The invention relates to a modular riser section storage and handling system for storing and handling riser sections which riser sections are adapted to be used in offshore wellbore drilling activities. The invention further relates to a method for using such a modular riser section storage and handling system and a vessel comprising such a modular riser section storage and handling system.

Offshore wellbore drilling comprises placing a subsea template on a seabed, said subsea template may be a concrete slab with a hole that marks the wellbore. A riser may be placed between the subsea template and a drilling vessel. The riser functions to protect the wellbore drill, allow mud and other residue to be carried off, and to allow subterranean gas or oil to be transported from the wellbore to the vessel. The riser is constructed from riser sections.

Commonly a riser section comprises a riser pipe and additionally one or more auxiliary pipes, also called satellite, service, or peripheral pipes or lines, on the outside of and parallel along the riser pipe. The auxiliary pipes are e.g. used as fluid lines, e.g. to a BOP or other subsea equipment, as choke line, kill line, hydraulic line, booster line, injection line (e.g. for glycol), etc.

In a common design the main riser pipe is provided at each end thereof with a radially extending flange, the main pipe and the flanges being made of steel. One or both of the flanges may have bolt holes allowing to join riser sections by means of bolts and nuts.

An auxiliary pipe may have an individual connector fitting at its end or ends, e.g. a bayonet fitting, or be designed to fit sealingly into the auxiliary pipe of an adjoining riser section.

Riser sections come in different lengths. Commonly riser sections have lengths between 50 ft. (15.24 meters) and 90 ft. (27.43 meters). A very common length for riser sections is 75 ft. (22.86 meters).

Riser sections are commonly heavy; far heavier than other tubulars used in the offshore drilling industry. For example a single 75 ft. subsea riser section may weigh between 20 and 25 tonnes, which is incomparable to the weight of an equally long drill pipe. Therefore riser handling is subject to different considerations than drill pipe handling, mainly in view of their size (diameter) and weight.

The riser sections typically are wide enough to facilitate the wellbore drill and allow passage of drilling residue, oil and/or gas. The riser sections are typically provided with floating devices to enable the vessel to support the riser in the upright position. In order to compensate for heave motion, typically one or more of the riser sections are telescopic riser sections. During transport to the drilling location, the riser sections are stored on the deck of the drilling vessel.

Patent publication US 4,202,653 discloses a riser section storage and handling system including an overhead crane, supported on an overhead track, multiple type of rack bins comprising riser sections and drill pipe, and a riser section handling station for moving the riser in an axial direction towards and away from the rack bins. The disclosed system is configured for storing and moving small diameter drill pipe, larger diameter casing pipe and still larger diameter riser pipe. The some of the rack bins comprise guide channels for stacking riser sections. The rack bins are fixed to the deck of the vessel. The deck thus forms part of the frame that provides the rack bins with structural integrity. The overhead track is supported on vertical support beams, which vertical support beams are located outside the rack bins and are fixed to the deck of the vessel.

Patent publication WO 2018/172529 A1 discloses a method for providing a deck surface on an offshore drilling rig comprising installing a modular deck structure comprising a plurality of deck modules over at least a portion of a vertical riser storage bay provided for storing riser joints in a vertical orientation. In one disclosed example, the modular deck structure is mounted on existing infrastructure within the riser storage bay.

Patent publication EP 0174055 discloses an arrangement for storing pipes in an offshore drilling installation below an upper deck carrying a derrick with associated equipment comprising a pipe magazine below the upper deck, a horizontal transport means for the individual displacement of riser sections between an aperture in the upper deck and storage means formed by a plurality of racks.

The number of riser sections that are necessary for any wellbore drilling operation depends on the depth of the sea. For example, in the North Sea the depth of the sea is typically a few dozen meters and few riser sections are needed, whereas off the coast of Brazil the sea may be much deeper and many riser sections are needed. Riser section storage on a vessel is typically designed to allow storage of the number of risers needed for the deepest sea in which the vessel is intended to be used. A riser section storage adapted for storing a high number of riser sections thus costs a lot of valuable deck space. Deck space is valuable because deck space is a limited commodity, and is used to store many equipment and utilities. Therefore, area of the deck space occupied with riser section storage is preferably kept to a minimum. To minimise loss of valuable deck space, vessels are preferably used in seas with depths close to the maximum depth for which the vessel was designed. For example, when a vessel designed for use in deep sea is used in the relatively shallow North Sea a lot of deck space is occupied with empty riser storage. This deck space thus cannot be used for other ends and effectively represents a loss of money. Hence, this vessel is preferably not used in the North Sea.

Loading and unloading of riser sections may be a time consuming process and is preferably done as time efficient as possible. This is particularly true when a lot of riser sections have to be loaded or unloaded from the deck of a vessel, as may be the case when the wellbore is located in deeper sea. Loading riser sections on the vessel costs time in which the vessel is not used in a drilling operation, thus the owner of the vessel may be losing profit.

