The present invention relates to a tensioner pad assembly for a track-type tensioner, comprising : a mounting support ; and a tensioner pad, mobile relative to the mounting support, said tensioner pad comprising a contact surface extending parallel to a first axis, said contact surface being able to get into contact with a pipe-like device extending parallel to said first axis.

Track-type tensioners are especially used on offshore pipelaying, to deploy elongate articles such as pipelines, cables or umbilicals. During the deployment process, the tracks exert a stretching force on the pipe or similar article, in order to control its bending. Such tensioners are described in documents US3739971 and WO2014/174287.

In order to exert a sufficient friction force, the tracks are equipped with tensioner pads providing a concave surface, adaptable to the convex surface of the pipe.

However, a fixed tensioner pad is only adapted to a certain range of pipe diameters, compatible with its concave surface. In order to lay pipes within a large range of diameters with a same tensioner, steps of replacing all the tensioner pads of the tensioner may be necessary. Such a process is long, tedious and difficult to carry out offshore.

Document WO2014/174287 discloses adjustable pads, formed by two inclined element parted by a variable distance, depending on the diameter of the pipe. Such a device nevertheless needs the intervention of the operator on each pad, in order to adjust the distance.

The present invention aims to provide a tensioner pad assembly which is auto- adjustable to the pipe diameter.

For this purpose, the invention relates to a tensioner pad assembly of the aforementioned type, wherein the tensioner pad comprise a central segment and a first and a second lateral segments, said first and second lateral segments being on each side of the central segment according to a second axis, perpendicular to the first axis, said central segment and first and second lateral segments comprising respectively a central surface and a first and a second lateral surface, said central surface and first and second lateral surfaces being part of the contact surface of the tensioner pad, each of said central segment and first and second lateral segments being translatable relative to the mounting support along a translation axis, perpendicular to the first and second axes, so that the central surface is translatable relative to the first and second lateral surfaces along said translation axis. According to preferred embodiments, the tensioner pad assembly may include one or more of the following features, considered alone or in any technically possible combination:

- each of the central surface and first and second lateral surfaces is substantially planar ; the central surface is substantially perpendicular to the translation axes ; and each of the first and second lateral surfaces is inclined relative to the central surface, so that a section of the contact surface perpendicularly to the first axis is substantially concave ;

- an angle between the central surface and the first or second lateral surface is comprised between ;

- the tensioner pad assembly comprises an adjustment device allowing the translations of the central segment and first and second lateral segments relative to the mounting support, said translations being independent to one another ;

- the adjustment device comprises a spring device associated to each of the central segment and first and second lateral segments ;

- The tensioner pad assembly comprises an adjustment device allowing the translations of the central segment and first and second lateral segments relative to the mounting support, said translations being dependent to each other ;

- the adjustment device comprises : a segment shaft fixed to each of the central segment and lateral segments ; two support shafts and fixed to the mounting support, each segment shaft and support shaft extending parallel to the first axis ; and two elbow- shaped cranks, each crank comprising two arms fixed to each other ; a junction of the arms of each crank forming a pivot with one of the support shafts, a free end of each of the arms being in contact with one of the segment shafts ;

- a free end of each of the arms comprises an oblong hole, each of said oblong holes being fitted around one of the segment shafts ;

- an external surface of a free end of each of the arms is in contact with a segment shaft ; and the adjustment device also comprises three oblong rings fixed to the mounting support, each of said oblong rings being fitted around a segment shaft ;

- the adjustment device also comprises guides able to guide a translation of the first and second lateral segments relative to the mounting support.

The invention also relates to a track for a pipe tensioner, comprising a plurality of tensioner pad assemblies as described above.

The invention also relates to a pipe tensioner comprising : a fixed structure extending along a longitudinal axis ; a plurality of tracks as described above, each track being radially mobile relative to the fixed structure ; and a radial translation apparatus associated to each track.

The invention will be easier to understand in view of the following description, provided solely as an example, and with reference to the appended drawings, wherein :

- figure 1 is a schematic, lateral view of a pipe tensioner according to a first embodiment of the invention, comprising a plurality of tensioner pad assemblies ;

- figures 2 and 3 are sectional views of a tensioner pad assembly of the pipe tensioner of figure 1 , respectively in a first and in a second configuration ;

- figures 4 and 6 are perspective views of a tensioner pad assembly, according respectively to a second and to a third embodiment of the invention ; and

- figures 5 and 7 are perspective views of parts of the tensioner pad assemblies of figures 4 and 6 respectively.

Figure 1 shows a pipe tensioner 10 according to a first embodiment of the invention. The pipe tensioner 10 is particularly designed for the deployment of a pipe 12. For example, the pipe tensioner 10 is installed on a pipelaying vessel (not shown).

The pipe tensioner 10 comprises a fixed structure 14 and a plurality of track devices 16. The fixed structure 14, intended to be assembled to a deck of said pipelaying vessel, extends along a longitudinal axis 18. The longitudinal axis 18 may be horizontal, vertical or tilted.

