US3833071A

US3833071A - Apparatus and process for soil dewatering

Info

Publication number: US3833071A
Application number: US00356827A
Authority: US
Inventors: R Koosman; N Charlson
Original assignee: Individual
Current assignee: TRIPLEX ACQUISITION Corp A DE CORP
Priority date: 1973-05-03
Filing date: 1973-05-03
Publication date: 1974-09-03
Anticipated expiration: 1991-09-03

Abstract

An improved soil dewatering process and well drilling method which utilizes support equipment for a hollow core auger and a drive unit for the same which will permit drilling of a test hole, a well hole, and insertion of a well casing into the soil at a desired well depth for the purpose of lowering a water table or pumping water from the ground. The hollow auger is utilized to house the casing after the hole is initially drilled and a suitable plug in the end of the same is disposable and will be removed therefrom as the casing is inserted to insure that the auger may be backed out of the ground leaving the casing therein. The casing is sealed and incorporates its own screening in the form of slits therein which permits entrance of water into the casing so that a submersible pump and riser may be inserted into the same for pumping purposes. A quick disconnect coupling is incorporated into the method and apparatus to enable ready coupling of plural auger sections to obtain desired depth of well, the coupling providing a portion which will effect rotational thrust between sections and between the auger and the drive unit with a second portion overlapping the same and providing an axial coupling between parts to insure against separation of the same.

Description

United States Patent [191 Koosman et al.

[ APPARATUS AND PROCESS FOR SOIL DEWATERING [76] Inventors: Ronald L. Koosman, 7320 Minnetonka Blvd, St. Louis Park; Norman E. Charlson, Jr., 1020 50th Ave. NE, Minneapolis, both of Minn.

[22] Filed: May 3, 1973 211 A No.: 356,827

[52] US. Cl 175/57, 175/171, 175/323 [51] I'nt.- Cl E2lb 3/02 [58] Field of Search....; 175/57, 170, 171,323, 175/1; 166/63, 315

[56] References Cited UNITED STATES PATENTS 2,136,151 11/1938 Parrish 175/171 2,793,833 5/1957 Daniel, Sr. L. 175/1 2,890,861 6/1959 Cook 175/1 3,117,636 l/l964 Wilcox et aL... 175/171 3,190,377 6/1965 Rassieur 175/323 3,434,549 3/1969 Lowe 175/1 3,651,876 3/1972 Henson 175/323 Primary Examiner-James A. vLeppink Attorney, Agent, or FirmSchroeder Siegfried Ryan and Vidas [451 Sept. 3, 1974 [57] ABSTRACT An improved s oil dewatering process and well drilling method-which utilizes support equipment for a hollow core auger and a drive unit for the same which will permit drilling of a test hole, a well hole, and insertion of a well easing into the soil at a desired well depth for the purpose of lowering a water table or pumping water from the ground. The hollow auger is utilized to house the casing after the hole is initially drilled and a -.sections to obtain desired depth of well, the coupling providing a portion which will effect rotational thrust between sections and between the auger and the drive unit with a second portion overlapping the same and providing an axial coupling between parts to insure against separation of the same.

25 Claims, 7 Drawing Figures APPARATUS AND PROCESS FOR SOIL DEWATERING Our invention relates to soil dewatering and more particularly to an improved soil dewatering process, an improved method of well drilling for the same and improved apparatus for performing the drilling operation.

At the present time, soil dewatering or lowering of a water table is an accepted operation for various types of construction projects such as road building, setting of building footings, laying of sewer pipes of various types including gas and water mains and the like. Whenever the water table is at a level such as to interfere with normal construction procedures making digger or trenching dangerous in view of possible cave-ins or difficult from the standpoint of the presence of water in an area where excavation is to take place, it is conventional to dig or drill wells in the surrounding area or 3 along the line where construction is to take place and pump underground water to lower the water table below the construction level. At such a time, normal construction can take place and a subsequent return of water to the area will normally not adversely effect the construction positioned therein. Various methods of inserting well casings into well site area have been previously and are presently being employed. Among these include driving conventional well casing or drilling of the same, digging at a well site to a level so that a well casing may be inserted and inserting a well casing through a combination of digging and a water jetting process for lowering the casing. Generally, such present day processes require the use of added excavating and earth moving equipment, additional soil brought into the site area, and/or the use of additional water at a site area. The added equipment and the use of the same is exceedingly time consuming making present day drilling in dewatering operations exceedingly expensive.

