RU2379460C2 - Floating platform for sea wells boring and production in arctic condition - Google Patents

Abstract

FIELD: oil-and-gas industry.

SUBSTANCE: floating platform for sea wells boring and production in Arctic conditions contains boring and production equipment, including drill stem, water separating casing string, lifting pipes and pump bars, at that the mentioned above tube and bar strings during an operation process equipped with a floating elements on their external surface, made as filled with gas nitrogen or inertial gas solid plates of welded detachable balloons. The platform equipped with an ice breaker for ice pressure protection and anchored to the bottom via anchors with cables, on which balloons fixed. In the casing water separation string installed location detectors, at its bottom part there is a window for connection with hole clearance, which during the boring covered with a pipe with a balance, hanged with a balloon cables on the platform. The external surfaces of the sea casing water separation string, boring pipes, lifting pipes, pump bars and balloons have a water protection cover, and can be made of steel or aluminium alloys, or ceramic metal or polymers.

EFFECT: invention provides production and boring equipment safety operation due to loads from casing string and drill stem, also pump bars and lifting pipes weight decreasing.

6 cl, 6 dwg

Description

The invention relates to the field of gas and oil industry.

Known equipment for drilling and operating offshore wells containing a platform, a drilling rig, a pump, drill and casing pipes, a rock cutting tool, an oil submersible pump and a rocking machine, which is the closest analogue (prototype) to the claimed invention (see US 4059148 A , CL E21B 7/12, publ. 11/22/1977, 13 pp.).

Known drill and casing pipes, pipes and rods for oil submersible pumps with upset ends, on which a tapered, external and internal thread is cut (see Johansen K.V. Sputnik Borovika. - M .: Nedra, 1981-199 pp. Gray Oil production, Forest - Moscow: Olimp Biznes CJSC, 2001. 230-240 pp. Muravyov V.M., Sereda N.G. Sputnik of the oilman. - M .: Nedra, 1971. - 233 p .; see Yu. V. Vadetsky Drilling of Oil and Gas Wells. - M .: ACADEMA, 2004, p. 63, table 213. Abubakirov VF Drilling equipment, reference book, volume 2. - M .: Nedra, 2008 p. 20, 34).

Known icebreakers for the destruction of ice (see Fried E.G. The device of the vessel. - L .: Sudostroenie, 1970. - 11 pp.).

The disadvantages of equipment for drilling and operating offshore wells are:

- when lowering drill string and casing pipes while drilling gas and oil wells, pipes and rods of submersible pumps to the bottom of the Arctic Ocean and into the well to a depth of 8000-20000 m, the own weight of the rods and pipes exceeds the tensile strength of steel, and therefore, destruction occurs pipes and threads in the connecting nodes, and when columns of pipes and rods are installed at the bottom of the well, stability is lost and destroyed; for the same reason, the working depth of the installation of plunger pumps is limited, which is 650-2900 m, the diameter of the plunger and the outer diameter of the pump and its performance are limited;

- the load on the hook, cable, winch and internal combustion engine increases when raising and lowering drill and casing pipes and on the details of the rocking machine of submersible pumps;

- drilling of wells from floating platforms at the North Pole has not yet been carried out, therefore, their protection from ice was not provided.

The technical result of equipment for drilling and operating offshore wells and protecting it from destruction by ice at the North Pole is to ensure the safe operation of the drilling rig during the drilling and operation of gas and oil wells, submersible pumps, rocking machines and floating oil platforms in ice.

