RU2573301C2 - Self-elevating drilling offshore unit of ice class with single conic pile-supported leg - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention relates to extraction of mineral resources and may be used for drilling of oil and gas wells. The drilling system comprises a drilling unit and single conic leg. The drilling unit is comprised of a floating hull with ice deflector section, self-elevating legs and self-elevating device. The hull has ice-deflecting shape. The self-elevating device is designed to lift legs from the sea bottom and push them downwards to the sea bottom. A single conic leg is fixed to piles. Piles are driven into the sea bottom. Inclined surface of the conic leg comes in contact with ice around the hull.

EFFECT: potential extension of drilling season in areas exposed to ice impact.

27 cl, 8 dwg

Description

This invention relates to mobile offshore drilling bases, often referred to as "self-lifting" drilling bases or drilling rigs that are used in shallow water, typically at depths less than 400 feet (122 m), for drilling oil and gas wells.

In the never-ending search for hydrocarbons, many oil and gas reservoirs have been discovered over the past more than one hundred and fifty years. Many technologies have been developed to search for new reservoirs and reserves, and in many areas in the world exploration work has been carried out, giving new discoveries. The discovery of new unexplored reserves near populated areas and in accessible places is unlikely. Instead, large new reserves are opening up in problematic and elusive areas.

One promising area is the coastal zone of the Arctic. However, the Arctic is remote and cold, where ice on water creates significant difficulties for the exploration and production of hydrocarbons. For many years, in general, it is believed that six unprofitable wells should be drilled for each profitable well. If this is actually true, it is necessary to make the construction of unprofitable wells inexpensive. However, in the Arctic there is practically nothing inexpensive.

Currently, in shallow water in places with cold weather, such as the Arctic, self-elevating or mobile offshore drilling bases can be used for about 45-90 days in a short period of open water in the summer season. Prediction of the beginning and end of the drilling season depends on random factors, and a lot of effort is spent on determining the moment of safe towing of the self-lifting base to the drilling site and the beginning of drilling. After the start of construction, it is critical that the well be completed on time to prevent involuntary disconnection and retreat in the event ice arrives before the well completes. Even during several weeks of open water, floating ice floes pose a significant risk to self-elevating drilling rigs, when the drilling rig is on site and the legs of the self-elevating drilling rig are exposed and highly vulnerable to damage.

Self-elevating drilling rigs are mobile autonomous rising offshore drilling and overhaul platforms and are equipped with supports made with the ability to descend to the seabed and then raise the body above the water. Self-elevating drilling rigs usually include drilling equipment and / or overhaul equipment, a support lifting system, residential compartments, loading and unloading facilities, storage areas for bulk and liquid materials, a helipad and other necessary facilities and equipment.

The self-elevating drilling rig is structurally designed to be towed to the drilling site and lifted on supports above the water so that sea waves act only on supports that have a very small cross-section, thus ensuring the passage of waves without communicating significant movement of the self-lifting drilling rig. At the same time, the supports of the self-elevating rig are poorly protected from collision with floating ice floes, and a floating ice of any substantial size can cause structural damage to one or several supports and / or push the rig from the site. If such an event occurs before the completion of drilling and completion with the installation of appropriate protection, a hydrocarbon leak may occur. Even a slight risk of such a leak is completely unacceptable in the oil and gas industry to supervisors and the public.

Thus, after determining that a potentially cost-effective well has been drilled during this short season, a very large-sized, self-supporting system or similar structure can be delivered and installed on the seabed for a long-term drilling and hydrocarbon production process. Data held by its own weight is very large and very expensive, but able to withstand the forces of ice throughout the year. Any opportunity to reduce the cost of development in the Arctic without risk can save significant money.

