Abstract: Systems and processes for subsea marine managed pressure operations. One system includes a modified riser joint configured to fluidly connect inline with one or more riser joints. The modified riser joint and the one or more riser joints are connected to form a riser connecting a floating vessel with a wellhead. The system further includes a subsea pressure management sub-system configured to be operatively and fluidly connected to the modified riser joint at a subsea location.

Abstract: A mud turbine apparatus includes a rotor including an inner ring configured to be positioned around a drill pipe, an outer ring that is positioned around and spaced apart from the inner ring, a plurality of magnets coupled to the outer ring, and a plurality of blades coupled to and extending between the inner ring and the outer ring. The apparatus also includes a stator including a housing configured to fit into an annulus between the drill pipe and a surrounding tubular, and to receive the outer ring at least partially therein, and a plurality of coils that communicate with the magnets, such that in a first mode of operation, the rotor rotates to assist fluid flow therethrough and decrease drilling fluid pressure in the annulus, and in a second mode of operation, the rotation of the rotor impedes fluid flow therethrough and increases drilling fluid pressure in the annulus.

Abstract: Systems and processes for subsea marine managed pressure operations. One system includes a modified riser joint configured to fluidly connect inline with one or more riser joints. The modified riser joint and the one or more riser joints are connected to form a riser connecting a floating vessel with a wellhead. The system further includes a subsea pressure management sub-system configured to be operatively and fluidly connected to the modified riser joint at a subsea location.

Abstract: A deployment tool that can be used on land, jack-up and floating drilling rigs. The tools is installed around a drillpipe tool joint making it independent of the drill string load path as well as independent of the drill pipe thread and drill pipe size. It is designed for the largest commonly used drillpipe size, so has a single outer dimeter configuration that can be adapted from the largest drillpipe to the smallest in use with simple mechanical adapters. Thus, one main tool and a set of adapters is all that is required. The tool may be used in the deployment of RCDs, for example in the landing of an RCD bearing assembly on an RCD housing, or in the deployment of tubing hangers, lining hangers, casing hangers or other or any other temporary completion tool.

Abstract: An electrically powered drilling rig, such as for slim hole drilling, includes a drilling floor positioned over a drilling well, a set of pieces of drilling equipment operable for drilling the well, a first enclosure being positioned remotely of the drilling well and at least one electric motor being housed within the first enclosure. The electric motor is operated to provide power to one or more of the set of pieces of drilling equipment. The electric motor is housed within the enclosure and is remote of the drilling well and provides a buffer therebetween to prevent sparks from reaching the drilling well, thereby decreasing a fire hazard. The electric motor may be powered by a mobile battery pack. The electric motor may power a hydraulic pump, which further provides hydraulic fluid under pressure to the pieces of drilling equipment.

Abstract: Systems and processes for subsea marine managed pressure operations. One system includes a modified riser joint configured to fluidly connect inline with one or more riser joints. The modified riser joint and the one or more riser joints are connected to form a riser connecting a floating vessel with a wellhead. The system further includes a subsea pressure management sub-system configured to be operatively and fluidly connected to the modified riser joint at a subsea location.

Abstract: The present invention discloses a wellsite system for electric drive fracturing, including a gas source, a power supply system, electric drive fracturing equipments, electric drive sand blenders, a sand supply equipment, a liquid supply equipment, instrumentation, and two high-low pressure manifolds, wherein the power supply system is a gas turbine generator set, the gas source provides fuel for the gas turbine generator set, the gas turbine generator set provides power for the electric drive fracturing equipments and the electric drive sand blenders respectively, the sand supply equipment and the liquid supply equipment are both connected to input ends of the electric drive sand blenders, output ends of the electric drive sand blenders are connected to the electric drive fracturing equipment through one high-low pressure manifold, the electric drive fracturing equipments are connected to a wellhead through the other high-low pressure manifold, the instrumentation is used for remote control of the electric dr

Abstract: A method for handling of hydrocarbons on an offshore platform includes the absence of emergency depressurisation for a fire. The method includes arranging the platform such that there is no mechanism for emergency depressurisation of a hydrocarbon inventory of the platform in the event of a fire, restricting the size of the platform such that evacuation of personnel can be achieved prior to escalation of a fire due to the lack of emergency depressurization, and permitting a fire to escalate by combustion of the hydrocarbon inventory after evacuation of the personnel.

