LOW GROUND PRESSURE AND AMPHIBIOUS CORING SYSTEM

Abstract

An amphibious coring apparatus is provided for operations on ground including wetlands. A rig deck is supported above a substructure. The substructure has mobile, low ground pressure, wetland-engaging ground components. Between the deck and the substructure is an articulation interface for leveling the rig deck. A top drive is movable in a derrick for rotating a drill string. Hydraulic rams supported from the deck raise and lower the top drive, such as by a cable extending over a sheave at a top end of each ram. A pipe handler racks pipe to and from multiple tiers and a live bottom trough assists with tripping pipe.

Description

CROSS-REFERENCE TO RELATED INVENTION

This application is a regular application of U.S. provisional patent application Ser. No. 60/940,443, filed May 28, 2007, the entirety of which is incorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to apparatus and methodology for obtaining subterranean core samples, more particularly for drilling apparatus which exert low ground pressure and having synergistic adaptations related thereto.

BACKGROUND OF THE INVENTION

Sensitive environments including wet terrain, such as muskeg and swampy areas, are an impediment to drilling and coring operations as the fragile environment is easily damaged.

Accordingly, many such operations have been restricted to the winter season when conventional equipment can be supported on frozen ground. The usable window for a winter season in Alberta, Canada can be as small as three months before a thawing break-up approaching the spring season.

SUMMARY OF THE INVENTION

Embodiments of the invention relate to low ground pressure or to amphibious capable equipment for accessing sensitive environments year around, including after the winter thaw. The apparatus of the invention imposes less than one-half the pressure of the human foot and use of environmentally friendly hydraulic fluids, in a substantially all-hydraulic rig, minimize risk.

Embodiments of the invention relate to equipment which can be transported to the sensitive areas on conventional transports and within restrictions including weight and size. Accordingly, components of the equipment which are oversize when erected for operation, can be collapsed or pivoted to a low profile, such as for hauling on a low-boy trailer.

Embodiments of the invention further relate to equipment which can adapt to uneven terrain, without extraneous leveling jacks or blocking. The low-ground profile or amphibious equipment includes an articulated platform which can be leveled relative to the equipment's mobile base.

In one broad aspect of the invention, an amphibious coring apparatus is provided for operations on ground including wetlands comprising: a rig deck; a substructure supporting mobile, low ground pressure, wetland-engaging ground components; and an articulation interface between the rig deck and substructure for leveling the rig deck. The articulation interface can be stabilized with lateral and longitudinal bars.

The apparatus of the current invention enables drilling over wetlands in all seasons. In a broad aspect a method is provided for drilling in wetlands comprising: moving an amphibious, low ground pressure coring apparatus onto the wetlands supported on wetland-engaging ground components, and articulating a rig deck relative to the ground components for orienting a derrick for drilling.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an embodiment of the invention on site and illustrating a transportable drilling/coring apparatus placed adjacent a transportable mud unit;

FIG. 2 is a perspective view of an embodiment of the transportable drilling/coring apparatus with the plating of the deck removed for viewing the structures therebelow;

FIG. 3 is a top view of an embodiment of the rig with the derrick erected;

FIG. 4 is a bottom view of the rig of FIG. 3;

FIG. 5A is a front elevation of the derrick illustrating the top drive at the rig deck;

FIG. 5B is a perspective view of the derrick of FIG. 5A;

FIG. 5CB is a close up perspective view of the rams and sheaves of the derrick of FIG. 5A;

FIG. 6 is an elevation view of an embodiment of the transportable drilling/coring rig;

FIG. 7 is a front elevation view of the rig of FIG. 6;

FIG. 8 is a front, underside and perspective view of a deck, the articulation interface and the substructure having the pontoons removed for improved viewing of the interface

FIG. 9 is a rear perspective view of a deck, the articulation interface and the substructure having the pontoons removed for improved viewing of the interface;

FIG. 10 is a perspective view of one embodiment of the pipe handler showing a rack only on one side;

FIG. 11 is an end view of the pipe handler of FIG. 9 illustrating racks on either side of the pipe handler;

FIG. 12 is a perspective view of the mud unit and deck with the pontoons and tracks removed;

FIG. 13 is a left side view of the mud unit of FIG. 12 illustrating the articulation interface between the deck and the substructure;

FIG. 14 is a front view of the transportable frame of FIG. 13,

FIG. 15 is a perspective view of auxiliary transportable unit; and

FIG. 16 is a rear view of the auxiliary transportable unit of FIG. 15.

DESCRIPTION OF EMBODIMENT OF THE INVENTION

In greater detail and with reference to FIG. 1, embodiments of an apparatus for coring or drilling comprise a rig 10 that can work in wetlands year around. Typically the rig 10 is associated with other equipment such as at least a mud unit 100.

