WO2018097718A1

WO2018097718A1 - Method of installing a protective coating

Info

Publication number: WO2018097718A1
Application number: PCT/NL2017/050767
Authority: WO
Inventors: Ivano CARUSO
Original assignee: Heerema Marine Contractors Nederland Se
Priority date: 2016-11-24
Filing date: 2017-11-23
Publication date: 2018-05-31
Also published as: NL2017868B1

Abstract

The present invention relate to a support device configured for holding a pre-heated coating sheet and moving the pre-heated coating sheet from a remote position to a coating position on a pipeline or pipe section, the device comprising: - a support frame comprising at least a first curved frame part and a second curved frame part which are movable relative to one another between an open state and a closed state, wherein in the open state the first and second curved frame part define an opening for a pipeline or pipe section, wherein in the closed state the first and second curved frame part surround a cylindrical volume which is configured for accommodating the pipeline or pipe section, - at least one sheet holder arranged on an inner side of the support frame and supported by the support frame, the at least one sheet holder being configured to engage the pre-heated coating sheet and support the pre-heated coating sheet on an inner side of the support frame during the movement of the support frame, - a transport drive configured for moving the support frame in the open state from the remote position to the coating position, - a frame part actuator for moving the first curved frame part and second curved frame part relative to one another from the open state to the closed state for bending the pre-heated coating sheet which is held by the at least one sheet holder around the circumference of the pipeline or pipe section.

Description

Title: Method of installing a protective coating FIELD OF THE INVENTION

The present invention relates in general to improvements in the field of pipe coating.

In a first aspect, the present invention relates to a method and support device configured for holding a pre-heated coating sheet and moving the pre-heated coating sheet from a remote position to a coating position on a pipeline or pipe section.

In another aspect, the present invention relates to a method and system for heating a coating sheet constructed to form a coating on a pipeline or pipe section. In yet another aspect, the present invention relates to a method and support device for applying pressure on a pre-heated coating sheet which is folded around a pipeline or pipe section.

The present invention further relates to a coating sheet for making a pipe coating.

BACKGROUND OF THE INVENTION

The laying of pipelines on a seabed has seen a tremendous growth over the last decades. The driving factor for this development was and is the exploration and production of hydrocarbons in ever deeper waters. As a consequence, the technology of laying pipelines from a pipeline laying vessel has also seen tremendous developments. Nowadays, the depths at which pipelines are currently laid exceed well over 3000 meter. Furthermore, the speed at which pipelines are laid is also continuously increasing.

Generally, subsea pipelines are provided with a coating. The coating has several advantages. One advantage is that the coating provides a thermal insulation. Hydrocarbons which flow from a borehole may be warm or hot and should not cool excessively during transport through the pipeline, because wax in the hydrocarbons may solidify and be deposited on the inner wall of the pipeline. This may result in clogging of the pipeline. The coating keeps the hydrocarbons warm during transport.

Another advantage of the coating is mechanical protection of the pipeline. The coating prevents the pipeline from being damaged. Another advantage is corrosion prevention. The coating prevents the sea water from contacting the pipe wall, which is generally made of steel.

The coating of the pipelines is therefore an important aspect of marine pipelay.

Coating generally involves a coating process of the individual pipe sections which make up a pipeline. A large portion of the individual pipe sections are coated. Only the ends are left bare in order to allow end-to-end welding of the pipe sections into a pipeline. After the weld is made, the weld region (also called the joint) is coated in a separate process. The coating of joints may be carried out on shore, when several pipe sections are welded into a quad joint or hex joint, comprising respectively four or six pipe sections.

The coating of the joints may also take place on a pipeline laying vessel during the pipelay process itself. This kind of coating of joints is generally referred to as a field joint coating (FJC), because it is a joint coating which is made in the field.

In general, quality and speed are crucial in the pipeline laying industry. This also applies to the coating process. Both the coating of the lengths of the individual pipe sections and the coating of the joints on shore and in the field needs to be performed with a high quality and at a high speed.

The speed aspect applies in particular to FJC's. Vessels that lay pipeline may cost in excess of 1 billion Euro and as a consequence they have very high daily operating costs. A typical pipeline laying project may take several weeks and every hour that can be saved in such a project drives down the costs.

In the present invention it was recognized that the available methods of coating have certain drawbacks. One important limiting factor in the speed of pipeline laying operations is that after a new pipe section has been welded to the free end of the pipeline, the joint (generally called field joint) must be coated with a Field Joint Coating. The process of applying a Field Joint Coating lies on the critical path.

The ends of each pipe section (which pipe section may be a hex joint or quad joint) are bare, in order to allow the welding of the pipe section to the free end of the pipeline. After the welding is completed, the Field Joint Coating is applied. Currently, there are several methods for making an FJC. Each method has its own advantages and limitations.

1. Injection moulding. This method involves a mould which is positioned around the Field Joint (FJ) area. The mould is then filled with a molten, liquid plastic such as polypropylene. Next, the plastic cools off until it has completely solidified. Subsequently the mould is removed. The method generally also involves the application of an anti-corrosion coating such as fusion bonded epoxy (FBE) prior to applying the plastic. Often, an adhesive is also applied on the anti-corrosion coating.

The injection moulding method works, but it has a drawback that a lot of heat needs to be applied to melt the plastic. Subsequently the same heat needs to be removed from the material in a cool-down period in order to solidify the coating. The subsequent cool-down period is quite long because the plastic itself is thermally insulating. Therefore, the heat dissipates very slowly, and this slows down the entire pipe laying process. A FJC with injection moulding may take 10-20 minutes to manufacture. If the pipeline laying process is carried out with hex-joints (6 interconnected pipes section of 12 meter plus a forging of 3 meter is 75 meter) then every 75 meter a 10-20 minute delay is incurred. If six pipe sections are laid on an average day then the making of the FJC's may cost in the order of one to two hours per 24 hours.

The method has an additional drawback in that it is a complex process. Many parameters need to be controlled. It is also a sensitive process, because a change in the viscosity of the molten material or the amount of heat applies may lead to a lower quality of the coating. The method further requires expensive and bulky equipment.

WO2008/042342A2 discloses an example of such a process. See in particular paragraphs 41 and 42 of WO2008/042342A2. A mould formed by a sheath material is positioned around the field joint. The mould forms a cavity which is subsequently filled with infill material. This has the disadvantage of a long cool-down period which is mentioned above.

2. Heat shrink sleeves. (HSS) A sleeve of a heat shrink material is positioned around the Field Joint area. Subsequently, heat is applied and the sleeve shrinks. The heat is often applied with manually operated torches. Automated heat application means are also possible. The application of heat is difficult. It is in particular difficult to apply the heat in a uniform manner. This leads to a disadvantage in that the quality of these FJC's is not consistent. For this reason HSS is discontinued by many pipeline owners or operators.

3. Spiral tape wrapping. The entire FJ area is wrapped with tape. This method works for horizontal pipe (S-lay) but has not yet been proven to work satisfactorily for vertical pipe (J-lay). This method is extremely time consuming as it involves heating, double winding and compressing a strip of coating which is much narrower than the FJ (typically 1/10^th to 1/20^th of the FJ axial length). 4. "Cigarette" wide tape wrapping. This is a variant of tape wrapping wherein a tape is used which has a same width as the length of the Field Joint area. In this way, spiral wrapping is not necessary to ensure coverage of the entire substrate. However, multiple turns need to be performed to achieve the specified thickness. Generally , the tape is supplied as roll consumable or extruded on the spot with an extrusion machine and a roller is used to apply pressure on the tape during the wrapping process.

WO2015/079249A1 discloses a system of the prior art which is a variant to injection moulding. Instead of pumping a liquid thermoplastic material into a mould and letting the material harden, two bodies of thermoplastic material are positioned within a mould around the Field joint area. Next, the bodies are heated and molten in the mould. The bodies then are attached to the pipeline and to each other. Subsequently , the bodies are cooled again in order to harden. Next, the mould is removed and the FJC is ready.

The system of WO2015/079249A1 has a disadvantage in that the heating and cooling off of the thermoplastic material is carried out in the critical path. This takes a lot of time and consequently this system is very slow. Moreover, the handling of the bodies and the mould is quite difficult, which makes this system very cumbersome. Adhesion to the substrate is also questionable due to the coexistence of materials with different often opposite behaviours (e.g. thermoplastic and thermosetting)

WO2008107759A1 discloses another system in which a thermoplastic sheet is laid on a supporting sheet. Subsequently, the combination of the thermoplastic sheet and the supporting sheet is wound around the pipeline. This system has various disadvantages. First, the application of heat to the thermoplastic sheet is quite difficult. The thermoplastic sheet is in a horizontal orientation and there is no practical method disclosed or available to apply the heat in such a situation. Furthermore, the handling of the thermoplastic sheet is difficult. Because the coating sheet is oriented horizontally, it will tend to sag bend when picked up at the edges or picked up at one edge. This method is in particular not suitable for J-lay, because in J-lay the pipeline is essentially vertical.

Further, the system relies on the principle of rollers pressing the coating sheet to the substrate in order to create the necessary adhesion. This means that any minor

misalignment, any malfunction of the rollers or any of the moving parts (e.g. bearings, supporting brackets, motors, systems to control the pressure, the speed and the extent of the rotation) may cause the pressure to be locally inadequate. This may compromise the adhesion of the coating sheet to the substrate or the integrity of the coating sheet itself (e.g. deformation, indentations in areas where the pressure is excessive)

Another disadvantage is that the supporting sheet and the pressing

mechanism/components (rollers, etc.) must be dimensioned specifically to the geometry of the substrate; variations of the FJ size (typical tolerance on the axial length is -0/+60mm to the nominal value) require adjustment to such components of the machine. This makes the method of WO2008107759A1 very cumbersome. Also, the supporting sheet must be flexible enough to be wound around the substrate, yet stiff enough to transmit the pressure to the coating sheet. In practice it is quite difficult to achieve a proper rigidity/flexibility of the supporting sheet.

The coating of separate pipe sections on shore is generally carried out with an extrusion process.

OBJECT OF THE INVENTION

It is an objective of the invention to provide a system and method with which a high quality coating of a pipe section or a joint can be made.

It is another objective of the invention to provide a system and method with which a more robust FJC can be made than with the prior art. Robust in this context means:

performing as required under a wider range of conditions, in particular performing as required under the heavy loads which are exerted on the FJC after the manufacture. It is another objective of the invention to provide a system and method with which an FJC can be made with simpler equipment.

It is another objective of the invention to provide a system and method with which an FJC can be made with less energy than according to the prior art.

It is another objective of the invention to provide a system and method with which an FJC can be made faster than with the prior art.