Abstract: What is provided is a method and apparatus wherein a swivel can be detachably connected to an annular blowout preventer thereby separating the drilling fluid or mud into upper and lower sections and allowing the fluid to be displaced in two stages, such as while the drill string is being rotated and/or reciprocated. In one embodiment the sleeve or housing can be rotatably and sealably connected to a mandrel. The swivel can be incorporated into a drill or well string and enabling string sections both above and below the sleeve to be rotated in relation to the sleeve. In one embodiment the drill or well string does not move in a longitudinal direction relative to the swivel. In one embodiment, the drill or well string does move longitudinally relative to the sleeve or housing of the swivel.

Abstract: In a chip evacuation device that evacuates chips produced in a machine tool to outside of the machine tool, a synchronous motor is used as a power source for the chip evacuation device. A load on the synchronous motor is monitored and a number of rotation or a direction of rotation of the synchronous motor is changed when it is determined that the load exceeds a preset threshold.

Abstract: An RCD includes a housing, a seal assembly package, and a seal tube assembly. The seal tube assembly includes a seal tube, a seal, a first bearing, and a second bearing. The seal is coupled between the first and second bearings. The first bearing includes a flow path between the interior of the seal tube and the annular space between the seal and the seal tube. The SAP includes an SAP outer body positioned within the housing and fluidly sealed thereto. The RCD may include a running tool coupled to the SAP having one or more grippers for engaging a tool string passing through the RCD.

Abstract: A riser system and method including a bore submerged surface package of valves, a cross over assembly with a high pressure-low pressure connector connected to the bore submerged surface package of valves, a high pressure insert, and a telescoping flow tube. The riser system also include a high pressure bore subsea stack, a low pressure slip joint, a tension ring, a flex joint, a diverter, a mandrel capable of interfacing with the high pressure-low pressure connector, a high pressure mandrel crossover and at least one high pressure insert riser joint, a high pressure-low pressure latch, a telescoping flow tube telescopic conduit, at least one telescoping flow tube latch, a telescoping flow tube low pressure flex joint, a telescoping flow tube main housing, or a rotating control device.

Abstract: An offshore structure comprises: an original structure comprising a main platform supported via a foundation on a seabed; and an extension structure comprising a platform extension positioned laterally of the main platform and a platform extension support, depending downwardly from the platform extension, into contact with the foundation, so as to support the extension structure directly on the foundation.

Abstract: A wellbore intervention tool conveyance system includes an upper pipe injector disposed in a pressure tight housing. The upper injector has a seal element engageable with a wellbore intervention tool and disposed below the injector. The upper housing has a coupling at a lower longitudinal end. A lower pipe injector is disposed in a pressure tight housing, the lower housing has well closure elements disposed above the lower pipe injector. The lower housing is configured to be coupled at a lower longitudinal end to a subsea wellhead. The lower housing is configured to be coupled at an upper longitudinal end to at least one of (i) a spacer spool disposed between the upper pipe injector housing and the lower pipe injector housing, and (ii) the lower longitudinal end of the upper pipe injector housing.

Abstract: An installation (11) for drilling a well (13) into a soil comprising: —a discharge pipe (25) connected to the well (13) for recovering a drilling mud created by the drilling fluid mixing with components from the soil; —a flow rate sensor (92) to measure at least one parameter of the recovered drilling mud and generate a parameter value; —a calculator (94) connected to the flow rate sensor (92) to receive the parameter value in order to calculate a flow rate of the recovered drilling mud using the parameter value; characterized in that it further comprises a flume (90) having a throat and an approach channel hydraulically connected to the discharge pipe (25) to receive the recovered drilling mud, the measured parameter of the recovered drilling mud being representative of a height of the recovered drilling mud in the approach channel.

Abstract: What is provided is a method and apparatus wherein a swivel can be detachably connected to an annular blowout preventer thereby separating the drilling fluid or mud into upper and lower sections and allowing the fluid to be displaced in two stages, such as while the drill string is being rotated and/or reciprocated. In one embodiment the sleeve or housing can be rotatably and sealably connected to a mandrel. The swivel can be incorporated into a drill or well string and enabling string sections both above and below the sleeve to be rotated in relation to the sleeve. In one embodiment the drill or well string does not move in a longitudinal direction relative to the swivel. In one embodiment, the drill or well string does move longitudinally relative to the sleeve or housing of the swivel.

