JPH0378480B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is primarily intended for use in the extraction or enhanced extraction of oil from petroleum-containing geological formations, or for the extraction of mineral deposits or the like, or for other purposes. The aim is to create a surface drilling system for penetrating underground layers. The system includes an assembly with a piston arrangement within a guide device.
The piston device consists of a body formed by a drilling tube which is open at its rear end and includes a hydraulic jet-type drill head at its forward end, into which a plurality of fluid outflows are provided. A port is provided. The guide device is a tube or pipe that is in fluid communication with the perforated pipe. There is a sealing device between the perforation tube and the guide pipe, so that the fluid under pressure flowing through the guide tube and the perforation tube exerts a force that causes the piston device to move forward through the tube bending device. direction and placed into the geological formations beneath the earth's surface.

In a preferred embodiment, the tube bending device is referred to as a "whipstock" and is attached to a guide pipe that causes the piston body or perforated tube to change direction from a vertical direction to a generally horizontal direction at a short radius. It will be done. The size of the radius is, for example, the outer diameter is 1 1/4 to 1
Sizes are on the order of 6 inches to 12 inches for 1/2 inch, wall thickness 0.080 to 0.125 inch steel drilled tubes. In such normally rigid metal piston bodies, collapse of the tube during changes in direction occurs due to hoop stresses caused by the internal high-pressure drilling mud and bending stresses as it travels through the whipstock. Or plastic deformation occurs in the metal without fracture. Thereafter, the tube is kept almost straight by a straightening device.

The handle of the whip can be stationary or retractable. The retractable whipstock consists of two connected assemblies that, when extended from a retracted position within the structure, provide a guideway for bending the arcuate tube. When fluid pressure is applied to the guide pipe, the guide pipe exerts a force on the perforation tube and the perforation tube is propelled downwardly through the guide pipe and through the guide passage, which causes the tube to bend and the perforation head to Projected laterally relative to the strata. Each whipstock assembly has a series of rollers or sheaves rotatably supported by the whipstock to form a section of an arcuate guideway.
The tube bending device also includes a device for straightening the tube as it exits the guideway.

Two or more assemblies for injection of hot fluids, such as steam, to heat oil in the formation or to flow oil to nearby production wells or to production pumps located within the same well casing. Alternatively, it may be provided within a well to provide two or more laterally extending circular holes.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a system and method for forming radially extending circular holes (radials) with relatively short radius turns, and which is efficient and economical compared to conventional systems and methods. It is to be.

It is a particular object of the present invention to form multiple radial sections within a single pre-existing well casing.

It is yet another object of the invention to provide several radial systems within a combined injection production well.

It is a further object of the invention to provide a system of the type described above which is capable of drilling into unhardened formations without the need to use a rotating drill head.

Further objects and features of the invention will become apparent from the following description with reference to the accompanying drawings.

In one primary use of the invention, a system is provided for forming one or more pipes or tubes in a radial hole extending from a pre-existing cased well. The primary use of such radial pipes is to inject hot fluids, such as steam or solvents, into the surrounding formations to make the highly viscous oil in the underground formations more fluid. It is to be. An important use is to heat the oil remaining in the ground by producing wells that are no longer producing economically.

Referring to FIG. 1, a surface 20 above an underground mineral deposit 22 is illustrated, upon which a production rig is placed on the right and a coiled tube rig 26 is placed on the left. The production rig 24 features one or more guide tubes or guide pipes 3.
0 and 32 are screwed together in the field in a conventional manner. Piston body or perforated tube 34
is formed of a solid-walled metal tube, for example having an outside diameter of about 1.25 inches, which is wound over the coil spool 26 and downwardly into the guide pipe. Once a sufficient length of the piston body or bore tube 34 has entered the guide pipe to reach the desired final radial length, the bore tube is cut and lowered into the guide pipe.

The lower part of the figure shows the well casing 28 filled with pre-existing cement. Casing 2
Included within 8 are two different axially oriented guide pipe arrangements, the guide pipes comprising axially oriented guide tubes or guide pipes 30 and 32, which pipes are Each ends in whipstocks 30a and 32a, each having a respective curved body or guideway. The piston devices are each placed within a guide pipe, each piston device including an elongated piston body in the form of a drilling tube, the tube terminating in a drill head device. The piston body is made of a relatively rigid metallic material, such as steel, and thus has the advantage of following a nearly straight passage through the formation. As shown, only the piston body or drilling tube 34 extends within the guide pipe 30 and is visible by the drill head 36 at its forward end. A suitable guide pipe has an outside diameter of about 2 inches and is sectioned into 30 foot lengths.

The piston body or bore tube 34 is deflected by bending and, by bending and drilling into the formation as it passes through the whipstock 30a, injects hot fluid, such as steam, into the formation to increase the viscosity. A radial or transverse tube suitable for injection to heat and extract certain oils. Alternatively, heat from the hot fluid causes the oil to flow toward and back into the casing, which includes the production pump and radial section, better illustrated in FIGS. 7 and 8, discussed below.

In the illustrated embodiment, a fluid downcomer 38 (e.g., 1.25 inch outside diameter) connects guide tubes 30 and 32.
A foamed or foamy or highly viscous fluid protrudes from the center of the drill head 36 to assist in removing chips formed during operation of the drill head 36 or later when pouring cement. Such chips flow back along the tube 34 and are picked up by the bubbles and flow upwardly through the axial space within the well casing 28. tube 3
8 is also used to convey and pour cement into chamber 40 to secure the radial section and whipstock location after the vertical circular hole drilling is completed.

