PROTECTIVE DEVICE FOR A CABLE CONNECTION JOINT FOR A CABLE LAYING SYSTEM

Description

International Class: H02G 00 / 00 Description of the invention entitled: "PROTECTION DEVICE FOR A JOINT OF CONNECTING CABLES FOR A SYSTEM 5. CABLE LAYING" on behalf of TESMEC SpA of Italian nationality with registered office in Piazza S. Ambrogio, 16 – 20123 MILAN (MI) dep. the at no. * * * * * 10 SCOPE OF APPLICATION The present invention refers to a protection device for a cable connection joint, such as electrical conductors, ropes, or similar, for a cable laying system. In particular, the present invention refers to a device for 15 protection for a joint usable in a stretching system, for example example, of a high voltage overhead power line and in general to overhead lines which involve the so-called "braked" laying of such lines cables, or overhead conductors. STATE OF THE ART 20 In overhead line stringing plants, the current method of laying of overhead conductors, both in the case of construction of new lines, both in case of replacement of the old conductors, provides for the following operations: - positioning of the pulleys for stretching the conductor on the poles 25 that make up the route; - connection of the new conductor to a traction rope or to the conductor existing; - recovery of the traction rope or the old conductor using a winch or winch-brake storing the traction rope or the old conductor on 5 empty reels previously prepared at the winch station; - simultaneous release of the new conductor from the coil on which it is wrapped using a brake (or a winch-brake) to the brake station, to allow the “braked” tensioning of the new conductor. High voltage overhead transmission lines can be 10 composed of single conductors (one per phase), but more typically they are composed of multiple conductors for each phase, varying from 2 to 6, but with tendency to also increase up to 8 or 10 conductors. The brake and winch stations are located at opposite ends of a section of the line on which the laying or replacement of the 15 conductor. The winch station where the traction rope or the old one is recovered conductor is composed of a winch machine or brake winch for the recovery of the traction cable or the old conductor and from a number of reel rewinders equal to the number of conductors that constitute 20 each single phase of the line. On these rewinders will then be install empty reels that will collect the rope that will be reused or the "old" conductor, which will then be disposed of in special waste disposal centres recycling. The brake station where the unwinding and tensioning of the 25 new conductor (or a traction rope to be used subsequently for the tensioning of new conductors) will be composed of a brake machine and a number of coil holder stands equal to number of conductors that make up each single phase of the line. The size of the winch and brake stations is proportional to the number 5 of trestles or rewinders on which the individual reels must be housed coils. The brake winches for the recovery of the existing conductor are composed from two capstans, the diameter of which is expected to be 35 times the diameter of the driver to be recovered. 10 Normally the line subject to conductor replacement has variable lengths, but typically presents a subdivision into single operational routes, the length of which can vary approximately from 3 to 6 km, depending on the morphological characteristics of the line and the orographic conditions of the land. 15 Consequently the conductors that make up the high voltage lines have multiple interruptions along their length, due essentially due to the presence of fixed joints in the span, the so-called “mid span joints”. These have the function of connecting the two ends of the conductors when changing the coil, or when a coil runs out 20 coil of new conductor and at the beginning of the next coil. Generally the joints are composed of straight tubular cores in aluminium and / or steel with a length varying from 500mm to 2000mm. These joints cannot pass over the capstans of the brake machine, as they would break due to the bending caused by the winding on the circular surface, with the consequent catastrophic fall of the line in voltage. Therefore the joint can only be made in front of the machine brake according to the following procedure: 5 - when approaching the end of the coil, stop the brake machine and block the conductor in front of the machine with suitable clamps keep the shot on the line; - release the brake pull to let the machine take load clamp and discharge the voltage in the part of the conductor still on the 10 capstans; - connect the end of the new coil to the end of the old one coil via a flexible temporary joint (e.g. sock joint type); - recover the driver with the brake machine until the traction is released on the clamp; 15 - remove the clamp from the conductor; - resume the line pull with the winch machine until the temporary junction has passed the capstans and is in front of the brake machine; - stop the brake machine and block the driver in front of the 20 machine with clamps suitable for maintaining the tension on the line; - release the brake pull to let the machine take load clamp and discharge the voltage in the part of the conductor still on the capstans; - remove the temporary joint and make the permanent joint by 25 compression of the tubular joints on the ends of the conductors; - recover the conductor with the brake until the clamp is unloaded; - remove the clamp in front of the brake; - resume laying operations. The fixed joints in the span have dimensions