Abstract: Injection of gas into a managed pressure drilling system to provide for operation of the drilling system in a downhole pressure window defined by the pore pressure of a formation being drilled and a fracture pressure of the formation. Gas injection being controlled so as to produce the desired downhole pressure without causing large oscillations in borehole pressure.

Abstract: Disclosed herein are embodiments of an offshore drilling rig comprising a drill floor deck having a hole defining a first well center. Embodiments of the drilling rig further comprise a first mast upwardly extending relative to the drill floor deck, and a first hoisting system supported by the first mast and configured for hoisting and lowering tubular equipment through the first well center. The first mast is located on a first side of the first well center. Embodiments of the drilling rig further comprise first pipe handling equipment for presenting tubular equipment to the first hoisting system so as to allow the first hoisting system to hoist or lower the tubular equipment through the first well center.

Abstract: An apparatus and method for connecting an umbilical to a marine riser is provided. The method and apparatus can be employed in instances when a riser is already in place in the water, extending from a drilling vessel to subsea equipment on the ocean floor.

Abstract: A system for injecting fluids into a well having a fluid supply line that is connected to a mandrel at the top of the production tree. The system is designed so that all components of the system are packaged together and run to the production tree in one run. The production tree is designed to provide a pathway for the fluid to travel from the mandrel to the production bore within the tree, and then into the production tubing of a well.

Abstract: An adapter assembly having a sealing element, a drive bushing, and an adapter flange disposed between the sealing element and the drive bushing. Also, a method of assembling a rotational control device that includes coupling mechanically an adapter flange to a sealing element, coupling mechanically the adapter flange to a drive bushing, and installing the adapter flange, sealing element, and drive bushing in the rotational control device.

Abstract: A hydrocarbon drilling tubulars storage and handling system, said system comprising: —first and second rotary storage racks, each rotary storage rack being rotatable about a vertical axis and having storage slots for storage of multiple tubulars in each rotary storage rack in vertical orientation, the first and second rotary storage rack each including a drive to rotate the storage rack about its vertical axis, —a tubulars racking device positioned between the first and second rotary storage racks, said racking device including a rotary structure that is rotatable about a vertical axis and a drive to rotate the rotary column structure about said vertical axis, the rotary structure supporting at a first side thereof a first tubular racker assembly and at a second side thereof a second tubular racker assembly, each tubular racker assembly including one or more one gripping members adapted to grip a tubular.

Abstract: A method and a device for enabling the use of riserless drilling fluid recovery from a seabed-based borehole (1) which is to be drilled by means of a casing (26), the casing (26) being provided with a drill bit (28) at its lower portion and with an inner wellhead (30) at its upper portion, and there being a conductor casing (6), which has an outer wellhead (8), in the seabed (2), the method including: —providing a suction module (12) with a dividable adapter (16) which fits complementarily in the outer wellhead (8); —drilling a length of the borehole (1) by means of the casing (26) extending through the suction module (12), while, at the same time, drilling fluid is flowing via the suction module (12) from the borehole (1); —subsequently pulling the adapter (16) up from the outer wellhead (8) and dividing the adapter (16); and—lowering the casing (26) with the inner wellhead (30) through the suction module (12) and the adapter (16) to its position in the outer wellhead (8).

Abstract: Apparatuses and methods useable in drilling installations having a mud loop for detecting ongoing or imminent kick events are provided. An apparatus includes a first sensor configured to measure a input mud flow pumped into the well, and a second sensor configured to measure a variation of a return mud flow emerging from the well. The apparatus further includes a controller connected to the first sensor, and to the second sensor. The controller is configured to identify an ongoing or imminent kick event based on monitoring and comparing an evolution of the input mud flow as measured by the first sensor and an evolution of the return mud flow as inferred based on measurements received from the second sensor. Additionally, a third sensor can be included in the apparatus to confirm the conclusion made by the controller before alerting the user that a kick has likely occurred.

Abstract: What is provided is a method and apparatus wherein a rotating and reciprocating swivel can be detachably connected to an annular blowout preventer thereby separating the drilling fluid or mud into upper and lower sections with the mandrel of the swivel being comprised of double box end joints and using double pin end subs to connect a plurality of such mandrel joints together.