In the present invention an improved soil dewatering process and well drilling method is provided by means of which, after the determination of a drill site by test boring, suitable portable equipment may be moved into position and an auger used to drill into the soil to the desired well level removing soil from the well hole through movement of the flights on the auger to move a minimum amount of soil thereby. Once the initial hole is drilled, similarly to loosen the soil, a hollow auger is inserted into the hole which auger has a removable plug in the end of the same. At this point, a conventional well casing or one preferably employing slits therein in place of screening to pennit the entrance of filtered water to the interior of the same is positioned with the auger. The casing is weighted at one extremity and when inserted into the interior of the auger and allowed, to drop or have a force supplied thereto at the end of the same will dislodge a removable plug at the end of the auger so that theauger may be removed from the drill hole and the casing retained therein. A suitable weight is added at the open end of the casing to hold it in position as the auger is withdrawn and soil or dirt is filled back into the hole near the casing a Ittqrea is libe sish s rem9y d a a ui abFpump and riser are inserted into the casing to perform a conventional pumping action with the casing sealed around the riser to create a vacuum in the system for more efiicient water removal. The removable plugs at the end of the auger is a disposable item remaining the drilled well hole and the weight sealed to the end of the casing prevents the introduction of dirt thereto. After suitable pumping to effectively lower the water table, the casing may be removed and used again.

In the apparatus for performing the improved process, a conventional boom type support mounting an auger drive unit with a special quick disconnect coupling between the end of the auger and the drive permits ready connection and disconnection of the drive unit with the auger member to facilitate the handling of the same and the introduction of the same into the soil. It further facilitates the handling and the moving of the casing to a position within the hollow auger to dislodge the plug in the bottom of the same. Similarly, the auger may be made in shorter sections for ease in handling and coupled together with the same quick disconnect coupling which will impart rotational thrust between the sections while connecting or coupling the sections of the auger as a whole together and to the drive unit axially to prevent separation of the same. During the drilling operation vertical force may be applied through the boom or drive unit to the auger to initially start or assist in urging the auger into the ground in the drilling operation. Under nonnal circumstances the additional force is required only for starting the drilling operation after which normal rotation of the auger and following motion of the boom in supporting the drive unit is required, The required time in effectively drilling and inserting casings is significantly reduced over prior methods in that no special earth handling equipment is required and a minimum amount of soil is removed from the ground during the drilling. The use of a hollow core auger with the inserted casing significantly decreases the amount of time required over prior method to effectively insert a well casing into a drill hole after boring of the same for effective dewatering operation.

It is therefore the principle object of this invention to provide an improved process for soiling dewatering.

Another object of this invention is to provide in an improved soil dewatering process an improved method for a drilling well.

A still further object of this invention is to provide an improved structure for well drilling.

A further object of this invention is to provide an improved apparatus for drilling a well for a soil dewatering operation in the form of a quick connectable and disconnectable hollow auger and appropriate drive structure for the same, together with an improved and simplified well casing.

A still further object of this invention is to provide an improved structure of this type and a process which will significantly reduce drilling time and reduce the cost of a soil dewatering operation.

Another object of this invention is to provide in an apparatus for well drilling operation, an improved and simplified disconnectable coupling between auger sections for effectively varying the length of the auger for varying well depths with the same coupling between the auger and the drive unit for effectively and quickly connecting and disconnecting the same.

These and other objects of this invention will become apparent from reading the attached description to- .gether with the drawings therein:

FIG. 1 is a schematic view of a boom mounted on a vehicle and supporting a winch and drive unit coupled to an auger for a well drilling or soil dewatering operation;

FIG. 2 is a fragmentary elevation view of an end of an auger showing a removable cutting head thereon;

FIG. 3 is a fragmentary elevation view of an end of an auger section showing a removable plug at the end of the same;

FIG. 4 is a perspective view of a coupling member adapted to couple a hollow auger section together as an integral unit or as to connect the auger itself to a drive unit;

FIG. 5 is a schematic view of a drilling auger in place with a well casing positioned therein and moved downwardly to dislodge an end plug positioned in the end of the drilling auger;

FIG. 6 is a schematic view of a well casing in place with an auger removed and elevated showing an additional step in the well drilling operation, and;

FIG. 7 is an elevation view of a well casing in position in a well hole and including a motor and riser sealed in the casing for a dewatering operation.

The invention in a soil dewatering system and a well drilling method incorporates apparatus peculiar to the same which will first be described such that the improved soil dewatering process will be more completely understood. As shown in FIG. 1, any type of portable or movable support, such as a track 10 or equivalent structure, may be utilized as a support for a boom 12 mounting a suitable winch l4 and auger drive unit 15 thereon. The boom may be oriented in several axes as displacement, such as the pivot axis 18, orienting the same on a turn table with a suitable hydraulic actuator 22 for elevating the same in a vertical plane. The turn table itself will be oriented on a truck in a conventional manner about a vertical axis to facilitate pick up and movement of auger parts, piping and associated equipment during the well drilling operation. The truck which may take varying forms, will normally incorporate Outriggers, such as is indicated at 25, to stabilize the base for the boom during the drilling operation and in terms of any lifting or turning of the boom structure in the handling of auger equipment or piping. As will be seen in FIG. 1, an auger indicated generally at will be employed, and more than one type of auger may be employed in the drilling operation, that is solid core and/or hollow core augers. In addition, the auger may be formed of a plurality of sections, such as is indicated at 31 and 32, or may be a single solid length unit. The auger employs a cutting head, such as is indicated at 35, with cutting teeth 36 about the base of the same, the cutting head being solid connected to the end of the auger section or frictional connected and readily removable depending upon the construction of the same. Thus, the cutting head may be frictionally mounted externally so that it may be removed or may be mechanically pinned as the case may be. As indicated in FIG. 2, the auger during certain portions of the drilling operation may employ a removable plug 40 preferably of plastic material which will be frictionally held in the end of the same to close the auger during a certain portion of the drilling operation.