SUMMARY OF THE INVENTION

First aspect of the invention: support device and method configured for holding a preheated coating sheet

In a first aspect, the invention provides a support device configured for holding a preheated coating sheet and moving the pre-heated coating sheet from a remote position at a distance from a pipeline or pipe section to a coating position on a pipeline or pipe section, the device comprising:

- a support frame comprising at least a first curved frame part and a second curved frame part which are movable relative to one another between an open state and a closed state, wherein in the open state the first and second curved frame part define an opening for a pipeline or pipe section, wherein in the closed state the first and second curved frame part surround a cylindrical volume which is configured for accommodating the pipeline or pipe section,

- at least one sheet holder arranged on an inner side of the support frame and supported by the support frame, the at least one sheet holder being configured to engage the pre-heated coating sheet and support the preheated coating sheet on an inner side of the support frame during the movement of the support frame,

- a transport drive configured for moving the support frame in the open state from the remote position to the coating position,

- a frame part actuator for moving the first curved frame part and second

curved frame part relative to one another from the open state to the closed state for bending the pre-heated coating sheet which is held by the at least one sheet holder around the circumference of the pipeline or pipe section, - a pressing system (33) arranged on an inner side of the curved frame parts, the pressing system being configured to press the pre-heated coating sheet against the pipeline or pipe section, wherein the pressing system is configured to apply the coating sheet on a Field Joint area (15) where two pipe sections (41 ,42) are joined together in an end-to end relationship, wherein the applied coating sheet extends on both sides of the joint.

The invention advantageously provides an alternative way of applying a coating sheet on a pipeline or pipe section.

The remote position may be a treatment position, in particular a heating position. The remote position may also be a storage position.

In comparison with the present prior art, several advantages may be provided:

- a reduction of the cycle time is possible because any and/or all of the following is possible: pre-heating of the coating sheet is performed in non- critical time, pre-heating of the coating sheet is performed on specifically selected areas to reduce the cool down stage required for the solidification of the coating sheet or to avoid it altogether, applied coating is capable of withstanding mechanical loads earlier after the application is complete compared to the existing art, no revolutions or windings around the substrate are necessary to achieve the specified thickness;

- the quality of applied coating is improved by eliminating the risk of air entrapment, voids, inter-layer delamination which ultimately compromise the adhesion to the substrate;

- the reliability of the equipment is increased thanks to the drastically reduced number of components used and parameters to be monitored and / or kept under control;

- shape variations of the substrate to be coated can be coped with within

range;

In an embodiment, the sheet holder comprises a first sheet holder part having a shape of a part of a cylinder an connected to the first curved frame part and a second sheet holder part having a shape of a part of a cylinder and connected to the second curved frame part. This provides the benefit that the coating sheet can be held in a shape in which it can be easily applied to a pipeline or pipe section. In an embodiment, the pressing system comprises one or more inflatable bodies which are constructed to be inflated from an empty state to a filled state for pressing the preheated coating sheet against the pipeline or pipe section once the device is in the closed state and surrounds the pipeline or pipe section. It was found that this way or pressing allows a very uniform pressure to be created, resulting in a very effective bonding of the coating sheet onto the pipeline or pipe section.

In an embodiment, at least one inflatable body is positioned on a pipeline side of the support frame and wherein the at least one sheet holder is arranged on an inner side of the inflatable body. The sheet holder effectively holds the coating sheet in the desired position.

In an embodiment, the inflatable body has an at least partially curved shape, in particular the shape of a part of a cylinder. This shape advantageously allows a very effective bonding of the coating sheet to the pipeline or pipe section.

In an embodiment, the first curved frame part and the second curved frame part are interconnected by a hinging connection. The hinging connection allows an accurate pivoting movement of the curved frame parts relative to one another. In an embodiment, the support frame comprises a third frame part, wherein the third curved frame part is pivotable relative to the second curved frame part via a second hinging connection. In this way, the support frame has a central part and two "doors" which effectively allow the support device to be positioned around a pipeline or pipe section. In an embodiment, the at least one sheet holder comprises a manifold body comprising an internal air duct, an outlet opening and suction members . Suction was found to allow a very well controllable supporting of the coating sheet. The sheet holder may also comprise physical supports such as a toe rest to support the heated sheet in the support device. The toe rest may be combined with the inflatable body.

In an embodiment, the support device comprises a first sheet holder which is connected to the first curved frame part and a second sheet holder which is connected to the second curved frame part or in case of a support frame having three curved frame parts, a first sheet holder which is connected to the first curved frame part, a second sheet holder which is connected to the second curved frame part and a third sheet holder which is connected to the third curved frame part. This configuration allows both a very accurate positioning and an accurate and well controlled support of the coating sheet. In an embodiment, the at least one sheet holder is indirectly connected to the support frame via the pressing system. In this way the pressure of the pressing system is exerted onto the coating sheet via the sheet holder. In an embodiment, the support device comprises a base which is movable on tracks by the drive, an actuator for moving a support section comprising the first part, second part and third part up and down, and an actuator for moving the support section in a lateral direction. This embodiment allows a three dimensional movement procedure from the heating device to the pipeline or pipe section which is to be coated.

In the first aspect, the present invention further relates to a method for holding a preheated coating sheet and moving the pre-heated coating sheet from a remote position at a distance from a pipeline or pipe section to a coating position on a pipeline or pipe section, the method comprising:

- engaging the pre-heated coating sheet in the remote position by at least one sheet holder of the support device according to any of the preceding claims, wherein a first sheet part is held in a first curved shape by a first curved frame part and a second sheet part is held in a second curved shape by a second curved frame part, wherein the first and second curved frame part hold the pre-heated coating sheet in an open state which defines an access for the pipeline or pipe section,

- moving the support frame in the open state by the transport drive from the remote position to the coating position at the pipeline or pipe section,

- moving the first curved frame part and the second curved frame part relative to one another from the open state to the closed state by the frame part actuator, wherein the pre-heated coating sheet is bent around the circumference of the pipeline or pipe section and engages the circumference of the pipeline or pipe section and forms a cylindrical pipe coating

- wherein the coating sheet is applied on a Field Joint area where two pipe sections are joined together in an end-to end relationship.

The method provides the same advantages as the device.

In an embodiment, the pre-heated coating sheet is supported in an open state prior to moving the coating sheet to the coating position, wherein the coating sheet comprises a first sheet part which has the shape of a part of a cylinder and a second sheet part which has the shape of a part of a cylinder, said first and second sheet part being connected by an intermediate sheet part, wherein the coating sheet comprises a first end portion and a second end portion which in the open state are at a distance from one another, the method comprising folding the pre-heated coating sheet around the pipe section or pipeline and letting the first end portion and second end portion engage one another. It was found that this way of positioning the coating sheet involves relatively few movements and

deformations of the coating sheet, and results in an accurate and well controlled positioning.

In an embodiment, the intermediate sheet part forms a living hinge and is bent during the bending of the sheet around the pipeline or pipe section. In this way good use is made of the flexibility of the coating sheet during the positioning step.

In an embodiment, the method comprises pressing the pre-heated coating sheet with a pressing system against the pipeline or pipe section during a pressing time period, during which pressing time period an adhesion of the coating sheet to the substrate is achieved and the coating sheet cools off. The pressing results in a high quality bond between the coating sheet and the pipeline.

In an embodiment, the pressing system comprises one or more inflatable bodies, wherein the one or more inflatable bodies are inflated from an empty state to a filled state and press the coating sheet against the pipeline or pipe section. The pressure of the one or more inflatable bodies can be accurately controlled and uniformly applied.

In an embodiment, the method comprising pressing the pre-heated coating sheet against the pipeline or pipe section according to a pre-established pressure-time curve during which the pressure is varied. This makes it possible to apply the pressure in a specific way and for instance in dependence of the temperature or other parameters.

In an embodiment, the pressure is applied on the pre-heated coating sheet in different pressure zones by associated different inflatable bodies, and wherein the pressure in a first pressure zone is different from the pressure in a second pressure zone. In this embodiment a high pressure can be applied where it is needed, and a relatively low pressure can be applied where possible.

In an embodiment, a layer of fusion bonded epoxy (FBE) is applied to the pipeline or pipe section and wherein a layer of adhesive is applied onto the FBE prior to the moving of the pre-heated coating sheet to the coating position. This increases the corrosion resistance of the resulting pipe coating. In an embodiment, the first and second curved frame part are locked around the pipeline or pipe section with a locking device prior to the pressurization step. This allows a high pressure to be generated on the coating sheet with relatively little deformation of the curved frame.

In an embodiment, the coating sheet has an inner, pipeline side and an outer side, and wherein the coating sheet is pre-heated before being moved to the coating position, wherein the coating sheet is pre-heated only on the pipeline side of the coating sheet, wherein the pipeline side is brought into a softened ormolten state, wherein the pipeline side is subsequently pressed against the pipeline in the pressing step. This effectively reduces the amount of energy needed for the coating operation and reduces the time needed for the cooling off of the coating. This is a very focussed way of applying heat. The heat required to promote adhesion is now applied onto 'half molten material'. In an embodiment, the pre-heated coating sheet is moved from the remote position to the coating position in a vertical orientation. This was found to be very effective for J-lay. In another embodiment, the pre-heated coating sheet is moved to the coating position in a vertical orientation. This embodiment is in particular suitable for S-lay or for coating a pipeline or pipe section on shore, for instance in a spool base. For reel lay, the pipeline or pipe section may be horizontal, vertical or even inclined.

In an embodiment, the at least one sheet holder comprises suction members and the coating sheet is supported by applying suction on the coating sheet by the suction members. Suction allows an accurate and well controlled support of the coating sheet

After the bending step a single pre-heated coating sheet fully surrounds a

circumference of the pipeline or pipe section.

The present invention is in particular suitable to make a Field Joint Coating.

In an embodiment, the coating sheet is applied on a Field Joint area where two pipe sections are joined together in an end-to end relationship, wherein the joint is formed by a J lay installation on board a pipeline laying vessel. In J-lay, the pipeline extends substantially vertically and the present invention was found to very effective for manufacturing pipe coating in a substantially vertical orientation.

In an embodiment, during the bending step the curvature of the coating sheet is changed, in particular by pivoting the first curved frame part relative to the second curved frame part, wherein the coating sheet is wrapped around the pipeline, wherein a first and second end region of the coating sheet meet one another and form a seam. In this way, the coating sheet completely encircles the pipeline or pipe section with a predetermined and relatively little deformation.

In an embodiment, the first and second end region overlap. The overlapping ensures a complete sealing of the pipeline or pipe section.

In an embodiment, the first and second end region are connected to one another by pressing them onto one another with the pressing device and letting the previously applied heat form the connection between the first and second end region. This is a very simple and effective way of making the connection.

In an embodiment, at least one edge in the end region of the coating sheet is chamfered. The chamfered edge prevents sudden transitions in the outer side of the resulting pipe coating.

In an embodiment, the coating sheet comprises a first main area and a second main area and a weld bead area, wherein in the weld bead area the coating sheet has a thickness which is greater than the thickness of the first and second main areas, wherein in the positioning step the weld bead area is positioned on a weld bead on the pipeline or pipe section, wherein the weld bead area is in particular a band extending across the coating sheet dividing the first main area from the second main area. The weld bead area provides a thicker pipe coating where it is needed, i.e. in the region of the weld bead.