It is an object of the invention to provide an improved riser section storage and handling system. In particular, to provide a more versatile riser section storage and handling system which allows for more efficient use of deck space of the vessel. It is a further object of the invention to provide a riser section storage and handling system that allows for more efficient loading and unloading of the riser sections to and from the vessel.

The invention therefore provides a modular riser storage and handling system according to claim 1.

According to the invention, the modular riser section storage and handling system is configured to be mounted on a deck of an offshore drilling vessel for storing and handling riser sections for use in offshore wellbore drilling activities, and is configured to be lifted from the deck of the vessel to free deck space, the system comprising:

- multiple riser section transport containers for transporting multiple riser sections from a shore to the deck of the offshore drilling vessel, each adapted for storing multiple riser sections and each having a top entry opening for lifting and lowering the riser sections in and out of the transport container, wherein the transport containers are configured to be set up side to side in a storage configuration on the deck of the vessel, wherein the riser section transport containers each have a longitudinal axis extending from one end of the transport container to an opposite end of the transport container, and wherein the top entry opening extends parallel to the longitudinal axis between the opposite ends of the container, and wherein the top entry opening of the transport containers has a length larger than the length of the riser sections to be held in the transport container, to enable the riser sections to be lifted in and lowered in a lateral the direction, i.e. substantially perpendicular to a longitudinal axis of the riser section, through the top entry opening, and to enable the riser sections to be stored in a horizontal direction by the container in the storage configuration,

- a riser section handling station, adapted for handling riser sections, e.g. transport a riser in a horizontal direction into or out of the handling station, which handling station is configured to be set up side to side with one or two of the multiple riser section transport containers in the storage configuration;

- an overhead crane adapted for lifting and lowering riser sections in the lateral direction in and out of transport container and an overhead crane control device for controlling the movement of the overhead crane; and

- an overhead track, comprising multiple track sections, which overhead track is configured to moveably support the overhead crane; wherein the multiple riser section transport containers, and preferably the riser section handling station, are configured to support at each end of the transport container, between the top entry opening and the ends of the transport container the overhead track when in the storage configuration, to enable the overhead crane to travel above and along the multiple transport containers in the storage configuration and to move riser sections between the multiple transport containers and the riser section handling station.

The riser storage and handling system according to claim 1 comprises multiple riser section transport containers that are configured to be set up side to side in a storage configuration, and an overhead track for supporting the overhead crane. The multiple riser section transport containers set up in the storage configuration support the overhead track, and thus enable the overhead crane to travel above and along the multiple transport containers in the storage configuration and to move riser sections between the multiple transport containers and the riser section handling station. The multiple transport containers in combination with an overhead track comprising track sections enables a modular set up of the modular riser section storage handling system. Simply by providing more or less transport containers and a track composed of more or less track sections respectively allows for a modular riser section handling system having a large or small storage capacity and footprint.

Furthermore, providing transport containers for holding the riser sections facilitates transport of the riser sections, and also allows for transporting multiple riser sections at once, i.e. in one container that speeds up the transport. Utilising the transport containers for supporting the overhead track allows for an efficient set up, demounting, and adaptation of the modular riser section storage and handling system.

The multiple riser section transport containers in combination with the overhead track comprising multiple track sections thus allow for a versatile riser section storage system. Depending on the number of riser sections that have to be stored on the deck of the vessel, one or more of the multiple riser section transport containers may be mounted on the deck of the vessel.

For example, if the vessel is to be moved to shallow waters, one or more of the transport containers may be lifted from the deck of the vessel creating free deck space. The freed up deck space may be used for other purposes such as storage of a well template.

On the other hand, if more riser section storage capacity is needed more riser section transport containers may be placed on the deck of the vessel. Hence, the size of the footprint of the riser section storage system on the deck of the vessel is flexible and may be adjusted based on the number of riser sections needed in a particular well drilling operation. The full modular riser section storage and handling system including the overhead crane and riser handling station may be lifted from the deck of the vessel completely freeing the deck of the vessel for other use and other purposes. Hence, the system allows for more versatile use of the deck space of the vessel.

The invention can be used with riser sections having lengths between 50 ft. (15.24 meters) and 90 ft. (27.43 meters), a very common length for riser sections is 75 ft. (22.86 meters), but may also be used with risers sections of great length, for example riser sections of at least 100 ft. (30.48 m), e.g. of 120 ft. (36.57 m) or 150 ft. (45.72 m). Riser sections are typically provided with buoyancy means, due to which they have a comparatively large diameter compared to drilling tubulars. Riser sections may be placed in the riser section transport containers while the riser section transport containers are still on a shore and while the vessel is not yet ready to receive the riser sections. Placing the riser section transport containers containing the riser sections on the deck of the vessel allows for multiple riser sections to be loaded on the deck of the vessel at once. The riser sections may also be removed from the vessel using the riser section transport containers. This speeds up the process of loading and unloading of riser sections, increasing the efficiency of the loading and unloading process.