In typical operations, well casing 28 may be present from the time of the prefabricated injection well. A typical size for such a casing in the United States is 5 1/2 inches. Typically, the casing is ground and the lower layer is reamed in the usual manner to form a void 40 in which the whipstock 30a is placed. In one alternative method, an abrasive material, such as silica, is added to the drilling fluid supplied to the drill head 36 or another drilling device, which is directed against the existing well casing wall or cement layer, so that The perforation tube 34 and head 36 extend through the wall or cement layer to form a radial section.

The general principles of forming radial sections in accordance with the present invention have been described. However, a more detailed structure of the parts will be explained below with further reference to the drawings. Briefly, the piston body or tube 34 is adapted to move within the guide tube and provides an internal fluid passageway with an outer open rear end and a drill head arrangement at the forward end. A single or several fluid outlet ports are provided for passage of drilling fluid from the fluid passageway in the piston body into the nearby formation. The interior of the guide pipe arrangement is in fluid communication with the aft end of the passage within the piston body. A sealing device provides a seal between the piston device and the guide tube. High pressure fluid through the piston body fluid passage applies pressure to the rear of the drill head assembly, causing the piston to move in a forward direction. When the piston body or tube reaches the whipstock, the combined stress is the hoop stress (radial stress) caused by the high pressure fluid within the piston body.
The piston body or tube, which is usually a rigid metal, is subjected to stress along with bending stresses in the whip handle, causing it to be plastically deformed in a physical metallurgical sense and bending radially so that it can move within the formation. In a preferred case, the direction is changed horizontally. The high pressure fluid exiting the drill head penetrates the formation and produces chips that are reduced to a slurry and travel rearwardly along the outer periphery of the piston body and into the cavity 40. Foam or other collected liquid flowing downward through the downcomer pipe 38 is now added to the slurry to maintain the axial void in the casing - which would otherwise be occupied by the guide tube if the slurry were not flowing. It is lifted to the surface of the stratum through. In another case, not shown, a fluid downcomer is not required and the fluid is directed into the surrounding formation under such force,
Fractures in the formation create fissures in which the slurry formed flows, so that few, if any, chips are moved backwards along the radial section, thus collecting the chips on the ground. That is not required.

A significant advantage of this system is that it allows radial holes to be drilled with a non-rotating drill head and that the drilled hole is cased during drilling.

Referring to FIG. 2, a vertical hydraulic jet perforation system is illustrated. This system utilizes the piston guide pipe assembly of FIG. 1 in which the piston tube changes direction from horizontal to vertical on the surface by passage through whipstocks on the surface. This allows the guide pipe to extend along the ground rather than being supported vertically. The subsurface formation 42 includes an upper void 44 to facilitate drilling. Guide tube 46 is supported at the ground surface in a conventional manner. The rear end of guide pipe 46 is shown projecting into housing 48 which has a piston or drilling tube terminating in high pressure drilling fluid (not shown) and also in drill head 52. Includes a device for introducing the piston device. A drilling fluid seal 54 is provided, which may be chevron-shaped as shown. The front end of the guide pipe 46 is fitted with a coupling 46 to the main body of the guide pipe.
formed into a curved whipstock 46d attached by c. Whipstock 4
6d includes a curved body adapted to bend or reorient the piston body 90 degrees from a generally horizontal direction to a generally vertical direction.

In operation of the system, the piston or drilling tube 50 is moved forward as shown by the high pressure pump in the housing 48 by the drilling fluid pressure exerting a force on the fluid pressure region on the aft side of the drill head. Pressed to the left. piston·
As the tube is forced through the whip stock 46d, a bending force is exerted that forces the tube to generally follow the curvature of the whip handle, thereby causing the tube to redirect downwardly into the formation. A tube straightening section 46e is provided at the forward end of the whipstock 46d. It is vertically oriented and inclined (e.g. 5-10 degrees) in the same general direction as the forward movement of the tube. In this way, the tube's A-turn contact with the pipe straightening device causes the pipe to straighten generally vertically, rather than continuing to curl backwards into its curvature and spiral path. I'll try to get it done soon. Drilling fluid is directed into the formation to provide slurry outwardly through one or more ports 52a of drill head 52, through which the drill head is forced to work with pressurized fluid. move easily under the forces of

The piston body, or tube, is sufficiently rigid to be able to advance in a straight line through the formation;
However, it can also be made of steel or other metals that are capable of undergoing the aforementioned plastic deformation. For example, a suitable wall thickness for this purpose is 36,000 to 70,000 psi for tubes in the 1 1/4 to 1 1/2 inch range.
Outer diameter 0.080~ with yield point or higher
It is a 0.125 inch steel tube.

The principle of operation of the guide pipe and piston assembly is more clearly illustrated in the embodiment of FIG. That is, a fluid seal 54 is provided between the stationary guide pipe and the movable piston arrangement so that high pressure fluid (e.g., 1000-10000 psi or more) from the housing 48 transfers high pressure forces to the drill head 52. In addition to moving it forward at relatively high speed. Pressurized drilling fluid is sealed 5
4 and the portion of the guide pipe in fluid communication with the entire length of the tube 50 upstream of this seal so that most of the force is directed toward the rear side of the drill head and forwards the drill head. Make it stand out. A small portion of the pressure is lost due to the drilling fluid emerging through port 52, but most of this force carries the drill head and drilling tube forward.