As a portion of the apparatus used in the improved soil dewatering and well drilling process, a quick disconnect coupling is employed to facilitate interchange of the auger parts or to remove the drive unit from the auger 30. Thus, in FIG. 4, a drive shaft having a suitable flange plate 46 secured thereto will be fitted into the drive coupling or shaft of the drive unit 15 and pinned thereto in driving relationship therewith. The plate 46 will mount one part of the disconnect coupling, indicated generally at 50, which is formed of collar parts to be hereinafter described. The first collar or member is shown at 55 as incorporating rectangular recesses 56, and flanges 57 along one edge of the same, the collar being secured to one end of the auger section clear of the fiighting 60 thereon. The collar 55 is suitably welded or secured to the auger part and a recessed surface or grooved surface 58 is positioned behind the same or on the oppoite edge of the collar from the flanges and recesses 56, 57, or lands. The cooperating collar part or portion of the coupling as shown in FIG. 4 is attached to the plate 46 and incorporates an outer cylindrical collar 62 member or second collar having a plurality of flange members 65 distributed about the outer peripheral surface of the same and extending beyond one edge of the collar. Positioned within the second collar 62, is an inner collar member, indicated at 65, having lands or flanges 66 and grooves or recesses 67 therein. This inner collar member is of the same diametrical dimension as the first collar member 55 and the flanges and grooves are of the same size as the flanges and grooves or

recesses

56, 57, in the collar member 55 so that the same may fit therein in a rotational thrust imparting or splined type of connection. This inner collar member is suitably welded to the outer collar 62 whose diametrical dimension is such that its internal dimension will fit over and telescope over the first collar member 55. With the proper axial orientation, the inner collar member 65 and the first collar member 55 will butt in a splined or mating relationship with the outer collar 62 overlying the same. The flanges 65 are formed or spaced parallel plates which are suitably welded in pairs about the peripheral surface to the outer surface of the collar members 62 at spaced points around the periphery of the same, such as four sets of flange members positioned on the outer surface thereof. These plates form the housing and support structure for cam members, indicated generally at 70, which cam members are formed of a lever portion or handle portion 71 and an eccentric portion 72 which eccentric portion is pivoted on the pairs of plates forming the flanges 65 through pivot pins indicated at 74. This location of pivot will be beyond the lower edge of the collar members 72 so as to be enclosed therein. The cam surface is eccentric of the pivot, and the handle portion 71 is thus pivoted between the plates forming the flange members 65 so as to position the eccentric portion radially inward toward the axial center of the collar member. Suitable pin holes or locks 76 are located in the handle portions and similar apertures 77 are provided in the flange plates so that a suitable pin means may secure the handles therein with the cam members pivoted to an eccentric position. When the parts of the coupling are telescopically coupled together and the inner collar member 65 is aligned and mating with the first collar member 55 on the cooperating auger section, the eccentric portion will rest on the grooved surface 58 to one side of or common with the first collar member 55 remote from the flanges and recesses. This will provide a force urging the first collar member 55 against the inner collar member 65 and with the collar 62 to prevent axial separation of the parts. The nesting or splining of the flanges or recesses between the collar member 55 and the inner collar member 65 will provide a thrust surface between the plate 46 and the auger 30 to impart rotational thrust from the drive shaft 45 to the auger section 31 to drive the same from the motor 15. Four such sets of recesses and flanges are distributed about the peripheral surface to provide the drive coupling which is readily connectable and disconnectable by releasing the pins holding the cam members in position on the flanges 65 permitting the same to be rotated free and allow axial separation of the parts.

While we have shown the coupling in connection with the drive shaft 45 of the drive motor or the shaft 45 adapted to be coupled thereto permanently, it will be understood that these coupling parts will also be applied between the

auger sections

31, 32. The

coupling parts

65 and 62 may be attached to the end of the auger section with a collar member 55 attached to adjacent end of the next auger section 32 for the purpose of combining auger sections in the same manner. Thus,

as will be hereinafter noted when it is necessary to drill a well hole deeper than the length of a given auger section, additional sections may be connected together to form the composite hollow auger, such as is indicated at 30, formed by the

sections

31, 32, in FIG. 1 for added length or depth of the well hole. The particular coupling described in FIG. 4 is a preferred form of the disconnectable coupling, but it will be recognized that other types of disconnectable coupling may be employed within the broad teaching of the soil dewatering process.