The invention comprises an overhead crane which is adapted to move along the overhead track for lifting and transporting riser sections, and which overhead crane can be removed from and can be placed on overhead track.

The overhead track for use by the overhead crane is formed by track sections that are located preferably on top of the riser section transport containers. Removal of riser section transport containers removes all or some track sections that form the overhead track. The length of the overhead track is thus flexible. Hence, the invention allows for easy removal of the track, or sections thereof and the overhead crane, thus further increasing the versatility of the modular riser section storage and handling system. The deck space occupied by the riser section handling system, embodied by the transport containers, the overhead crane and the overhead track, can thus be optimised for different well bore drilling operations depending on the number of riser sections needed.

Each track section may comprise two tracks components, which track components placed on opposite ends of the respective riser section transport container. In an embodiment, the track components are single beams. This allows for efficient support of the overhead crane. The track may also comprise rollers or a pinion structure for supporting the overhead crane and allowing the overhead crane to move along the track.

In an embodiment, the riser section transport containers each have a longitudinal axis extending from one end of the transport container to an opposite end of the transport container, and the top entry opening extends parallel to the longitudinal axis between the opposite ends of the container. The container is configured to support at each end of the transport container, between the top entry opening and the ends of the transport container, a track section, the track sections extending parallel to each other and in a direction

perpendicular to the longitudinal axis of the transport container. Preferably, the riser section transport container is a longitudinal container, having a longitudinal axis that extends between opposite ends of the container, and comprises a reinforced frame at each end and at opposite sides of the top entry opening of the container, which reinforced frames enable the container to support the track sections, and the overhead crane moving along that track section while supporting a riser section, and to transfer that load to the deck of the vessel.

In a further embodiment, the reinforced frames comprise connector devices for securing the transport containers to each other in the storage configuration and/or securing devices for securing the transport container to mounts in or on the deck of the vessel.

In a further embodiment, or as an alternative, the reinforced frames comprise stacking frames, wherein said stacking frames are provided with stacking devices for supporting a stack of riser sections, for example three riser sections, one above the other.

In an embodiment, the multiple riser section transport containers, and preferably the riser section handling station, each comprise a track section, preferably on a top side of transport containers, preferably each track section comprising two track components located on opposite sides of the entry opening, such that when the transport containers are set up in the storage configuration the track sections form the overhead crane transport track. In such an embodiment, the track sections are part of the transport container and preferably of the handling station. Thus, by positioning the transport containers and the handling station in the storage configuration, the track is set up.

In an alternative embodiment, the track sections are mounted on the transport containers, and preferably, the handling station, to compose the overhead track after the transport containers and the handling station are set up in the storage configuration. In such an embodiment, track sections, more in particular the components such as rails or beams making up the track sections, can be transported separately from the transport containers. Furthermore, in such an embodiment a single track section may extend from one transport container to another, may even extend over multiple containers, and thus bridge the area where two adjacent containers meat up. Such a configuration allows for single track sections, and may thus enable a continuous track with only a limited number of transitions between track sections.

In a further embodiment, the track sections may be configured to as connector devices for connecting adjacent riser section transport containers, and preferably the riser section handling station, when the multiple riser section transport containers, to thus secure the transport containers in the storage configuration.

The track sections may be integrated in the frame of the transport container or they may be placed separately on the top side of the riser section transport container.

The riser section handling station is adapted for handling riser sections and may receive riser sections from the overhead crane and prepare the riser sections for transport, preferably in an axial direction i.e. parallel to a longitudinal axis of the riser section, to a firing line of a well bore drilling operation on the deck of the vessel. The riser sections may be transported to the riser section handling station by the overhead crane through for example a top side of the riser section handling station and further moved towards the firing line through an end or side of the riser section handling station. Riser sections may also be transported from the firing line through the riser section handling station to a riser section transport container.

When the multiple riser section transport containers and the riser section handling station are placed on the deck of the vessel in the storage configuration, they are placed adjacent to each other on the deck of the vessel. The riser section handling station may be located on an end of the modular riser section storage and handling system where a riser section transport container is only adjacent to one side, or the riser section handling station may be located in the modular riser section storage and handling system with riser section transport containers adjacent on two sides of the riser section handling system. The most efficient configuration of the riser section transport containers and the riser handling station depends, among other things, on the side through which riser sections are transported from the riser section handling station.

Thus, the invention allows for a riser section storage and handling system having a versatile deck space footprint, which allows for a more efficient use of the deck of the vessel.

Furthermore, the riser section handling system allows for a more efficient loading and unloading of riser sections on the vessel. This may reduce total time and cost of well bore drilling operations.

In an embodiment, the multiple riser section transport containers, and preferably the riser section handling station, each comprise a track section, preferably on a top side of transport containers and preferably on opposite sides of the entry opening, such that when the transport containers are set up in the storage configuration the track sections form the overhead crane transport track. Thus, in an embodiment, the track section comprises two parallel components, e.g. rails or skid beams, said parallel tracks being provided on opposite sides of the top entry opening, and extending parallel to each other. Thus, the overhead crane is supported on opposite sides of the top entry opening.