In an embodiment, the method is carried out on a pipeline installation vessel during a pipeline laying operation, wherein the method of pipelay is in particular J-lay and wherein the coating sheet is held substantially vertically throughout the process.

In an embodiment, the method is carried out on a pipe section on shore. The present invention is also suitable to be carried out on shore, either on joints between pipe section or as a coating extending along the length of an individual pipe section, wherein the ends of the pipe section are generally not coated to allow welding of the ends.

In an embodiment, during the step of moving the pre-heated coating sheet from the remote position to the coating position the coating sheet has a curved shape and is in an open state. This reduces the required deformations of the coating sheet during the entire procedure and improves the quality of the resulting pipe coating.

In an embodiment, the remote position is a heating position where the coating sheet is pre-heated. This is the basic configuration of the invention.

In an embodiment, during the moving step the coating sheet is lifted upward from the heating device. This movement reduces a risk of collision between the coating sheet and the heating device . It also allows the heating device to have a larger diameter than a gap between the ends of the coating sheet in the heating position. This in turn allows the heating elements to be positioned very close to the coating sheet.

Second aspect of the invention, system and method for heating a coating sheet

In a second aspect, which can be viewed independently from the first aspect, the invention provides a system for heating a coating sheet constructed to form a coating on a pipeline or pipe section, the system comprising:

- a support device configured to support the coating sheet in a heating position, the support device comprising a support frame and at least one sheet holder supported by the support frame, wherein the sheet holders are configured to collectively support the coating sheet,

- a heating device comprising a plurality of heating elements arranged to heat only a part of the coating sheet .

Because the heating device only heats a part of the coating sheet, energy can be saved. Also a subsequent cooling off period can be shorter, because less energy needs to be dissipated. This increases the speed of coating a pipeline or pipe section and ultimately increases the pipelay process.

Furthermore, a part of the coating sheet which is not heated stays hard and can be used to engage the coating sheet with a sheet holder. This advantageously allows supporting the coating sheet in the desired position during the heating and allow

subsequently moving the coating sheet to the pipeline or pipe section and positioning the coating sheet around the pipeline or pipe section.

In an embodiment, wherein the heating elements are arranged to heat only one side of the coating sheet in the heating position. Because the other side of the coating sheet is not heated, this side stays hard and can be engaged to hold, move and position the coating sheet. In an embodiment, the support device is configured to support the coating sheet in an at least partially curved form during the heating, defining an inner side and an outer side of the support sheet, and wherein the heating device is configured to heat the inner side. Because the outer side stays hard, it can be engaged hold, move and position the coating sheet. Moreover, an inflatable body can be used to press against the outer side to press the coating sheet against the pipeline or pipe section which is to be coated.

In an embodiment, the heating elements are mounted on a central frame, wherein the support device supports the coating sheet in a form in which it at least partially surrounds the heating elements, wherein the heating elements are arranged to radiate heat outwardly and radially away from the central frame and toward the coating sheet. This allows the coating sheet to have shape which is quite similar to the shape of the pipeline or pipe section to be coated and reduces required deformations of the coating sheet during the coating process.

In an embodiment, the support device is configured for moving the heated sheet from the heating position to a pipeline or pipe section and for pressing the heated sheet against the pipeline to form the coating. This obviates a need for any handover of the coating sheet from a separate support device used during the heating to a separate support device used for moving the coating sheet.

In an embodiment, the support device comprises a support frame and an inflatable body positioned on a pipeline side of the support frame for pressing the heated sheet against a pipeline or pipe section. Advantageously, the support device can also press the coating sheet onto the pipeline or pipe section with a very uniform and/or well controlled pressure.

In an embodiment, the support frame comprises a first curved frame part and a second curved frame part adapted to extend around at least a part of the pipeline or pipe section, wherein the first curved frame part and the second curved frame part are movable relative to one another between a closed position and an open position, wherein the support device comprises a frame part drive for closing the first and second curved frame part around the pipeline or pipe section. This arrangement provides a benefit in that the support device can fully surround a pipeline or pipe section which is to be coated.

In an embodiment, the support device is configured to move the heated sheet from the heating position to the coating position in an at least partially curved form. In an embodiment, a trajectory from the heating position to the coating position comprises a first trajectory part which is directed upward, wherein the support device is configured to move the heated sheet away from the heating position in the upward direction along said first trajectory part.

In an embodiment, the support device comprises at least a first curved frame part and a second curved frame part interconnected by a hinging connection.

In an embodiment, the support device comprises the first curved frame part, the second curved frame part and a third curved frame part, wherein the third curved frame part is pivotable relative to the second curved frame part via a second hinging connection.

In an embodiment, the heating device extends upward from a floor, wherein the heating device comprises a plurality of heating elements, which in top view are arranged in a curved shape, in particular in a C-shape.

The heating elements may be radiant heating elements. The radiant heating elements may be infra red lamps.

In the second aspect, the invention further relates to a method of heating a coating sheet constructed to form a coating on a pipeline or pipe section with the system for heating a coating sheet, the method comprising:

- supporting the coating sheet with a support device at a heating device,

- heating only a part of the coating sheet with the heating device.

In an embodiment, wherein the coating sheet has an inner side intended to be positioned against the pipeline or pipe section and wherein only the inner side is heated, wherein the inner side is brought into a softened or molten state and wherein an outer side remains in a solid state.

In an embodiment, the coating sheet is supported in an at least partially curved form during the heating.

In an embodiment, the heating elements are mounted on a central frame and wherein the support device supports the coating sheet in a form in which it at least partially surrounds the heating elements, wherein the heating elements radiate heat outwardly and radially away from the central frame and toward the coating sheet. In an embodiment, the method comprises:

a. heating a part of the coating sheet in the heating position during a first time period (T1) with the heating device,

b. moving the coating sheet comprising the heated part from the heating position to the pipeline or pipe section and positioning the coating sheet around the pipeline or pipe section to be coated, wherein the heated sheet engages the pipeline or pipe section and surrounds the circumference of the pipeline, c. pressing the coating sheet against the pipeline during a second time period (T2), during which second time period an adhesion of the coating sheet to the substrate is achieved and the coating sheet cools off.

In an embodiment, the coating sheet is pressed against the pipeline or pipe section according to a pre-established pressure-time curve, wherein the applied pressure is measured during the pressing and wherein the pressure is maintained until pre-determined pressure values are achieved over the entire sheet or over a part of the coating sheet.

In an embodiment, the pressure is applied on the coating sheet in different pressure zones by associated different inflatable bodies, and wherein the pressure in a first pressure zone is different from the pressure in a second pressure zone.

In an embodiment, the coating sheet is heated and moved from the heating position to the pipeline or pipe section to be coated in a vertical orientation.

In an embodiment, the heating position is located at a distance from the pipeline and the support device is movable and is configured to move the coating sheet from the heating position to the coating position, wherein the support device picks up the coating sheet at the heating position and holds the coating sheet during the movement from the heating position to the coating position.

In an embodiment, the support device comprises at least one sheet holder which comprises suction members and wherein the coating sheet is supported by applying suction on the coating sheet by the suction members.

In an embodiment, a single sheet fully surrounds the circumference of the pipeline.

In an embodiment, during the positioning step the curvature of the coating sheet is changed by the support device, in particular by pivoting a first curved frame part and a second curved frame part relative to one another, wherein the coating sheet is wrapped around the pipeline, wherein a first and second end region of the coating sheet meet one another and form a seam.

In an embodiment, the first and second end region overlap.

In an embodiment, the first and second end region are connected to one another by pressing with the support device and letting the previously applied heat form the connection between the first and second end region. In an embodiment, the coating sheet comprises a first main area and a second main area and a weld bead area, wherein in the weld bead area the coating sheet has a thickness which is greater than the thickness of the first and second main areas, wherein in the positioning step the weld bead area is positioned on a weld bead of a joint between two pipe sections, wherein the weld bead area is in particular a band extending across the coating sheet dividing the first main area from the second main area.

In an embodiment, the support device comprises at least a first curved frame part and a second curved frame part which are interconnected by a hinging connection, and wherein the first curved frame part and the second curved frame part are movable relative to one another from an open state to a closed state, wherein during the positioning step the first and second curved frame part are moved into the closed state and wherein during the pressing step the support device remains closed.

In an embodiment, during the heating step the coating sheet has a C-shape and extends at least partially around the heating device.

In an embodiment, during the moving step the coating sheet is lifted upward from the heating device.

Third aspect of the invention: support device and method for applying pressure on a pre-heated coating sheet In a third aspect, the present invention relates to a support device for applying pressure on a pre-heated coating sheet which is folded around a pipeline or pipe section, the support device comprising:

- a support frame comprising at least a first curved frame part and a second curved frame part which are movable relative to one another between an open state and a closed state, wherein in the open state the first and second curved frame part define an opening for the pipeline or pipe section, wherein in the closed state the first and second curved frame part surround a cylindrical volume which defines a pipe position and which is configured for accommodating a pipeline or pipe section,

a pressing system arranged on an inner side of the first and second curved frame parts, the pressing system comprising at least one inflatable body, wherein the at least one inflatable body is constructed to be inflated from an empty state to a filled state for pressing the pre-heated coating sheet which is positioned on the inside of the at least one inflatable body against the pipeline or pipe section.

The support device is capable of applying a controlled pressure onto the coating sheet, resulting in a high quality pipe coating. In an embodiment the support device is capable of applying a uniform pressure onto the coating sheet further improving the quality of the pipe coating.

In an embodiment, in the closed state the at least one inflatable body has an at least partially curved shape, in particular a shape of a part of a cylinder.

In an embodiment, the device comprises multiple inflatable bodies positioned on the inside of the support frame and comprising a filling system configured to inflate the inflatable bodies at different pressures. The term multiple inflatable bodies is intended to also cover an embodiment in which a single inflatable body is compartmentalized. This allows that pressure can be applied/controlled individually per compartment for better pressure control and also prevents air from being trapped.

In an embodiment, the first curved frame part and the second curved frame part are interconnected by at least one hinging connection, and are movable relative to one another between an open position and a closed position, wherein the at least one inflatable body moves with the first and second curved frame part, wherein the support device comprises a frame actuator for closing the support device around the pipeline. In an embodiment, the support device comprises the first curved frame part, the second curved frame part and a third curved frame part interconnected by two hinging connections. In an embodiment, the device is movable between a heating position at a heating device and a coating position at the pipeline or pipe section.

In an embodiment, the device comprises at least one sheet holder arranged on the inside of the first and second curved frame parts and configured to hold the coating sheet in position during the pressurization step.

In an embodiment, the at least one sheet holder is arranged on the inside of the at least one inflatable body, wherein the at least one sheet holder comprises in particular suction holes for applying suction on an outer side of the coating sheet.