Downstream of the seal 54, significant internal radial pressure (hoop pressure) is applied to the normally rigid piston body tube (e.g., 1 1/4 to 1
It is formed to a wall thickness of 0.080 to 0.125 inch for a steel pipe in the range of 1/2 and is subjected to large pressure. This stress, together with the bending stress that occurs when the piston tube passes through a portion of the whipstock, causes the tube to be plastically deformed and redirected or bent over a relatively short radius from horizontal to vertical. Do it like this.

With the system of FIG. 2, vertical perforations are made without forming radial sections. The pressure behind the seal 54 causes the above-mentioned propulsion and cutting by the jet (hereinafter referred to as piston effect).
The length of the piston body downstream of the seal cannot be greater than the length of the beginning of the guide pipe upstream of the seal, as it must be maintained to perform. One of the great advantages of the illustrated system is that no pre-existing casing is required, and there is no need to drill pre-existing holes for the guide tube.

Referring to FIGS. 3 and 4, the drill of the present invention
One embodiment of the head is shown in these figures. A drill head 56 is attached to the forward end of the piston body 58, where appropriate by welding. As shown, the forward end of the drill head is generally circular and hemispherical in shape. Illustrated are spaced, generally forward facing ports 56b.
In addition, oval ports 56b are formed to lubricate the chips and prevent them from becoming bound in the formation to aid in fluidizing the chips surrounding the piston body as the piston body passes through the formation. Provision may be made to direct drilling fluid in a generally rearward direction to assist in moving chips rearwardly. Instead, all or one port is directed forward to maximize chipping.

5 and 6, the nose portion of the drill head of FIGS. 3 and 4 is illustrated in which one or more ports are shown in multiple diagonal directions. There is. That is, such ports are oblique in two different planes relative to the axis of the drill head. In this way, the jet creates a steel cut or slot wall that would otherwise be formed in front of the drill head by ports angled in one direction, possibly causing resistance in the drill head. Will. At least 10 mm from the axis in at least two different directions
By diagonally spaced ~30° apart, the jet of fluid shears the formation so that the drill head has the function of progressively shearing the saw cut in the formation of the kerf as it passes.

7 and 8, a combination of injection and production wells is illustrated. Here, a pre-existing well casing 90 is provided and four guide tubes 92, 94, 96 and 98 are provided at whipstocks 92a, 94, respectively.
a, 96a and 98a and are placed circumferentially within the guide tube. Whipstocks 92a and 96a project parallel to each other in opposite directions. In the same way, whip stock 94a
and 98a project parallel to each other in opposite directions and perpendicularly to the direction of whipstocks 92a and 96a.
Piston bodies 100, 102, 104 and 106 are directed downwardly through guide tubes 92, 94, 96 and 98, respectively, and these are redirected through respective whipstocks to form horizontal or radial portions 100a, 102
a, 104a and 106a are formed. The radial section thus protrudes horizontally into the formation every 90°.

In the center of the well casing 90 is a production tube or pipe 110 of conventional size and shape, which includes a conventional suction rod pump having a suction rod and piston valve shown schematically at 114 in FIG. tube 1
The bottom of 10 is a conventional slotted cylindrical section 110a, which is permeable to oil flow but impermeable to particulate matter, such as a wire mesh sand filter. remove.

Essentially, the embodiment of FIGS. 7 and 8 is a combined injection and production system. That is, after the radial portions 100a, 102a, 104a, 106a are in place and the bottom of the production tube 110 is in place in the sump at the bottom of the casing 90, hot fluid, such as steam, is It can be flushed through the directional section and out of the drill head to heat nearby oil-bearing formations and allow the oil to flow downward and laterally into the pool generally designated 116. can. There, oil is pumped to the surface in a conventional manner by a suction rod pump assembly. Thermal energy is used effectively. This is because some of the heat from the downward flowing steam is utilized to keep the upward flowing oil at a temperature at which it remains fluid when it is selected to the top of the well. be.

Referring again to FIG. 8, the system can be utilized for "steam soaking" as follows. After formation of the radial portions 102a, 104a, and 106a, these can be cut from their corresponding whipstocks and the whipstocks are pulled into the surface for possible reuse. The steam then flows downwardly through the well casing 90 to penetrate into the formation. A pump is placed in the basin as shown, and the oil heated by the steam is pumped to the surface so that it flows into the basin.

It is possible that the force applied to the drill head is sufficient to cause the piston body to move at a faster rate than the jet effectively fluidizes the formation in contact with the drill head. A device in the form of a restraint line may be provided to control the maximum speed of movement of the piston body. Such lines also serve to monitor the rate at which the drill head is advancing through the formation.

Systems of the type described above are characterized in that the radial section is formed in the system for heating subsurface formations for production in the same casing or in a remote casing, through which the fluid steams. Can be used to inject.

Once the drilling is complete, the system is sealed with some other equipment as shown in Figures 13 and 14 below. For example, the system can be sealed by flowing cement through a fluid downcomer or guide tube 30 into the area surrounding the piston body. If the opening in the drill head is insufficiently large to pass the required volume of steam or other fluid, the abrasive
Either the opening is placed in drilling mud to erode the opening to the desired size for fluid injection, or the opening is enlarged by the action of a suitable solvent. Drill heads can be completely severed by placing explosives in them.