In addition to the drilling equipment, the improved soil dewatering process or well drilling process employs a casing, indicated generally at 80, which in its preferable form is a hollow plastic tube. This casing will be of a unitary structure having a length commensurate with the depth of well to be drilled and will incorporate screening or entrance passages into the lower end of the same, such as is indicated by the slits 85, which are machined through the wall of the casing and distributed along the lower portion of the same to provide an integral screening effect and passage to the interior of the casing. Preferably for normal sand or soil conditions these slots or slits will be machined in by metal with a width dimension of approximately 0.048 inches in width and of a length in the vicinity of 2 to 3 inches to provide a water passage from the exterior to the interior of the casing with the width being such that particulates, such as sand or the like, will be prevented from entering the interior of the casing. These slits will be distributed circumferencially around the lower portion of the casing and will be distributed along the length of the same or horizontally as indicated in FIG. 7, to provide an integral screening with the casing itself. The size of the slits may be varied for various soil conditions. As shown in FIG. 7, the casing will have applied thereto a suitable plug 88, preferably of concrete, in the lower extremity of the same which will seal the lower extremity of the casing to prevent water and sand or dirt from entering into the casing at this point. As it will be hereinafter noted, this extremity will be positioned within the auger in the installation of the well casing and the weighted end will also be used to remove the removable end cap or plug 40 from the end of the auger in the process as it will be hereinafter described.

In the improved soil dewatering process, which incorsteps will encompass the boring of a test hole into the soil with a soil testing vehicle to determine the depth of a a proposed well. Thus, in the construction operation,

porates the improved method of well drilling, the initial and where soil dewatering is required prior to the ac tual excavation, a series of test holes will be bored along the particular path or at a particular construction site to determine water content of the soil or the water table to locate proposed wells for the purpose of removing the water or lowering the water table. The equipment involved may be a separate soil testing vehicle with a water hole drill which would sample the soil and would determine the height of the water table and hence the height or depth of the proposed well. For the purposes of the present disclosure, apparatus such as shown in FIG. 1 may be utilized to accomplish this step in that a hollow or solid core auger could be utilized for this purpose. Once the proposed site for a wellis located, it would be staked to indicate a desired drilling depth and equipment of the type shown in FIG. 1 could be brought to the sites for the actual drilling of the Well, should a separate soil testing vehicle be used. The truck, indicated at 10, may take varying forms but would normally have a power take-off and a separate hydraulic power supply for the purpose of operating the actuators associated with the turn table, the boom, the drive motor for the auger and winch. Similarly, the support bed for the boom would normally employ actuators for operating the outrigger jacks 25 which when the actual drilling operation takes place will be set to stabilize the vehicle. Operation of the engine power supply on the vehicle would provide the motive power for the hydraulic system (not shown) or a separate gasoline engine may be employed, both of which are conventional with equipment of this type. Normally, the boom is stored for transportation purposes and this would be positioned in anoperating position and the winch line 14 used for removing auger sections from the stored location on the truck or accompanying vehicle and placed on the ground. Where a single section is used for the initial drilling, only the initial section, such as is indicated at 32 would be connected to the drive unit. The drive unit is pivotally mounted on the boom by means of a special mounting arm in a conventional manner so that it can be coupled to the auger when the same is lying flaton the ground by tilting of the boom to the ground and positioning the drive head adjacent to the same. The coupling employed between drive unit 15 and the auger section 2 is that shown in FIG. 4 and as previously defined would couple the drive shaft 45 and plate 46, through the

collar member

65, and 62 to the collar member 55 on the end of the auger section with the lever member being pivoted to lock the same against axial separation.

Initially, a hole may be drilled at the well site as determined by the test hole boring with an auger section which may or may not be hollow to loosen the soil.

Thus a solid core auger may be utilized for the initial digging or a hollow core may be utilized for the same. Initially a cutter head 35 would be incorporated on the digging end of the auger and this would normally be pinned thereto but could be held frictionally thereon. Depending upon the depth of the proposed well, one or more auger sections may be connected to reach the desired depth. Thus, as additional sections are needed beyond the initial section, the additional sections will be coupled by effecting a disconnect of the driving head 15 and the auger section in the ground, the connection of an additional section to the driving head and the coupling of the added section to that already in the ground through a coupler, such as is indicated in FIG. 4 in the coupling process. Digging will be effected by rotational input to the auger 30 from the drive unit 15. In the initial penetration of the ground, force may be applied by vertically displacing the boom 12 carrying the auger drive head through its displacement actuator 22 to apply a downward thrust in addition to the rotational thrst in the augers to permit it to easily dig into the ground. Thereafter the actuator 22 will displace the boom only to the degree that it follow the auger into the ground as the same is rotated. As the auger is rotated the flights 60 thereof will bring up spoil or soil from the drill hole, depositing the same on the surface around the periphery of the hole. With this type of digging,-a minimum of soil is removed from the ground. While in the initial digging of the hole, it is desirable to provide a cap on the end of the auger or a cutter head for more efficient drilling. However, it is possible that an unplugged hollow auger may be utilized allowing spoil to enter the interior of the same which would be later removed after the auger is withdrawn as will be hereinafter defined. Thus, as shown in FIGS. 1, 2, and 3, the initial hole will be dug or drilled into the ground to the desired depth through apparatus and equipment as previously described and in the manner previously described. When the desired depth is reached, the auger head or digger head is reversed and the auger is screwed out of the hole to remove as little spoil as possible from the hole. Should a cutter head not have been used in the initial drilling operation, at this point as the boom is elevated and with the auger withdrawn from the bore hole, the auger will be rapped or jarred to dislodge and remove the spoil or soil within the interior of the same. Should a cutting head 35 have been attached thereto, it will be removed at this point and a solid plastic disposable plug will be frictionally inserted in the digging end of the same. The plastic plug when inserted into the bottom of the hollow auger stem prevents the entrance of sand and water into the interior of the hollow auger and the next step of operation permits disposal of the plug piece as will be hereinafter described.