In an embodiment, the support device comprising an entry in the inflatable body for entry of air or other fluid, wherein said entry is located in a central region of the inflatable body which is at a farthest distance from ends of the inflatable body. The present invention further relates to a system comprising:

- the support device according to the present invention,

- a heating clamp unit configured to be positioned around a coated pipeline or pipe section, wherein the heating clamp unit comprises clamp heating elements arranged on an inner side of the heating clamp unit, wherein the clamp heating elements are configured to heat an outer surface of a coating on the pipeline or pipe section.

The heating clamp unit provides an advantage in that multiple layers of coating sheet can be applied onto the pipeline or pipe section on top of one another. A good bonding between the coating layers is possible with the heating clamp unit.

Invention 3 method claims

In the third aspect, the present invention further relates to a method of forming a coating on a pipeline or pipe section by pressing a pre-heated coating sheet against the pipeline or pipe section with the support device of the present invention, the method comprising: a. positioning the pre-heated coating sheet around the pipeline or pipe section and within the support device according to the present invention, wherein the pre-heated coating sheet is positioned on an inner side of the at least one inflatable body,

b. inflating the at least one inflatable body by filling it with a pressurized fluid and pressing the pre-heated coating sheet against the pipeline during a cooling period, during which cooling time period the coating sheet cools off and an adhesion of the coating sheet to the pipeline or pipe section is established.

The method provides the same advantages as the support device according to the present invention.

In an embodiment, the pressing is performed according to a pre-established pressure-time curve during which the pressure is varied in time, wherein the pressure is measured.

In an embodiment, the pressure is applied on the pre-heated coating sheet with a plurality of inflatable bodies.

In an embodiment, the pressure is applied on the pre-heated coating sheet in different pressure zones by associated different inflatable bodies, and wherein the pressure in a first pressure zone is different from the pressure in a second pressure zone.

In an embodiment, a layer of fusion bonded epoxy (FBE) is applied to the pipeline or pipe section and a layer of adhesive is applied onto the layer of FBE prior to the positioning the pre-heated coating around the pipeline or pipe section.

In an embodiment, the pipeline or pipe section is oriented vertically.

In an embodiment, the coating is formed on board a pipeline laying vessel during a pipelay operation, wherein the vessel comprises a J-lay system or an S-lay system.

In an embodiment, the coating is formed on shore on a pipe section and wherein the coating covers at least 80 percent of a length of said pipe section.

In an embodiment, the pre-heated coating sheet has an inner, pipeline side and an outer side, and wherein the pipeline side is in a softened or molten state during the pressing and wherein the outer side is in a solid state during the pressing. In an embodiment, the pre-heated coating sheet is wrapped around the pipeline, wherein a first and second end region of the coating sheet meet one another and form a seam. In an embodiment, the first and second end region overlap.

In an embodiment, the first and second end region are connected to one another by pressing with the support device and letting the previously applied heat form the connection between the first and second end region. In an embodiment, the coating sheet comprises a first main area and a second main area and a weld bead area, wherein in the weld bead area the coating sheet has a thickness which is greater than the thickness of the first and second main areas, wherein in the positioning step the weld bead area is positioned on the weld bead of a joint connecting two pipe sections, wherein the weld bead area is in particular a band extending across the coating sheet dividing the first main area from the second main area.

In an embodiment, the first curved frame part and the second curved frame part are movable relative to one another from an open position to a closed position, wherein during the positioning of the pre-heated coating sheet around the pipeline the first and second part are moved into the closed position.

In an embodiment, the pipeline or pipe section is already coated with a coating layer , and wherein prior to positioning the pre-heated coating sheet around the pipeline or pipe section with the support device, a heating clamp unit is positioned around the coated pipeline or pipe section, wherein the heating clamp unit comprises clamp heating elements arranged on an inner side of the heating clamp unit, wherein the clamp heating elements heat an outer surface of the coating on the pipeline or pipe section, and wherein

subsequently the coating sheet with the heated inner side is applied on the coating layer having a heated outer surface. The use of the heating clamp unit advantageously allows applying multiple layers of coating sheets.

In an embodiment, multiple coating layers are applied on top of each other by each time heating both the outer surface of the earlier applied coating layer and the inner surface of the next coating sheet and subsequently applying said next coating sheet onto the earlier coating layer until a desired total thickness of the coating is achieved. This way of heating provides a good bonding between the inner and outer coating sheet. In an embodiment, an initial contact location where the coating sheet contacts the pipeline or pipe section is in a central region of the support device, wherein the inflatable body bulges inward in this central region and wherein the coating sheet is initially pressed against the pipeline or pipe section in this central region, wherein an area of contact subsequently spreads out on either side of this central region and travels along the circumference of the pipeline or pipe section in the direction of the ends of the coating sheet, wherein the ends move toward one another and ultimately overlap one another to form a region of overlap and a seam. It was found that in this way the coating sheet is effectively positioned around the pipeline or pipe section and that the end position of the coating sheet is conformant with a target position. This way of positioning also results in a reliable positioning.

Coating sheet

The present invention further relates to a coating sheet for making a pipe coating, the coating sheet being manufactured from a thermoplastic material and having a length and a width and a square or rectangular shape.

In an embodiment, the coating sheet comprises a first main area and a second main area and weld bead area, wherein in the weld bead area the coating sheet has a thickness which is greater than the thickness of the first main area and the second main area, wherein the weld bead area is constructed to be positioned on a weld bead of a joint connecting two pipe sections. The coating sheet provides a thicker coating where it is needed, namely in the region of the weld bead which protrudes slightly from the outer wall of the pipeline or pipe section. In an embodiment, the weld bead area is in particular a band extending across the coating sheet, the band dividing the first main area from the second main area. The band advantageously covers the weld bead which typically extends around the entire

circumference of the pipeline. In an embodiment, the coating sheet has at least on chamfered end region. The chafers prevent sudden transitions in the resulting pipe coating.

SHORT DESCRIPTION OF THE FIGURES

Figure 1 shows an isometric view of a heating device according to the present invention.

Figure 2 shows an isometric view of the system according to the present invention in a pickup step. Figure 3 shows a side view of the system according to the present invention in a heating and pickup step.

Figure 4A shows an isometric view of the system according to the present invention in a first stage of a movement procedure.

Figure 4B shows an isometric view of the system according to the present invention in a next stage of a movement procedure.

Figure 5 shows a top view of the arrangement of the various parts of the system according to the present invention during the movement procedure.

Figure 6 shows a top view of the arrangement of the various parts of the system according to the present invention in a next step of the movement procedure.

Figure 7 shows a top view of the arrangement of the various parts of the system according to the present invention in a next step of the movement procedure.

Figure 8 shows a top view of the arrangement of the various parts of the system according to the present invention in a first step of an engagement procedure.

Figure 9 shows a top view of the arrangement of the various parts of the system according to the present invention during the pressing procedure in which the pipe coating is formed.

Figure 10A shows an isometric view of the arrangement of the various parts of the support device according to the present invention during the pressing procedure in which the pipe coating is formed.

Figure 10B shows another isometric view of the arrangement of the various parts of the support device according to the present invention during the pressing procedure in which the pipe coating is formed.

Figures 1 1 A and 1 1 B show a front view and a side view of a sheet according to the invention.

Figure 12 shows an isometric view of an alternative embodiment of a support device according to the invention.

Figure 13 shows an isometric view of an alternative embodiment of a heating device according to the invention.

Figure 14 shows an isometric view of another alternative embodiment of a support device according to the invention.

Figure 15 shows an isometric view of a heating clamp unit according to the present invention.

Figure 16 shows an isometric view of a the clamp heating elements of a heating clamp unit according to the present invention arranged around a pipeline. DETAILED DESCRIPTION OF THE FIGURES

The present invention relates to multiple innovative aspects associated with multiple parts. The different parts work together to form an integral system. However, these aspects and parts can be viewed independently from one another. For a proper understanding, the different aspects and parts are explained in the way they work together to form an integral system, notwithstanding the fact that they can be considered independently from one another.

Heating step

Turning to figure 1 , the system of the present invention comprises a heating device 10. With the heating device 10, a coating sheet 12 of coating material is heated to a desired temperature.

The heating device 10 has a central support 14 which extends vertically upward from a floor 16. The central support may be a frame. The heating device 10 may be positioned on board a pipeline laying vessel. A pipeline laying vessel is known in the prior art and can for instance be a J-lay vessel or an S-lay vessel. Alternatively, the heating device 10 may be positioned on shore.

The heating device comprises a plurality of heating elements 18. The heating elements 18 may be radiant heating elements. The heating elements may be infrared lamps. In top view, the heating elements are arranged in a curved shape on the central support 14, in particular in a C-shape. The heating elements 18 radiate heat outwardly, away from the central support 14.

A coating sheet 12 is positioned in an at least partially curved form and extends at least partially around the heating device 10. The coating sheet does not fully surround the heating device 10. The coating sheet 12 comprises a first end portion 51 and a second end portion 52 which are at a distance from one another. The coating sheet is shown in a heating position 22. The coating sheet is heated in this curved form. In particular in top view the coating sheet may have a shape which is similar to the arrangement of the heating elements 18. Other configurations are also possible. The coating sheet Is oriented substantially vertically during the heating in case of a J-lay situation. Alternatively, in S-lay or for coating a pipe section on shore, the orientation of the heating device may be horizontal. For reel-lay, the pipeline or pipe section may be horizontal, vertical or inclined during the coating operation. Turning to figures 1 1A and 1 1 B, the coating sheet 12 is typically manufactured from a thermoplastic material and has a length L and a width W. The coating sheet typically has a square or rectangular shape, but other shapes are conceivable. The coating sheet may comprise a first main area 71 and a second main area 72 and a weld bead area 73. The weld bead area 73 is a band extending across the coating sheet, the band dividing the first main area from the second main area.

The coating sheet 12 has a thickness which may lie in the order of 5-30mm. The coating sheet 12 may have a width in the order of 20-150cm and a length in the order of 60cm to 15 meter.

The embodiment of figures 1 1 A and 11 B shows a coating sheet specifically configured for coating a joint between two pipes. In the weld bead area the coating sheet has a thickness TK2 which is greater than the thickness TK1 of the first main area 71 and the second main area 72, wherein the weld bead area is positioned on the weld bead and straddles the weld bead. A transition between the first and second main area 71 , 72 and the weld bead area 73 may be gradual.

Returning to figure 1 , the coating sheet 12 has a pipeline side 21 and an outer side 20. The coating sheet 12 is heated only on the pipeline side 21 of the coating sheet. The pipeline side is brought into a softened or molten state or heated to a specific temperature range. The outer side of the coating sheet stays substantially hard (or solid) in the embodiments where only the pipeline side of the coating sheet is heated. This effectively reduces the amount of energy which is required for the coating operation and also reduces the time which is needed for the cooling off of the coating sheet after application on the pipeline or pipe section.

