Optical fiber cable with bonded core elements
An optical communication cable and related systems and methods are provided. The optical cable includes a plurality of wrapped core elements, and the outer surfaces of adjacent wrapped core elements are joined together by discrete bond sections. The discrete bonds sections may be structures such as laser welds, ultrasonic welds, or adhesive material. The discrete bonds hold the wrapped core elements together in the wrapped pattern, such as an SZ stranding pattern.
1. An optical communication cable comprising:
a cable body including an inner surface defining a passage in the body;
a first core element located in the cable body, the first core element comprising:
a first buffer tube having an inner surface defining a bore and an outer surface; and
a first plurality of optical fibers located within the bore of the first buffer tube;
a second core element located in the cable body, the second core element comprising:
a second buffer tube having an inner surface defining a bore and an outer surface; and
a second plurality of optical fibers located within the bore of the second buffer tube;
wherein the first core element and the second core element are wound in an SZ wrapped pattern around a central area of the passage such that the first and second core elements are adjacent to each other defining an interface between the outer surfaces of the first and second tubes, wherein the interface extends at least a portion of a length of the cable body; and
a plurality of discrete bonded sections joining the outer surface of the first buffer tube to the outer surface of the second buffer tube at discrete sections along the length of the interface, wherein the plurality of discrete bonded sections hold the first buffer tube and the second buffer tube relative to each other in the SZ wrapped pattern following winding, wherein unbonded sections of the outer surface of the first buffer tube and of the outer surface of the second buffer tube are located between adjacent bonded sections along the length of the interface.
2. The optical communication cable of claim 1 , wherein the plurality of discrete bonded sections resist normal and tangential movement between the first and second buffer tubes.
3. The optical communication cable of claim 1 , where each of the plurality of discrete bonded sections includes a center point located between first and second ends in a longitudinal direction of the interface, wherein a bond strength of each of the discrete bonded sections is greater at the center point than at the first and second ends.
4. The optical communication cable of claim 1 , wherein the plurality of discrete bonded sections comprises one to five discrete bonded sections every 25 mm of longitudinal length of the first and second buffer tube, wherein the length of each bond in the longitudinal direction of the first and second buffer tubes is less than 5 mm.
5. The optical communication cable of claim 1 , wherein the plurality of discrete bonded sections joins the first buffer tube to the second buffer tube such that between 0.5 Newtons and 1.0 Newtons is required to break the bonded sections separating the first buffer tube from the second buffer tube under a T-peel test.
6. The optical communication cable of claim 1 , wherein the discrete bonded sections maintain the first and second buffer tubes in the wrapped pattern without an external binding element applying an radially inward force.
7. The optical communication cable of claim 6 , wherein a central strength member is located in the central area of the passage, wherein the plurality of discrete bonded sections hold the first buffer tube and the second buffer tube relative to each other in the SZ wrapped pattern around the central strength member.
8. The optical communication cable of claim 1 , wherein the bonded sections are at least one of:
a laser weld fusing the outer surface of the first buffer tube to the outer surface of the second buffer tube;
an ultrasonic weld fusing the outer surface of the first buffer tube to the outer surface of the second buffer tube; and
an adhesive material located between and bonded to both the outer surface of the first buffer tube and to the outer surface of the second buffer tube.
9. The optical communication cable of claim 8 , wherein the bonded sections are formed from a material that has a color different from a color of the first buffer tube and from a color of the second buffer tube.