Risers and other types of continuous tubulars are widely used for connecting a subsea manifold at an oil or gas wellhead to a surface structure such as an FPSO. Handling reels of wound riser, or other elongate members such as umbilicals, cables, flow lines, flexible pipe etc is difficult as a typical reel can be 9m in diameter, and can weigh several hundred tonnes. Generally a reel needs to be delivered to a quayside for loading onto the ship, and lifted by crane from its cradle and placed on an under roller so that the reel can be rotated about its axis as the riser or other flexible member is loaded from the reel onto a basket or another reel on board ship. Lifting the reel onto the under roller requires a large crane. Also, unloading reels for inspection and/or repair of the elongate member is equally problematic.

According to the present invention there is provided apparatus for handling a reel with an arcuate outer surface, the apparatus comprising a roller device to engage the arcuate outer surface of the reel, and a driver device to move the roller device relative to the reel in order to move the reel.

Typically the reel is lifted by movement of the rollers'towards one another on one side of the arcuate surface.

Typically a pair of rollers are provided, one of each side of the arcuate outer surface. More than one pair can be provided in preferred embodiments, so that on a large reel, or where the reel has more than one arcuate surface, a pair of rollers can be provided for each arcuate surface of the device.

Further pairs of rollers can be provided as required.

The driver device can comprise a hydraulic ram, and typically each roller device has a respective hydraulic ram to move it relative to the others. It should be noted that in simple embodiments of the invention, is not necessary for all of the roller devices to move relative to one another, or relative to the reel being lifted, but it is sufficient for a single movable roller to move relative to a fixed roller. Indeed, in some embodiments one or more of the rollers can be substituted for, or can simply bear against, stationary shoulders against which the movable roller (s) can push the arcuate surface.

However, in preferred embodiments of the invention, each roller is movable, and typically has a respective driver associated with it. In certain embodiments, a single driver device can drive all (or some) of the movable rollers by means of a belt or similar transmission system known in the art.

Typically, the rollers are placed on opposing sides of the arcuate outer surface of the reel and are driven towards one another by means of the hydraulic ram so as to travel around the arcuate surface and force the reel upwards relative to the apparatus.

In preferred embodiments, the reel being lifted bears a wound riser or the like, and the raising of the reel by means of the rollers allows the reel to be disengaged from its carrying cradle, and rotated around its axis in order to unwind the riser from the reel, or to wind it on.

In typical embodiments of the invention, the roller device and the driver device are mounted on a frame, which can typically be constructed around the reel to be lifted.

In certain embodiments, the apparatus can incorporate a conveyor such as an endless track conveyor, or a crawler. track. The conveyor can comprise wheels in simple embodiments of the invention.

The present invention also provides a method of handling a reel with an arcuate outer surface, the method comprising engaging at least one side of the arcuate outer surface of the reel with at least one roller device, and moving the roller device in order to move the reel.

The present invention also provides a method of handling a reel, the method comprising constructing a frame around the reel, the frame comprising a conveyor, and moving the reel by means of the conveyor.

This forms a very useful part of the invention as a reel laid on a cradle or on the ground can simply have a frame constructed around it in accordance with this aspect and then lifted and/or moved to another location without requiring a crane. Since embodiments of the invention can be constructed in locations where crane access is difficult this construction or assembly of the frame around the reel etc permits many useful advantages. In some embodiments the reel is lifted before being moved to another position by the conveyor; however, the reel can simply be pulled by the conveyor in some cases, or can be lowered from a cradle or other mounting onto the frame once it has been assembled in place around the reel.

An embodiment of the present invention will now be described by way of example and with reference to the accompanying drawings,-in which: Fig la shows a schematic plan view of handling apparatus; Fig 1b shows a close up of the ram arrangement on Fig la ; Figs 2 and 3 show plan views of a second apparatus with additional components; Fig 4 shows side and end detailed views of the fig 2 and 3 apparatus; Fig 5 shows a schematic part end view of the fig 2 and 3 apparatus; Fig 6 shows a detailed view of part of the fig 5 apparatus; Fig 7 shows a schematic view of handling apparatus with an additional hydraulic ram; Fig 8 shows a side view of a conveyor; Fig 9 shows a plan view of a further handling apparatus; Figs 10,11 and 12 show sequential side views of a reel being handled on the fig 9 apparatus; Fig 13 shows a plan view of the fig 9 apparatus, with a lifting frame in place; Fig 14 shows an end view of the Fig 13 assembly; Fig 15 shows a different plan view of the fig 9 apparatus with a lifting frame in place; and Fig 16 shows an end view of the fig 15 assembly.