Two additional embodiments of tube bending equipment are shown in the ninth
From the figure it is shown in FIG. In both examples,
The well must be of sufficient diameter in terms of size and shape to permit the introduction of these devices. In FIG. 9, a housing 151 surrounds a portion of a tube bending device 152. In FIG. The bending device consists of a rigid body and is positioned to form a curved guideway 158. This guideway is compatible with the movement of the drilling tube through it, and the arrangement
When the head and tube are forced through the guideway by fluid pressure, the tube always contacts the plurality of sheaves and is bent to the desired radius. The tube straightening device 195 is located at the exit of the guideway and consists of a cross-shaped body 161 which is attached to the side plate 154. The body carries four sheaves, namely the upper and lower sheaves 16
2 and a sheave 163 on the opposite side. These sheaves have such a shape that their peripheral surface almost encompasses the entire circumference of the perforated tube.

When the perforation tube passes through the guideway 158,
It will be explained below that bending is accompanied by a certain change in its cross-sectional shape. More specifically, when Tube reaches the end of the guideway,
It has an oval cross-sectional shape rather than a circle. It has been found that straightening such tubes is sometimes more effective if it involves reshaping the tube into a circular shape. To accomplish this, sheave 163 is formed such that it applies a force to the existing perforated tube, changing it to a more or less circular shape, while at the same time applying a force that does not cause bending. In connection with the action of straightening the tube, sheaves 162 and 163 also cooperate with nearby sheaves 156 and 157.

In another embodiment, the cross-shaped tube straightener shown in FIGS. 9 and 10 is not used. Thus, as shown in FIGS. 11 and 12, the tube straightening apparatus can use only two upper and lower sheaves 162 in such cases.

Figures 13 and 14 illustrate an apparatus for introducing a drilling fluid, such as steam, into a drill head after a hole has been formed. This may be necessary if the effectiveness of a sliding seal suitable for the drive piston is not sufficiently airtight to completely confine the injection of steam into the piston body to heat the subsurface formations. This is the purpose of the steam seal described here. The above figure shows the guide.
Pipe 166 is shown together with a threaded coupling 167 between the sections of the guide pipe. Perforated tube 168 is shown passing through seal 164. The upper end of the boring tube 168 is provided with a threaded portion 171. guide·
The lower end of the upper portion of the pipe 166 also includes an internally threaded portion 172. Cup ring 167
The threads are the same as the threads on portion 172 of collar 171. More specifically, the threads for coupling the two parts of the guide pipe are left-handed threads, and the threads 171 and 172 are also left-handed threads. Hydraulic pressure is applied to the guide pipe through the borehole tube 168 and the drill head attached thereto laterally within the ore deposit, and it is now desired to introduce steam or other process fluid into the borehole tube. Assuming that the coupling ring 167 is removed by turning the upper part of the guide pipe 166 clockwise, it is then lifted up and turned counterclockwise to cut the threads. Portions 171 and 172 are brought into engagement. This provides a hermetically sealed metal-to-metal coupling. The part is then in the condition shown in FIG. Steam or other process fluid is now introduced through the guide pipe and through the perforated tube 168 and thence into the deposit.

Figures 13 and 14 also show an annular portion 173 at the inlet of portion 171, which has a shape that provides a downwardly converging entry opening. This is because it is from the larger inner diameter of the pipe 166 that the tube 16
This improves the flow characteristics of the device by providing a transition step to a smaller inner diameter of 8. Portion 173 is dimensioned to form a stop when threaded portions 171 and 172 are engaged.

FIG. 15 schematically shows a well 210 in the earth's crust extending downward to a deposit 211. In this case the well is shown with a casing 212 that can extend into a void 213 close to the formation 211 . In this case, the pipe extending into the well is pipe string 21.
4, in which a perforated tube 215 is normally placed. As shown in FIG.
16 is mounted within the pipe string 214 to form a seal between the pipe string and the perforated tube 215. When the perforated tube is generally extended as shown in FIG. 15, the upper end of perforated pipe 215 is above seal 216. Before the drilling tube is extended, it is in the pipe string 214 and its drill head 217 is attached to the seal 216.
located below. Structure 221 serves to carry a pipe bending device 222. While the seal 216 can be placed in a coupling between the sections of the piping string 214, it is preferably placed in a coupling near the upper end of the bending device 222. Pipe 249 is a fluid downcomer.

FIG. 15 also schematically shows a mobile production rig 224 and reels carrying trucks 225 carrying the supply of drilling tubes 215.

One embodiment of an extending whipstock or bending device is shown in FIGS. 16-18. It includes structure 22 that supports bending assemblies 226 and 227.
It consists of 1. Structure 221 has 228 on one side
It can be in the shape of a pipe that is cut out as shown in . Assembly 226 consists of a rigid mounting arrangement made of rigid side plates 229 attached to a back plate (not shown) and a top plate 231. This assembly is shown in structure 2 as shown at 232.
21 has been secured. Assembly 227 includes a rigid attachment formed by similarly connected side plates 233 which make a pivotal connection 234 with the lower end of assembly 226. The upper assembly 226 is a series of two rollers or sheaves 2
36 and 237 are supported. These are arranged to form a guideway and are dimensioned to receive the perforation tube 215. The lower assembly 227 similarly includes a series of two rollers or sheaves 23
9 and 240. This is positioned to form a guideway 242.