The rig 10 is amphibious (including land, water, muskeg, big and combinations thereof), comprising: a rig deck 11 and a substructure 12 which supports ground-engaging, motive, ground components M like wheels or tracks. The ground components M impose a low ground pressure on the supporting wetland. In one embodiment, the ground components M of the substructure 12 can comprise pontoons 13 fit with tracks 14 so that the rig 10 is both mobile over soft ground and can be amphibious. The tracks 14 can be driven with systems similar to skid-steer equipment. Suitable pontoons, tracks and drive systems can be sourced from Wetland Equipment Company, Inc., Louisiana, USA.

As shown in the embodiment of FIGS. 2-4, a rig deck-mounted diesel engine 19 provides hydraulic power for driving the tracks 14. The tracks 14 can be driven by one or more drives comprising hydraulic motors 21 and a drivetrain (such as gearboxes 22, chain and sprocket arrangements 23) which can be fit to the substructure 12 for driving the tracks 14. The diesel engine 19 also provides hydraulics generally for the rig 10 overall.

Drilling and coring operations utilize pipe 30 which, for most operations, can be racked on the rig deck 11. Best seen in FIGS. 1, 8 and 9, a pipe racking system 32 enables pipe 30 to be loaded and unloaded at horizontal racks 33 supported on the rig deck 11. The rig 10 includes a driver's cab 34 and a doghouse 35 housing coring/drilling controls.

With reference to FIGS. 5A-5C, a hydraulic top drive 42 is guided in a dolly 43 up and down the derrick 40 for rotating pipe 30. Conventional equipment is provided, such as hydraulic lines and mud hoses 44 are not detailed. Further, other conventional equipment includes pipe handling such as iron roughneck and power tongs, hydraulic bails and elevators, power slips and automated tripping.

With reference also to FIG. 2, the top drive 42 is actuated up and down the derrick 40 using one or more actuators, such as a pair of hydraulic rams 45. Each ram 45 comprises a cylinder 46 secured to the deck 11 at a lower end and stabilized laterally in the derrick at an upper end, at about one half the height of the derrick. Each ram 45 further comprises a rod 47 for extension from each cylinder 46 and operable from about one half the height of the derrick to the top 48 of the derrick. Full range of motion of the top drive 42 from rig deck 11 to the top 48 of the derrick is accomplished with a cable (not shown), one end of which is fixed such as to the deck 11, extends over a sheave 49 fit to each rod 47, and the other end being secured to the top drive dolly 43. When the rod is fully retracted to the cylinder 46, the top drive is at the deck 11. As the rod 47 is extended, the cable passes over the sheave, doubling the displacement of the top drive 42 relative to the rod 47. The top drive travels twice the lineal travel of the rod. Accordingly, extension of rod of ½ of the derrick, moves the top drive 42 from the deck 11 to the top 48 of the derrick. Lifting loads from the top drive 42 are directed to the rig deck 11 through the rams 45 and avoid imposing vertical loads on the derrick 40, eliminating crown loads and enabling a lightweight derrick design. The derrick 40 is fit with a hinge 44 (FIG. 1) adjacent a deck end for pivoting from an upright, substantially vertical, operational position to a substantially horizontal and low shipping or transport position. Depending on the form of transport, the entire rig 10 including derrick 40 can be transported between sites at or below road height restrictions for road transport.

With reference to FIGS. 6 and 7, typically a drilling derrick 40 is oriented vertically or otherwise oriented for particular operations. The derrick 40 is supported by the rig deck 11, the rig deck is supported on the substructure 12 and the substructure is supported by the substructure's ground components M. Due to uncertain wetland conditions, the orientation of the substructure 12 is less likely to be optimal for the derrick orientation. Accordingly, an articulation interface 15 is employed between the rig deck 11 and substructure 12 for orienting the rig deck 11, typically oriented to the horizontal for orienting the derrick 40 vertically thereon. Accordingly, articulation interface, or leveling system, operative between the deck and the ground components M enables the unit to be operated on zero-ground disturbance locations including off-level footing.

As shown in FIGS. 6-9, the deck 11, whether it is for the rig 10 or mud unit 100, is articulated upon the articulation interface 15, and actuable to level the deck 11, regardless of an uneven orientation of the substructure and ground components (pontoons 13 and tracks 14 shown). Typically, the deck 11 is supported above the substructure 12 upon a three or a four point connection. As shown in FIGS. 6 and 7, the deck 11 can be pivoted on a three-point articulation interface 15, two points forward and one point rearward wherein one forward point and one rearward point are elevation adjustable. At least two jacks are required; one for side-to-side and one for front-to-back adjustment. Three jacks 50 are illustrated for connection to front pivots 51 and rear pivot 52. Two front jacks 50f,50f are located at two laterally spaced front pivots 51d,51d and 51s,51s, at each of the deck 11 and substructure 12 respectively, towards the front of the rig 10. One substantial rear jack 50r and rear pivot 52d,52s, at each of the deck 11 and substructure 12 respectively, is located towards the rear of the deck 11. The front pivots 51,51 are spaced forward of the rear pivot 52. The two front jacks 50f,50f actuate at least side to side leveling and can participate in some front to rear adjustment. The rear jack 50r and the one or more front jacks 50f,50f can actuate front-to-back leveling. The rear and front pivots 51,52 are distributed under the deck 11 for load distribution to the substructure 12.