When the inner side of the coating sheet is heated to the required temperature, for instance to above 90 degrees Celsius, the coating sheet 12 is ready to be picked up and to be moved to the pipeline.

Engaging and pickup step

Turning to figure 2, the system 100 according to the present invention is shown. When the coating sheet 12 has been heated to the required temperature, a support device 30 is positioned around the coating sheet 12. The support device 30 may already support the coating sheet during the heating operation itself. The support device 30 is movable and is configured to move the coating sheet from the heating position 22 to the Field Joint position at the pipeline as is explained further below. The support device 30 comprises at least a first part 81 and a second part 82 which are interconnected by a hinging connection 84.

In the shown embodiment the support device 30 also comprises a third part 83. The third part 83 is connected to the second part via a second hinging connection 85. At the second hinging connection, the sheet holder 26 comprises a second intermediate part 121 B which is located between the second and third sheet holder part 26B, 26C and which is configured to be bent when the third part 83 moves relative to the second part 82.

The first part 81 and third part 83 form "doors" which can open and close. The second part 82 is a central part. The second part 82 may span a circumferential angle of about 180 degrees and the first and third part may span about 90 degrees. Together, the first, second and third part can define an annulus when the support device 30 is in the closed state. The support device comprises actuators 96, 97 with which the doors can be opened or closed.

The support device 30 comprises an at least partially curved support frame 32. The curved support frame 32 comprises a first support frame part 32A, a second support frame part 32B and a support frame third part 32C. The curved support frame may be

manufactured from steel or aluminium parts.

The support device comprises a pressing system 33 arrange on the inner side of the support frame 32. The pressing system 33 comprises an inflatable body 34 positioned on an inner side 36 of the support frame. The pressing system 33 may comprise a single inflatable body 34 or multiple inflatable bodies 34A, 34B, 34C. In case of multiple inflatable bodies, each inflatable body 34A, 34B, 34C may be associated with a respective frame part 32A, 32B, 32C.

Each of the first, second and third parts 81 , 82, 83 of the support device 30 then comprises a curved frame part 32A, 32B, 32C and an inflatable body 34A, 34B, 34C respectively associated with said frame part and connected to the inner side of said frame part. Turning to figure 12, an alternative embodiment is shown wherein the support device 30 comprises only two parts 81 , 82 which together can fully surround a pipeline. These two parts may be two semi-circular parts. Alternatively one part may be smaller than semicircular and the other part may be greater than semi-circular, as long as the two parts together can form an annular shape in order to surround the pipeline or pipe section to which the coating is to be applied.

Alternatively, the support device 30 may consist of four or five parts which together can fully surround a pipeline or pipe section.

Returning to figure 2, the first, second and third part 81 , 82, 83 are movable relative to one another from a closed position to an open position and vice versa. More in particular the first part and the third part are pivotable relative to the second part 82 about respective hinging connections 84, 85.

The coating sheet does not need to fully encircle the heating station 10 during the heating. It may be that the coating sheet only extends around 180-300 degrees around the heating station. The heating station 10 also does not need to have a same diameter as the pipeline or pipe section which is to be coated. It may be that the coating sheet has a different degree of curvature during the heating position than in the end position when it is positioned around the pipeline or pipe section.

The support device 30 comprises a pickup system 25 configured to pick up the coating sheet 12 at the heating position and to support the coating sheet during the movement procedure from the heating position to the coating position.

In the embodiment shown in fig. 2, the pickup system 25 comprises at least one sheet holder 26 in the form of a manifold body 27 arranged on the inner side of the inflatable body 34 and connected to the inflatable body 34. The manifold body 27 comprises inner air ducts 93 (indicated in dashed lines in fig. 2) and at least one outlet opening 29 which can be connected to a suction device such as an air pump. Each manifold body 27 comprises at least one suction hole 48 via which suction can be applied on the coating sheet 12. The suction holes 48 are connected to the outlet opening 29 via the inner air ducts inside the manifold body 27.

Alternatively or additionally to the manifold body 27, the sheet holder 26 may comprise a toe rest connected to a lower region of the support frame and protruding inwards below the inflatable body 34. The coating sheet 12 may then rest with its lower edge on this inwardly protruding toe rest and in this way be supported by the sheet holder.

It is noted that the coating sheet 10 is rigid enough to stay in the required shape without each part of the coating sheet being supported. In figure 2, the ends of the C-shape are not supported but will stay in position nonetheless.

The suction holes 48 may be arranged as a band which extends horizontally across the manifold body 27. The suction holes may be configured to engage an upper portion of the coating sheet 12, so that the coating sheet becomes suspended. It is also possible that the pickup system comprises suction holes 48 which are constructed and arranged to engage a bottom portion of the coating sheet 12. In particular two or three bands of suctions holes may extend horizontally across the manifold body 27. The manifold body 27 has a flat inner surface which is configured to engage the coating sheet 12. The manifold body 27 is curved and may be flexible at least near the hinging connections 84, 85. The manifold body is configured to deform when the parts 81 , 82, 83 of the support frame move relative to one another.

It is also possible that each part of the curved support frame has its own sheet holder, wherein the first curved frame part 81 has a sheet holder 26A, the second curved frame part 82 has a sheet holder 26B and the third curved frame part 81 has a sheet holder 26C. At the hinging connection 84, the sheet holder 26 has an intermediate sheet holder part 121A which is located between the first and second sheet holder parts 26A, 26B and which is configured to be bent when the first part 81 moves relative to the second part 82.

In case of a curved frame having only two hinging parts 81 , 82, each curved frame part would have its own sheet holder 26A, 26B. Also in this case, the sheet holder 26 may be a manifold body with suction holes, be a toe rest, or be a combination of a manifold body and a toe rest.

For instance a plurality of manifold bodies 27A, 27B, 27C may be provided on the inner sides of the respective curved frame parts 32A, 32B, 32C. Each part 81 , 82, 83 of the support device 30 then comprises its own manifold body 27A, 27B, 27C.

During the heating and during the engagement of the support device with the coating sheet, the doors 81 , 83 may be in an open state. In the pickup step, under pressure is created in the inner air ducts with the help of a pump (which is not part of the invention). The suction holes 48 engage the coating sheet 12 and are capable of carrying the coating sheet. The weight of the coating sheet 12 is transferred to the support device 30. The doors 81 , 83 may be temporarily closed somewhat to engage the coating sheet, and reopened once the coating sheet has been engaged.

Once the pickup step is complete the coating sheet can be moved to the coating position by the support device 30. After the support device has engaged the coating sheet and prior to the movement procedure, the doors 81 , 83 may be opened to create more room for maneuvering the support device 30 and to reduce a chance of collision between the support device 30 and the heating device 10. Moving procedure

Turning to figure 3, during the movement procedure, the support device 30 moves the coating sheet from the heating position to the pipeline or pipe section to be coated. The pipeline or pipe section is at a distance from the heating position. The pipeline 40 has an upper pipe section 41 which is welded to a lower pipe section 42 at the weld 67. When the present invention is used in J-lay on board a pipelay vessel, the pipeline 40 extends substantially vertically.

The movement procedure may be a three dimensional movement. The support device 30 comprises drives and actuators to carry out this movement.

The support device 30 comprises actuators 79 for moving a holding section 74 of the support device 30 upward relative to the base 75. The holding section 74 comprises the first, second and third part 81 , 82, 83, the sheet holder 27 and the pickup system 25. Turning to figures 4A, 4B and 5, the support device is first moved upward to lift the coating sheet upward and away from the heating device. The support device 30 may be in the open state during the moving procedure.

The support device 30 may comprise a base 75 having wheels 76. The wheels are driven by a drive 94. Tracks 77 are provided on a floor 78 of the installation vessel near the pipeline. The tracks extends between the heating device 10 and the pipeline 40.

Alternatively, overhead rails may be provided above the floor 78 and the support device 30 is suspended from the overhead rail. The support device may also be a cart having wheels 76 which simply run directly on the floor 78, i.e. without any tracks.

The support device comprises a cantilevering beam 88 which is movable in a lateral direction 89 by an actuator 90. A cross beam 91 is mounted to an end of the cantilevering beam. A central part 32B of the curved frame is mounted to the cross-beam 91.

During the moving step the coating sheet 12 is initially lifted upward from the heating device by the support device 30 in the direction of arrow 62. This is done with the actuators 79. When the coating sheet 12 is in an upper position above the heating device 10, it is free to move horizontally.

Turning to figure 6, the support device 30 subsequently moves the coating sheet 12 laterally and horizontally away from the heating device 10 in the direction of arrow 89 with the actuator 90. Next, the support device 30 moves the coating sheet horizontally in the direction of arrow 63 with the drive 94.

Next, the support device 30 moves the coating sheet downward in the direction of arrow 64 (shown in figure 3). In another embodiment, the heating device 10 may be positioned lower than the

Field Joint Area 15. In that case, the coating sheet 12 is first lifted upward. Once the coating sheet is in the upper position above the heating device, the coating sheet can be moved in a single horizontal direction to the Field Joint position. In such an embodiment, there is no need to lower the coating sheet in the direction of arrow 63.

Turning to figure 7, the support device 30 subsequently moves the coating sheet horizontally toward the pipeline or pipe section 40 in the direction of arrow 64.

The coating sheet 12 stays in a curved form during the movement from the heating position to the Field Joint position. The first and third parts (or doors) 81 , 83 of the support device 30 are in the open position during the movement.

Positioning and pressing

Turning to figure 8, the support device 30 subsequently moves the coating sheet 12 laterally toward the pipeline or pipe section 40 until the part of the coating sheet 12 which is held by the central part 82 engages with the pipeline or pipe section. The Field Joint area 15 extends around the pipeline and extends vertically to both sides of the weld 67. The weld has a weld bead 68. The support device may comprise actuators for rotating the holding section relative to the base 75 in three directions. In J-lay, the pipeline 40 or pipe section need not be exactly vertical but may extend at an angle to the vertical. The holding section 74 is rotated to become aligned with the pipeline 40 or pipe section.

Turning to figures 9, 10A and 10B, subsequently the first part 81 and third part 83 of the support device are closed with the actuators 96, 97 in order to complete an annulus and let the coating sheet 12 extend fully around the pipeline 40 or pipe section . The curved frame parts 32A and 32C pivot about the hinging connection 84, 85 in order to close the annulus.

A first end region 51 and a second end region 52 of the coating sheet meet one another and form a seam 53. The first and second end region 51 , 52 overlap in a region of overlap 57. The seam 53 extends parallel to the pipeline axis 54.

A single coating sheet 12 fully surrounds the Field Joint Area, thereby fully covering the pipeline.

Subsequently, the curved frame parts 32A, 32C are locked with locking devices 122.

