
QUESTION: Is this a true statement? The Outside Jacketing Process Engineer inspected the returned cable/buffer tubes and determined there was minor/normal slight binder indentation on the buffer tubes at the switchbacks from the stranding process. Minor binder indentation is a common occurrence with no negative to the fiber.
ANSWER:
The slight indentation in hard loose tubes is a normal occurrence in reverse lay stranding. As long as the indentation does not restrict the movement of the optical fibers within the tube this has no negative effect on the optical performance of the fiber. The only area where this is a problem is when reverse lay stranding (S-Z stranding) is used on 900um tight buffered designs. While the effect will not be optically noticeable immediately, over time the cold flow of the plastic can provide enough pressure to cause an attenuation increase at the indented location. If this is over the entire length of the cable it can cause problems some period of time after the cable is made and installed.
ADDITIONAL CONTENT & RESOURCES:
- Category Resource:
- Find More Information here: Technical Article: Loose Tight Buffer, Time to Define What We Mean

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