A four point articulation interface comprises four points of connection, two points forward and two points rearward, and at least forward point and one rearward point being elevation adjustable.

With reference to FIGS. 8 and 9, a pair of lateral stabilizing bars 54 are provided, one forward and one rearward, extending between the deck 11 and the substructure 12, to ensure the deck 11 stays aligned and stabilized side-to-side over the substructure 12. Similarly, at least one longitudinal bar 55 is provided to ensure the deck 11 stays aligned front-to-back over the substructure 12. The bars are articulated at each connection, one end to the deck and another end at the substructure. The bars are provided in embodiments in which the jacks 50 are highly articulated and additional stabilization is desired.

In embodiments having a pair of parallel, spaced tracked pontoons 13, the pivots 51,52 and jacks 50f,50f,50r are fit between the tracked pontoons 13. The jacks 50 can be articulated actuators such as hydraulic rams.

With reference to FIGS. 10 and 11, an embodiment of the pipe racking system 32 includes a pipe rack 33, which can include a pipe handler 60 and one or more tiers 63 for storing pipe 30, and multi-tiers 63 (five tiers illustrated in FIG. 2, with multi-tiers obscured by pipe 30). One exemplary, lowermost, tier 63 is shown in FIG. 10. The pipe handler 60 can be automated for loading and unloading pipe 30 from each tier 63. The pipe handler 60 is actuated to both elevate, to access tiers 63, and tip for loading and unloading pipe 30 to and from the selected tier of the racks 63. The pipe handler comprises a trough 67 and a conveyor 66 positioned under the trough 67 for directing pipe 30 therealong.

A conveyor 66 and pipe trough 67 is supported on height adjustable trough supports 68 (one shown). Each trough support 68 is adjustable to position the trough 67 at each tier 60. Best seen in FIG. 11, each support 68 can be a tubular support 69 movably and axially actuable through a sleeve 70. The trough supports 68 can be actuated using one or more hydraulic rams. The trough 67 is pivotable left and right for receiving and unloading pipe 30. The trough 67 has a live bottom trough for assisting with tripping pipe 30. When a pipe 30 is lowered by the top drive 42, the conveyor 66 is actuated to direct a pipe end away from the derrick 40 and to lie the pipe 30 down in the pipe handler trough 67 for subsequent tipping and racking in a tier 63.

With reference to FIGS. 12 and 15 respectively, the rig 10 of FIG. 1 is typically accompanied by the mud unit 100 (FIG. 12) for drilling operations and can further include an auxiliary unit 200 (FIG. 15). Similarly, the mud unit 100, and even the auxiliary unit 200, can also be articulated for leveling purposes.

With reference to FIGS. 12-14, an embodiment of the mud unit 100 also comprises a working deck 11 for support on a substructure 12 (typically interchangeable with the substructure of the rig 10. The working deck 11 typically supports a mud pump, mud tank, mix hopper, shaker, degasser and auxiliary equipment including hydraulic power pack and air compressor. As shown in FIG. 14, an articulation interface 15 can be similarly provided as described for the rig 10 including rear pivot 52 and front pivots 51,51.

Suitable equipment and capacities possible include 1.7M³ Gardner Denver pump at 1000 psi, Mission 5 by 6 centrifugal pumps for precharge, mixing and mud roll, a Derrick 313M shaker, and a 20 m³ tank according to Alberta Energy Utility Board (EUB) regulations. Sensors monitor tank level, pumps and alarms.

The substructure can be convertible so that the pontoons and tracks can be swapped out for a substructure supporting large footprint tires and suitable drives (not shown).

As shown in FIG. 11, an embodiment of the rig 10 and mud unit 100 are setup on location for conducting operations. The units are ideal for shallow core drilling in the order of 300 m and support services and scaled-up rigs are contemplated to core drill to depths of 700 m.