and rigidity such that they do not 5 allow the passage of the same not even in the pulleys of stretching, under penalty of permanent deformation or breakage of the same, therefore the so-called "joint passes" or "joint covers" must be used, made up of tubular steel elements divided into two halves, which they completely wrap the joint itself and protect it during the 10 laying operations; these devices must however be installed before or during tensioning and must be removed when finished of the tensioning. These joint guides completely wrap around the joint while leaving freedom of movement to all the rest of the conductor, which comes out at the 15 joint ends. The joint guides currently known in the art prevent bending of the pressed aluminum joint but they cannot avoid the bend that occurs generates in the conductor at the exit of the splice when the cable, from the section straight line covered by the joint passage, resumes the configuration of the line 20 of stretching. In particular, for large diameter conductors or for conductors whose structure requires particularly large curvature radii, it is it is necessary to ensure the most gradual transition possible from the stretch straight to the free section. 25 There is therefore a need to perfect a device for protection for a cable connection joint that can exceed at least one of the drawbacks of the technique. In particular, an object of the present invention is to provide a protective device for a cable connection joint that 5 allows to effectively protect and cover the joint and at the same time time allows for the change in direction of the cable to be more gradual from the inside to the outside of said protection device or joint. A further aim of the present invention is to provide a protective device for a cable connection joint that limits 10 the curvature of the cable exiting the ends of the splice, allowing a gradual transition of the cable from the position substantially rectilinear which takes on a central section of the pass-through to the free position of the line configuration. A further aim of the present invention is to provide a 15 protective device for a cable connection joint that allows you to effectively overcome the pulleys present on the supports a cable laying system limiting the curvature of the cable in exit from the ends of said protection device or joint. A further aim of the present invention is the realisation of a 20 cable laying system comprising one or more effective protective devices for one or more cable connection joints. To overcome the drawbacks of the known art and to obtain these and further purposes and advantages, the Applicant has studied, tested and the present invention was created. 25 EXHIBITION OF THE FINDING The present invention is expressed and characterized in the claims independent. Dependent claims exhibit other characteristics of the present invention or variants of the main solution idea. In accordance with the above purposes, a device according to this 5 found protection of a cable connection joint for a cable laying system, comprises a tubular body, in particular divided into two halves, or half-shells, in which is inserted, in use, said joint. According to one aspect of the invention, said tubular body comprises one or 10 plus flexible portions configured to allow, in use, a flexion of said device. By means of this protection device, which is bendable thanks to said one or more flexible portions, it is possible to protect and cover in effectively the joint and at the same time allow to make it more 15 gradual change of direction of the cable from inside to outside of said protection device or joint guide. This protection device also limits the curvature of the cable exiting from its ends, allowing for a gradual transition of the cable from the substantially rectilinear position it assumes in a 20 central section of the protection device or joint passage to the position free of line configuration. By using this joint protection device by connecting cables it is also possible to effectively overcome the pulleys present on the supports of a cable laying system 25 reducing or limiting the curvature of the cable exiting from the ends of called protection device or joint pass-through. According to a further aspect of the invention, said one or more portions flexible ones are positioned at the ends of said tubular body. According to a further aspect of the invention, said one or more portions 5 flexible hoses extend, in use, beyond the ends of said joint. According to a further aspect of the invention, said one or more portions flexible allow a curvature of the device at the ends of a angle of approximately 10-15° with respect to the direction assumed by the cable in the central section of said protection device or joint passage. 