Abstract: Apparatuses useable in drilling installations for adjusting a mud return flow in a mud loop, at a location far from a mud tank are provided. An apparatus includes (1) a sensor located close to a seabed and configured to acquire values of at least one parameter related to a return mud flow, (2) a valve located near the sensor and configured to regulate the return mud flow, and (3) a controller connected to the valve and the sensor. The controller is configured to automatically control the valve to regulate the return mud flow towards achieving a value of a control parameter close to a predetermined value, based on the values acquired by the sensor. Methods of incorporating an apparatus in a drilling installation and retrofitting existing installations are also provided.

Abstract: A fingerboard latch assembly includes a latch configured for operational engagement with a fingerboard for lockingly retaining at least one tubular to the fingerboard. The latch is movable within a range of motion extending from at least a locked position to an unlocked position. A positioner operatively engaged with the latch is communicably couplable to a process control network (PCN), and is sized and shaped for receipt within a latch channel of the fingerboard. The positioner is configured to move the latch within the range of motion in response to signals received from the PCN, to capture position data for the latch, including the position of the latch at a plurality of points within the range of motion, and to communicate the captured position data to the PCN.

Abstract: The invention relates to an underwater drilling arrangement and a method for introducing a foundation element into a bed of a body of water comprising a submersible working platform for placement onto the bed of a body of water, several ground contact elements which are arranged in an adjustable manner on the working platform for aligning the working platform on the bed of a body of water, and at least one guide pipe for receiving and guiding the drilling tool. For an improved anchoring provision is made according to the invention for the guide pipe to be supported in a longitudinally displaceable and rotatable manner on the working platform and for a guide pipe drive to be provided on the working platform for driving the guide pipe in a rotating manner.

Abstract: A triple activity drilling ship may be provided with two separate drilling centers, each including drilling apparatus. In addition, a trolley that is capable of supporting tubulars may be positioned between a first position within one of said drilling centers and a second position outside that drilling center. As a result, the trolley may be used to hold assembled tubulars while other activities are ongoing in one or more of the drilling centers.

Abstract: A sealing arrangement and method for dynamic sealing around a drill stem (50) in water-carrying, drilling fluid-carrying or hydrocarbon-carrying wells, comprising at least one dynamic sealing (35a) which is arranged to envelop the drill stem (50), and a receiver unit (30) arranged to receive the at least one sealing (35a), with the dynamic sealing being arranged to be driven into the receiver unit (30) with the help of the drill stem, and to be securely locked in the receiver unit, and also that internal pressure support in the sealing arrangement is provided corresponding to at least the surrounding pressure.

Abstract: A drilling system (10) including a drill string (13) which extends from a floating drilling rig to a well bore, and a tubular riser (12) which surrounds at least part of the portion of the drill string (13) between the well bore and drilling rig, the riser (12) having a telescopic joint (20) between a first tubular portion and a second tubular portion of the riser, the first tubular portion extending down to a well head at the top of the well bore and the second tubular portion extending up towards the drilling rig, the telescopic joint (20) comprising an inner tube part (20b) which is mounted within an outer tube part (20a), the drilling system (10) further including a riser closure device (26) which is mounted in the second tubular portion of the riser (12) and which is operable to provide a substantially fluid tight seal between the riser (12) and the drill string (13) whilst permitting the drill string (13) to rotate relative to the riser (12).

Abstract: A method and device for establishing a borehole (26) in the seabed (4), comprising setting of a conductor (1), wherein the method is characterized in that it comprises:—providing the conductor (1) with a suction module (6);—then lowering the conductor (1) down to the seabed (4); and—displacing the conductor (1) down into the seabed (4).

Abstract: Provided is a damping apparatus for a moonpool, which has a simple driving mechanism. The damping apparatus includes one or more damping plates which cover a moonpool of a hull entirely or partially. The damping plates are pivotally hinged to a sidewall of the moonpool, and one or more conveying units are disposed above the moonpool to convey drilling equipment. Driving wires are coupled between the conveying units and the damping plates, and the conveying force of the conveying units is transferred through the driving wires to the damping plates. Thus, the damping plates are pivoted to open and close the moonpool entirely or partially.

Abstract: Various embodiments of underwater wellhead closure systems are described that include a template having first and second anchoring ports and that is configured to be secured to a floor of a body of water. A suction pile having a cylindrical body with a head portion and an open bottom can be coupled to the first anchoring port, such that the suction pile can provide additional hold down force to the template. The system can also include a suction cap coupled to the second anchoring port, and having a cylindrical body with an open bottom and a head portion having at least one suction pump.