The rig 10 has a low ground impact and is suitable for environmentally sensitive areas. Applicant believes that the rig footprint is about ½ of the footprint of other similar coring rigs. One embodiment of the rig is 38 feet by 44 feet. Accordingly, the rig has a small location size requirement and can fit on smaller resource leases while still meeting other drilling regulations. Despite units weighing in the order of 110,000 pounds, the ground pressure is about 2 to 4 psi and will not compact muskeg. Further, using other arrangements of rig 10 and mud units 100, such as those being arranged end to end, coring can be performed off lease, on access roadways or on lease roads. As shown, with a derrick 40 fit with a pair of 6″ rams 45, the rig can implement a Range II derrick capable performance of 50,000 pound pull and a 20,000 pound push and typical coring depths of 300 m or so for oil sands deposits in Northern Alberta, Canada. Other capacities including Range III are contemplated. Auxiliary capability includes 12,000 pound working winch and a 3,500 core winch.

Having reference to FIGS. 13 and 14, an embodiment of an auxiliary unit 200 comprises an amphibious drive base with a deck 11 having water and vacuum capability with a picker for a variety of lifting duties. One such auxiliary unit can transport pipe, cores and equipment and store 15 m³ of water and a 15 m³ vacuum tank 201.

A suitable vacuum tank 201 is a Rebel 15 m³ tank meeting TC-412 tank specifications and fit with a Hibon VTB820 blower. The water tank can be fit with a Bowie pump. Further, the auxiliary unit can be fit with a steam system for cleaning duties such as rig-cleaning. A suitable crane or picker 202 could include a Hiab 166B-3CL Knuckle-boom picker.

The rig 10, mud unit 100 and auxiliary unit 200 can be transported by road on low-boy trailers and then self-powered on their drive bases to the coring/drilling location, including amphibious and muskeg locations. It is also contemplated that the decks of the units are separable from the drive bases for separate shipping by truck and trailers.

Claims

1. Amphibious coring apparatus for operations on ground including wetlands comprising:

a rig deck;

a substructure supporting mobile, low ground pressure, wetland-engaging ground components; and

an articulation interface between the rig deck and substructure for leveling the rig deck.

2. The apparatus of claim 1 wherein the ground components comprise tracked pontoons for low ground pressure support on the ground.

3. The apparatus of claim 1 wherein the articulation interface comprises three or more spaced points of connection, two of which are elevation adjustable for adjusting the fore-to-aft and side-to-side angles of the rig deck relative to the substructure.

4. The apparatus of claim 1 wherein the articulation interface comprises three points of connection, two points forward and one point rearward wherein one forward point and one rearward point are elevation adjustable.

5. The apparatus of claim 1 further comprising stabilizing bars extending between the deck and the substructure for lateral and longitudinal stabilization.

6. The apparatus of claim 1 comprising front and rear stabilizing bars extending laterally between the deck and the substructure for side-to-side stabilization and at least one longitudinal stabilizing bar extending longitudinally between the deck and the substructure for front-to-rear stabilization.

7. The apparatus of claim 1 wherein the articulation interface comprises four points of connection, two points forward and two points rearward and at least forward point and one rearward point being elevation adjustable.

8. The apparatus of claim 1 wherein the substructure further comprises two tracked pontoons for supporting the apparatus with 2 to 4 psi ground pressure.

9. The apparatus of claim 8 wherein the substructure further comprises one or more drives for powering the tracked pontoons.

10. The apparatus of claim 9 wherein the one or more drives are powered from the rig deck.

11. The apparatus of claim 1 further comprising a pipe rack supported on the rig deck.

12. The apparatus of claim 11 wherein the pipe rack further comprises an automated pipe handler for loading and unloading pipe.

13. The apparatus of claim 12 wherein the pipe rack further comprises:

one or more tiers for storing pipe, and wherein

the automated pipe handler loads and unloads pipe from each tier.

14. The apparatus of claim 13 wherein the pipe rack further comprises:

a trough; and

a conveyor positioned under the trough for directing pipe therealong.

15. The apparatus of claim 14 wherein the trough and conveyor are height adjustable for loading and unloading pipe at each tier.

16. The apparatus of claim 1 further comprising:

a derrick, wherein

the derrick further comprises a top drive, and one or more actuators for moving the top drive along the derrick.

17. The apparatus of claim 16 wherein the one or more actuators are hydraulic rams mounted between the deck and the top drive.

18. The apparatus of claim 16 wherein the one or more actuators are hydraulic rams comprise:

a cylinder supported by the deck;

a rod fit with a sheave; and

a cable extending over the sheave to the top drive, wherein the top drive travels twice the lineal travel of the rod.

19. The apparatus of claim 16 wherein the derrick is pivotally mounted to the rig deck between a substantially horizontal transport and a substantially vertical operational position.

20. A method of drilling in wetlands comprising:

moving an amphibious coring apparatus having a rig deck onto the wetlands, the apparatus having low ground pressure, wetland-engaging ground components; and

articulating the rig deck relative to the ground components for orienting a rig deck supported derrick for drilling.