10 According to a further aspect of the invention, said one or more portions flexible are jointed and comprise a plurality of connected rings mutually. According to a further aspect of the invention, said one or more portions flexible hoses include annular connections between said rings, 15 so as to allow for some axial movement. According to a further aspect of the invention, said rings are formed each made up of two semi-rings, which can be connected using fastening elements removable. According to a further aspect of the invention, said device comprises 20 at the ends of the cable housing tips. According to a further aspect of the invention, said tips are tubular and include a section placed internally to each of the said one or more flexible portions and equipped with a cable housing. A further object of the invention is a cable laying system, 25 equipped with at least one winch machine and at least one brake machine positioned on opposite sides with respect to one or more intermediate supports. Said system includes at least one cable connection joint provided of a protective device as defined above. ILLUSTRATION OF DRAWINGS 5 These and other aspects, characteristics and advantages of the present invention will become clear from the following description of embodiments, provided by way of example, not limitation, with reference to the attached drawings in which: - Fig. 1 is a schematic view of a cable laying system 10 according to the present invention; - fig. 1a is a view of an enlarged Z1 area of ​​the system of fig. 1, in which a protection device is schematically illustrated a cable connection joint according to the present invention; - fig. 2 is an axonometric view of the protection device; 15 - fig. 3 is a side view of the protection device; - fig. 4 is a sectional view of the device considered according to the line IV-IV of fig. 3; - Fig. 5 is a partial view of the device in one configuration flexed; 20 - fig. 6 is an axonometric view of a first part of a portion flexible device; - fig. 7 is an axonometric view of a second part of the portion flexible of fig. 6. Please note that in this description the phraseology and the 25 terminology used, as well as the figures of the attached drawings also for as described they have the sole function of illustrating and explaining better the present finding having a non-limiting exemplary function of the found itself, the scope of protection being defined by the 5 For ease of understanding, identical reference numbers are were used, where possible, to identify identical common elements in the figures. It should be understood that elements and characteristics of a form of realization can be conveniently combined or incorporated in other embodiments without further specification. 10 DESCRIPTION OF SOME EMBODIMENTS We will now refer in detail to the possible forms of embodiment of the invention, of which one or more examples are illustrated in the attached figures as a non-limiting example. Also the phraseology and terminology used here is for illustrative purposes only 15 limitations. With reference to the attached drawings, fig. 1 shows schematically a spreading system 20, according to the present found, configured to run one or more cables 11, i.e., for example, one or more electrical conductors of a high-voltage overhead line. In fig. 1, 20 by way of example and not limitation, a schematic illustration is given cable 11. The cable laying system 20 includes, for the laying of the cable 11, at least one brake machine 12 and at least one winch machine 14, each of these equipped with one or more winding organs or 25 unwinding, or capstans 13. Such brake machine 12 and such winch machine 14 could be also of the winch-brake type, or combined to carry out selectively both the winch function and the brake function. Said brake machine 12 and said winch machine 14 are positioned 5 on opposite sides to intermediate supports 15, for example pylons, on where these cables are laid 11. In the case of using machines of the type winch-brake, at least one winch-brake machine will be positioned on each side with respect to the intermediate supports. On these intermediate supports 15, as can be observed, the cable 11 is 10 stretched out on a pulley 16, or a roller track, on which, as is known, the cable 11 will be subjected to some curvature. Cable 11 is fed to the stringing system by means of at least one reel 17 placed on a stand upstream of the machine brake 12, and is recovered downstream of the winch machine 14 on 15 an additional reel 17 arranged on a rewinder. Along the laying line they are positioned as is known in itself joints for joining cable sections 11. A joint 18 is illustrated schematically in dashed lines in fig. 1a and has the purpose of joining two sections of cable 11. Said joint 18 is substantially a tubular element or 20 sleeve, to the ends of which said cable sections 11 are fixed. The said joint 18 is rigid and made of metal material. Said joint 18 is housed inside a device 10 of protection, comprising a tubular body 19, in which said is inserted joint 18. Said tubular body 19 is rigid, in particular divided into two 25 half, and made of metal material, such as steel or similar and substantially envelops said joint 18. Said tubular body 19 further preferably extends beyond the ends of said joint 18, therefore it has a greater length than the latter. Said tubular body 19 comprises one or more flexible portions 21 5 configured to allow, in use, the ends of said device 10 to bend in a controlled manner. These flexible portions 21 are in particular jointed portions. Thanks to said flexible portions 21, said device 10 is able to bend at the ends with respect to said joint 18 and said tubular body 10 19, which remain straight. This bending allows the ends of the device 10 to adapt to any changes in direction of the cable 11 in output from said device 10. In this way, any changes in direction of cable 11 exiting from the ends of said device 10 are at least partially accompanied and made more gradual by the 15 controlled curvature of said flexible portions 21. The cable 11 comes out in fact from both ends of the device 10, where they are positioned said flexible portions 21, after having exited from the ends of the joint 18. In fact, therefore, this protection device is advantageously articulated, thanks to said one or more flexible portions 20 21, especially articulated ones. In particular, see also figures 2, 3, 4 and 5, said tubular body 19 includes a flexible portion 21 at each end. Each of said flexible portions 21 extends beyond the end of the joint 18 and suitable for any change in direction of the cable 11. The device 10 25 equipped with said flexible portions 21 has a greater extension than that of said joint 18. Assuming that the cable 11 assumes a direction X inside the joint 18 and the tubular body 19, see fig. 5, said flexible portion 21 allows a curvature of the ends of the device 10 of an angle a of approximately 10-15°. 