Next, the inflatable body 34 (or multiple inflatable bodies) is inflated with a fluid by a pump. The fluid may be a gas or a liquid. The coating sheet 12 is pressed against the pipeline or pipe section by the pressure of the inflated body 34. The inflating procedure may start in a central region 150 of the second part 82. To this end, the location of the entry 151 of the air or other medium may be located in this region. The central region is the region which is located at a farthest position from the ends 153, 154 of the inflatable body. The coating sheet is initially pressed against the pipeline or pipe section in this central region first. The inflatable body 34 bulges inward between points "A" and "B" as indicated in dashed lines in figure 10A. The coating sheet engages the pipeline or pipe section between points "C" and "D" as indicated in figure 10A. Next, the coating sheet is pressed against the pipeline or pipe section on either side of this central region 150. The area of contact spreads out on either side of these points "C" and "D" and travels along the circumference of the pipeline or pipe section in the direction of the ends 51 , 52 of the coating sheet 12. As a result, the ends 51 , 52 move toward one another and ultimately overlap one another to form a region of overlap 57 and a seam 55 as is shown in figure 10B.

The inflatable bodies are maintained under pressure during a cooling off period in order to let the heat of the inner side of the coating sheet dissipate and to let the inner side solidify. During the solidification, the coating sheet 12 bonds to the pipeline 40 or pipe section.

Furthermore, the first and second end region 51 , 52 are connected to one another by pressing with the support device 30 and letting the previously applied heat form the connection between the first and second end region.

The support device 30 may comprising multiple inflatable bodies positioned on the inside of the support frame. In that case the support device comprises a filling system 99 configured to inflate the inflatable bodies at different pressures.

Retracting step

In a next step, the sheet holder 27 is released. In case of suction holes 48, the under pressure is removed. The inflatable body is deflated so that sheet holder 27 comes loose from the coating sheet.

Next, the doors 81 , 83 are opened and the support device 30 is retracted from the pipeline or pipe section. The pipe coating is now completed. The pipeline is then ready to be lowered and a next step in the pipeline laying cycle may commence. For materials with adequate thermal conductivity, the invention offers also the advantage of being able to install the coated FJ into sea without having to quench it. The outer side of the consumable being not heated, its mechanical resistance is improved compared to existing art.

The support device 30 is now ready to start a new cycle. During the positioning and pressing step, a new coating sheet may have been heated at the heating station 10.

Obviously this is only possible if two or more support devices 30 are provided. Alternatively, a separate support construction for supporting the coating sheet 10 at the heating station may be provided. Although the present invention disclosure describes the making of a field joint coating comprising a coating layer of plastic which is molten on the inner side, it should be understood that the field joint coating may comprise multiple layers. For example, there may be an additional layer of primer or fusion bonded epoxy applied on the steel pipeline or pipe section prior to applying the coating sheet 12 and adhesive layers may be applied between any of the layers in the system to promote adhesion.

Further embodiment

Turning to figures 13 and 14, a further embodiment according to the present invention is shown. The embodiment relates to applying pipe coatings on individual pipe sections. This embodiment may in particular be useful for applying pipe coatings on so called "singles", which are pipe sections having a length of 12 meter. The ends of the pipe section may be left without coating, allowing a subsequent welding operation for welding the pipe sections in an end-to-end relationship into longer pipe sections or welding the pipe sections into a pipeline.

In this embodiment, the coating sheet 12 will be substantially larger than a coating sheet for coating a joint and the coating sheet 12 will typically not have a thickened weld bead area 73.

This embodiment may be based on a heating device which is oriented horizontally and on a pipe section which has a horizontal orientation during the application of the coating sheet onto the pipe section.

The heating device 10 has a horizontal frame 14. Radiant heating elements 18 are mounted on the frame 14. The frame 14 itself is supported by a first and second post 200, 201. The coating sheet 12 is positioned around the heating device 10. The coating sheet 2 may have a C-shape. The heating of the coating sheet takes place in a same way as in the embodiment of figure 1.

Turning to figure 14, the support device 30 of this embodiment is similar to the support device shown in figure 2 with a few notable differences. First, it is longer and may have a length of 12 meter. Further it has a horizontal orientation. It is noted that the present invention is not limited to coating individual pipe sections in a horizontal orientation and the pipe section may be coated in an upright orientation. The suction holes 48 in the sheet holder 26 may be arranged in a different configuration. For instance, the suction holes 48 may be arranged in horizontal rows. Other patterns are also possible. Turning to figures 15 and 16, the present invention further includes the possibility of applying multiple coating sheets on top of one another until the desired thickness of the coating is achieved.

A heating clamp unit 250 is provided which is configured to be positioned around a coated pipeline 40 or pipe section. The heating clamp unit 250 is known per se and comprises clamp heating elements 252 arranged on an inner side of the heating clamp unit.

The clamp heating elements 252 are configured to heat an outer surface of a coating on the pipeline or pipe section.

The heating clamp unit 250 itself may comprise three parts 254A, 254B, 254C which are interconnected by two hinging connections 256A, 256B. The heating elements are arranged along an inner side 258 of the movable parts. 254A, 254B, 254C. The skilled person will recognize that a heating clamp unit 250 with only two movable parts 252A, 252B is also possible. In use, prior to positioning the pre-heated coating sheet 12 around the pipeline or pipe section with the support device 30, the heating clamp unit 250 is positioned around the coated pipeline 40 or pipe section. The clamp heating elements 252 heat an outer surface 260 of the coating on the pipeline or pipe section. Subsequently the next coating sheet with the heated inner side is applied on the coating layer having the heated outer surface 260.

During the cooling period, the two coating layers bond with one another. The heated outer side of the earlier coating sheet bonds with the heated inner side of the next coating sheet.

In this way, multiple coating layers are applied on top of each other by each time heating both the outer surface of the earlier applied coating layer and the inner surface of the next coating sheet and subsequently applying said next coating sheet onto the earlier coating layer until a desired total thickness of the coating is achieved. For instance, 3, 4, 5, 6, 7, 8 or more coating layers can be applied on top of one another.

General remarks

It is noted that one particular way of moving the coating sheet from the heating position to the coating position is disclosed, but that several other embodiments are possible. For instance, the support device 30 may be mounted on a forklift or other type of vehicle. The support device 30 may also be mounted on an overhead crane. The support device 30 may also be mounted on a robot arm having a fixed base. The transport drive 94 would then be the drive of the vehicle, the drive of the overhead crane or the drive of the robot arm. Various ways of moving the coating sheet from the heating position to the coating position are possible.

Furthermore, it is possible that a storage position is created as an intermediate position between the heating device 10 and the coating position. The storage position may be located between the heating position and the coating position. The support device can be positioned in the storage position prior to being moved to the coating position. This creates space at the heating device and allows a next sheet to be heated by the heating device.

Therefore, several configurations are possible, both onshore and on a pipelay vessel.

Naturally, on a pipelay vessel the available space is somewhat limited and efficient use will need to be made of the available space. The term remote position covers both the heating position and the storage position and may also cover a treatment position in which another treatment of the coating sheet is carried out.

It is also possible that multiple heating devices are provided to further increase the speed of coating.

It will be clear that the method according to the invention will generally be carried out on a pipeline installation vessel during a pipeline laying operation. The method of pipelay may in particular be J-lay. In J-lay the coating sheet is held substantially vertically throughout the process.

However, instead of making Field joint Coatings, the present invention can also be used to make longer sections of pipe coating, in particular the main pipe coating on single joints. These pipe coatings may have a length in the order of 12 meter. In this embodiment the support device also has a length (or height) of 12 meters.

It will be recognized that an embodiment may not achieve all of the stated objects.

As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. Further, the terms and phrases used herein are not intended to be limiting, but rather, to provide an understandable description of the invention.

The terms "a" or "an", as used herein, are defined as one or more than one. The term plurality, as used herein, is defined as two or more than two. The term another, as used herein, is defined as at least a second or more. The terms including and/or having, as used herein, are defined as comprising (i.e., open language, not excluding other elements or steps). Any reference signs in the claims should not be construed as limiting the scope of the claims or the invention.

The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Claims

Support device (30) configured for holding a pre-heated coating sheet (12) and moving the pre-heated coating sheet from a remote position at a distance from a pipeline or pipe section to a coating position on the pipeline (40) or pipe section, the device comprising:

- a support frame (32) comprising at least a first curved frame part (32A) and a second curved frame part (32B) which are movable relative to one another between an open state and a closed state, wherein in the open state the first and second curved frame part define an opening (95) for a pipeline or pipe section, wherein in the closed state the first and second curved frame part surround a cylindrical volume which is configured for accommodating the pipeline or pipe section,

- at least one sheet holder (26) arranged on an inner side of the support frame and supported by the support frame, the at least one sheet holder being configured to engage the pre-heated coating sheet and support the preheated coating sheet on an inner side of the support frame during the movement of the support frame,

- a transport drive (94) configured for moving the support frame in the open state from the remote position to the coating position,

- a frame part actuator (96, 97) for moving the first curved frame part and

second curved frame part relative to one another from the open state to the closed state for bending the pre-heated coating sheet which is held by the at least one sheet holder around a circumference of the pipeline or pipe section

- a pressing system (33) arranged on an inner side of the curved frame parts, the pressing system being configured to press the pre-heated coating sheet against the pipeline or pipe section, wherein the pressing system is configured to apply the coating sheet on a Field Joint area (15) where two pipe sections (41 ,42) are joined together in an end-to end relationship, wherein the applied coating sheet extends on both sides of the joint.

Support device according to claim 1 , wherein the sheet holder comprises a first sheet holder part (26A) having a shape of a part of a cylinder and connected to the first curved frame part and a second sheet holder part (26B) having a shape of a part of a cylinder and connected to the second curved frame part.

3. Support device according to claim 1 , wherein the pressing system comprises one or more inflatable bodies (34) which are constructed to be inflated from an empty state to a filled state for pressing the pre-heated coating sheet against the pipeline or pipe section once the device is in the closed state and surrounds the pipeline or pipe section.

4. Support device according to any of the preceding claims, wherein the at least one inflatable body (34) is positioned on a pipeline side of the support frame and wherein the at least one sheet holder (26) is arranged on an inner side of the inflatable body.

5. Support device according to claim 3 or 4, wherein the inflatable body (34) has an at least partially curved shape, in particular the shape of a part of a cylinder.

6. Support device according to any of the preceding claims, wherein the first curved frame part (32A) and the second curved frame part (32B) are interconnected by a hinging connection (84).

7. Support device according to any of the preceding claims, wherein the support frame comprises at least a third frame part (32C), wherein the third curved frame part is pivotable relative to the second curved frame part (32B) via a second hinging connection (85).

8. Support device according to any of the preceding claims, wherein the at least one sheet holder (26) comprises a manifold body (34) comprising an internal air duct, an outlet opening (29) and suction members (48).

9. Support device according to any of the preceding claims, wherein a first sheet holder (26A) is connected to the first curved frame part (32A) and a second sheet holder (26B) is connected to the second curved frame part (32B), or in case of a support frame comprising three curved frame parts (32A, 32B, 32C), a first sheet holder (26A) is connected to the first curved frame part (32A), a second sheet holder (26B) is connected to the second curved frame part (32B) and a third sheet holder (26B) is connected to the third curved frame part (32B).