Abstract: What is provided is a method and apparatus which can be detachably connected to an annular blowout preventer thereby separating the drilling fluid or mud into upper and lower sections and allowing the fluid to be displaced in two stages, such as while the drill string is being rotated and/or reciprocated. In one embodiment the sleeve can be rotatably and sealably connected to a mandrel. The swivel can be incorporated into a drill or well string and enabling string sections both above and below the sleeve to be rotated in relation to the sleeve. In one embodiment the drill or well string does not move in a longitudinal direction relative to the swivel. In one embodiment, the drill or well string does move longitudinally relative to the sleeve of the swivel.

Abstract: A triple activity drilling ship may be provided with two separate drilling centers, each including drilling apparatus. In addition, a trolley that is capable of supporting tubulars may be positioned between a first position within one of said drilling centers and a second position outside that drilling center. As a result, the trolley may be used to hold assembled tubulars while other activities are ongoing in one or more of the drilling centers.

Abstract: The invention relates to a device for manufacturing a foundation for a mass located at height, such as the jacket of a wind turbine or a jetty, wherein the foundation comprises a quantity of piles driven into an underwater bottom in a geometric pattern. The device comprises a positioning framework of a number of mutually connected guide tubes arranged in a geometric pattern and adapted to receive and guide a pile to be driven into the underwater bottom, wherein the guide tubes comprise a mechanism with which at least an internal wall part of the guide tubes is displaceable in the radial direction of the guide tubes from a radially inward support position for the pile to a radially more outward position in which the internal wall part substantially releases the pile. The invention also relates to a method and an assembly of a jack-up platform and the device.

Abstract: A method of drilling and producing from an offshore structure, comprising drilling a first well from the offshore structure with a drilling riser; completing the first well with a first subsurface tree; connecting the first subsurface tree to a manifold; drilling a second well from the offshore structure with a drilling riser; completing the second well with a second subsurface tree; connecting the second subsurface tree to the manifold; and connecting a production riser to the manifold and the offshore structure.

Abstract: The present invention relates to a managed pressure and/or temperature drilling system (300) and method. In one embodiment, a method for drilling a wellbore into a gas hydrates formation is disclosed. The method includes drilling the wellbore into the gas hydrates formation; returning gas hydrates cuttings to a surface of the wellbore and/or a drilling rig while controlling a temperature and/or a pressure of the cuttings to prevent or control disassociation of the hydrates cuttings.

Abstract: An offshore universal riser system may include a valve module which selectively permits and prevents fluid flow through a flow passage extending longitudinally through a riser string. An anchoring device may releasably secure the valve module in the passage. A method of constructing a riser system may include the steps of installing the valve module in the passage, and installing at least one annular seal module in the passage. The annular seal module may prevent fluid flow through an annular space between the riser string and a tubular string positioned in the passage. Drilling methods may include injecting relatively low density fluid compositions into the annular space, and selectively varying a restriction to flow through a subsea choke in a drilling fluid return line. The riser string, including housings for the various modules and external control systems, may be dimensioned for installation through a rotary table.

Abstract: A system compensates for heave-induced pressure fluctuations on a floating rig when a drill string or tubular is lifted off bottom and suspended on the rig, such as when tubular connections are made during NIPD, tripping, cementing operations or when a kick is circulated out during conventional drilling. In one embodiment, a pressure relief valve or adjustable choke allows the movement of fluid from the riser when the tubular moves down, and a pump with a pressure regulator moves fluid to the riser when the tubular moves up. The system also compensates for heave induced pressure fluctuations on a floating rig when a riser telescoping joint located below an RCD is moving between its retracted and extended positions while drilling.

Abstract: A subsea wellhead assembly comprising a casing housing and a casing extending down inside the well, and a tubing hanger. The tubing hanger comprises first and second valves, each valve being a fail safe valve.

Abstract: An accumulator for a subsea blowout preventer unit including a blowout preventer includes a body. The body includes a hydraulic fluid chamber and a gas chamber. The hydraulic fluid chamber has a smaller inner diameter than the gas chamber. The accumulator further includes a hydraulic fluid port in fluid communication between the hydraulic fluid chamber and the subsea blowout preventer, a hydraulic piston slidably and sealingly mounted in the hydraulic fluid chamber, and a charge piston slidably and sealingly mounted in the gas chamber. A pressure port receives pressure to provide a force on the opposite side of the charge piston from the hydraulic piston.