5 Said tubular body 19 comprises in particular two half-shells 19a, 19b, preferably of equal size, which are paired by means of removable fastening elements 22, so as to form a substantially cylindrical structure. Said semi-shells 19a, 19b are rigid and are made of metallic material, such as steel or similar. These are 10 fixing elements 22 are preferably recessed into the profile of the half-shells 19a, 19b, so as to avoid protrusions. Each of the flexible portions 21, in particular jointed, is formed by a plurality of rings 23 connected to each other and configured to have a certain axial reciprocal movement and to 15 allow for the controlled flexion of said portion to be achieved probeable 21, as for example in fig. 5. Substantially said rings 23 are connected to each other by annular connections 24a, 24b which allow a certain play or axial movement between said rings 23. Each of the said annular connections 24a, 24b, see in particular 20 fig. 5, 6 and 7, is essentially a tubular element provided with a tubular body 32 connected at one end to the ring 23 and equipped, at the opposite end, of an annular part 33 of external diameter greater than the external diameter of the tubular body 32. In In particular, each ring 23 comprises an annular connection 24a 25 protruding which engages with a recessed ring 24b of the next ring 23. When said annular connections 24a and 24b mutually engaged come into contact, oppose the forces of traction while still allowing for some flexion, see for example the angle a. Said rings 23 can be of equal dimensions, or 5 for example, foresee different lengths. The ring connections 24a and 24b allow for the connection of simple and effective said rings 23, allowing a certain movement reciprocal which allows the flexible portion 21 and therefore the device 10 to bend, especially at the extremities. 10 Alternatively, said flexible portion 21 could be formed also from a ball joint, a bellows element or other system that allows for some flexure of the device 10, particularly with respect to the joint 18. A ring 25 is also provided which precedes said flexible portion 21 15 and is fixed to the tubular body 19 by welding 34 or otherwise, in so as to be substantially coaxial with said tubular body 19. The said ring 25 is equipped with a protruding annular connection 24a configured to engage with the recessed 24b ring fitting of the first ring 23 of the flexible portion 21. 20 The external diameter of said rings 23 and 25 is preferably substantially equal to the external diameter of the tubular body 19, so to be avoided, at least in the rectilinear configuration, fig. 2, fig. 3 or fig. 4, radial protrusions or recesses in the device 10. Said rings 23, see in particular fig. 6 and fig. 7, are formed 25 each from two semi-rings 23a and 23b, preferably of the same shape semicircular, or similar. This allows for assembly and removal of the device 10 from the cable 11 at the end of the operations. These semi- rings 23a and 23b are joined together by means of elements removable fixings inserted flush into the relevant seats 27, so as to 5 avoid protrusions. At the ends of the device 10, in particular externally to the flexible portions 21, are positioned tips 26 that wrap the cable 11 and also have the invitation function to facilitate the entry of the said device 10 on the pulley 16. Said tips 26 are made of 10 elastomeric material, such as rubber or similar. Said tips 26 are tubular with a lateral cut to allow them to be mounted on the conductor 11; said tips comprise a section 29 placed internally to the flexible portion 21 and provided with a seat 28, fig. 4, in particular cylindrical, which embraces the cable 11, so as to protect its strands 15 external from any damage. Said section 29 positioned inside the flexible portion 21 is placed between the portion flexible 21 and the cable 11. Said section 29 comprises at the opposite end to the one where the pointed shape is obtained, a 30 ring which is placed between said ring 25 and the joint 18, so as to give stability to 20 positioning at the tip 26. Said ring 30 has an external diameter greater than that of said section 29. Said tips 26 are tightened on cable 11 using cable ties 31 or similar. It is clear that the protection device for a joint of Changes can be made to the cable connections described above 25 and / or additions of parts, without thereby departing from the scope of this found as defined by the claims. It is also clear that, although the present invention has been described with with reference to some specific examples, an expert in the field will be able to to make other equivalent forms of protective device of a 5 cable connection joint for cable laying systems, having the characteristics expressed in the claims and therefore all included within the scope of protection defined by them. In the following claims, the references in brackets have the only for ease of reading and should not be considered as 10 factors limiting the scope of protection defined by the claims same.