In the following description, an orthonormal basis (X, Y, Z) is considered, the longitudinal axis 18 being parallel to direction X.

The fixed structure 14 comprises a plurality of columns 20, parallel to and disposed around the longitudinal axis 18. Each of the track devices 16 is supported by a column 20.

The fixed structure 14 comprises at least two, and preferably four or more track devices 16, regularly disposed around the longitudinal axis 18. On the pipe tensioner 10 of figure 1 , two track devices 16 are represented.

Each of the track devices 16 comprises a track 22 and a radial translation apparatus 24. The track 22 substantially extends parallel to the longitudinal axis 18. The track 22 comprises a closed loop 26, such as a chain, rotatably movable around an elongated frame 28. An external face of the closed loop 26 bears a plurality of tensioner pad assemblies 30.

The radial translation apparatus 24 of each track device 16 is connected to the frame 28 of the track 22, and to the supporting column 20. The radial translation apparatus 24 comprises pistons extending along a radial axis, said axis connecting the supporting column 20 and the longitudinal axis 18. As shown on figure 1 , the track devices 16 are able to exert a radial pressure on the pipe 12, maintaining said pipe coaxial to the longitudinal axis 18, or to release said pipe 12 by retreating near the supporting columns 20.

Figures 2 and 3 represent a tensioner pad assembly 30 in two different configurations, in contact with pipes 12 and 1 12 of two different diameters.

Figures 4 and 6 represent tensioner pad assemblies, respectively 130 and 230, according to a second and to a third embodiments of the invention. The tensioner pad assemblies 130 and 230 are able to replace the tensioner pad assemblies 30 of the pipe tensioner 10 of figure 1 . In the following description, the tensioner pad assemblies 30, 130 and 230 are described simultaneously, the common features being designed by the same reference numbers.

The tensioner pad assembly 30, 130, 230 comprises a mounting support 32, a tensioner pad 34 and an adjustment device 36, 136, 236.

In the embodiments of figures 2, 3, 4 and 6, the mounting support 32 substantially has the shape of a plate parallel to the longitudinal axis 18. In the following description, said plate is considered to be disposed along (X, Y). One side of the mounting support 32 is able to be fixed to the closed loop 26.

The tensioner pad 34 is disposed on the other side of the plate. The tensioner pad 34 comprises a central segment 40 and a first 42 and a second 44 lateral segments, each of said segments having a cylindrical shape extending parallel to X. Each of the cylinders has a quadrilateral base.

The central segment 40 has a parallelepiped shape. The central segment 40 comprises a central surface 46, constituted by a face disposed along (X, Y) and opposed to the mounting support 32.

The lateral segments 42, 44 are on each side of the central segment 40 according to direction Y. The first 42 and second 44 lateral segments respectively comprise a first 48 and a second 50 lateral surfaces. Each of the lateral surfaces 48, 50 is plane and inclined relative to the central surface 46 by an angle a. Preferably, the angle a is comprised between 5° and 20°.

The central surface 46 and lateral surfaces 48, 50 constitute a substantially concave contact surface 52 of the tensioner pad 34. The contact surface 52 is designed for being in contact with the pipe 12, 1 12 in the configuration of the pipe tensioner 10 shown on figure 1 .

The adjustment device 36, 136, 236 allows each of the central segment 40 and lateral segments 42, 44 to be translatable relative to the mounting support 32 along a translation axis parallel to Z. In the embodiment of figures 2 and 3, the adjustment device 36 allows the central segment 40 and lateral segments 42, 44 to be translatable independently to one another. More precisely, the adjustment device 36 comprises three spring devices 60, 62, 64, connected to the mounting support 32 and respectively to the central segment 40, to the first lateral segment 42 and to the second lateral segment 44. The spring devices 60, 62, 64 may be hydraulic or pneumatic actuators.

Each of the spring devices 60, 62, 64 has a resting position (not shown) and is able to translate parallel to Z towards the mounting support 32, under a pressure on the central surface 46 or lateral surface 48 or 50. The first and second configurations of the tensioner pad assembly 30, shown on figures 2 and 3, correspond to different positions of the central surface 46 and lateral surfaces 48, 50 relative to the mounting support 32.

In the adjustment devices 136 of figure 4 and 236 of figure 6, the translations of the central segment 40 and lateral segments 42, 44 depend to each other. More precisely, the adjustment device 136, 236 comprises three segment shafts 70, 72, 74, extending parallel to X and respectively fixed to the central segment 40 and to each of the lateral segments 42, 44. The adjustment device 136, 236 also comprises two support shafts 76 extending parallel to X and fixed to the mounting support 32.

The adjustment device 136, 236 also comprises two elbow-shaped cranks 180, 280. Each crank comprises one or more sets of two arms 82, 84, fixed to each other. The two arms 82, 84 of a same crank 180, 280 form an angle β preferably comprised between 40° and 120°.

The cranks 180, 280 and shafts 70, 72, 74 and 76 are represented alone on figures 5 and 7.