The bending device described above is extended to the position shown in FIG. 17 by swinging the lower assembly outward and upward. The guideway formed by each assembly is a section of the overall guideway formed when the lower assembly is swung into the position of FIG.

A suitable power system is provided to move the lower assembly to the extended position shown in FIG.
This is a cylinder/piston type hydraulic actuator 2
44, whose actuating rods are pivotally connected at side walls 233 and 246 of assembly 227. When hydraulic pressure is applied to the operator 244, it causes the lower assembly 227 to move into the first position.
It moves from the position shown in FIG. 5 to the position shown in FIG. 16. The continued application of hydraulic pressure to the operator 244, or hydraulic load, serves to hold the assembly in the position shown in FIG. 17 during passage of the drilling tube through the assembly and during subsequent drilling operations. Assuming the operator is single acting, the control valve for receiving and venting hydraulic fluid is closed after actuation to lock the assembly in the extended position. FIG. 14 shows tube 247 extending to the top of the well for hydraulic operation by operator 244.

When it is desired to utilize older bending equipment, the pipe string 214 may be
can be pulled upwardly along with housing 221 to force retraction of assembly 227 and crushing and tearing of the extended position of the perforation tube. If operator 244 is double acting, it is used as a power device to retract assembly 227 upon crushing or buckling the bore tube. The tube 215 is severed by the explosion or otherwise before the whipstock collapses.

As shown in FIG. 17, assemblies 226 and 2
A series of rollers or sheaves carried by 27 provides a continuous curved guideway through which the perforated tube passes to effect the desired bend. The sheave of each assembly engages the inner or outer wall of the curved tube. The tube bend is normally assumed to be 90°, but this may vary depending on specific requirements. As an example, the present invention proposes using steel pipe with a bend radius of 1 1/4 to 1 1/2 inches and a wall thickness on the order of 6 inches to 12 inches. enable. Tube metals, for example, have yield points of 36,000 to 70,000 psi or higher.

We generally believe that buckling or breaking occurs when the tube is bent to such a relatively short radius. However, the fact that the tube does not buckle or fail is attributed in part to the presence of relatively high pressure fluid within the tube as it is deformed through the bending device. This imposes hoop stresses on the metal wall in conjunction with the stresses exerted during bending.

Referring again to FIG. 17, the sheaves 239a, 23
It will be noted that the sheaves 9b, 239c, and 239d and the opposing sheaves 240a, 240b, and 240d are arranged rather than creating a straight guideway. The purpose of these sheaves is to form a tube straightening device so that the bore tube leaving these sheaves is relatively straight. Sheaves 239d and 240
d is large in diameter and has a peripheral groove so that it surrounds almost the entire circumference of the tube. This arrangement thus serves to exert a straightening force on the tube as it exits the guideway. In addition to applying a non-bending force to the tube to straighten it, the sheave 2
39d and 240d have a force that causes the tube to change shape from an oval cross section to a more circular cross section.

In order to stiffen the structure 221 against lateral pressing forces, its upper end is shown attached to a girder extension 221a, which is a section of pipe that extends a considerable distance into the well casing 212.

The way in which the extendable whipstock is used in practice is as follows. Assuming that the well was drilled with conventionally used equipment, and assuming that the void 213 was formed proximate to the deposit 211, the portion of the drill string 214 is the lowest point attached to the member 251 of the tube bending equipment. Assembled with cup ring. A suitable length of drilling tube is provided with a hydraulic jet type drill head 217 at one end thereof. This is there,
The drill head is assembled into the drill string with the drill head at or slightly below the seal 216. A suitable length of the perforated tube is sufficient to extend laterally the required distance and further ensure that the upper open end of the tube is sufficiently above seal 216 when the tube is extended as shown in FIG. the length plus the length that is sufficient to ensure that drill string 2
14 assembly is attached to the housing 221
and bending device 222 are now lowered into the well, with the bending device now in the retracted condition. Once the bending apparatus reaches the level corresponding to the deposit, the upper end of the pipe 214 is connected to a source of hydraulic fluid (ie, water) at a relatively high resulting pressure, such as from 1000 psi to 10000 psi or more. In an alternative and preferred method, the drill head, including the whipstock, and the drill string, but not the drilling tube, are first lowered into the desired final position. There the drill head and drilling tube are lowered. Assuming we now desire to make a horizontal hole in our deposit, the bending device 222 is operated by the operator 24.
By applying water pressure to the pipe string 2, it is stretched as shown in Figure 15, and then high water pressure is applied to the pipe string 2.
14 is introduced at the upper end. Hydraulic fluid flows into and through the perforation tube 215 and, under the force of the fluid pressure field provided by the perforation tube together with the drill head 217, the tube is forced downwardly through the seal 216, bending device 222 and above. It is driven in a direction transverse to the strata according to the principle of The jet's drill head 217 penetrates the formation to form a laterally extending hole as shown in FIG. 15, for example. Upon completion of this operation, and assuming that the deposit is to be treated with steam or other fluid, the application of water pressure to the pipe string 214 is discontinued, a steam seal is formed, and the string is connected to the source of the treatment fluid. Connected at the surface of the well. In this way the device acts as a device that introduces a sufficient amount of treatment fluid into the deposit over an extended period of time.