Support device according to any of claims 1-9, wherein the at least one sheet holder (26) is indirectly connected to the support frame via the pressing system (33).

1 1. Support device according to any of the preceding claims, comprising a base (75) which is movable on tracks (77) by the drive (94), an actuator (79) for moving a support section (74) comprising the first part (81), second part (82) and third part (83) up and down, and an actuator (90) for moving the support section (74) in a lateral direction.

12. Method for holding a pre-heated coating sheet (12) and moving the pre-heated

coating sheet (12) from a remote position at a distance from a pipeline or pipe section to a coating position on a pipeline (40) or pipe section, the method comprising:

- engaging the pre-heated coating sheet in a remote position by at least one sheet holder (26) of the support device (30) according to any of the preceding claims, wherein a first sheet part (12A) is held in a first curved shape by a first curved frame part (32A) and a second sheet part (12B) is held in a second curved shape by a second curved frame part (32B), wherein the first and second curved frame part hold the pre-heated coating sheet in an open state which defines an access for the pipeline or pipe section,

- moving the support frame in the open state by the transport drive (94) from the remote position to the coating position at the pipeline or pipe section, - moving the first curved frame part and the second curved frame part relative to one another from the open state to the closed state by the frame part actuator (96, 97), wherein the pre-heated coating sheet is bent around the circumference of the pipeline or pipe section and engages a circumference of the pipeline or pipe section and forms a cylindrical pipe coating, wherein the coating sheet is applied on a Field Joint area (15) where two pipe sections

(41 , 42) are joined together in an end-to end relationship, wherein the coating sheet extends on both sides of the joint.

13. Method according to preceding claim, wherein the pre-heated coating sheet is

supported in an open state prior to moving the coating sheet to the coating position, wherein the coating sheet comprises a first sheet part (12A) which has the shape of a part of a cylinder and a second sheet part (12B) which has the shape of a part of a cylinder, said first and second sheet part being connected by an intermediate sheet part, wherein the coating sheet comprises a first end portion (51 ) and a second end portion (52) which in the open state are at a distance from one another, the method comprising folding the pre-heated coating sheet around the pipe section or pipeline and letting the first end portion (51) and second end portion (52) engage one another.

14. Method according to any of the preceding claims 12-13, wherein the intermediate sheet part forms a living hinge and is bent during the bending of the sheet around the pipeline or pipe section.

15. Method according to any of the preceding claims 12-14, the method comprising

pressing the pre-heated coating sheet with a pressing system (33) against the pipeline or pipe section during a pressing time period (T2), during which pressing time period an adhesion of the coating sheet to the substrate is achieved and the coating sheet cools off.

16. Method according to any of the preceding claims 12-15, wherein the pressing system (33) comprises one or more inflatable bodies (34), wherein the one or more inflatable bodies are inflated from an empty state to a filled state and press the coating sheet (12) against the pipeline or pipe section.

17. Method according to any of the preceding claims 12-16, the method comprising

pressing the pre-heated coating sheet against the pipeline or pipe section according to a pre-established pressure-time curve during which the pressure is varied.

18. Method according to any of the preceding claims 12-17, wherein the pressure is applied on the pre-heated coating sheet in different pressure zones by associated different inflatable bodies, and wherein the pressure in a first pressure zone is different from the pressure in a second pressure zone.

19. Method according to the preceding claim, wherein a layer of fusion bonded epoxy (FBE) is applied to the pipeline or pipe section and wherein a layer of adhesive is applied onto the FBE prior to the moving of the pre-heated coating sheet to the coating position.

20. Method according to any of the preceding claims 12-19, wherein the first and second curved frame part are locked around the pipeline or pipe section with a locking device (122) prior to the pressurization step.

21. Method according to any of the preceding claims 12-20, wherein the coating sheet has an inner, pipeline side (21) and an outer side (20), and wherein the coating sheet is pre-heated before being moved to the coating position, wherein the coating sheet is pre-heated only on the pipeline side of the coating sheet, wherein the pipeline side is brought into a softened or molten state, wherein the pipeline side is subsequently pressed against the pipeline in the pressing step.

22. Method according to any of the preceding claims 12-21 , wherein the pre-heated

coating sheet is moved from the remote position to the coating position in a vertical orientation.

23. Method according to any of the preceding claims 12-22, wherein the at least one sheet holder comprises suction members (48) and wherein the coating sheet is supported by applying suction on the coating sheet by the suction members.

24. Method according to any of the preceding claims 12-23, wherein after the bending step a single pre-heated coating sheet (12) fully surrounds a circumference of the pipeline or pipe section (40).

25. Method according to any of the preceding claims, , wherein the joint is formed by a J- lay installation on board a pipeline laying vessel.

26. Method according to any of the preceding claims 12-25, wherein during the bending step the curvature of the coating sheet is changed, in particular by pivoting the first curved frame part (32A) relative to the second curved frame part (32B), wherein the coating sheet is wrapped around the pipeline, wherein a first and second end region (51 , 52) of the coating sheet meet one another and form a seam (53).

27. Method according to claim 26, wherein the first and second end region (51 ,52)

overlap.

28. Method according to the preceding claim, wherein the first and second end region are connected to one another by pressing them onto one another with the pressing device and letting the previously applied heat form the connection between the first and second end region.

29. Method according to any of the preceding claims 12-28, wherein at least one edge (55) in the end region of the coating sheet is chamfered.

30. Method according to the preceding claim, wherein the coating sheet comprises a first main area (71) and a second main area (72) and a weld bead area (73), wherein in the weld bead area the coating sheet has a thickness which is greater than the thickness of the first and second main areas, wherein in the positioning step the weld bead area is positioned on a weld bead (68) on the pipeline or pipe section, wherein the weld bead area is in particular a band extending across the coating sheet dividing the first main area from the second main area.

31. Method according to any of the preceding claims 12-30, wherein the method is

carried out on a pipeline installation vessel during a pipeline laying operation, wherein the method of pipelay is in particular J-lay and wherein the coating sheet is held substantially vertically throughout the process.

32. Method according to any of the preceding claims 12-31 , wherein the method is

carried out on a pipe section on shore.

33. Method according to any of the preceding claims 12-32, wherein during the step of moving the pre-heated coating sheet from the remote position to the heating position the coating sheet has a curved shape and is in an open state.

34. Method according to any of the preceding claims 12-33, wherein the remote position is a heating position where the coating sheet is pre-heated.

35. Method according to any of the preceding claims 12-34, wherein during the moving step the coating sheet is lifted upward from the heating device.

36. System (100) for heating a coating sheet (12) constructed to form a coating on a pipeline (40) or pipe section, the system comprising:

- a support device (30) configured to support the coating sheet (12) in a heating position, the support device comprising a support frame (32) and at least one sheet holder (26) supported by the support frame, wherein the sheet holders are configured to collectively support the coating sheet,

- a heating device (10) comprising a plurality of heating elements (18) arranged to heat only a part of the coating sheet .

37. System according to the preceding claim, wherein the heating elements (18) are arranged to heat only one side (21 ) of the coating sheet in the heating position.

38. System according to claim 36 or 37, wherein the support device is configured to support the coating sheet in an at least partially curved form during the heating, defining an inner side (21 ) and an outer side (20) of the support sheet, and wherein the heating device is configured to heat the inner side

39. System according to any of claims 36 - 38, wherein the heating elements (18) are mounted on a central frame (14) and wherein the support device supports the coating sheet in a form in which it at least partially surrounds the heating elements, wherein the heating elements are arranged to radiate heat outwardly and radially away from the central frame (14) and toward the coating sheet.

40. System according to any of claim 36 - 39, wherein the support device is configured for moving the heated sheet from the heating position to a coating position at a pipeline or pipe section and for pressing the heated sheet against the pipeline to form the coating.

41. System according to any of claims 36 - 40, wherein the support device comprises a support frame (32) and an inflatable body (34) positioned on a pipeline side of the support frame for pressing the heated sheet against a pipeline or pipe section.

42. System according to claim 40, wherein the support frame comprises a first curved frame part (32A) and a second curved frame part (32B) adapted to extend around at least a part of the pipeline or pipe section, wherein the first curved frame part and the second curved frame part are movable relative to one another between a closed position and an open position, wherein the support device comprises a frame part drive for closing the first and second curved frame part around the pipeline or pipe section.

43. System according to any of claims 40 - 42, wherein the support device (30) is

configured to move the heated sheet from the heating position to a coating position in an at least partially curved form.

44. System according to any of claims 40 - 43, wherein a trajectory from the heating position to the coating position comprises a first trajectory part which is directed upward, wherein the support device is configured to move the heated sheet away from the heating position in the upward direction along said first trajectory part.

45. System according to any of claims 36 - 44, wherein the support device comprises at least a first curved frame part (32A) and a second curved frame part (32B) interconnected by a hinging connection (84).

46. System according to the preceding claim, wherein the support device comprises the first curved frame part (32A), the second curved frame part (32B) and a third curved frame part (32C), wherein the third curved frame part is pivotable relative to the second curved frame part via a second hinging connection (85).

47. System according to any of claims 36 - 46, wherein the heating device extends

upward from a floor (16), wherein the heating device comprises a plurality of heating elements (18), which in top view are arranged in a curved shape, in particular in a C- shape.

48. System according to any of claims 36 - 47, wherein the heating elements are radiant heating elements.

49. Method of heating a coating sheet (12) constructed to form a coating on a pipeline (40) or pipe section with the system of any of claims 36 - 48, the method comprising:

- supporting the coating sheet (12) with a support device (30) at a heating device (10),

- heating only a part of the coating sheet with the heating device.

50. Method according to the preceding claim, wherein the coating sheet has an inner side (21 ) intended to be positioned against the pipeline or pipe section and wherein only the inner side is heated, wherein the inner side is brought into a softened or molten state and wherein an outer side (20) remains in a solid state.

51 Method according to claim 49 or 50, wherein the coating sheet is supported in an at least partially curved form during the heating.

52. Method according to any of claims 49 - 51 , wherein the heating elements (18) are mounted on a central frame (14) and wherein the support device supports the coating sheet in a form in which it at least partially surrounds the heating elements, wherein the heating elements radiate heat outwardly and radially away from the central frame (14) and toward the coating sheet.

53. Method according to any of claims 49 - 52, comprising:

a. heating a part (21) of the coating sheet (12) in the heating position during a first time period (T1) with the heating device (10),

b. moving the coating sheet (12) comprising the heated part (21) from the

heating position to the pipeline or pipe section and positioning the coating sheet around the pipeline or pipe section to be coated, wherein the heated sheet engages the pipeline or pipe section and surrounds the circumference of the pipeline,

c. pressing the coating sheet against the pipeline during a second time period (T2), during which second time period an adhesion of the coating sheet to the substrate is achieved and the coating sheet cools off.

