Loose-tube optical-fiber cable
The present invention relates to loose-tube optical-fiber cables that are capable of operating in high-temperature environments.
1. An optical-fiber buffer tube, comprising:
an optical fiber capable of operating at temperatures of at least about 200° C.;
a protective tube surrounding said optical fiber, said protective tube being capable of operating at temperatures of at least about 200° C.; and
a plurality of discrete deposits of adhesive material coupling said optical fiber to said protective tube, said adhesive material being capable of operating at temperatures of at least about 200° C.;
wherein the buffer tube has a buffer-tube adhesive filling coefficient of less than about 0.01.
2. The optical-fiber buffer tube according to claim 1 , wherein said optical fiber comprises a polyimide coating.
3. The optical-fiber buffer tube a according to claim 1 , wherein said optical fiber possesses low sensitivity to hydrogen.
4. The optical-fiber buffer tube according to claim 1 , wherein said protective tube comprises a nickel-chromium alloy.
5. The optical-fiber buffer tube according to claim 1 , wherein said protective tube comprises a fluoropolymer.
6. The optical-fiber buffer tube according to claim 1 , wherein said discrete deposits of adhesive material comprise silicone adhesive.
7. An optical-fiber cable, comprising:
an optical-fiber buffer tube comprising (i) an optical fiber capable of operating at temperatures of at least about 200° C., (ii) a protective tube surrounding said optical fiber, said protective tube being capable of operating at temperatures of at least about 200° C., and (iii) a plurality of discrete deposits of adhesive material coupling said optical fiber to said protective tube, said adhesive material being capable of operating at temperatures of at least about 200° C., and wherein said optical-fiber buffer tube has a buffer-tube adhesive filling coefficient of less than about 0.01;
a high-conductivity conductor;
an outer jacket surrounding said optical-fiber buffer tube and said high-conductivity conductor; and
a longitudinal strength member surrounding said outer jacket.
8. The optical-fiber cable according to claim 7 , wherein said optical-fiber buffer tube comprises (i) an optical fiber that possesses low sensitivity to hydrogen and is capable of operating at temperatures of at least about 300° C., (ii) a protective tube surrounding said optical fiber, said protective tube being capable of operating at temperatures of at least about 300° C., and (iii) a plurality of discrete deposits of silicone adhesive coupling said optical fiber to said protective tube, said silicone adhesive being capable of operating at temperatures of at least about 300° C.
9. The optical-fiber cable according to claim 7 , wherein said high-conductivity conductor comprises nickel-coated copper.
10. The optical-fiber cable according to claim 7 , wherein said high-conductivity conductor is insulated with a fluoropolymer.
11. The optical-fiber cable according to claim 7 , wherein said outer jacket comprises a nickel-chromium alloy.
12. The optical-fiber cable according to claim 7 , wherein said longitudinal strength member comprises a nickel-chromium alloy and/or stainless steel.
13. The optical-fiber cable according to claim 7 , wherein said longitudinal strength member comprises:
a first layer of metal wires surrounding said outer jacket; and
a second layer of metal wires surrounding said first layer of metal wires.
14. The optical-fiber cable according to claim 13 , wherein said first layer of metal wires and said second layer of metal wires are contrahelically wrapped around said outer jacket.
15. The optical-fiber cable according to claim 7 , wherein said longitudinal strength member provides outer-tube coverage of at least about 75 percent.
16. The optical-fiber cable according to claim 7 , wherein said longitudinal strength member provides outer-tube coverage of about 95 percent.
17. The optical-fiber cable according to claim 7 , wherein the optical-fiber cable has an actual self-supporting length of at least about 5,000 feet at an operating temperature of at least about 300° C.
18. The optical-fiber cable according to claim 7 , wherein the optical-fiber cable has an actual self-supporting length of at least about 15,000 feet at an operating temperature of at least about 300° C.
19. An optical-fiber cable, comprising:
an optical-fiber buffer tube comprising (i) an optical fiber capable of operating at temperatures of at least about 300° C., (ii) a protective tube surrounding said optical fiber, said protective tube being capable of operating at temperatures of at least about 300° C., and (iii) a plurality of discrete deposits of adhesive material coupling said optical fiber to said protective tube, said adhesive material being capable of operating at temperatures of at least about 300° C., and wherein said optical-fiber buffer tube has a buffer-tube adhesive filling coefficient of less than about 0.01;
a high-conductivity conductor;
an outer jacket surrounding said optical-fiber buffer tube and said high-conductivity conductor; and
a longitudinal strength member surrounding said outer jacket and providing outer-tube coverage of at least about 75 percent;
wherein the optical-fiber cable has an actual self-supporting length of at least about 10,000 feet at an operating temperature of at least about 300° C.
20. The optical-fiber cable according to claim 19 , wherein said longitudinal strength member comprises:
a first layer of metal wires surrounding said outer jacket; and
a second layer of metal wires surrounding said first layer of metal wires;
wherein said first layer of metal wires and said second layer of metal wires are contrahelically wrapped around said outer jacket.