The invention relates to a self-elevating ice class drilling rig for drilling for oil and gas in potentially ice conditions on coastal sea areas, including a floating hull having a relatively smooth deck in its upper part. The floating hull additionally includes a mold for bending ice in its lower part, passing around the perimeter of the hull, the mold for bending ice passes from the hull area near the deck level and goes down to the area near the bottom of the hull. A section of the ice deflector is made passing around the perimeter of the bottom of the body to direct ice around the body, and not under the body. At least three supports are installed in the perimeter of the bottom of the hull, while the supports are made with the possibility of lifting from the seabed to ensure towing of the rig through shallow water, as well as extension to the seabed and additional extension for lifting the hull partially or completely out of the water. A self-lifting device is connected to each support and serves both to lift the support from the seabed, giving the ice-class self-lifting rig an opportunity to swim due to the buoyancy of the hull, and pushing the supports down to the seabed and pushing the hull up with partial exit from the water when floating ice floes threaten drilling rig, and with the exit completely out of the water when ice is absent. The system further includes a single conical support on the pile base having a housing extending from the support part below to the upper deck at the top, the supporting part being attached to the pile base with piles driven into the seabed when a single conical support on the pile base is installed to use. A single conical support body on a pile base includes an inclined surface coming into contact with ice around the body, extending from a wider lower zone to a narrower upper zone, where the lower zone is located below the sea surface and the upper zone is located above the sea surface. The drilling rig is capable of working on a single conical support on a pile base with lifting the casing above the water and extending above a single conical support on a pile base for drilling downward through a single conical support on a pile base, lowering it into water to go to the ice protection position, when in this, the ice should come into contact with the ice-caving form of the rig when thin ice is present, and the possibility of withdrawal when thick ice is present.

The invention further relates to a method for drilling wells in waters prone to ice. The method includes creating a single conical support on a pile base having a hull with a supporting part at the bottom and an upper deck at the top and an inclined surface coming into contact with ice around the hull extending from a wider lower zone to a narrower upper zone where the lower zone is located below the sea surface, and the upper zone is located above the sea surface. Piles are driven into the seabed and attached to a single conical support to secure a single conical support to the seabed. A drilling rig is created having a floating hull with a relatively smooth deck in its upper part and with an ice-bending mold in its lower part, the ice-bending mold extending from the hull region near the deck level and extending down to the region near the bottom of the hull. A portion of the ice deflector is created, passing around the perimeter of the bottom of the hull to direct ice around the hull, not under the hull. At least three supports are installed in the perimeter of the bottom of the housing. Each support extends downward so that the shoes from the bottom of the supports come into contact with the seabed and lift the body up and out of the water when ice does not threaten the rig, when the rig drills a well at the rig site. The casing is additionally lowered into the ice protection configuration so that the ice caving mold extends above and below the sea surface to cave in the ice going to the rig to allow the ice to sink into the water and apply bending forces breaking the ice, while the ice bypasses drilling rig. A well is drilled from a rig beyond the edge of the deck and down through a single conical support on a pile foundation.

A more complete understanding of the present invention and its advantages gives the following description with the accompanying drawings, which show the following.

Figure 1 shows a side view of the present invention, where the drilling rig is afloat and ready to be towed to the drilling site.

Figure 2 shows a side view of the present invention, where the drilling rig is raised above the water.

Figure 3 shows a side view of a first embodiment of the present invention, where the drilling rig is partially lowered into the ice-water interface, but continues to be supported by supports in a protective configuration for drilling in potentially ice conditions.

FIG. 4 is an enlarged side view of one end of a first embodiment of the present invention of FIG. 3 with ice moving onto a drilling rig.

Figure 5 shows a side view of a drilling rig moving to a single conical support on a pile foundation for drilling downward through a single conical support on a pile foundation.

Figure 6 shows a side view of a drilling rig mounted above a single conical support on a pile foundation for drilling downward through a single conical support on a pile foundation.

Figure 7 shows a side view of the drilling rig in its configuration of protection against ice mounted adjacent to a single conical support on a pile base.

On Fig shows a top view of a drilling rig installed for drilling down through a single conical support on a pile base.

When considering the detailed description of the preferred device or devices of the present invention, it should be understood that the features of the invention and concepts may appear in other devices and that the scope of the invention is not limited to the described or shown embodiments. The scope of the invention is limited only by the scope of the claims below.

Figure 1 shows a self-elevating ice class drilling rig, generally indicated by arrow 10. Figure 1, a self-elevating drilling rig 10 is shown with a hull 20 afloat at sea and supports 25 in a raised position, where most of the length of the supports 25 towers above deck 21 of hull 20. On deck 21 is a derrick 30 mounted on a drill console 24 and other conventional equipment and systems for drilling wells. In the configuration shown in FIG. 1, a jack-up drilling rig 10 may be towed from one prospected field to another and to or from the base on shore for maintenance and other onshore operations.

When the self-elevating drilling rig 10 is towed to the drilling site, generally in shallow water, the supports 25 are lowered through openings 27 in the housing 20 until the shoes 26 at the lower ends of the supports 25 come into contact with the seabed 15, as shown in FIG. 2. In a preferred embodiment, the shoes 26 are connected to the support caissons 28 to secure the drilling rig 10 to the seabed. After connecting the shoes 26 to the seabed 15, the lifting devices in the openings 27 raise the housing 20 from the water on the supports 25. When the housing 20 is completely raised from the water, any impact of the waves and the stormy sea bypasses the supports 25, creating a reduced load in comparison with the impact of the waves on a large floating object such as hull 20.