Referring now to fig 1, handling apparatus for lifting a reel upon which is wound a subsea riser comprises four roller devices 3 which are each mounted on an axle set in bearing blocks 4, and are rotated around their axles by motors 5. In the embodiment shown, each roller 3 has a respective motor 5, but in certain embodiments, all of the rollers 3 can be driven by a single motor, or only one or two of the rollers 3 can be driven, with the others idling. The assembly of the roller 3, bearing blocks 4, and motor 5 is in each case mounted on a carriage 10. Each carriage 10'can slide perpendicularly to the axis of the axles on the upper surface of a pair of beams 15o/15I at one end of the beams 15, while the other carriages 10 are fixed to the other end of the beams 15.

Along with cross pieces 17, the beams 15 form the sides of a frame with the crosspieces bolted or otherwise attached to the ends of the beams 15. The carriages 10'each have an end wall at their outermost ends, and can travel parallel to the beams 15 for short distances. The rollers 3 engage the arcuate flanges of a reel 30 at 4 locations on the circumference. The reel 30 can be rotated around its main axis while supported by the rollers 3, and the motors 5 can drive this rotation through their rotation of the rollers 3.

The ends of the beams 15 have shoulders 11 facing the end walls of the carriages 10', and the space between the end wall and the shoulder in each case can accommodate a hydraulic ram 25. The rams 25 can be extended in order to drive the carriages 10'away from the shoulders 11 of the beams 15, so that the distance between the rollers 3 decreases and the rollers 3 move around the arcuate circumference of the reel 30, thereby lifting the reel 30.

Referring now to Figs 2 and 3, a similar handling apparatus 2 has similar components that will be labelled accordingly, but differs from the apparatus 1 in that there are extended cross pieces 17'that extend beyond the beams 15. The outermost beams 15o are straight, but the innermost beams 15i have indents at their central portions, inwards of their straight end surfaces that are parallel to the outer beams 15o along which the carriages 10 can slide.

Also, all of the carriages 10 on the apparatus 2 can slide and are pushed by rams 25 towards one another.

Endless track devices 20 are optionally attached to the frame of the apparatus 2 via a respective pair of chassis rails 18 mounted parallel to the side beams 15, and located on either side of each endless track device 20. As shown in fig 5, the chassis rails 18 are coupled to the body of the endless track devices 20, which are placed alongside the side beams 15. Bolt tensioning devices 23 are provided on the chassis rails and lifting tendons 24 are connected through the chassis rails between the bolt tensioning devices 23 and the cross pieces 17 of the handling frame. Once the lifting tendons 24 have been connected to the cross pieces 17, the bolt tensioning devices 23 can be activated in order to pull the lifting tendons 25 upwards, as will be described later. In some embodiments, a single jack can be arranged to lift a plate connected to several (e. g. 4) lifting tendons, which can spread the load of the jack more evenly on the frame.

In use, the frame comprising the side beams 15 and cross pieces 17'is built around a stationary reel 30 resting on a cradle 31. Fig 4 shows the reel 30 lying on different types of cradle 31 in each of figs 4a/b, c/d and e/f. In each case, the side beams 15i are placed on the inside of each flange of the reel 30, and the side beams 15o are placed on the outside of each flange. The beams 15 are then connected to the cross pieces 17', using bolts or any other suitable means, and the carriages 10 are then placed on the flat end surfaces on top of the beams 15'between the arcuate surface of the flanges and the shoulders 11 on the beams 15. At this point, the frame comprising the beams 15 and cross pieces 17'can be disposed on the same surface as the cradle, without engaging the reel 30 or the cradle 31.

After the beams 15 have been connected to the cross pieces 17', and the carriages bearing the assembly of the rollers 3, bearing blocks 4, and motors 5 have been placed on the top surface of the beams 15 between the end shoulders 11 and the flanges of the reel 31, the hydraulic rams 25 (omitted from Fig 4 for clarity but visible in other figures) are located between the shoulders 11 and the end walls of the carriages 10. The rams 25 are then extended so as to push the carriages 10 inwards along the flat end surfaces of the beams 15 towards one another so that they engage the arcuate outer surfaces of the flanges of the reel 30.

The rollers 3 typically have flanges at their outer edges, and optionally also have inner flanges so that the flanges of the reel 30 can be received on the roller 3 between the two flanges on the rollers, thereby preventing the flange of the reel from becoming dislodged from the roller 3.

Once the flange of the reel 30 has been engaged at each opposing side by a respective roller 3, and is located between the flanges of each roller 3, the reel 30 is safely engaged with the handling apparatus. Continued pressure on the hydraulic rams 25 at this point pushes the rollers 3 towards one another, and since each roller 3 is in contact with the outer surface of the flange of the reel, eventually pressure from the hydraulic rams 25 overcomes the weight of their reel 30 and lifts the reel 30 from the cradle 31. Not all of the rollers 3 need to be driven by rams 25, but this can distribute the load of the rams and the rollers evenly, and is therefore preferred. This permits maximum torque to be applied through the rollers.

Once the reel 30 is free of the cradle 31, the motors 5 can rotate at least one of the rollers 3 in order to rotate the reel 30 around its axis and this permits winding and unwinding of the riser from the reel. This exemplifies one aspect of the invention in permitting lifting and rotation of a reel 30 on a one-piece apparatus, thereby avoiding the previous requirement to lift the reel from its cradle onto an under roller using a crane.