In an embodiment, each one of the multiple riser section transport containers comprises a storage space enclosed by a bottom side, a first side, a second side, a first end a second end and a top side of the container. The container preferably has a longitudinal axis that extends from the first end to the second end. The storage space is dimensioned to hold one or more riser sections, preferably such that the riser sections extend in a direction parallel to the longitudinal axis of the container.

The top entry opening of the transport containers has a length larger than the length of the riser sections to be held in the transport container, to enable the riser sections to be lifted in and lowered in a lateral the direction, i.e. substantially perpendicular to a longitudinal axis of the riser section, through said opening, and to enable the riser sections to be stored in a horizontal direction by the container in the storage configuration.

In an embodiment, the riser section transport containers each comprise stacking frames, wherein said stacking frames are provided with stacking devices for supporting a stack of riser sections, for example three riser sections, one above the other in the transport container. This way of stacking riser sections in the riser section transport container allows for efficient storing and removal of the riser sections in the containers.

In an embodiment, the multiple riser section transport containers, and the riser section handling station, comprise connector devices for connecting adjacent riser section transport containers, and preferably the riser section handling station, when the multiple riser section transport containers and the riser section handling station are set up in the storage

configuration on the deck of the vessel.

Connecting adjacent riser section transport containers, and preferably the riser section handling station in the storage configuration, allows for a rigid and preferably stronger meta structure of the modular riser section storage and handling system when it is located on the deck of the vessel. A rigid meta structure is advantageous since it allows for solid base for the overhead track.

The connectors may comprise clamps that clamp onto clamp receivers on adjacent riser section transport containers or the riser section handling station. Such clamps preferably comprise a locking mechanism for locking the clamps into a locked position. Preferably, the connectors are locked before the vessel moves towards a wellbore drilling site.

In an embodiment, the connector devices are embodied as track section links, which track section links are configured to bridge a gap between the track sections of two adjacent riser section transport containers, to provide a substantially continuous, preferably bump free, connection between two track sections, more in particular between the track sections of two adjacent transport containers.

In an embodiment, riser section transport containers, and preferably the riser section handling station, are adapted to be located on a deck, preferably are provided with securing devices for securing the transport containers, in the storage configuration, to mounts on the deck of the vessel, which securing devices preferably are provided on stacking frames of the transport containers.

As the vessel moves through a sea it may be subject to various motions due to the sea acting on the vessel. An example of such a motion is heave motion. To prevent the modular riser section storage and handling system from moving over the deck of the vessel it may be advantageous to secure the riser section transport containers and the riser section handling station to the deck of the vessel. Said securing devices and mounts may comprise clamps and clamp receivers. The clamps connect to the clamp receivers. For example, the clamps may be located on the deck of the vessel and the clamp receivers may be located on or near the bottom side of the riser section transport containers and the riser section handling station. Preferably, the securing devices may also comprise a locking mechanism for locking the securing devices in a locked position.

Preferably, the multiple transport containers, and preferably the riser handling station, are secured to each other, thus forming a meta structure, which meta structure is mounted to the deck of the vessel. Thus, it may not be necessary to mount each of the transport containers and the handling station to the deck individually.

In an embodiment, the transport containers are provided with transport devices, for example eyes, for coupling a crane to the transport containers for lifting the transport containers comprising riser sections. Thus, the transport of the containers by crane, and thus for example the transfer between ships, is facilitated.

In an embodiment the track sections comprise track section links, configured to bridge a gap between the track sections of two adjacent riser section transport containers, to provide a substantially continuous, preferably bump free, connection between the two track sections, for example, at one end hingeably connected to a riser section transport container to be pivoted from a retracted position into an extended position, in which it engages the track section of an adjacent riser section transport container.

As the transport containers are set up next to each other, gabs may remain between the containers. As the overhead crane moves over the track it encounters places where track sections meet. These places possibly have gaps in the track making the movement of the overhead crane over these gaps less smooth. Advantageously the movement of the overhead crane is as smooth as possible.

In an embodiment, the transport containers comprise track sections, said track sections comprising track components such as rails or skid beams, which track components extend beyond the contour of the transport container. The track components, more in particular an end or ends of the track component, may thus engage and/or be adjacent to an end of the track component of an adjacent transport container.

In addition, or as an alternative, track sections mounted on the transport containers each comprise track section links, configured to bridge a gap between the track sections of two adjacent riser section transport containers, to provide a substantially continuous, preferably bump free connection between the two track sections, for example, at one end hingeably connected to a riser section transport container to be pivoted from a retracted position into an extended position, in which it engages the track section of an adjacent riser section transport container.

The track section links, configured to bridge a gap between the track sections of two adjacent riser section transport containers, make the movement of the overhead smoother, i.e. more bump free. This allows for saver and easier transport of riser sections.