When ice begins to form on the surface of the sea 12, the risk of contact of floating ice with the supports 25 and damage to the supports or simply the demolition of the self-elevating drilling rig 10 from the drilling site becomes very high for conventional self-lifting drilling rigs, and such drilling rigs are usually removed from the drilling sites at the end open water season. Ice class self-elevating drilling rig 10 is designed to withstand ice floes due to ice protection created by the hull in a displacement position, as shown in FIG. Figure 3 shows that ice usually dampens waves and waves of the sea, so that the sea surface 12 seems less threatening, however, the dangers of the marine environment only change, not decrease.

When the ice class self-elevating drilling rig 10 adopts an ice-protective configuration with the housing in the displacement position, the housing 20 is brought into contact with water, but not so much that the housing 20 floats. A significant portion of the weight of the drilling rig 10 preferably continues to act on the supports 25 to secure the drilling rig 10 to the drilling site, in a position of resistance to any pressure that the ice field may exert. The drilling rig 10 is lowered so that the inclined ice-bending surface 41, as best shown in FIG. 4, overlaps the sea surface 12 to come into contact with any floating ice that may be suitable for the drilling rig 10.

The inclined ice-bending surface 41 extends from a ledge 42 located on the edge of the deck 26 to the neckline 44. The ice deflector 45 extends downward from the neckline 44. Thus, when a floating ice floe, such as shown at 51, approaches the drilling rig 10, the ice-bending surface 41 immerses the leading edge of the floating ice 51 under the sea surface 12 and exerts a significant bending force, breaking large ice floes into smaller, less destructive and less dangerous pieces of ice. For example, it can be assumed that an ice field of hundreds of feet, and possibly miles across, could approach a rig 10. If a floating ice floes into pieces less than twenty feet (6 m) long, such pieces may bypass a rig 10, causing significantly less fear.

Shown in figure 5, a single conical support on a pile foundation, in General, is indicated by the position 60, pre-installed on the seabed. A single conical support 60 on a pile foundation is a structure that can be used in places near the coast in areas exposed to ice with significantly reduced costs compared to a conventional gravity type structure. A single conical support 60 on a pile foundation includes a housing 65, a support part 67 and an upper deck 70. The support part 67 is preferably in the form of a flange with holes or perforations spaced around the perimeter of a single conical support 60 on a pile base. The support portion 67 is adapted to be supported on the seabed 15. Although a single conical support 60, standing on a pile base, rests on the seabed, the weight of a single conical support on a pile base preferably carries a plurality of piles 68, driven deep into the seabed 15 and then attached to a single conical support 60 on a pile base. Typically, piles 68 are driven to a depth of about 35 to about 75 meters into the seabed to permanently secure a single conical support 60 on a pile foundation, at a site near the shore. Piles 68 are typically sturdy pipes or pipe structures that work like long nails and provide an efficient design for stationary platforms for offshore drilling and hydrocarbon production operations. Piles have a relatively large diameter of 1 to 3 meters and wall thicknesses of about 2 to about 10 cm. One particular advantage of the present invention is that for the weight of a single conical support 60 on a pile foundation supported by piles 68, a slight or no preparation of the bottom layer before installation is required, and any preparation of the bottom layer is reduced, in principle, to creating a flat area on the seabed for installing a single conical support 60 when piles 68 are installed. The bottom layer containing soft silty materials does not need to be removed and replaced with more durable materials.

To install a single conical support 60 on a pile foundation supported by piles 68, preparation of the seabed for installation is minimal or not required. Since piles 68 are buried in the seabed and firmly attached to the supporting part 67, piles 68 provide resistance to: (a) forces causing the structures to slide along the seabed, (b) forces that cause the structures to tip over, such as forces acting several meters higher supporting part of the structure; and (c) forces causing vertical movement both up and down. Resistance to both up and down movement is important for the resistance to tipping forces that ice can apply. Piles 68 on the front side of a single conical support 60 on a pile base resist the lifting forces that ice can exert from the upstream side, i.e. tipping resistance, and piles 68 on the back side or downstream side of a single conical support 60 on a pile base resist downward movement in which the back side is pressed into the seabed 15. Using such long piles creates a structurally effective support part for year-round operations in ice-affected areas in the coastal environment, resisting ice loads, which can be very significant. Piles act like nails that hold the platform in place and are structurally more effective than gravity bases, where the overturn resistance is created only by the size and weight of the structure.

