Termination arrangement for an overhead electrical cable
A termination arrangement for securing an overhead electrical cable to a dead-end structure such as a dead-end tower. The termination arrangement includes a compression sheath that is configured to be disposed between a strength member and the conductive strands of the overhead electrical cable. The compression sheath mitigates damage to the strength member that may occur when an outer metallic sleeve is compressed around the conductive strands and the conductive strands are compressed against the strength member. The arrangement is particularly useful for securing overhead electrical cables having a composite strength member to a dead-end structure.
1. A termination arrangement securing an overhead electrical cable to a dead-end structure, the overhead electrical cable having a composite strength member and conductive strands surrounding the composite strength member, the termination arrangement comprising:
a connector anchoring the termination arrangement to a dead-end structure;
a gripping element secured by the connector and gripping the composite strength member at a proximal end of the overhead electrical cable;
an outer metallic sleeve surrounding at least the gripping element and the proximal end of the overhead electrical cable, the outer metallic sleeve having a compressed portion disposed over the proximal end of the overhead electrical cable; and
a compression sheath disposed between the composite strength member and the conductive strands along at least the length of the conductive strands under the compressed portion.
2. The termination arrangement recited in claim 1 , wherein the composite strength member comprises reinforcing fibers disposed within a binding matrix.
3. The termination arrangement recited in claim 2 , wherein the binding matrix is a metallic matrix.
4. The termination arrangement recited in claim 2 , wherein the binding matrix is a polymeric matrix.
5. The termination arrangement recited in claim 4 , wherein the polymeric matrix comprises a polymer selected from a thermoset resin polymer and a thermoplastic polymer.
6. The termination arrangement recited in claim 2 , wherein the reinforcing fibers comprise fibers selected from the group consisting of carbon fibers, boron fibers, metal oxide ceramic fibers, glass fibers, carbide fibers, aramid fibers and basalt fibers.
7. The termination arrangement recited in claim 6 , wherein the reinforcing fibers comprise carbon fibers.
8. The termination arrangement recited in claim 1 , wherein the composite strength member comprises a plurality of individual composite rods that are operatively combined to form the composite strength member.
9. The termination arrangement recited in claim 1 , wherein the composite strength member consists essentially of a single composite rod.
10. The termination arrangement recited in claim 1 , wherein at least a portion of the conductive strands have a cross-sectional shape that is polygonal.
11. The termination arrangement recited in claim 1 , wherein at least a portion of the conductive strands have a cross-sectional shape that is non-polygonal.
12. The termination arrangement recited in claim 11 , wherein the conductive strands that have a non-polygonal cross-sectional shape have a cross-sectional shape that is substantially circular.
13. The termination arrangement recited in claim 11 , wherein at least a portion of the conductive strands having a cross-sectional shape that is substantially circular are in direct contact with the compression sheath.
14. The termination arrangement recited in claim 1 , wherein the conductive strands comprise copper strands.
15. The termination arrangement recited in claim 1 , wherein the conductive strands comprise aluminum strands.
16. The termination arrangement recited in claim 15 , wherein the conductive strands comprise hardened aluminum strands.
17. The termination arrangement recited in claim 1 , wherein the compression sheath does not extend substantially beyond the compressed portion of a distal end of the termination arrangement.
18. The termination arrangement recited in claim 1 , wherein the compression sheath is a closed cylindrical tube that is sized and shaped to slide over the strength member.
19. The termination arrangement recited in claim 1 , wherein the compression sheath is a cylindrical tube having a slot along a length thereof to facilitate placement of the compression sheath over the composite strength member.
20. The termination arrangement recited in claim 1 , wherein the compression sheath is structurally independent from the composite strength member.
21. The termination arrangement recited in claim 1 , wherein the compression sheath is fabricated from a material selected from the group consisting of a metallic material, a polymeric material, and a composite material.