To solve the problem, equipment for drilling and operating offshore wells, containing a platform, a drilling rig, a pump, drill and casing pipes, a rock cutting tool, an oil submersible pump and a rocking machine, is characterized in that the pipes and rods with a waterproof coating are made of steel, or titanium, or aluminum alloys, or cermets, or polymers, equipped with separate removable cylinders with a waterproof coating, filled with gaseous or inert gas under a pressure of 0.0001-188.4 MPa, solid cylinders for casing, water separator, casing, for drill or pump rods, while cylinders in the form of pipes will be external to them, drill and casing pipes as well as pump rods and pipes are produced in standard sizes in accordance with GOST, diameter the outer pipe of the cylinder 70-700 mm should be selected taking into account the existing diameters of the manufactured pipes in such a way as to provide such an annular space at which a certain allowable pressure inside the cylinder can be created to ensure The required buoyancy or welded cylinders made in the form of outer pipes with a diameter of 70-700 m and inner diameters of 42-169 and plugs, or welded construction cylinders with a waterproof coating are fixed on pipes and rods motionless, containing an outer pipe with a diameter of 70-700 m and plugs, cast cylinders are made of steel, or titanium, or aluminum alloys, or cermets, or polymers, or elastic material, and welded ones are made of steel, or titanium or aluminum alloys, cylinders are installed on pipes and rods at the ends of pipes and rods and in medium their parts, and on the pipe and rod columns the cylinders are installed at a distance of 0.5-8 m from each other, the casing columns with cylinders are connected to the main floating platform located in the ice, which is fixed by cables connected to the cylinders with a waterproof coating, filled with gaseous nitrogen or inert gas at a pressure of 0.0001-184.5 MPa, and anchors to the bottom of the ocean, on which the drilling rig, compressor station and oil loading tanks are connected, connected to the pipeline and plunger submersible pump, indicated circuit board the mold is equipped with an icebreaker to protect it from ice pressure, sensors are installed on the casing string to warn floating facilities about its location and a robot with a video camera to accurately determine the wellhead at the bottom of the ocean when installing the casing string into the borehole and inspected during operation, a drill pipe string with cylinders and roller cone with a diameter of 120-490 mm is located directly resting on the rock being destroyed when drilling a well or a drill pipe string with cylinders and roller cone The tent is located in the cavity of a pipe string with a diameter of 800-1000 mm with cylinders supported on the ocean floor for temporary use for the period of well drilling and installation of casing pipes. Windows at a distance of 0-5000 m from the bottom of the temporary pipe string and casing string are made. bottom of the ocean for the exit of cuttings destroyed by cutter and salt solution supplied through the channel of the drill pipe by a pump at a pressure of 25.4 MPa installed on a floating platform, a movable pipe with a load suspended on ropes from a cylinder is installed on the casing pipe to the platform, the inner cavity of which is made of a cylindrical or conical shape, repeating the cylindrical or conical shape of the casing at the location of the windows to overlap them after the completion of the well drilling.

The drawing shows equipment for drilling and operating offshore wells and protecting it from destruction by ice at the North Pole. The drawing a, b, c, d shows a General view of the drill and casing pipes, pump pipes and rods for submersible pumps with cast cylinders; drawing e shows a drill pipe string with roller cone drilling tool and a casing string with cast and welded removable cylinders and welded one-piece cylinders; the drawing f shows the columns of the pump pipes and rods of the submersible plunger pump and the casing string with cast and welded removable cylinders and welded one-piece cylinders.

Columns containing pipes 1, 2, 3 and rods 4 with a waterproof coating are made of steel, or titanium, or aluminum alloys, or cermets, or polymers, equipped with separate removable cylinders with a waterproof coating, filled with gaseous or inert gas under pressure 0, 0001-188.4 MPa of solid cast-iron cylinders 5 as for casing, water separating columns for drill or pump rods, while cylinders in the form of pipes will be external to them, drill and casing pipes as well as pump rods and pipes are produced as standard dimensions in accordance with GOSTs, the diameter of the outer tube of the cylinder 70-700 mm should be selected taking into account the existing diameters of the manufactured pipes in such a way as to provide an annular space at which a certain allowable pressure inside the cylinder can be created to ensure the necessary buoyancy, or welded cylinders 6 made in the form of external pipes 7 with a diameter of 70-700 mm, and internal 8 with a diameter of 42-169 mm and plugs 9, 10, or cylinders 11 of a welded structure with a waterproof coating are installed on pipes 1, 2, 3 and gakh 4 motionless, containing an outer pipe 12 with a diameter of 70-700 mm and plugs 13, 14, cast 5 cylinders are made of steel, or titanium, or aluminum alloys, or cermets, or polymers, or an elastic material, and welded 6, 11 from steel, or titanium, or aluminum alloys, cylinders 5, 6, 11 are installed on pipes and rods at the ends of pipes and rods and in their middle parts, and on columns 15, 16, 17 pipes and rods 18 cylinders are installed at a distance of 0.5 -8 m from each other, casing string 16 with cylinders 5, 6, 11 connected to the main floating platform 19, located in ice 20, which is fixed by cables connected to water-resistant containers filled with gaseous nitrogen or inert gas under a pressure of 0.0001-188.4 MPa and anchors to the ocean floor (cables, cylinders and anchors are not shown in the drawing), on which a drilling installation, a compressor station and oil tanks connected to the pipeline 17 and the plunger submersible pump 21 are installed, the platform is equipped with an icebreaker (not shown in the drawing) to protect it from ice pressure, sensors are installed on the casing string 16 22 for warning floating assets about its location and a robot with a video camera for accurately determining the wellhead at the bottom of the ocean when installing a casing string into the well and inspecting them during operation, a drill string 15 with cylinders 5, 6, 11 and rolling tool 23 with a diameter of 76-508 mm is located directly resting on the rock to be destroyed when drilling a well or a string of drill pipes with cylinders and rolling tool is located in the cavity of a pipe string with a diameter of 800-1000 mm with cylinders resting on the ocean bottom for temporary use (in the drawing, the string of indicated pipes with cylinders is not shown) for the period of drilling the well and installing casing 16, windows 24 are made at the bottom of the temporary pipe string and casing string at a distance of 0-5000 m from the ocean floor to exit the destroyed cone 23 of sludge and saline supplied through the channel of the drill pipe 15 by a pump (the pump is not shown in the drawing) under a pressure of 25.4 MPa installed on the floating platform 19, a movable pipe 25 with a load of 26 suspended on ropes with cylinders to the platform (ropes and cylinders are not shown in the drawing), the inner cavity of which is cylindrical or conical in shape, repeating the cylindrical or conical shape of the casing at the location of the windows 24 to overlap them after the completion of the well drilling.