The track section links may be at one end hingeably connected to a riser section transport container to be pivoted from a retracted position into an extended position. In the extended position the track section links engage the track section of an adjacent riser section transport container. In another embodiment, the track section links may be provided at an end of a track section, more in particular at the end of a track section component, where they are hingeably provided. In another embodiment, the track sections comprise track section links that slide to connect adjacent track sections. In an embodiment, the system further comprises stops to be provided at each end of the track, which stops, when the multiple riser section transport containers and riser section handling station are placed on the deck of the vessel in the storage configuration, are provided at an end of the overhead track to stop the overhead crane when the overhead crane reaches the end of the track.

For example, the stop may be a block provided on the track and/or comprise sensors or similar devices that signal the control system to stop movement of the overhead crane as it approaches the end of the track. Preferably, the overhead crane is prevented by the block from moving over an end of the track and falling off the track. The stop may be provided on special end track sections or it may be a separate stop which needs to be connected to the track after the multiple riser section transport containers and riser section handling station are placed on the deck of the vessel.

In an embodiment, a control system is provided which control system controls the overhead crane control device based on a supply of riser sections in the riser section transport containers and a demand of riser sections needed for the wellbore activities. Said control system may comprise a computer system which determines when riser sections have to be moved from the riser section transport containers to the riser section handling station or vice versa. The control system may be optimized for maximizing uptime of the wellbore drilling operation. The control system may further determine if sufficient riser sections are present or if more riser sections are necessary.

In an embodiment, the riser section handling station comprises a cart for transporting the riser sections from the modular riser section storage and handling system to the firing line of a wellbore drilling operation. Wherein the deck of the vessel comprises a cart track for allowing the cart to move between the riser section handling station and the wellbore drilling tower.

In an embodiment, the riser section handling station is configured to cooperate with a catwalk device, or for example a cart of the cat walk device.

Riser sections may be transported from the riser section handling station towards the firing line of the drilling tower. Advantageously this is done using a cart that moves on a cart track towards the firing line. The cart may have similar dimensions as a riser section, to provide stable transport of the riser section. The cart may also have a dimension smaller than a dimension of a riser section. A dimension of the cart may also be larger than a dimension of the riser section. Preferably, the cart comprises a drive for driving the cart automatically over the cart track towards the firing line. The cart may be controlled by the same control device that also controls the movement of the overhead crane.

In an embodiment and the riser section handling station is configured to cooperate with a cart track provided on the deck of the vessel for allowing the cart to move between the riser section handling station and the drilling tower.

In an embodiment, the riser section transport containers are further adapted to store telescopic tubulars. The telescopic tubulars may be provided in the riser to allow the riser to compensate for heave motion of the vessel. Such telescopic tubulars are advantageously stored and handled by the modular riser section storage and handling system since they typically have similar dimension as the riser sections. The telescopic tubulars may be stored with riser sections in a riser section transport container or they may be stored in a separate riser section transport container.

The overhead crane is adapted for lifting riser sections. Advantageously the overhead crane comprises grippers for gripping a riser section, preferably at or near opposite ends of the riser section. This provides for a stable grip on the riser section. Preferably, the overhead crane comprises two grippers. Preferably, the overhead crane is configures such that the grippers are provided near the track when they are in a position for supporting a riser section during transport along the track. This allows for more stable transport of the riser sections. The overhead crane may also comprise more grippers, for example a third gripper that is provided between the first two grippers on the overhead crane.

In an embodiment the riser sections are stored in a position parallel to the bottom side of a riser section transport container. In this embodiment, the riser sections are stored in a horizontal position when the riser section transport container is located on the deck of the vessel. This allows for a lower centre of gravity that advantageously gives a more stable riser storage and handling system on the deck of the vessel compared to an embodiment where the riser sections are placed vertically on the deck of the vessel.

The invention further relates to a method for storing and handling riser sections using a modular riser section storage and handling system according to the embodiments described above, wherein the method comprises the steps of:

- storing riser sections for use in wellbore drilling activities in riser section transport containers, wherein each one of the multiple riser section transport containers comprises an overhead track section which overhead track section is located on the top side of the respective riser section transport container;

- placing a riser section handling station, adapted for handling riser section, on the deck of a vessel, wherein the riser section handling station comprises an overhead track section which overhead track section is located on a top side of the riser section handling station;

- placing the multiple riser section storage transport containers, preferably at least three riser section transport containers, adjacent to each other and/or to the riser section handling station in the storage configuration on the deck of the vessel, wherein the track sections of the riser section transport containers and the track section of the riser section handling station form an overhead track;

- placing an overhead crane adapted for lifting riser sections on the overhead track;

- moving the vessel to a wellbore drilling location; and

- using the overhead crane to lift riser sections from the riser section transport containers and transporting the riser sections to the riser section handling station for use in wellbore drilling activities.

In an embodiment of the method, the method further comprises the step of connecting with each other adjacent riser section transport containers that are placed on the deck of the vessel and the riser section handling station with connector devices.