The embodiment illustrated in FIGS. 19 and 20 has a separate tube straightening device. Rollers or sheaves 239d and 240 to straighten the tube
In place of d, there is a cross-shaped straightening device 251. This is a sheave 256 and 257 placed laterally.
It consists of sheaves 253 and 254 facing each other. The grooves around the periphery of these sheaves are proportionate, thereby enclosing almost the entire circumference of the tube. It has been found that although the perforated tube does not collapse during bending, there is plastic deformation in the metal wall section, so that when the tube exits the guideway, its cross-sectional shape is slightly oval rather than circular. There is. Rollers 256 and 257 are positioned so that when the tube passes between them, lateral pressure acts on the side walls of the tube to change the cross-sectional shape to some extent to approximate a circle. This, along with the action of sheaves 239a-239c and 240a, 240b, assist in straightening the tube so that the portion of the tube extending from the straightening device into the formation further straightens the desired force of the drill head. It has been found to be straight enough to be transmitted into the formation without straightening.

The embodiment of FIGS. 22-25 also includes a plurality of sheaves forming an arcuate guideway for the bending device. However, the bending device is
It is made up of three assemblies instead of the two as shown in Figure 7. Also provided is a device for straightening the adjustable tube. Housing 261 may be the same as housing 221 of FIG. The tube bending device consists of three assemblies, each forming one section of the arcuate guideway. Assembly 262 comprises rigid side walls 266 secured together in spaced relationship and housing 261.
is fixed to the upper part of the The ends of the side walls are shown connected by closure lids or cover plates 266a and 266b. assembly 263
consists of similarly spaced connected walls 267, the upper ends of which are connected to the side walls 26 of the assembly 262.
6 and has a pivoting connection. Wall 267 is also shown connected by closure lids or cover plates 267a and 267b. Assembly 264 also comprises spaced walls 269 connected to the lower end of wall 267 and having a closing lid or cover plate 269a269b.

22 and 23 show the housing structure 261 retracted. 22nd assembly
The power plant is extended to the position shown in the housing 2
61 and whose actuating rod 274 comprises a hydraulic operator 272 pivotally connected at 276 to the side wall of assembly 264. The side walls of assemblies 262 and 263 form their mutually proximal ends 276 and 277 such that they enter into full abutting engagement when the bending device is fully extended. Opposite ends 278 and 2 of the side walls of assemblies 263 and 264
79 is formed in the same way. Instead of a power operator, assembly 264 can be connected to a tension cable that extends to the top of the well.

When operator 272 is hydraulically actuated, assemblies 262, 263, and 264 move toward end 276.
and 277 and ends 278 and 279 into abutting engagement and are extended to the control position shown in FIG.

Each of the assemblies 262, 263 and 264 includes:
A plurality of rotating sheaves are positioned to form a continuous tube bending guideway that progressively bends the perforation tube as the tube is driven through the perforation tube when the plurality of assemblies are extended. have The guideway is generally arcuate, with assemblies 262, 263 and 264 forming segments of the arc. The sheaves for assembly 262 are represented at 281 and 282, for assembly 263 the sheaves are represented at 283 and 284, and for assembly 264 at 286 and 28.
It is represented by 7. Sheave 286a, 286b, 28
6c, 286d and 286e and 287a, 28
7c, and 287e cooperate to straighten the bore tube before it exits assembly 264. In a preferred case, sheave 287c is adjustable to adjust the straightening force on which it is applied. Therefore, in FIG. 25, it is the structure 28
Structure 288 is then pivotally connected to a pin or shaft 289 carried by the side wall of assembly 264 . The positioning of sheave 287c can be adjusted relative to sheaves 286b, 286c and 286d by adjusting screw 291. In order to increase the straightening effect, the sheaves 286b, 286
c and 286d are shown placed with their centerlines arched upward (FIGS. 23 and 24). The sheave 287e is not important for the straightening operation and may be omitted. The main points of adjustment of sheave 287c are also applicable to the embodiments of FIGS. 9, 11 and 16.

As in FIGS. 16 and 17, the sheave 28
6e and 287e are sized and grooved such that they nearly surround the circumference of the bore tube. These sheaves can also change the shape of the tube to some extent to almost circular.

The embodiment of FIGS. 22-25 functions in much the same way as the embodiment of FIGS. 16-20 when extended. However, when retracted, it is more compact. This is because assemblies 262, 263 and 264 have straight shapes. Also operator 2
As 72 is energized to extend the assembly, assembly 264 begins to
71 and 272 and is followed by assembly 263.

It is desirable to introduce water into assemblies 262, 263, and 264 as the perforation tube is being driven through the bending device and into nearby formations. A small duct 293 is thus shown in FIG. 24, which redirects water from above the seal 292 towards the assembly 262. Duct 293 drains into assembly 262, or it connects with ducts 294, 295, and 296 in the side walls of the assembly. The latter ducts are positioned to communicate when the assembly is extended. Duct 296 discharges the water spray from nozzle 297. Introducing water tends to clean the guideway and prevent blockages or the sheave from becoming jammed due to the intrusion of foreign objects (such as sand or small rocks).

Closing lids or cover plates on assemblies 262, 263 and 264 are used to keep out rocks and other debris. In some cases holes are punched into these plates.

