface lubricity which will sharply reduce the torque required to turn the auger.

Obviously, as the additive is increased, the torque will continue to decrease. However, the eflficiency of conveyance will reduce beyond a certain range of additive increase. Further, not only will the efliciency of conveyance reduce but additive will be Wasted. Therefore, there is the comparatively narrow range of ratios of the material and additive quantities which will give the results I seek with my invention. The graph depicts this range, and the disclosure method and apparatus attain, and maintain, this range.

CONCLUSION Further consideration of the teachings of the FIG. 3 graph have led me to the conclusion that my invention in ratio control is not limited to conveyance of the mixture by an auger, or even conveyance of the mixture. FIG. 3 demonstrates that the characteristics of the mixture vary considerably over a range of ratios and attainment and maintenance of the ratio within a selected range can be quite useful for purposes other than conveyance.

Within the preferred range of FIG. 3 the mixture will have high surface lubricity. A vehicle passing over the mixture will not have the mixture stick to it and impair its movement. Control over the ratio of additive and particulated material in the mixture will maintain this freedom of movement by a vehicle.

It is now logical to formulate that ratio control will maintain a desired type of contact between any mechanical means contacting, or working, the mixture. The means may, or may not, perform the work of conveyance. A conveying means may, or may not, be equivalent to the auger disclosed. In broad consideration my invention is embodied in the control of the ratio to attain, and maintain, desirable characteristics while some type of structure contacts the mixture in work.

From the foregoing it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove set forth, together with other advantages which are obvious and which are inherent to the method and apparatus.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

The present invention having been described, what is claimed is:

1. A system for operating an auger which is provided with at least one spiral flight, including,

an auger having at least one spiral flight,

a bit mounted on a first end of the auger which will particulate material it is desired to transport and deliver to the auger flight,

a power source connected to the second end of the auger to rotate the auger and progress the material along the flight surface,

a supply of additive,

a conduit system from the additive supply to the particulated material arranged to deliver additive for mixture with the material to provide the mixture with a plasticity and moldability and surface lubricity,

a means attached to the auger which gives linear travel to the auger,

and a connection between the auger and supply of additive which provides the additive at a volume rate proportional to the rate of linear travel of the auger.

2. A system for operating a wet auger drill, including,

an auger having an elongated hollow stem with at least one spiral flight mounted externally on the stern,

a bit mounted on a first end of the auger and arranged to engage material and deliver the material to the surface of the flight adjacent the bit,

a power structure connected to the second end of the auger so as to rotate the auger and cause the surface of the flight to convey the material away from the first end of the auger,

means to axially advance the auger,

a supply of fluid additive connected to the bore of the stem near the second end of the auger,

and a control means connected to the auger and the supply of additive and arranged to regulate the delivery of additive from the source to the bore of the stem in accordance with the axial travel of the auger.

3. The system of claim 2 wherein,

the supply of additive includes a cylinder in which the additive is stored,

and the control means includes a piston in the cylinder and on one side of the stored additive within the cylinder which is connected to the auger stem in such manner as to travel along the length of the cylinder as the auger travels axially and force additive ahead of the piston and down the stem bore to mix with the material delivered to the surface of the flight.

References Cited UNITED STATES PATENTS 424,266 3/1890 Buckingham 175-65 1,343,902 6/1920 Chapman 175-394 X 1,735,091 11/1929 Powers et a1. 173--75 1,969,533 8/1934 Pipes et a1 259-154 2,603,319 7/1952 Dyche 175-394 X 2,647,726 8/1953 Kirk 175217 X 2,810,550 10/1957 Cohen et al. 175-162 3,006,615 10/1961 Mason 259154 CHARLES E. OCONNELL, Primary Examiner I. A. CALVERT, Assistant Examiner US. Cl. X.R. l--65, 162, 217

Images