In an embodiment of the method, the method further comprises the step of securing the multiple riser section transport containers and the riser section handling station to the deck of the vessel using securing devices.

In an embodiment of the method, the method further comprises the step of bridging a gap between the track sections of adjacent riser section transport containers using track section links, to provide a substantially continuous, preferably bump free, connection between the two track sections, for example, at one end hingeably connected to a riser section transport container to be pivoted from a retracted position into an extended position, in which it engages the track section of an adjacent riser section transport container.

In an embodiment of the method, the method further comprises the step of providing stops to an end of the overhead track for stopping the overhead crane when the overhead crane reaches the end of the track. In an embodiment of the method, the method further comprises the step of controlling the overhead crane using a control system based on supply of riser sections in the riser section transport containers and demand of riser sections for the wellbore activities.

In an embodiment of the method, the method further comprises the step of transporting the riser sections from the modular riser section storage and handling system to a wellbore using a cart which cart moves along the deck of the vessel on a cart track between the riser section handling station and a drilling tower.

In an embodiment of the method, the method further comprises the step of storing telescopic tubulars in the riser section transport containers.

In an embodiment of the method, the riser sections are stored in a position parallel to the bottom of a riser section transport container.

The invention further relates to a vessel adapted for supporting a modular riser section storage and handling system according to the embodiments described above and for use of a method according to the embodiments of the method described above.

The invention further provides an offshore drilling vessel comprising a deck mounted modular riser section storage and handling system according to one of the embodiments described above and preferably for use of a method according to one of the embodiments of the method described above.

The invention furthermore relates to a use of an offshore drilling vessel as described above, for performing drilling activities, preferably for performing a method as described above.

It is submitted that riser sections typically have a diameter larger than drilling tubulars, and are provided with buoyancy means, which further increase the diameter of the riser sections compared to drilling tubulars or casing tubulars.

It is noted that the riser section transport containers of a modular riser may be configured to hold other types of tubulars as well, i.e. to hold for example drilling tubulars in addition to riser sections. Furthermore, the modular riser section storage and handling system may comprise, in addition to the multiple riser section transport containers, tubular section transport containers configured to store tubulars different from riser sections, for example drilling tubulars, which tubular section transport containers are configured to be set up adjacent to the riser section transport containers and/or the riser section handling station in the storage configuration, to enable the overhead crane to also transport tubulars between the tubular section transport containers and the riser section handling station. Thus, a more versatile modular riser section storage and handling system is provided, that in addition to riser sections may also store and handle other types of tubulars.

In an embodiment, the riser section handling station is configured to also store one or more tubulars, preferably store one or more riser sections.

The invention furthermore provides a method for providing multiple riser section transport containers and a riser section handling station in a storage configuration according to the invention on a deck of a vessel, the method comprising:

- setting up the riser section handling station on the deck of the vessel, preferably relative to a cart track provided in the deck of the vessel to enable a cart on said cart track to receive a riser section from the riser section handling station; and

- setting up a riser section transport container adjacent to the riser section handling station, preferably connecting the transport container to the riser section handling station;

- setting up a riser section transport container adjacent to the riser section transport container, preferably connecting the transport container to the transport container, and repeating this step until multiple transport containers are set up next to each other.

Advantageous embodiments of the modular riser section storage and handling system according to the invention and the method according to the invention are disclosed in the sub claims and in the description, in which the invention is further illustrated and elucidated on the basis of a number of exemplary embodiments, of which some are shown in the schematic drawing. In the figures, components corresponding in terms or construction and/or function are provided with the same reference numbers.

Fig. 1 shows a top view of an embodiment of a modular riser section storage and handling system;

Fig. 2 shows a side view of the modular riser section storage and handling system of figure 1 ; Fig. 3 shows a front view of the modular riser section storage and handling system of figure 1 ; and

Fig. 4 shows a front view of an empty modular riser section storage and handling system.

Whilst primarily presented for illustrative purposes with reference to one or more of the figures, any of the technical features addressed below may be combined with any of the independent claims of this application either alone or in any other technically possible combination with one or more other technical features.

Fig. 1 shows a top view of an embodiment of a modular riser section storage and handling system, adapted for storing and handling riser sections for use in wellbore drilling activities, 1 according to the invention. The riser section storage and handling system comprises multiple riser section transport containers 3, a riser section handling station 5, an overhead crane 4 with an overhead crane control device for controlling the movement of the overhead crane, and an overhead track 15.

In this embodiment four riser section transport containers 3 are placed adjacent to each other on the deck 12 of a vessel, and the riser section handling station 5 is located adjacent to the riser section transport containers 3. The multiple riser section transport containers 3 and the riser section handling station are set up side to side in a storage configuration.

Additional riser section transport containers 3 may be placed on the deck 12 of the vessel adjacent to the riser section transport containers 3.

