WCA March 2019

3.1 Lobe separation In addition to being able to separate the optical lobe using easily accessible technology, the customer requested the ability to be able to separate the optical and twisted-pair lobes using only a pair of standard-issue side cutters versus a previously used lobe separation tool costing over $100 per installer. This customer request required a balance of a thinner web section of the cable and cable integrity through mechanical testing such as twist, impact and real-world installations. There is also a complicating factor of extruding a tight jacket on the optical lobe to ensure water penetration performance and at the same time extruding a loose jacket on the twisted-pair lobe to achieve an easy pull off of the twisted-pair lobe jacket during cable access. Through the use of flow modelling and precision tool manufacturing, all aspects of lobe separation and solutions for the difficult extrusion process were met. 3.2 Optical fibre access The end of the cable at the pole was pre-connected in the factory, but the end at the premises needed to be accessed in the field. This was done with basic installation tools and no need for a ripcord or razor blades when accessing the outer jacket. This is becoming more prevalent for premium cables in the telecommunications industry, but it is difficult to achieve a proper location with a design having asymmetric lobe designs and having requirements for a tight pressure extrusion setup on one lobe and a loose tubing extrusion setup on another lobe. 3.3 Clamp As the ability to manufacture the specified cable type became more feasible, the cable development team was tasked to work with clamp manufacturers to design and develop a new drop wire cable clamp. This clamp would need to perform the typical functions of a clamp by holding the cable to a pole or side of the premises without slipping. In addition, the same clamp needed to keep the fibre from being pulled into the span and causing attenuation in the fibre connector at the pole and inside the premises. This has previously been done with a clamp and separate fibre-coupling device, but in this case, the task was to incorporate cable clamping and fibre coupling into one device. Standard industry clamps trying to achieve this were not suitable for this cable design. This was done by using the equation ( Figure 3 ) and empirical testing to determine the length of the clamp, lay length and number of turns. The clamp prevented any fibre tension in the span from transferring to the connector and ultimately held the cable past the breaking strength (almost three times environmental loading). 4 Conclusions A customer’s multiple design requirements can often contradict each other, but a good understanding of those

( in radians) o - T o - e = T out in

(Clamp)

(connector or house side)

T

in

T out

(span side)

❍ ❍ Figure 3 : Equation

requirements along with close collaboration and honesty where requirements may need to be prioritised can and did lead to a successful product launch. 5 Acknowledgements We thank all of those before us who worked internally on development of high-precision extrusion tooling. They made this design possible along with project teams, production staff and personnel, and the commercial group. Special thanks to Neil Abernathy, Larry Barrett, Dale Blevins, Dave Chiasson, Jeff Dellinger, Keith Lail, Hanna Marciniak, Narien Penley and Beaver Williams. 6 References [1] M Gimblet, G Abernathy, J Lail, and C Queen, “Simple Tools + Safe Methods = Minimal Effort by Design,” International Wire & Cable Symposium Proceedings of the 61 st IWCS/IICIT, presentation 3 rd to 5 th November 2012. Paper courtesy of proceedings at the 66 th IWCS Conference, Orlando, Florida, USA, October 2017

Corning Optical Communications LLC 800 17 th St NW, Hickory, North Carolina, USA Tel : +1 828 901 5000 Website : www.corning.com

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Wire & Cable ASIA – March/April 2019