Abstract: A whipstock system for drilling a wellbore from a water bottom supported platform having wellbores with conductor pipes disposed through guide slots in a template on the bottom of a body of water includes a whipstock pipe extending from an equipment deck surface on the platform to a stab in sub. The whipstock pipe includes a window and j-slot mechanism for releasably engaging a scab liner. A stab in sub is configured to make mechanical connection between the whipstock pipe and a surface of a wellbore conductor pipe cut proximate the water bottom. The system includes a scab liner extending from the window to the water bottom when the stab in sub is engaged to the cut conductor pipe. The window is disposed above the water bottom. The scab liner configured to enable drilling a wellbore surface hole therethrough to a selected depth of a surface casing.

Abstract: The disclosure provides a method and system of installing subsea well trees, comprising: creating a glory hole having a depth below a seabed at a well location of a hydrocarbon reservoir; moving a floating offshore platform coupled with a foundation, the platform having a topsides and a caisson with downwardly extending walls defining an inner volume between the walls, the foundation coupled to the caisson walls, and the caisson walls having adjustable buoyancy; lowering the offshore platform with the foundation into the glory hole; drilling from the topsides into the hydrocarbon reservoir below the foundation to create a well; installing a well tree on the well, the well tree being disposed in the glory hole below the height of the seabed; coupling the well tree to a flow line; releasing the offshore platform from the foundation; and reusing the offshore platform to install other foundations at other predetermined well locations.

Abstract: A riser pipe for drilling an offshore well comprises a main tube extending the well up to a floating support, an auxiliary line being arranged parallel to main tube (4a, 4b). The auxiliary line comprises tubular sections (7a, 7b) made of steel and assembled end to end with a sliding fit by means of a tubular end part (25). According to the invention, a material, a titanium alloy for example, having an elastic limit at least 25% higher than that of the steel tubular sections (7a, 7b), is selected to manufacture said end part (25), and the end part as well as the end of said sections are dimensioned by taking account of the elastic limit of said material so as to reduce the sealing section of the end part.

Abstract: A fluid transfer device for use in wellbore drilling includes at least one pressure vessel having a fluid port at a bottom thereof for entry and discharge of a working fluid and a fluid port at a top thereof for entry and discharge of a power fluid. The pressure vessel has no physical barrier between the power fluid and the working fluid. Valves are coupled to the power fluid port for selective introduction of the power fluid into the at least one pressure vessel. Valves are coupled to the working fluid port such that the working fluid is constrained to flow in only one direction.

Abstract: An RCD is used to provide a system and method for sealing a marine riser having a rotatable tubular. A bypass internal channel or external line may be used to allow fluid to bypass the RCD seal. An RCD holding member seal could be a mechanically extrudable seal or a hydraulically expanded seal to seal the RCD with the riser.

Abstract: The invention relates to an underwater drilling arrangement and a method for making a bore in a bed of a lake, sea or river, having a service platform which can be lowered for positioning on the lake, sea or river bed, a guide tube which is mounted so that it can be rotated, axially moved as well as fixed on the service platform, a drill rod with drill head which is arranged in the guide tube and can be driven via a drill drive, and a guide tube drive which is arranged on the service platform for incorporation of the guide tube in the lake, sea or river bed. In order to reduce the friction which arises upon incorporation of the guide tube between the outer shell surface of the guide tube and the earth material of the lake, sea or river bed, the guide tube has a sliding support means.

Abstract: A system including a setback and racking system and a set of wellbay accesses, at least a portion of the setback and racking system positioned at an elevation lower than the elevation of the wellbay accesses. A system including a centrally located setback and racking system, a set of wellbay accesses, and at least one peripheral skidding system, wherein the setback and racking system is positioned at least partially below the elevation of the peripheral skidding system. A system including at least one peripheral skidding system and a set of wellbay accesses positioned along a wellbay access perimeter surrounding a central focus that is not an integral part of the peripheral skidding system. A method of drilling by aligning each of at least two drilling modules with a respective wellbay access via a peripheral skidding system and operating at least two drilling modules at least partially simultaneously.