The maximum gas pressure in the cylinders depends on the allowable gas and water pressure on standard drill pipes (for example, for a drill pipe of strength M with a diameter of 73 mm and a wall thickness of 11 mm, the allowable compressive gas and water pressure on the pipes is 188.4 MPa, and the minimum gas pressure in cylinders depends on the depth of immersion of the drill pipe in water).

The minimum diameter of the outer tube of the cylinder, equal to 100 mm, in the well is determined by the standard diameters of the drill pipes 42-169 mm, and the maximum - 450 mm is determined by the standard size of the bits equal to 120-490 mm. The largest diameter equal to 700 mm of the outer pipe of the cylinder located above the wellhead in the sea water is determined by the weight of the drill pipe string, which depends on the depth of the sea bottom and the depth of the well and the size of the cavity in which the rotor of the drill rig is located, for free descent into the well and lifting drill string with cylinders to the surface of the platform.

The maximum diameter of the outer tube of the cylinder, equal to 70-80 mm, is determined by the inner diameter of the standard pump tube, equal to 93 mm and 120 mm, the minimum diameter of the cylinder is determined by the outer diameter of the standard pump rod, equal to 22 mm, 25 mm, 32 mm and 42 mm .

The maximum diameter of the outer tube of the cylinder, equal to 450 mm, for the pump pipe is determined by the inner diameter of the standard casing pipe located in the well, and the minimum diameter of the cylinder is determined by the outer diameter of the standard casing pipe, 112.5 mm and 137.5 mm. As the depth increases, the diameter of the well decreases to 215.5, 175.5, 137.5 mm, and therefore, the outer diameter of the outer tube of the cylinder decreases.

The largest diameter equal to 550 mm of the outer pipe of the cylinder for a pump pipe located at the wellhead in the sea water is determined by the internal diameter of the standard pipe equal to 600 mm, and the minimum diameter of the cylinder is determined by the outer diameter of the standard pipe equal to 112.5 mm and 137.5 mm.

The distance between the cylinders is determined by the standard long drill and casing pipes, as well as sucker rods and pipes 6.8-11.5 m.

To prepare the salt solution in a tank filled with sea water, salt is added and it is mixed with special devices.

Equipment for drilling and operating offshore wells and protecting it from destruction by ice at the North Pole works as follows.

Before drilling, a drill pipe string 15 is assembled with cylinders 5, 6, 11 (see drawing a, e) filled with gas under pressure, and a rock cutting tool 23, such as a cone, and lowered to the bottom of the ocean. By using pressurized gas cylinders, the drill pipe string is elongated in the direction of the surface of the water.

A drill rig mounted on a floating platform 19 is driven into rotation by a drill pipe string 15 and a cone tool 23 with a diameter of 490 mm and, at the same time, saline is pumped to the bottom hole through the hoses, swivel, channels of the string of pipes and drilling tools with a pump under a pressure of 25.4 MPa. From this moment, the process of drilling a well in soft rocks begins. Destroyed drill cuttings and saline are carried from the well to the bottom of the ocean.

After that, a casing string 16 with windows 24 and a movable pipe 25 with a load of 26 without cylinders and with cylinders 5, 6, 11 from the surface of the water to the ocean floor, on which the robot with a video camera is installed, is lowered into the drilled well (in the drawing, the robot does not shown) to accurately determine the wellhead at the bottom of the ocean.

It is better to place the drill pipe string 15 with cylinders 5, 6, 11 and rolling tool 23 with a diameter of 490 mm in the cavity of the pipe string with cylinders and windows for temporary use (the indicated pipe string with cylinders and windows is not shown in the drawing) resting on the rock at the bottom of the ocean for the period of drilling and installation of casing pipes.