With the plastic plug 40 preferably inserted into the cutting end of the auger, after the same has been withdrawn from the drilled hole, the auger can be then resinserted into the original hole and rotated until the desired depth of the well is reached. lt is normally not necessary to uncouple the auger sections with these steps since the boom 12 is such length as to suspend the auger for this purpose. However, if it is not, than the individual sections would be removed as the auger is withdrawn and reinserted in the manner with the quick disconnect coupling effecting the rotational and axial coupling of the sections. Once the auger is back into the original hole and at a desired depth, the digger is disconnected from the auger 30. At this point, the boom is rotated to the location of the well casing or plastic tubing 80 and the winch is used to pick the same up and suspend it with its sealed end down so that it will be inserted into the auger casing and lowered such that the casing with its concrete plug would be inserted into the hollow auger shaft to a position of about feetabove the installed height. The purpose for the step of initially drilling the hole and removing the auger to replace the'cutting head is for the purpose of installing the casing within the hollow auger and positioned in the ground so that the casing may be left therein as the auger is withdrawn. Where the cutting head itself is disposable and frictionally held thereon, the step of removing the auger and replacing the cutting head with a removable plug can be eliminated and the casing may be installed after the initial drilling. Once the casing is in position in the hollow auger shaft and lowered to a position slightly above its installed depth or height, the winch line is loosened permitting the casing to drop knocking out the plastic cap or plug from the bottom of the hollow auger tube. The plug 40 being disposable will remain in the ground and be positioned below the end of the auger as indicated in FIG. 5. The length of the casing 80 will be less than the length of the auger so that it may effectively be dropped within the auger to dislodge the plug. Where additional force is required a heavy weight such as a tubular metal member may be suspended by the winch into position over the end of the casing 80 and allowed to drive the plug out of the end of the auger. This weight will remain in the end of the casing for the purpose of holding the same down into the ground as the auger is removed. A special tooling may also be utilized for rapping the end of the casing to dislodge the plug in place of the weight. The heavy weight 100 is inserted primarily to prevent the casing from floating as the auger is removed. Thus in FlG. 6 the end of the auger 30 is shown connected to the digger or drive unit 15 and the drive unit is rotated or reversed to screw the auger back out of the ground, leaving the casing 80 therein. Before the auger is completely removed, a check will be made to insure that the plug has been removed and the casing is in the ground. If it is not, the special tool may be attached to the end of the boom and engage the casing to insure that this takes place. As the auger is rotated in the reverse direction, the boom 12 is elevated to a position to where it will clear the end of the casing at which point the auger will be brought to the ground away from the well site casing and disconnected from the digger or drive unit 15. The individual auger sections may be similarly disconnected, should more than one section be employed. The winch 14 is used to remove the weight 100 from the end of the casing as the dirt or spoil around the drill hole is allowed to fall into the hole and shoveled back into the hole surrounding the casing to hold the cating into position. The auger sections are then stored on to the truck or whatever mode of transporation is utilized for transporting the same since they are no longer to be used in the drilling operation. The spoil as it is shoveled back into the casing requires a minimjm amount of restoration around the drill hole and the drilling operation is completed at this point. At this time a check will be made to insure proper drainage of water from the ground, as indicated at in FIG. 7 and to insure that the screening 85 below the water table, as indicated by the dotted line 130, is unplugged so that the drainage of the water from the surrounding ground into the interior of the casing is being effected.

Under certain soil conditions it may be desirable to insert an external filter outside of the casing 80 to improve drainage into the area the well. For example, when soil conditions are essentially clay or other material preventing effective drainage along the extent of the casing from the top of the water table to the area of the screening, it may be desirable to improve drainage by inserting into the well hole around the casing filter material, such as aggregate which is devoid of fines or silt, to improve drainage. With the improved drilling process, it is possible to introduce such filter material into the auger and around the casing prior to removal of the auger from around the same or before it is withdrawn. The amount of filter material which can be introduced under such condition will be controlled by selecting the relative difference between the internal dimension of the anger as compared with the external dimension of the casing. Thus in FIG. 7 is shown a layer of aggregate or filter material 140 around the casing which will extend the lower end of the well casing to some point about the water table as a filter layer for the well under certain soil conditions. The thickness of the layer can, be controlled by sizing of the auger and casing and the introduction of the same will be under conditions where little or no silt will be exposed to the casing screening or slots to plug the same. This step will be based only where subterranean soil conditions dictate such usage for improved drainage conditions.