[Brief explanation of drawings]

FIG. 1 is a side elevational view, partially in section, showing a drill string assembly with a prior art surface arrangement and an expanded, partially truncated well casing and a radial section formed in accordance with the present invention; Figure 2 is a partial cross-sectional schematic illustration of an assembly of the invention moving horizontally through a whipstock and redirecting vertically; Figures 3 and 4 show the drill head and piston body, respectively; Side and End Views: Figure 5 is a cross-sectional view of the drill head and a single aperture; Figure 6 is a cross-sectional view of the same aperture as in Figure 5 taken along line 6--6; Figures illustrating the diagonal-diagonal orientation of one of the several ports in the embodiment: Figure 7 is a cross-sectional view of the casing containing the four radials and the corresponding whipstock device with the central production cord; Figure 8 A cross-sectional view of the system of FIG. 7 taken along line 8--8; FIG. 9 is a detailed side view of another embodiment of the tube bending device; FIG.
10 is a view towards the exit of the guide passage with the tube bending and straightening device of FIG. 9; FIG. 11 is a detailed side view of another tube bending and straightening device: 12 is a detailed view looking towards the outlet end of the guideway of FIG. 11; FIG. 13 is a detailed side view of the device for creating a hermetic connection for introducing steam into the perforated tube; and FIG. Cross-sectional view: Figure 14 is similar to Figure 13, but shows the connection after the introduction of steam has been decided: Figure 15 shows a well placed in an underground well with a perforation tube extending into a lateral borehole. Side view showing the outline of the device: No. 16
The figures are a detailed side view showing the tube bending device of FIG. 14 and its installation; FIG. 17 is a detailed cross-sectional elevation view showing the tube bending device in side view and enlarged view; FIG. 18 is a detailed side view showing the tube bending device and its installation; Figure 17 is a view looking towards the right; Figure 19 is a detailed cross-sectional view showing another embodiment of the invention in side view; Figure 20 is a view looking towards the right of Figure 19; FIG. 21 is a detailed view in section showing the sealing device between the pipework of the well and the borehole tube; FIG. 22 is a side view, partially in section, of another embodiment with a guide device in three sections; FIG. Figure 23 is a front view looking towards the right side of Figure 21:
24 is a front view similar to FIG. 22, but showing the tube bending device on an enlarged scale; FIG. 25 is a cross-sectional enlarged view of the bore tube straightening adjustment device showing details. In the figure, 24... Production rig, 22... Geological formation, 28... Well (oil well) casing, 30...
Guide tube, 34...Perforation tube, 36
. . . drill head, 32a . . . whipstock device, 38 . . . fluid downcomer pipe.

Claims (1)