A junction of the arms 82, 84 of each of the cranks 180, 280 forms a pivot with one of the support shafts 76.

In the embodiment of figures 4 and 5, a free end of each of the arms 82, 24 of the cranks 180 comprises an oblong hole 186. Each of the oblong holes 186 is fitted around a segment shaft 70, 72, 74. More precisely, one of the oblong holes 186 of each crank 180 is fitted around the segment shaft 70 of the central segment and the other oblong hole of the same crank is fitted around the segment shaft 72, 74 of each lateral segment 42,44.

In the embodiment of figures 6 and 7, an external surface 287 of a free end of each of the arms 82, 24 of the cranks 280 is in contact with a segment shaft 70, 72, 74. More precisely, one arm of each crank 280 is in contact with the segment shaft 70 of the central segment ; the other arm of the same crank is in contact with the segment shaft 72, Moreover, as shown on figure 6, the adjustment device 236 comprises three oblong rings 288 fixed to the mounting support 32. The oblong rings 288 have an oblong section perpendicular to X, said section being elongated along Z. Each of the oblong rings 288 is fitted around a segment shaft 70, 72, 74.

The adjustment device 136, 236 also comprises guides 190, 290 able to guide a translation of the lateral segments 42, 44 relative to the mounting support 32, parallel to Z. In the embodiment of figure 4, the guides 190 comprise plates perpendicular to Y, fixed on lateral sides of the mounting support 32 and able to slide against external sides of the lateral segments 42, 44. In the embodiment of figure 6, the guides 290 comprise pins fixed to the mounting support 32 and able to slide in holes of the lateral segments 42, 44.

Preferably, the adjustment devices 136, 236, in particular the shafts and cranks, are confined in a closed compartment filled with a lubricant.

An operating of the tensioner pad assembly 30 of figures 2 and 3 is as follows : as a first pipe 12, with an external surface 92 of a first diameter, is brought into contact with the contact surface 52, the spring devices 60, 62, 64 translate parallel to Z towards the mounting support 32, until each of the central surface 46 and lateral surfaces 48, 50 are in contact with a different generatrix of the external surface 92. The tensioner pad assembly 30 is in the first configuration shown on figure 2.

Preferably, the spring devices 60, 62, 64 are calibrated so that a same pressure is exerted by each of the surfaces 46, 48, 50 on a different generatrix of the external surface 92.

As the pipe 12 is parted from the tensioner pad assembly 30, the spring devices 60, 62, 64 return to their resting position.

A second pipe 1 12, with an external surface 192 of a second, bigger diameter, is then brought into contact with the contact surface 52.

In the same manner as above, the spring devices 60, 62, 64 translate parallel to Z until the external surface 192 of the pipe is in contact with each of the central surface 46 and lateral surfaces 48, 50. The tensioner pad assembly 30 is in the second configuration shown on figure 3.

As the second diameter is bigger that the first diameter, a space between the central surface 46 and the mounting support 32 is larger in the second configuration than in the first configuration. On the contrary, the lateral surfaces 48, 50 are closer to the mounting support 32 in the second configuration than in the first configuration. Therefore, the substantial concavity defined by the contact surface 52 has a bigger radius in the second configuration than in the first configuration. An operating of the tensioner pad assemblies 130, 230 of figures 4 and 6 is as follows : a pipe 12 is brought into contact with the contact surface 52 and exerts a pressure on said surface. Said pressure makes the cranks 180, 280 pivot around the support shafts 76. The oblong holes 186 or oblong rings 288, and the guides 190, 290, associate the rotating movements to a translating movement parallel to Z of the central surface 46 and lateral surfaces 48, 50. When each of said surfaces is in contact with the pipe 12, a stable equilibrium of the adjustment device 136, 236 is reached, with a same pressure is exerted by each of the surfaces 46, 48, 50 on a different generatrix of the external surface 92.

As the pipe 12 is replaced by another pipe 1 12 with a different diameter, the adjustment device 136, 236 reacts to the pressure of the pipe to reach a new equilibrium configuration.

Therefore, the contact surface 52 of the tensioner pad assemblies 30, 130, 230 is able to automatically adapt to the shape of the pipes 12, 1 12 within a large range of diameters.

An operating of the tensioner 10 for the laying of a pipe 12 will now be described. As the track devices 16 are in a retracted position, a pipe 12 is brought into contact with the tensioner pad assemblies 30 of at least one of the tracks 22. All of the translation apparatuses 24 are then radially translated towards the longitudinal axis 18 until all of the tracks exert a radial pressure on the pipe 12. Upon said pressure, the tensioner pad assemblies 30 adjust to the diameter of the pipe 12, as described above. The tensioner 10 is then in the configuration of figure 1 , the pipe 12 being maintained coaxial to the longitudinal axis 18.

Then, the movement of the closed loop 26 of each track 22 around its frame 28 is actuated. The friction of the tensioner pad assemblies 30 on the pipe 12 allows said pipe to be displaced along with said tensioner pad assemblies, in one or another direction of the longitudinal axis 18.