The length and number of piles 68 should depend on the magnitude of the predicted vertical and lateral forces and the strength of the soil layers into which the piles are driven. Preferably, the piles are strategically placed around the periphery of the support portion 67 to provide resistance to the shear and tipping forces with maximum structural efficiency. The support portion may include at least eight and preferably at least 16 piles and up to 64 piles around the periphery at intervals that can maximize structural efficiency and create a pile of piles where several piles work together to resist lateral forces and bearing a single conical support 60 on a pile base. Piles 68 usually extend to a depth of 35 to 75 meters into the bottom layer, depending on the predicted loads and soil strength parameters. A single conical support 60 on a pile base is shown as an octagonal multifaceted structure, but circular or ring configurations can also be used. Preferably, the structure is multifaceted for ease of manufacture, having six, eight or even 12 sides, preferably all of the same size, and a single conical support 60 on a pile base is symmetrical.

The casing 65 of the single conical support 60 on the pile base includes an inclined ice contact surface 72 extending from a level below the sea surface 12 to a level above the sea surface 12, so that ice in the sea, in particular floating ice, comes into contact with the casing 65 on an inclined surface 72 contact with ice. The ice contact surface 72 extends around the periphery of the single conical support 60 on the pile base so that ice from any direction should come into contact with the housing 65 on the ice contact surface 72. The inclination of the ice contact surface 72 causes any ice slabs to rise along the inclined surface and bend to the point of destruction, and typically ranges from 40 degrees to 60 degrees to the horizontal and, more preferably, about 55 degrees to the horizontal. Lumps of cracked ice, called debris, should extend around hull 65, driven by a sea current or wind. Above the ice contact surface 72, a single conical support on a pile base includes a mold for turning ice pushed out to the upper point of the ice contact surface 72. Deck 70 is located on top of a single conical support 60 on a pile base and can be equipped with a base plate for drilling several wells.

A single conical support 60 on a pile foundation is a massive structure, typically with a deck size of 70 over 75 meters across. One advantage of a strong and large single conical support on a pile foundation over a gravity type structure is, in general, reduced weight or, more specifically, specific gravity before ballasting with water. Solid ballast material is generally not required for a single conical support on a pile foundation. The gravitational type design usually has a specific gravity from 0.21 t / m ³ to 0.25 t / m ³ , a single conical support on a pile foundation can be designed with a specific gravity from 0.20 t / m ³ to about 0.18 t / m ³ . Often gravity-type structures require solid ballast to increase weight to create resistance to shear and upheaval. When using piles or a pile of piles 68, a single conical support 60 on a pile foundation can be designed with reduced weight. The reduced specific gravity of a single conical support on a pile foundation can also be translated into a decrease in the cost of manufacture and transportation, which does not include a reduced installation cost due to the exclusion of the cost of preparing the site on the seabed, which is required for large-sized systems with gravity-type structures, and the cost of ballast material with high specific gravity, often added to the structure of the gravitational type.

Although single conical supports 60 on a pile foundation can be equipped with a rig and systems for drilling wells, cost savings are obtained if the wells can be drilled with a self-elevating drilling rig, since a single conical support on a pile foundations can be made slightly smaller and, of course, only save from downsizing, not to mention cost savings for all drilling equipment and systems. Drilling a well through a single conical support on a pile foundation using an ice class drilling rig, such as drilling rig 10, provides additional cost savings since the drilling rig does not require towing from the site at the first sign of ice. More wells can be drilled per year with an ice-class 10 drilling rig, which can remain on the job site longer in the fall when other drilling rigs are long gone.

With a single conical support 60 on a pile base fixed to the seabed 15, the rig 10 moves to the site as shown in FIG. 5 and is set to drill down through a single conical support 60 on a pile base, as shown in FIG. 6. The supports 25 of the ice class 10 drilling rig require a stronger structure than conventional supports and withstand limited ice loads. At the same time, if there is a threat of ice load above the limit, the ice class 10 can remain at the place of work, stop drilling operations and adopt the ice protection configuration, as shown in Fig. 7. When the ice leaves, drilling can resume, and when the ice becomes too thick, the rig 10 can be removed from the site until the next drilling season. The shape of the housing 20 (as well as its strength) provides for the bending of ice and its destruction and increases the time window for drilling, which significantly reduces costs for sites exposed to ice. Although preferably the drilling rig 10 is mounted adjacent to one of the faces of a single conical support on a pile base, as shown in Fig. 8, it can be approached from any direction, as shown at 20A.