Claims: 1. An apparatus for forming a borehole in a subsurface formation, comprising: a guide pipe having an internal fluid seal and having one end connected to a source of pressurized fluid; a perforated tube disposed within said guide pipe in sealing engagement with a seal, said perforated tube being movable through the other end of said guide pipe to the outside of said guide pipe; One end of the perforated tube is open and in fluid communication with the guide pipe, and the other end of the perforated tube is configured such that pressurized fluid introduced into the guide pipe exerts a fluid force on the perforated tube;
A device characterized in that it is closed so as to move the perforation tube like a piston into the formation through the guide pipe. 2. Apparatus according to claim 1, characterized in that it includes a drill head having at least one through fluid outlet port at the closed end of the drilling tube. 3. Apparatus according to claim 1, characterized in that the drill head has no device for imparting rotation thereto. 4. The device according to claim 2, wherein at least the forward part of the drilling tube of the drill head projects beyond the guide pipe into the subsurface formation, so that the forward part is below the ground surface. A device characterized in that it is surrounded by a stratum of earth. 5. Apparatus according to claim 1, characterized in that the apparatus includes means for supplying pressurized drilling fluid to the fluid passageway of the borehole tube. 6. The apparatus of claim 1, wherein a sealing device is attached to the inner surface of the guide pipe and provides fluid sealing engagement with the perforated tube. 7. A device according to claim 1, characterized in that the device includes a device capable of forming a connection that brings the guide pipe and the perforation tube into communication. 8. Apparatus according to claim 1, characterized in that the guide pipe is placed in a well casing that projects into a region of subsurface geological formations. 9. The apparatus of claim 8, wherein the apparatus includes a downcomer pipe aligned with the guide pipe and mounted on the well casing. 10. A device according to claim 1, characterized in that the device includes a restraint device operatively associated with the piston for controlling the maximum speed of movement of the perforation tube relative to the guide device. A device that does this. 11. Apparatus according to claim 2, characterized in that at least one of the ports of the drill head extends in two different planes in a direction oblique to the axis of the piston arrangement. 12. The apparatus of claim 2, wherein the apparatus includes a rearwardly facing port in the drill head. 13. The apparatus of claim 1, wherein the apparatus is configured to move the perforated tube at a substantial angle relative to the axis of the guide pipe as the perforated tube moves through the guide pipe. Apparatus characterized in that it includes a whipstock device near the forward end of said guide pipe for changing direction. 14. Apparatus according to claim 13, characterized in that the perforated tube is formed by a rigid metal wall capable of undergoing plastic deformation. 15. The apparatus of claim 13, wherein the whipstock device includes a plurality of connected assemblies that bend an arcuate tube when extended from a retracted position within the structure. Forms a guide path, and water pressure guides and
When hooked onto the pipe, the tube is adapted to be propelled downwardly through the guide pipe and through the guideway, thereby bending the tube and forcing the drill head laterally into the formation. Apparatus characterized in that it has a series of projecting sheaves, each of said assemblies rotatably supported by said assemblies to form part of an arcuate guideway when extended. 16. The apparatus of claim 13, wherein a series of sheaves supported by each assembly are arranged on the outward side of the curvature of the bore tube for effecting successively increasing bends of the bore tube. A device characterized in that it is arranged to engage the wall of a perforation tube. 17. The apparatus of claim 13, wherein a first upper assembly of the bending device is secured to the structure, its lower end being pivotally connected to one end of the next lower assembly, and Apparatus characterized in that it has a power device for moving the lower assembly from a retracted position within the structure to an extended position in which the structure forms an arcuate guideway in relation to the first assembly. 18. Apparatus according to claim 13, characterized in that it includes a device for straightening the tube supported by the outlet end of the lowermost assembly. 19. The device according to claim 18, wherein the device for straightening the tube is configured to apply bending forces in opposite directions on the upper and lower sides of the tube in order to straighten the tube. Apparatus comprising a sheave disposed at a lowermost assembly, said sheave being supported by a lowermost assembly. 20. The device according to claim 18, wherein the tube straightening device engages the side wall of the exiting tube to change the cross-sectional shape of the exiting tube from an oval shape to a more substantially circular shape. Apparatus characterized in that it comprises opposed sheaves arranged to meet and press together. 21. The device according to claim 19, wherein the device for straightening the tube is in the form of a cross comprising upper and lower rollers positioned to engage the upper and lower sides of the tube. Apparatus characterized in that it comprises side rollers that engage and press against the side walls of the assembly and tube. 22. The device according to claim 20, wherein the two side rollers are separated by a distance such that the tube changes its cross-section from oval to approximately circular when it passes between the side rollers. Featured device. 23. The device according to claim 13, comprising three connected assemblies (each a first, a second
and a third assembly) are used,
the first assembly is pivotally connected at its lower end to a second assembly, and the second assembly is connected at its lower end to a third assembly, the first assembly being fixed to the structure;
The apparatus also includes a power device coupled to the third assembly for extending the second and third assemblies relative to the first assembly to form an arcuate guideway. 24. The device according to claim 18, wherein the device for straightening the tube includes a sheave adapted to exert a force on the tube outside the curvature of the tube and an adjustable sheave for rotatably mounting the sheave. A device characterized in that the sheave can be moved forward or backward relative to the tube. 25. Apparatus according to claim 13, characterized in that the apparatus includes a device for introducing water into the bending device during application of hydraulic fluid under pressure to the piping. 26. The device according to claim 13, wherein the whipstock device includes a device forming a curved guideway through which the guide tube is forced when pressurized hydraulic fluid is applied to the guide tube. and wherein the whipstock guideway includes a rotatable roller or sheave arranged to engage and apply a force to the perforation tube to bend the perforation tube. 27. An injection device for injecting a treatment fluid radially into the subsurface formation through a downwardly directed borehole placed in a predetermined position in the subsurface formation, the injection device having a sealing device mounted therein and having a sealing device installed at the forward end. A long guide pointing downwards that terminates in the whip stock.
an assembly including a pipe and a tube having a head at a forward end and open at a rearward end, the head having at least one fluid outlet port, and a rearward portion of the tube in fluid sealing engagement with the sealing device. is retained in said guide pipe in a condition such that a passageway is formed extending from said rear end of said guide pipe through said tube to said head, said tube projecting radially into said formation from said whipstock. including the front part,
An injection device whereby treatment fluid supplied to the rear end of the guide pipe flows into the formation through a port in the head. 28. The apparatus of claim 27, wherein the apparatus includes at least a second assembly disposed within the well casing, the guide pipe of the second assembly being collinear with the one assembly. an injection device, characterized in that the whipstocks of the two assemblies are close to each other; 29. A method of drilling into underground mineral formations, comprising a guide pipe arrangement and a drilling tube therein, the drilling tube having a hydraulic jet type drill head, at least one hole at the forward end of the drilling tube. A method of drilling into an underground mineral deposit stratum using a drilling system having multiple ports and an open end at the other end, the method comprising: (a) placing the drilling tube in a guide pipe and opening the rear of the drilling tube; (b) directing pressurized drilling fluid into the guide pipe and thence into the drill tube; Drill the
A method consisting of the steps of moving the drill head and borehole tube into the formation. 30. The method of claim 29, wherein the drill head does not rotate to any significant extent as the drilling fluid flows through the port. 31. A method according to claim 30, characterized in that the drilling fluid is directed through at least one port of the drill head in two different planes with respect to the axis of the piston arrangement. How to do it. 32. The method of claim 30, including the step of bending the perforation tube through a whipstock to direct it laterally into an adjacent formation. 33. The method of claim 32, wherein the perforated tube is formed by a solid wall of normally solid metal that deforms plastically when changing direction. 34. The method of claim 32, wherein the guide pipe is placed within a well casing and the drill head passes pressurized abrasive fluid exiting the drill head through the whipstock. a method comprising: means for directing erosive formation of an opening in the well casing as the well casing rotates; 35. The method of claim 32, wherein the guide pipe is placed within an existing well casing prior to step (b). 36. The method of claim 32, including the step of stopping the flow of drilling fluid through the drilling tube after completion of the drilling operation and then allowing process fluid to flow through the tube and into the formation. How to do it. 37. The method of claim 32, wherein the tube is in contact with a rotating sheave during bending, and after bending the tube is straightened.