The drilling operation being completed, the boom may be stored and the Outriggers raised with the power supply to the motor equipment on the boom cut-off. Assuming that the well is satisfactory, a temporary portable pumping equipment may be employed to remove water and sand initially from the casing to insure that it is suitable for proper pumping. That is, good for the soil dewatering purposes. Should it not be, the procedure must berepeated with the new casing or with the casing previously installed, removed and a new drill site obtained. Assuming that the well is good at this particular point, and it is desired to start pumping, a suitable sumersible pump, such as is indicated at 150 with a riser 160 is inserted into the casing 80 and a plug member 170 is positioned in the upper exposed end of the casing which is above the ground level to effectively seal the casing at the riser. A pumping operation can then begin and the plug 170 in the end of the casing will create a vacuum assisting the pump in removing the water from the interior of the casing and effecting a lowering of the water table in the soil dewatering operation. Water pumped from the well casing may be disposed of in a conventional manner by allowing the same to be disposed of on the surface in a nearby-location but sufficiently removed as to present no hindrance to the subsequent excavation which will thereafter take place. When the water table is lowered to the desired depth, ditching or excavation may take place. In a soil dewatering operation, it is expected that a series of such wells will be installed, as in the case of sewer lines along the proposed route and the water table efiectively lowered along the same before excavation takes place. Once the water table is lowered to a sufficient depth, the excavation can take place since the soil dewatering process is completed until continued drainage required that the pump continue operation during excavation and installation. Thus installa tion can be effected under conditions where water content of the soil in the digging or dredging area will not present a hazard. At this point, the pumps will be removed and the well casings recovered by removal of the same from the ground for re-use at a later time and site.

The improved soil dewatering process employs an improved well drilling process by means of which a minimum amount of digging and/or soil restoration is required before and after the well drilling operation. It

incorporates a simplified apparatus in the terms of the auger sections, preferably hollow which are supported by a boom structure and driven by a rotatable drive unit or digger mounted on the boom and connected to the auger sections through quick disconnect type couplings. The improved structure enables a significant reduction in overall drilling time over present well drilling steps with an appropriate overall reduction in costs because of time saving. In the well drilling operation,

the hollow auger is used to house the casing after the hole has been drilled and before the auger is removed. A removable plug or disposable cutter head is utilized in the end of the auger to insure that the dirst and water will not fill the end of the auger as the casing is inserted. This cutting head and/or plug is disposable and is left in the ground after being removed from the end of the auger as the casing is installed. The casing itself is sealed at one extremity and incorporates screening formed integral therewith through the use of a series of horizontal slots of very fine width such as to prevent the entrance of sand and dirt into the interior of the casing as the water is filtered into the same. The casing after usage is recoverable and reusable and once the well is installed and a submersible pump or surface pump with riser may be utilized for pumping and subterranean area as defined by the well depth for effecting the reduction of the well table for construction purposes. The dewatering holes or wells of this type may be effectively drilled up to a foot depth with apparatus of this type in relative short periods of time effecting an overall reduction of dewatering costs for construction purposes.

Therefore, in considering this invention it should be remembered that the present disclosure is illustrative only and the scope of the invention should be determined by the appended claims.

What is claimed is:

l. A process for soil dewatering which includes the steps of:

a. Boring a test hole at a proposed site to determine the depth of a proposed well;

b. Positioning drilling equipment adjacent the test hole site and drilling a well hole with an auger to the desired depth to loosen the soil;

c. Removing the auger from the hole and positioning a removable cap at the bottom end of a hollow auger to prevent sand and water from entering into the confines of the hollow auger;

d. Replacing the auger in the well hole and rotating the same until the desired depth is reached;

e. Inserting a well casing with a screening therein into the hollow auger and positioning the casing into the extent of the auger with sufficient force to dislodge the removable cap at the bottom end of the hollow auger;

f. Holding the casing into position and removing the auger from the drilled hole leaving the well casing and the cap therein;

g. Filling the hole around the casing to secure the casing therein;

h. Inserting a riser and screen with a pump attached thereto into the casing to remove water as it flows into the casing;

i. And, operating the pump to drain water from the casing as it flows into the same through its screen.

2. The process of claim 1 and including an additional step of adding additional auger sections to the auger during the initial and secondary drilling steps to reach the desired depth of the well.

3. The process of claim 2 and including the additional step of adding the weight to the upper end of the well casing after it has been inserted into the hollow auger to hold the casing in place as the auger is removed.

4. The process of claim 3 and including the step of removing the added weight in the open hollow end of the well casing after the auger has been removed from the well site and the filling around the casing in the drill hole to secure the casing therein.

5. The process of claim 1 in which the step of applying force to dislodge the removable cap from the bottom of the auger includes the step of allowing the well casing to be dropped within the hollow auger from a position above the lower end of the same to remove the cap from the bottom of the auger.