Claims

CLAIMS 1. Device (10) for protecting a joint (18) for connecting cables (11) for a cable laying system (20), comprising a tubular body (19) in which, in use, said joint (18) is inserted, characterised in that said tubular body (19) comprises one or more flexible portions (21) configured to allow, in use, a controlled curvature of said device (10).

2. Device (10) according to claim 1, characterised in that said one or more flexible portions (21) are positioned at the ends of said tubular body (19).

3. Device (10) according to claim 1 or 2, characterised in that said one or more flexible portions (21) extend, in use, beyond the ends of said joint (18).

4. Device (10) according to any of the preceding claims, characterised in that said one or more flexible portions (21) allow a curvature of the ends of the device (10) by an angle (a) of approximately 10-15° with respect to the direction (X) assumed by said cable (11) in a central section of said device (10).

5. Device (10) according to any of the preceding claims, characterised in that said one or more flexible portions (21) are articulated and comprise a plurality of rings (23) connected to each other.

6. Device (10) according to claim 5, characterised in that said one or more flexible portions (21) comprise annular connections (24a, 24b) connecting said rings (23), so as to allow a certain axial movement.

7. Device (10) according to claim 5 or 6, characterised in that said rings (23) are each formed by two half-rings (23a, 23b). 5 8. Device (10) according to any of the preceding claims, characterised in that it comprises at the ends tips (26) for housing the cable (11).

9. Device (10) according to claim 8, characterised in that said tips (26) are tubular and comprise a section (29) placed 10 internally to each of said one or more flexible portions (21) and provided with a seat (28) for housing the cable (11).

10. Cable laying system, provided with at least one winch machine (14) and at least one brake machine (12) positioned on opposite sides with respect to one or more intermediate supports (15), said system 15 comprising at least one cable connection joint (18) (11) provided with a protection device (10) according to any of the preceding claims.