The optional provision of low ground pressure crawler tracks 20 on either side of the beams 15 provides an opportunity to construct a single piece of apparatus to move the reel 30 around the quayside and permit unloading from the same apparatus. Once the hydraulic rams 25 have pushed the carriages 10 inwards so that the rollers 3 engage the reel 30, the crawler tracks 20 can be attached to the frame of the apparatus while it is still on the ground and before the reel 30 has been lifted by compression of the rollers 3.

As mentioned above, the chassis rails 18 of the crawler track module are located parallel to the side beams 15 of the frame and on either side of a crawler track unit 20. While the frame is still on the ground, the bolt tensioning devices 23 pull the lifting tendons 24 upwards in order to lift the entire frame of the apparatus, including the reel 30 engaged on the rollers 3, clear of the ground. It will be appreciated that other types of lifting devices can be substituted for the bolt tensioning devices. Once the frame and reel 30 are disengaged from the ground, the tracks 20 can be used to drive the reel 30 to the required position on the quayside.

In one embodiment of the device shown in fig 7, an endless grommet sling can be attached between a lifting rim on the reel 30 and a sheave on the side beams 15, which is connected to a hydraulic ram to pull down the sheave thereby increasing the force applied to the rollers 3 by the reel 30. This can help in increasing the traction between the reel 30 and the rollers 3, and is especially useful when the reel 30 is being loaded with riser, as typically the bending forces involved can tend to disengage the reel 30 from the rollers 3. The grommet sling also helps to stop the bending and tension forces of the pipe, and the vessel motion, from lifting the reel from the cradle during handling.

In the embodiment shown in Fig 3, cross-braces 40 are provided in the form of tensioned cables extending between opposing corners of the frame.

The cables 40 help to stabilise the frame when being transported by e. g. conveyor tracks, which would otherwise tend to force the frame into a parallelogram shape when skid steering is used. The cables 40 also brace the frame to support the weight of the reel 30 when the carriages 10 are pushed together. At that point the weight of the reel 30 rests on the rollers 3 and is transferred to the frame as the reel 30 leaves the cradle 31.

Therefore the cables 40 give the frame lateral rigidity that helps the frame to withstand greater weights of reel 30.

Another embodiment of the invention shown in Fig 9 is similar to the first embodiment, and comprises four roller devices 3 which are mounted (either slidably or by bolts) on the upper surface of a pair of beams 15o/15i at one end of the beams 15, while the other carriages 10 are fixed to the other end of the beams 15. The beams 15 are fixed together by an arcuate cradle portion 16 that is shaped to engage with the rim of the reel 30 being handled.

Along with cross pieces 17 between the roller devices, the beams 15 and cradle portion 16 form the sides of a frame that initially lies on the ground to support and to store the reel. The rollers 3 can optionally travel parallel to the beams 15 for short distances in order to lift and rotate the reel as previously described.

As shown in Figs 10-12, the reel 30 can be set down onto the cradle portions 16 of the frame, and thereafter roller devices 3 can be attached to the beams 15, and driven by rams 25 to lift the reel 30 as shown in Fig 12. The reel 30 can then be loaded with the pipe etc, being rotated by the optional motors on the roller devices 3, and then set back down onto the cradle portions 16. At that point the rollers 3 and rams etc can be removed so that the reel rests only on the cradle portion 16, which can then travel with the reel 30. If desired, the reel 30 can be stabilised on the cradle portion 16 by chocks (not shown) placed at the positions formerly occupied by the rollers 3. Alternatively the rollers 3 can simply remain in place or the reel can be tied to the cradle portion 16 e. g. by means of a grommet sling as previously described.

When the loaded reel + frame is to be moved, a conveyor frame 18/19 can be built around it in situ as shown in figs 13-14. The conveyor frame 18/19 comprises conveyor tracks 20 as previously described attached to a rigid frame 18/19 built around and above the reel-carrying frame 15/17, which remains on the ground as shown in fig 14. When the conveyor frame 18/19 is assembled, jacks on the upper conveyor frame 18/19 lift tendons that are connected to the reel-carrying frame 15/17, and lift it with the reel off the ground until the two frames are secured together and the reel-carrying frame 15/17 is clear of the ground. The whole assembly can then be driven by means of the tracks 20 to a suitable location, without requiring a crane. The reel 30 can either be carried with its axis perpendicular to the direction of travel as shown in Fig 13 and 14, or with it's axis parallel to the direction of travel, as shown in figs 15 and 16.

Thus the invention also provides a transport cradle that can be adapted with roller devices to turn the reel, and drivers to lift it, and which can be incorporated into a frame to transport the assembly of the reel and the cradle, or alternatively moved by conveyors such as endless track devices.

Modifications and improvements can be incorporated without departing from the scope of the invention.