6. The process of claim 1 and including the step of sealing the riser to the casing after insertion of riser and well screen in the casing to create a partial vacuum within the well casing and system removing the water therefrom. v

7. The process of claim 6 and including the additional step of removing the casing from the ground when the water table in the soil has been lowered to the depth of the casing.

8. The process of claim 1 in which the step of positioning the drilling equipment at a test hole and drilling the well hole with a hollow auger to the desired depth includes the step of applying initial downward force to the auger to effect the drilling.

9. The process of claim 1 in which the step holding the casing and removing the auger after dislodge of the removable cap proceeded by the step of introducing filter material within the auger and around the casing so that it will line at least a portion of the well hole around the casing from the desired depth to a point at or near the top of the water table.

10. A process for drilling a well for lowering the level of underground water which includes the steps of:

a. Positioning the drilling equipment at the test hole site and drilling a well hole with a hollow auger to the desired depth;

b. Removing the auger from the hole and positioning a removable cap at the bottom end of the hollow auger to prevent earth and water from entering into the confines of the hollow auger;

c. Replacing the auger in the original hole and rotating the same until the desired depth is reached;

(1. Inserting a well casing with a screen therein into the hollow auger and positioning the casing into the extent of the auger with sufficient force to dislodge the removable cap at the bottom end of the auger;

e. Holding the casing in position by applying a weight to the upper end of the same and removing the auger from the drill hole leaving the well casing and the cap therein; and

f. Filling the hole around the casing to secure the casing therein.

11. The process of drilling a well of claim 10 in which the step of positioning the drilling equipment at a test hole and drilling the well hole with a hollow auger to the desired depth includes the step of applying initial downward force to the auger to effect the drilling.

12. The process of drilling a well of claim 11 and including a step of adding additional auger sections to the auger during initial and secondary drilling steps to reach a desired depth well.

13. The process of drilling a well of claim 10 and including the step of removing the addedweight from the hollow open end of the well casing after the auger is removed from the hole and after the filling of the hole around the casing to secure the casing therein.

14. The process of drilling a well of claim 10 in which the step of applying force to dislodge the removable cap from the bottom of the auger includes the step of allowing the well casing to be dropped within the hollow auger from a position above the lower end of the same to remove the cap from the bottom of the auger.

15. The process of drilling a well of claim 10 in which inserting the well casing with the screened end of the hollow auger includes positioning the well casing with a weighted enclosed extremity first into the hollow auger and with the screen slits cut therein and positioning the closed and screen slit end of the well casing in the lower most portion of the auger with sufiicient force to dislodge the cap at the bottom end of the auger.

16. The process of drilling a well of claim 10 in which the steps for drilling a well are proceeded by the boring of a test hole at a proposed well site to determine the depth of a proposed well.

17. The process of drilling a well of claim 9 and including the step of adding additional filter material to the interior of the auger and around the casing before removal of the auger from around the same.

18. A process of sinking a well casing consisting of:

a. Drilling a well hole to a depth substantially below the existing level of underground water with a hollow auger having a removable member extending across its lower end;

b. Inserting a well casing having screen means in the lower end portions thereof into the hollow auger and forcing the casing downwardly with sufficient force to dislodge the removable member from the auger and to extend to a position within the lower portions of the well hole;

c. Removing the auger from the well hole while holding the casing in said position, and;

d. Securing the casing in said position.

19. A process for sinking a well casing consisting of:

a. Drilling a well hole with an auger to a depth substantially below the existing level of underground water;

b. Removing the auger from the hole and applying a removable cap to the lower end of a hollow auger to preclude earth from entering the hollow confines of the auger during subsequent drilling operatrons;

c. Placing the hollow auger within the well hole and rotating the same until the desired depth is reached;

d. Inserting a well casing having screen means in the lower end portions thereof into the hollow auger and forcing the casing downwardly with sufficient force to dislodge the removable cap from the auger and to extend to a position within the lower portions of the well hole;

e. Removing the auger from the well hole while holding the casing in said position; and,

f. Securing the casing in said position.

20. Apparatus for drilling a well comprising, a support structure having a drive unit and a power supply therefore positioned thereon, a hollow auger member adapted to be connected to the drive unit, quick disconnect means coupling the auger member at one extremity to said drive unit, friction type removable closure means closing the hollow auger at the other extremity, said quick disconnect means including cooperating portions the first of which is formed by a collar having rectangular notches and flanges distributed on one edge of the same, and a second portion including a second collar adapted to telescope over the first named collar and including an inner collar member with notches and flanges there adapted to fit into and mate with the notches and flanges of the first named collar, and releasable means for holding the second collar in telescopic relationship with the first collar and the inner collar member in mating relationship with the first collar.

21. The apparatus for drilling a well of claim 18 in which the releasable holding means includes a plurality of flange means positioned on the outer peripheral surface of the second collar and mounting eccentric cam members pivotally therein with handle means connected thereto, said flange means with the cam members overlying the first collar such that the cam members fit behind and bear against the first collar holding the same against the inner collar member whenever the second collar and the first collar are fitted in telescopic relationship and the handle means are pivoted to pivot the cam members.