The housing 20 preferably has a multifaceted or multilateral shape, which gives the advantages of a round or oval shape and can reduce the cost of manufacture. The plates from which the case is assembled can then be flat and the fact that the entire structure contains parts of a flat material such as steel should reduce its complexity. The ice-breaking surface preferably extends at least about five meters above the water or sea surface 12, taking into account that sea levels rise and fall under the influence of tides and storms and, possibly, other factors. The height above the sea surface takes into account the significant thickness of the ice with hummocks rising above the sea surface 12, but since the height of the ledge 42 above the sea surface 12 is sufficient, ice of large thickness should be crushed down when it comes into contact with the rig 10. At the same time, deck 21 from above hull 20 should be high enough above the waterline so that the waves do not roll around the deck. Therefore, deck 25 is preferably located at least 7-8 meters above the sea surface 12. Conversely, the neckline 42 is preferably located at least 4-8 meters below the sea surface 12 to adequately bend the ice to break them into harmless parts. Thus, the hull 20 preferably has a height in the range of 5-16 meters from the plane of the bottom to deck 20, more preferably 8-16 meters or 11-16 meters.

It should also be noted that the supports 25 and the openings 27, in which the supports are connected to the body 20, are located around the perimeter of the ice deflector 45, while the possibility of ice contact with the supports decreases when the drilling rig 10 is in the ice protection configuration shown in FIG. 3 and sometimes referred to as a configuration with a housing in a displacement position. In addition, the drilling rig 10 should not respond to every threat from ice floes with a significant increase in the cost of production of oil and gas companies. If rig 10 can extend the drilling season by just a month, this could mean a fifty percent improvement in some ice-prone areas, and therefore create significant cost savings in the industry.

In conclusion, it should be noted that consideration of any link is not an assumption that it relates to a known technique for the present invention, in particular, any link that may have a publication date after the priority date of this application. At the same time, without exception, the claims below are included in this description as an additional embodiment of the present invention.

Although systems and methods are described in detail herein, it should be understood that various changes, substitutions, and substitutions can be made without departing from the spirit and scope of the invention as defined by the claims below. A person skilled in the art can study preferred embodiments and identify other ways of implementing the invention that are not described herein. The inventors believe that the variations and equivalents of the invention are defined by the scope of the claims, while the description, nature and drawings should not limit the scope of the invention. The scope of the invention is specifically limited by the claims below and their equivalents.

Claims (27)