The riser section transport containers 3 are adapted for storing multiple riser sections 2 and each have a top entry opening 13 for lifting and lowering the riser sections 2 in and out of the transport container 3.

The riser section handling station 5 is adapted for handling riser sections 2. The handling station 5 is set up side to side with the multiple riser section transport containers 3 in the storage configuration.

The overhead crane 4, for lifting and lowering riser sections 2, is supported by the overhead track 15. The overhead track 15 comprises multiple track sections 6, and is configured to moveably support the overhead crane 4.

According to the invention, the multiple riser section transport containers 3, and in the embodiment shown the riser section handling station 5, in the storage configuration support the overhead track 15 to enable the overhead crane 4 to travel above and along the multiple transport containers 3 in the storage configuration and to move riser sections 2 between the multiple transport containers 3 and the riser section handling station 5. Thus, the multiple transport containers 3 and the handling station 5 provide the track sections 6 that in combination form the overhead track 15. This configuration enables a modular set up of the modular riser section storage handling system. Simply by providing more or less transport containers and an overhead track composed of more or less track sections a modular riser section handling system having a large or small footprint, and a large or small storage capacity, is provided.

In the embodiment shown, the multiple riser section transport containers 3 and the riser section handling station 5 each comprise a track section 6 on a top side thereof, and preferably on opposite sides of the entry opening of the transport containers. Fig. 1 shows that when the transport containers 3 are set up in the storage configuration the track sections 6 form the overhead crane transport track 15. In the embodiment shown the track sections are supported at opposite ends of the respective transport containers and the handling station.

The riser section transport containers each have a longitudinal axis extending from one end of the transport container to an opposite end of the transport container. The top entry opening extends parallel to the longitudinal axis between the opposite ends of the container. The containers support at each end of the transport container, between the top entry opening and the ends of the transport container, the track section. At each end of the transport container is provided a track component 16, such that two track components make up the track section 6.

According to the claimed invention, each track section may comprise track components, for example in the embodiment shown two track components placed on opposite ends of the riser section transport container. The track sections 6, more in particular the track

components 16 of the track sections 6, extend parallel to each other and in a direction perpendicular to the longitudinal axis each of the transport containers 3.

Riser sections 2 are stored in the riser section transport containers 3. In the embodiment shown the transport containers are configured to store three stacks of 5 riser sections.

Depending on the size or type of riser section, the transport containers may be configured to hold a different number of riser section. For example, a transport container may be configured to hold a stack of two large diameter buoyancy member riser sections. Although the transport containers may differ in the size and number of riser sections to hold, the transport containers of a modular riser storage and handling system do have the same length and height, to enable the containers to fit in the storage configuration. In this embodiment, the riser sections 2 are distributed among twelve stacks that are evenly distributed among the four riser section transport containers 3. As mentioned above, the riser sections 2 may also be distributed among less or more than three stacks per riser section transport container 3, for example two stacks or four stacks. Riser section transport containers 3 may also have empty places where no stacks of riser sections 2 are present.

In the embodiment shown, each one of the multiple riser section transport containers 3 comprises a storage space enclosed by a bottom side 17, a first side 18, a second side 19, a first end 20 a second end 21 and a top side of the container.

The riser section transport containers are elongated containers, having a longitudinal axis that extends between opposite ends of the container in the embodiment shown, the transport containers comprise a reinforced frame at each end of the container, and at opposite sides of the top entry opening of the container, which reinforced frames enable the container to support the track sections, and the overhead crane moving along that track section while supporting a riser section. The reinforced frames transfer that load to the deck of the vessel.

The riser section transport containers 3 each comprise stacking frames 10. In the

embodiment shown, the reinforced frames are an integral component of the reinforced frames The stacking frames 10 are provided with stacking devices for supporting a stack of riser sections 2, for example three riser sections 2, one above the other.

On the top side of the riser section transport containers 3 and the riser section handling station the track sections 6 are located. The track sections 6 form the overhead track. The overhead crane 4 is located on top of the overhead track 6. The overhead crane is moveable along the overhead track. It can be used to transport the riser sections between the riser section handling station 5 and the riser section transport containers 3.

A cart 7 is located in the riser section handling station 5 on a cart track 8. The cart 7 can transport riser sections from the riser section handling station 5 along the cart track 8 towards a firing line of a well drilling operation. In this embodiment, the cart 7 has a dimension smaller than a dimension of the riser sections 2. In other embodiments the cart 7 may have a dimension larger or equal to a dimension of the riser sections 2. The cart 7 may comprise devices for securing a riser section 2 to said cart 7. In the embodiment shown, the overhead crane 4 comprises two grippers 11 which can grip a riser section 2 on two ends and lift the riser section 2 from its position in the riser section transport container 3. The riser section 2 may be transported by the overhead crane 4 to the riser section handling station 5 where it may be placed on the cart 7 for transport away from the riser section storage and handling system 1. A riser section 2 may also be delivered to the riser section handling station 5 by the cart 7. The riser section 2 can then be lifted from the cart 7 by the overhead crane 4 and be transported to a riser section transport container 3.