22. The apparatus of drilling a well of claim 21 in which the cam members with the handle means thereon are lever members with cam surfaces eccentric with an axis of pivot mounting the lever members in the extremity of the flange means remote from the second collar such that upon pivot of the lever members the eccentric cam surfaces are displaced radially in the direction of the axis of the hollow auger.

23. The apparatus for drilling a well of claim 22 in which one of the first and second collars is carried by the drive unit and the other of the collars is carried by the auger with the collars being suitably welded respectively thereto.

24. The apparatus for drilling a well of claim 23 in which the first collar secured selectively to the drive unit and an extremity of the hollow auger has associated therewith a grooved surface behind the collar and remote from the recesses and flanges therein which is adapted to receive the eccentric surfaces of the cam members when the levers are pivoted to lock the portions of the coupling in mating relationship and against axial separation.

25. The apparatus for drilling a well of claim 24 in which the auger member is formed of a plurality of auger sections with one of the auger sections carrying one of the first andsecond collars and the extremity of the adjacent auger section to which it is to be coupled carrying the other of the collar members to secure the auger sections in thrust imparting relationship and against axial separation.

Claims

1. A process for soil dewatering which includes the steps of: a. Byoring a test hole at a proposed site to determine the depth of a proposed well; b. Positioning drilling equipment adjacent the test hole site and drilling a well hole with an auger to the desired depth to loosen the soil; c. Removing the auger from the hole and positioning a removable cap at the bottom end of a hollow auger to prevent sand and water from entering into the confines of the hollow auger; d. Replacing the auger in the well hole and rotating the same until the desired depth is reached; e. Inserting a well casing with a screening therein into the hollow auger and positioning the casing into the extent of the auger with sufficient force to dislodge the removable cap at the bottom end of the hollow auger; f. Holding the casing into position and removing the auger from the drilled hole leaving the well casing and the cap therein; g. Filling the hole around the casing to secure the casing therein; h. Inserting a riser and screen with a pump attached thereto into the casing to remove water as it flows into the casing; i. And, operating the pump to drain water from the casing as it flows into the same through its screen.

6. The process of claim 1 and including the step of sealing the riser to the casing after insertion of riser and well screen in the casing to create a partial vacuum within the well casing and system removing the water therefrom.

10. A process for drilling a well for lowering the level of underground water which includes the steps of: a. Positioning the drilling equipment at the test hole site and drilling a well hole with a hollow auger to the desired depth; b. Removing the auger from the hole and positioning a removable cap at the bottom end of the hollow auger to prevent earth and water from entering into the confines of the hollow auger; c. Replacing the auger in the original hole and rotating the same until the desired depth is reached; d. Inserting a well casing with a screen therein into the hollow auger and positioning the casing into the extent of the auger with sufficient force to dislodge the removable cap at the bottom end of the auger; e. Holding the casing in position by applying a weight to the uppeR end of the same and removing the auger from the drill hole leaving the well casing and the cap therein; and f. Filling the hole around the casing to secure the casing therein.

13. The process of drilling a well of claim 10 and including the step of removing the added weight from the hollow open end of the well casing after the auger is removed from the hole and after the filling of the hole around the casing to secure the casing therein.

15. The process of drilling a well of claim 10 in which inserting the well casing with the screened end of the hollow auger includes positioning the well casing with a weighted enclosed extremity first into the hollow auger and with the screen slits cut therein and positioning the closed and screen slit end of the well casing in the lower most portion of the auger with sufficient force to dislodge the cap at the bottom end of the auger.

18. A process of sinking a well casing consisting of: a. Drilling a well hole to a depth substantially below the existing level of underground water with a hollow auger having a removable member extending across its lower end; b. Inserting a well casing having screen means in the lower end portions thereof into the hollow auger and forcing the casing downwardly with sufficient force to dislodge the removable member from the auger and to extend to a position within the lower portions of the well hole; c. Removing the auger from the well hole while holding the casing in said position, and; d. Securing the casing in said position.

19. A process for sinking a well casing consisting of: a. Drilling a well hole with an auger to a depth substantially below the existing level of underground water; b. Removing the auger from the hole and applying a removable cap to the lower end of a hollow auger to preclude earth from entering the hollow confines of the auger during subsequent drilling operations; c. Placing the hollow auger within the well hole and rotating the same until the desired depth is reached; d. Inserting a well casing having screen means in the lower end portions thereof into the hollow auger and forcing the casing downwardly with sufficient force to dislodge the removable cap from the auger and to extend to a position within the lower portions of the well hole; e. Removing the auger from the well hole while holding the casing in said position; and, f. Securing the casing in said position.

25. The apparatus for drilling a well of claim 24 in which the auger member is formed of a plurality of auger sections with one of the auger sections carrying one of the first and second collars and the extremity of the adjacent auger section to which it is to be coupled carrying the other of the collar members to secure the auger sections in thrust imparting relationship and against axial separation.