In this case, there is no need to use a robot with a video camera to find the wellhead at the bottom of the ocean.

Drilling in solid rock continues with a smaller diameter of the cone drill pipes with cylinders to the gas and oil layer of the rock. The removal of sludge and saline solution destroyed by the cone tool from the well is carried out by a pump through the windows 24 of the casing 16 to the bottom of the ocean. After completion of the well’s drilling, the ropes on the platform are released and the pipe 25 with the load 26 suspended from these ropes is lowered down and covers the casing windows 24, or with a lifting device, the rope connected to the movable pipe moves up and tears it away from the loop of the movable pipe, which moves down and blocks the specified channels.

Then the plunger oil pump (see drawing, e) is assembled connected to the columns of the sucker rods 18 with cylinders 11, for example, of a cylindrical-conical shape and pipes 17 with cylinders and they are simultaneously lowered into the casing 16 with cylinders 5 to the bottom of the well into oil layer to a depth of 8000-20000 m or more. The casing string 16 is connected to a floating oil platform 19.

The columns of pump pipes and rods with cylinders of the submersible plunger pump and the casing string with cylinders are constantly stretched in the direction of the water surface, therefore, the tensile and compressive load in the cross section of the pump pipes and rods and casing in the threaded connecting units is reduced by its own weight, and consequently, their long and safe operation during the operation of gas and oil wells is guaranteed.

In addition, during the operation of the pumping unit, the load on its parts is reduced and smooth movement of the pump plunger and rods is ensured.

You can use rocking machines with lower electric motor power and plunger pumps with a larger plunger diameter, and therefore increase their productivity.

To protect the platform from ice pressure on the body and prevent its movement relative to the wellhead, the platform is equipped with an icebreaker to destroy and clean ice along the perimeter of the platform.

It is impossible to drill oil and gas wells without an icebreaker and it is impossible to exploit them, because huge fields of ice 1.5-2.5 m thick are continuously moving, destroying everything that they met on their way.

Claims (6)

1. A floating platform for drilling and operating offshore wells in arctic conditions, comprising a drilling rig, a pump, drill and casing pipes, rock cutting tools, lift pipes and sucker rods, an oil submersible pump or a pumping unit, oil loading tanks associated with a pipeline and a submersible plunger a pump installed between the wellhead and connected to a floating platform, a marine casing riser with buoyancy elements fixed on its outer surface along the entire length, from characterized in that it is equipped with an icebreaker to protect it from destruction and displacement relative to the wellhead by an endless field of drifting ice, and a compressor station, while the buoyancy elements, in addition to the temporary separating casing string, in which the drill pipe string with cylinders and rock cutting tool are located on the period of drilling soft rock and installing in its cavity a string of marine casing pipes without cylinders for fastening the soft roof of the well and the same string of water separating casing pipes with by allones above the mouth of the indicated well over the entire height of the ocean water column to a floating platform for its long-term use, or drill pipe string with cylinders and rock cutting tool located directly resting on the rock being destroyed for the period of soft rock drilling and installation of a marine casing string without cylinders for mounting soft roof of the well with the installation on the specified column of the robot with a video camera for accurate determination of the wellhead at the bottom of the ocean and its inspection during operation and this columns of water separating casing pipes with cylinders above the mouth of the indicated well along the entire height of the ocean water column to the floating platform for long-term use, are mounted motionless on elevator pipes and sucker rods, and are made in the form of solid or welded removable cylinders filled with gaseous nitrogen or inert gas in the form of pipes with plugs, while the cylinders are installed along the entire length of the lift pipes and sucker rods, or are located at the ends and in the middle of the mentioned lift pipes and sucker rods, and the floating pl the mold is fixed to the bottom of the ocean with anchors with cables, on which cylinders filled with gaseous nitrogen or inert gas are fixed, sensors are installed on the marine casing riser to warn floating vehicles about its location and in its lower part there are windows for communication with the annulus, and on an outer surface of the marine casing riser has a load pipe suspended on ropes with cylinders from a floating platform, with the possibility of closing said windows in the process of rhenium and their periodic opening. 2. The platform according to claim 1, characterized in that the outer surfaces of the marine casing riser, drill pipe, lift pipes, sucker rods and cylinders have a waterproof coating. 3. The platform according to claim 1, characterized in that the casing marine riser, casing and drill pipes, lift pipes, sucker rods, welded and cast cylinders are made of steel. 4. The platform according to claim 1, characterized in that the drill pipe, welded and cast cylinders are made of aluminum alloys. 5. The platform according to claim 1, characterized in that the sucker rods and cast cylinders are made of cermet or polymers. 6. The platform according to claim 1, characterized in that the welded and cast cylinders are made of titanium.

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