Adjacent riser section transport containers 3 and the riser section handling station 5 may be connected to each other through connector devices. In addition, the riser section transport containers 3 and the riser section handling station 5 may comprise securing devices for securing the riser section transport containers 3 and the riser section handling station 5 to the deck 12 of the vessel.

The track sections 6 comprise track section links 9, configured to bridge a gap between track sections 6 of two adjacent riser section transport containers 3. The track section links 9 may provide a substantially bump free connection between the two track sections 6.

Fig. 2 shows a side view of the modular riser section storage and handling system 1 of figure 1. The modular riser section storage and handling system 1 is placed on the deck 12 of a vessel. The riser sections 2 are stored in stacks wherein each stack comprises five riser sections 2. In figure 2 the modular riser section storage and handling system 1 is full with riser sections. The stacks are separated by the box like frame 10 which also supports the riser sections 2. In figure 2, the cart 7 is not present in the riser section handling station 5. Gaps between adjacent track sections 6 are bridged by track section links 9 which are not drawn in detail. The track section links 9 provide a substantially continuous track, and thus allow the overhead crane 4 to move along the track in a substantially bump free manner.

The overhead crane 4 comprises grippers 11 , a crane cart for moving the crane along the track. The grippers 11 may be lowered towards the riser sections 2. In such an embodiment, the top entry opening of the transport containers is larger than the length of the riser sections, such that the grippers can be lowered into the transport containers and alongside the outer ends of the riser sections, to engage a riser section at those outer ends.

In fig. 3, the grippers 11 of the overhead crane 4 are in a transport position allowing the overhead crane 4 to move between riser section transport containers 3. Fig. 3 shows a front view of the modular riser section storage and handling system of figure 1. The box like stacking frame 10 can be viewed in more detail in figure 3. The stacking frame 10 in the figure comprises several vertical beams and horizontal beams that support the riser sections 2. The overhead crane 4 is placed on top of the track sections 2.

Fig. 4 shows a front view of an empty modular riser section storage and handling system 1 placed on the deck 12 of a vessel. The riser section transport container 3 shown in figure 4 does not contain riser sections 2. The grippers 11 of the overhead crane 4 are in a lowered position.

The modular riser section storage and handling system shown in the figures allows for a method according to the claimed invention. Such a method comprises the steps of:

- Storing the riser sections 2 for use in wellbore drilling activities in the riser section transport containers 3, wherein each one of the multiple riser section transport containers 3 comprises an overhead track section 6 which overhead track section 6 is located on the top side of the respective riser section transport container 3.

- Placing the riser section handling station 5, adapted for handling riser section, on the deck 12 of the vessel, wherein the riser section handling station 5 comprises an overhead track section 6 which overhead track section 6 is located on a top side of the riser section handling station 5.

- Placing the multiple riser section storage transport containers 3 adjacent to each other and to the riser section handling station 5 in the storage configuration on the deck 12 of the vessel, wherein the track sections (6) of the riser section transport containers (3) and the track section (6) of the riser section handling station (5) form an overhead track.

- Placing the overhead crane 4 adapted for lifting riser sections 2 on the overhead track.

- Moving the vessel to a wellbore drilling location.

- Using the overhead crane 4 to lift riser sections 2 from the riser section transport containers 3 and transporting the riser sections 2 to the riser section handling station 5 for use in wellbore drilling activities.

In a further embodiment, the multiple riser section transport containers 3 and the riser section handling station 5 comprise connector devices for connecting adjacent riser section transport containers 3 and the riser section handling station 5 when the multiple riser section transport containers 3 and the riser section handling station 5 are set up in the storage configuration on the deck 12 of the vessel, and the method further comprises the step of connecting the adjacent riser section transport containers 3 which are placed on the deck 12 of the vessel and the riser section handling station 5 to each other with connector devices.

In a further embodiment, the riser section transport containers 3 are provided with securing devices for securing the transport containers 3, in the storage configuration, to mounts on the deck 12 of the vessel, and the method further comprises the step of securing the multiple riser section transport containers 3 and the riser section handling station 5 to the deck 12 of the vessel using the securing devices.

Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from study of the drawings, the disclosure, and the appended claims. In the claims, the word“comprising” does not excluded other elements or steps, and the indefinite article“a” or“an” does not exclude a plurality. A single processor or other unit may fulfil the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

The invention is by no devices limited to the exemplary embodiment described herein above, but comprises various modifications hereto, in so far as they fall within the scope of the following claims.

Reference signs

01 modular riser storage and handling system 02 riser sections

03 riser section transport containers

04 overhead crane

05 riser section handling station

06 track section

07 cart

08 cart track

09 track section links

10 stacking frames

11 grippers

12 deck vessel

13 top entry opening

14 overhead crane control device

15 overhead track

16 track component

17 bottom side transport container

18 first side transport container

19 second side transport container

20 first end transport container

21 second end transport container