1. A system for drilling for oil and gas and oil and gas production in potentially ice conditions on coastal sea areas, containing:
a drilling rig having a floating hull with a relatively smooth deck in its upper part and an ice-bending shape in its lower part extending down and inward around the hull perimeter, where the ice-bending mold extends from the hull area near the deck level and passes down to the area near the hull bottom ;
a section of an ice deflector passing around the perimeter of the bottom of the hull to direct ice around the hull, and not under the hull;
at least three supports installed inside the perimeter of the bottom of the floating hull, while the supports are capable of lifting from the seabed to tow the rig through shallow water, as well as extension to the seabed and additional extension to lift the hull partially or completely out of the water; and
a self-lifting device connected to each support both for lifting the support from the seabed so that the ice-class self-lifting drilling rig can float due to the buoyancy of the hull, and pushing the supports down to the seabed and pushing the hull completely out of the water when there is no ice; and
a single conical support on a pile base having a body with a supporting part below and an upper deck on top, the supporting part being attached to piles driven into the seabed when the construction of a single conical support on a pile base is installed for use, while the inclined surface comes into contact with ice around the hull and passes from a wider lower zone to a narrower upper zone, with the lower zone located below the sea surface and the upper zone located above the sea surface;
while the drilling rig is made with the possibility of lifting the hull above the water and drilling through a single conical support on a pile base, lowering it into the water to move to the ice protection position, while the ice can come into contact with the ice-bending form of the drilling rig when thin ice is present , and should be cleaned when thick ice is present. 2. The system according to claim 1, further comprising a securing mechanism connected to the shoe of each support, to create additional resistance to the forces that floating ice can transmit to the drilling rig. 3. The system according to claim 1, in which the curving ice surface deviates up and out from the neckline of a reduced size to a ledge of an increased size. 4. The system according to any one of paragraphs. 1-3, in which the curving surface of the ice extends vertically at least 8-10 or more meters. 5. The system according to claim 4, in which the angle of the curving surface of the ice has a value in the range of 30-60 degrees from the vertical. 6. The system according to any one of paragraphs. 1-3 and / or 5, in which the housing of a single conical support on a pile base has at least a size of 60 meters across, and the design of a single conical support has a specific gravity of less than about 0.20 t / m ³ . 7. The system according to claim 4, in which the housing of a single conical support on a pile base has at least a size of 60 meters across, and the design of a single conical support has a specific gravity of less than about 0.20 t / m ³ . 8. The system according to any one of paragraphs. 1-3, 5 and / or 7, in which the piles go deep 35 meters below the supporting part or deeper. 9. The system according to claim 4, in which the piles go 35 meters deep below the support part or deeper. 10. The system of claim 6, wherein the piles extend 35 meters deeper below the support portion or deeper. 11. The system according to any one of paragraphs. 1-3, 5, 7, 9 and / or 10, in which the piles go into the depths of 50 meters under the supporting part or deeper. 12. The system of claim 4, wherein the piles extend 50 meters deep below the support portion or deeper. 13. The system of claim 6, wherein the piles extend 50 meters deeper below the support portion or deeper. 14. The system of claim 8, wherein the piles extend 50 meters deeper below the support portion or deeper. 15. A method of drilling a well in waters prone to ice, in which:
provide a single conical support on a pile base having a hull with a supporting part below and an upper deck at the top and an inclined surface coming in contact with ice around the hull, extending from a wider lower zone to a narrower upper zone, where the lower zone is located below the sea surface, and the upper zone is located above the sea surface;
fix the piles to the seabed and attach to a single conical support on a pile base to secure a single conical support on the seabed;
provide a drilling rig with a floating hull having a relatively smooth deck in its upper part and an ice-bending form in its lower part, the ice-bending form extending from the hull area near the deck level and extending down to the area near the bottom, and an ice deflector section passing around the perimeter of the bottom of the body for directing ice around the body, and not under the body;
provide at least three supports installed in the perimeter of the bottom of the housing;
lower each support so that the shoes at the bottom of the supports come into contact with the seabed and lift the body up and out of the water when ice does not threaten the rig, when the rig drills a well at the drilling site;
the body is lowered into the ice protection configuration, with the ice bending form passing above and below the sea surface to bend the ice entering the drilling rig to allow the ice to submerge under water and applying bending forces breaking the ice, while the ice bypasses the drilling rig ; and
drill a well beyond the edge of the deck and down through a single conical support on a pile foundation. 16. The method according to clause 15, in which the stage on which piles are driven, further comprises driving piles with a diameter of at least 1 meter, at least to a depth of 35 meters into the seabed. 17. The method according to p. 15 or 16, in which the curving surface of the ice extends from the ledge to the neckline, and the step of lowering the hull into the water, in particular, includes lowering the hull into the water so that the neckline is at least 4 meters below the sea surface, and the ledge is at least 7 meters above the sea surface. 18. The method according to p. 15 or 16, further comprising the step of lifting the hull from the water when the threat from floating ice is reduced. 19. The method according to 17, further comprising the step of lifting the hull from the water when the threat of floating ice is reduced. 20. The method according to any one of paragraphs. 15, 16 and / or 19, in which the stage at which the piles are driven further comprises driving the piles with a diameter of at least 1.5 meters, at least to a depth of 50 meters into the seabed. 21. The method according to 17, in which the stage at which the piles are driven, further comprises driving piles with a diameter of at least 1.5 meters, at least to a depth of 50 meters into the seabed. 22. The method of claim 18, wherein the step of driving the piles further comprises driving the piles with a diameter of at least 1.5 meters, at least to a depth of 50 meters into the seabed. 23. The method according to any one of paragraphs. 15, 16, 19, 21 and / or 22, in which the step of driving the piles further comprises driving the piles with a diameter of at least 2 meters, at least to a depth of 60 meters into the seabed. 24. The method of claim 17, wherein the step of driving the piles further comprises driving piles with a diameter of at least 2 meters, at least 60 meters deep into the seabed. 25. The method according to p. 18, in which the stage at which the piles are driven, further comprises driving piles with a diameter of at least 2 meters, at least to a depth of 60 meters into the seabed. 26. The method according to claim 20, in which the stage on which the piles are driven, further comprises driving piles with a diameter of at least 2 meters, at least to a depth of 60 meters into the seabed. 27. A method of drilling wells in waters prone to ice, comprising using a drilling rig and a single conical support on a pile base according to any one of paragraphs. 1-14.

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