54. Method according to the preceding claim, wherein the coating sheet is pressed

against the pipeline or pipe section according to a pre-established pressure-time curve, wherein the applied pressure is measured during the pressing and wherein the pressure is maintained until pre-determined pressure values are achieved over the entire sheet or over a part of the coating sheet.

Method according to any of claims 53 - 54, wherein the pressure is applied on the coating sheet in different pressure zones by associated different inflatable bodies, and wherein the pressure in a first pressure zone is different from the pressure in a second pressure zone.

Method according to any of claims 53 - 55, wherein the coating sheet is heated and moved from the heating position to the pipeline or pipe section to be coated in a vertical orientation.

Method according to any of claims 53 - 56, wherein the heating position is located at a distance from the pipeline and wherein the support device (30) is movable and is configured to move the coating sheet from the heating position to the coating position, wherein the support device picks up the coating sheet at the heating position and holds the coating sheet during the movement from the heating position to the coating position.

58. Method according to the preceding claim, wherein the support device comprises at least one sheet holder (26) which comprises suction members (48) and wherein the coating sheet is supported by applying suction on the coating sheet by the suction members.

59. Method according to any of claims 53 - 58, wherein a single sheet (12) fully

surrounds the circumference of the pipeline (40).

60. Method according to any of claims 53 - 59, wherein during the positioning step the curvature of the coating sheet is changed by the support device, in particular by pivoting a first curved frame part (32A) and a second curved frame part (32B) relative to one another, wherein the coating sheet is wrapped around the pipeline, wherein a first and second end region (51 , 52) of the coating sheet meet one another and form a seam (53).

61. Method according to the preceding claim, wherein the first and second end region (51 ,52) overlap.

62. Method according to the preceding claim, wherein the first and second end region are connected to one another by pressing with the support device and letting the previously applied heat form the connection between the first and second end region.

63. Method according to any of claims 53 - 62, wherein the coating sheet comprises a first main area (71) and a second main area (72) and a weld bead area (73), wherein in the weld bead area the coating sheet has a thickness which is greater than the thickness of the first and second main areas, wherein in the positioning step the weld bead area is positioned on a weld bead (68) of a joint between two pipe sections, wherein the weld bead area is in particular a band extending across the coating sheet dividing the first main area from the second main area.

64. Method according to any of claims 49 - 63, wherein the support device (30)

comprises at least a first curved frame part (32A) and a second curved frame part (32B) which are interconnected by a hinging connection (84), and wherein the first curved frame part and the second curved frame part are movable relative to one another from an open state to a closed state, wherein during the positioning step the first and second curved frame part are moved into the closed state and wherein during the pressing step the support device remains closed.

65. Method according to any of claims 49-64, wherein the method is carried out on a pipeline installation vessel during a pipeline laying operation, wherein the method of pipelay is in particular J-lay and wherein the coating sheet is held substantially vertically throughout the process.

66. Method according to any of claims 490-65, wherein during the heating step the

coating sheet has a C-shape and extends at least partially around the heating device.

67. Method according to any of claims 53-66, wherein during the moving step the coating sheet is lifted upward from the heating device.

68. Support device (30) for applying pressure on a pre-heated coating sheet which is folded around a pipeline or pipe section, the support device comprising:

- a support frame (32) comprising at least a first curved frame part (32A) and a second curved frame part (32B) which are movable relative to one another between an open state and a closed state, wherein in the open state the first and second curved frame part define an opening (95) for the pipeline or pipe section, wherein in the closed state the first and second curved frame part surround a cylindrical volume which defines a pipe position and which is configured for accommodating a pipeline or pipe section,

- a pressing system (33) arranged on an inner side (36) of the first and second curved frame parts, the pressing system comprising at least one inflatable body (34), wherein the at least one inflatable body is constructed to be inflated from an empty state to a filled state for pressing the pre-heated coating sheet which is positioned on an inside of the at least one inflatable body against the pipeline or pipe section.

69. Support device according to the preceding claim, wherein in the closed state the at least one inflatable body (34) has an at least partially curved shape, in particular a shape of a part of a cylinder.

70. Support device according to claim 68 or 69, comprising multiple inflatable bodies positioned on the inside of the support frame and comprising a filling system (99) configured to inflate the inflatable bodies at different pressures.

71. Support device according to any of claims 68-70, wherein the first curved frame part (32A) and the second curved frame part (32B) are interconnected by at least one hinging connection (84), and are movable relative to one another between an open position and a closed position, wherein the at least one inflatable body moves with the first and second curved frame part, wherein the support device comprises a frame actuator (96) for closing the support device around the pipeline.

72. Support device according to any of claim 68-71 , wherein the support device (30) comprises the first curved frame part (32A), the second curved frame part (32B) and a third curved frame part (32C) interconnected by two hinging connections (84,85).

73. Support device according to any of claims 68- 72, wherein the device (30) is movable between a heating position at a heating device and a coating position at the pipeline or pipe section.

74. Support device according to any of claims 68- 73, comprising at least one sheet holder (26) arranged on the inside of the first and second curved frame parts and configured to hold the coating sheet in position during the pressurization step.

75. Support device according to claim 74, wherein the at least one sheet holder (26) is arranged on the inside of the at least one inflatable body (34), wherein the at least one sheet holder comprises in particular suction holes (48) for applying suction on an outer side of the coating sheet.

76. Support device according to any of claims 68- 75, comprising an entry (151 ) in the inflatable body (34) for entry of air or other fluid, wherein said entry is located in a central region (150) of the inflatable body which is at a farthest distance from ends (153, 154) of the inflatable body.

77. System (100) comprising:

- the support device (30) according to any of claims 68- 76,

- a heating clamp unit (250) configured to be positioned around a coated

pipeline or pipe section, wherein the heating clamp unit comprises clamp heating elements (252) arranged on an inner side of the heating clamp unit, wherein the clamp heating elements (252) are configured to heat an outer surface of a coating on the pipeline or pipe section.

78. Method of forming a coating on a pipeline or pipe section by pressing a pre-heated coating sheet (12) against the pipeline or pipe section with the device of any of claims 68-77, the method comprising:

a. positioning the pre-heated coating sheet around the pipeline or pipe section and within the support device (30) of any of claims 70-79, wherein the preheated coating sheet is positioned on an inner side of the at least one inflatable body (34),

79. Method of claim 78, wherein the pressing is performed according to a pre-established pressure-time curve during which the pressure is varied in time, wherein the pressure is measured.

80. Method according to claim 78 or 79, wherein the pressure is applied on the preheated coating sheet with a plurality of inflatable bodies.

81. Method according to any of claims 78-80, wherein the pressure is applied on the preheated coating sheet in different pressure zones by associated different inflatable bodies, and wherein the pressure in a first pressure zone is different from the pressure in a second pressure zone.

82. Method according to any of claims 78-81 , wherein a layer of fusion bonded epoxy (FBE) is applied to the pipeline or pipe section and a layer of adhesive is applied onto the layer of FBE prior to the positioning the pre-heated coating around the pipeline or pipe section.

83. Method according to any of claims 78-82, wherein the pipeline or pipe section is oriented vertically.

84. Method according to any of claims 78-83, wherein the coating is formed on board a pipeline laying vessel during a pipelay operation, wherein the vessel comprises a J- lay system or an S-lay system.

85. Method according to any of claim 78 - 84, wherein the coating is formed on shore on a pipe section and wherein the coating covers at least 80 percent of a length of said pipe section.

86. Method according to any of claims 78 - 85, wherein the pre-heated coating sheet has an inner, pipeline side (21) and an outer side (20), and wherein the pipeline side is in a softened molten state during the pressing and wherein the outer side is in a solid state during the pressing.

87. Method according to any of claims 78 - 86, wherein the pre-heated coating sheet is wrapped around the pipeline, wherein a first and second end region (51 , 52) of the coating sheet meet one another and form a seam (53).

88. Method according to any of claims 78 - 87, wherein the first and second end region (51 ,52) overlap.

89. Method according to the preceding claim, wherein the first and second end region (51 , 52) are connected to one another by pressing with the support device and letting the previously applied heat form the connection between the first and second end region.

90. Method according to any of claims 78-89, wherein the coating sheet comprises a first main area (71) and a second main area (72) and a weld bead area (73), wherein in the weld bead area the coating sheet has a thickness which is greater than the thickness of the first and second main areas, wherein in the positioning step the weld bead area is positioned on the weld bead (68) of a joint connecting two pipe sections, wherein the weld bead area is in particular a band extending across the coating sheet dividing the first main area from the second main area.

91. Method according to any of claims 78-90, wherein the first curved frame part and the second curved frame part are movable relative to one another from an open position to a closed position, wherein during the positioning of the pre-heated coating sheet around the pipeline the first and second part are moved into the closed position.

92. Method according to any of claims 78-91 , wherein the pipeline or pipe section is

already coated with a coating layer (12), and wherein prior to positioning the preheated coating sheet around the pipeline or pipe section with the support device (30) of any of claims 200-206, a heating clamp unit (252) is positioned around the coated pipeline or pipe section, wherein the heating clamp unit comprises clamp heating elements (252) arranged on an inner side of the heating clamp unit, wherein the clamp heating elements (252) heat an outer surface (260) of the coating on the pipeline or pipe section, and wherein subsequently the coating sheet with the heated inner side is applied on the coating layer having a heated outer surface.

93. Method according to the preceding method claim, wherein multiple coating layers are applied on top of each other by each time heating both the outer surface of the earlier applied coating layer and the inner surface of the next coating sheet and subsequently applying said next coating sheet onto the earlier coating layer until a desired total thickness of the coating is achieved.

94. Method according to any of claims 78-93, wherein an initial contact location where the coating sheet contacts the pipeline or pipe section is in a central region (150) of the support device, wherein the inflatable body (34) bulges inward in this central region and wherein the coating sheet is initially pressed against the pipeline or pipe section in this central region, wherein an area of contact subsequently spreads out on either side of this central region and travels along the circumference of the pipeline or pipe section in the direction of the ends (51 , 52) of the coating sheet (12), wherein the ends (51 , 52) move toward one another and ultimately overlap one another to form a region of overlap (57) and a seam (55).

95. Coating sheet (12) for making a pipe coating, the coating sheet being manufactured from a thermoplastic material and having a length and a width and a square or rectangular shape.

96. Coating sheet (12) according to claim 95, comprising a first main area (71) and a second main area (72) and weld bead area (73), wherein in the weld bead area the coating sheet has a thickness which is greater than the thickness of the first main area and the second main area, wherein the weld bead area is constructed to be positioned on a weld bead (73) of a joint connecting two pipe sections.

97. Coating sheet (12) according to the preceding claim, wherein the weld bead area is in particular a band extending across the coating sheet, the band dividing the first main area from the second main area.

98. Coating sheet (12) according to any of claims 95 - 97, wherein the coating sheet has at least one chamfered end region (51 , 52).