22. The termination arrangement recited in claim 21 , wherein the compression sheath is fabricated from a metallic material.
23. The termination arrangement recited in claim 22 , wherein the compression sheath is fabricated from aluminum.
24. The termination arrangement recited in claim 23 , wherein the compression sheath is fabricated from hardened aluminum.
25. The termination arrangement recited in claim 1 , wherein the compression sheath has a thickness of at least about 0.20 mm.
26. The termination arrangement recited in claim 1 , wherein the compression sheath has a thickness of not greater than about 2.6 mm.
27. The termination arrangement recited in claim 1 , wherein the connector comprises an eye bolt.
28. The termination arrangement recited in claim 1 , wherein the termination arrangement further comprises a jumper plate.
29. The termination arrangement recited in claim 1 , wherein the gripping element comprises a collet that is compressed to grip the composite strength member.
30. The termination arrangement recited in claim 29 , wherein the collet is disposed within a collet housing.
31. The termination arrangement recited in claim 30 , wherein the collet housing is operatively attached to the connector.
32. The termination arrangement recited in claim 1 , wherein the compression sheath comprises a proximal portion and a distal portion, wherein the distal portion is disposed between the composite strength member and the conductive strands and the proximal portion surrounds a portion of the composite strength member that extends beyond the proximal end of the overhead electrical cable.
33. The termination arrangement recited in claim 32 , wherein the proximal portion of the compression sheath has a larger outer diameter than an outer diameter of the distal portion of the compression sheath.
34. The termination arrangement recited in claim 33 , wherein the distal portion of the compression sheath is disposed within a cavity formed in the connector.
35. A method for securing an overhead electrical cable to a dead-end structure, the overhead electrical cable having a composite strength member and conductive strands surrounding the composite strength member, the method comprising:
placing a compression sheath between the composite strength member and the conductive strands at a proximal end of the overhead electrical cable;
placing an outer metallic sleeve over at least the proximal end of the overhead electrical cable and the compression sheath; and
compressing at least a portion of the outer metallic sleeve onto the conductive strands.
36. The method recited in claim 35 , wherein the compressing step comprises applying a pressure of at least about 15 tons to the outer metallic sleeve.
37. The method recited in claim 35 , further comprising the step of securing a proximal end of the composite strength member to a connector.
38. The method recited in claim 37 , further comprising the step of anchoring the connector to a dead-end structure.
39. A kit comprising components that are configured to be assembled into a termination arrangement for securing an overhead electrical cable to a dead-end structure, the overhead electrical cable having a composite strength member and conductive strands surrounding the composite strength member, the kit comprising:
a connector configured to anchor the termination arrangement to a dead-end structure;
a gripping element configured to be secured by the connector and to operatively grip the composite strength member at a proximal end of the overhead electrical cable;
an outer metallic sleeve configured to surround at least the gripping element and the proximal end of the overhead electrical cable; and
a compression sheath configured to be disposed between the composite strength member and the conductive strands along at least the length of the outer metallic sleeve.
40. The termination arrangement recited in claim 26 , wherein the compression sheath has a thickness of at least about 0.5 mm.
41. The method recited in claim 35 , wherein the compression sheath has a thickness of at least about 0.2 mm.
42. The method recited in claim 35 , wherein the compression sheath is fabricated from aluminum.
43. The method recited in claim 35 , wherein the compression sheath is a cylindrical tube having a slot along a length thereof to facilitate placement of the compression sheath over the composite strength member.
44. The kit recited in claim 39 , wherein the compression sheath is a cylindrical tube that is sized and shaped to slide over the strength member.
45. The kit recited in claim 39 , wherein the compression sheath is a cylindrical tube having a slot along a length thereof to facilitate placement of the compression sheath over the composite strength member.
46. The kit recited in claim 39 , wherein the compression sheath has a thickness of at least about 0.2 mm.
47. The kit recited in claim 39 , wherein the compression sheath is fabricated from aluminum.