Optical Fiber Cable High Friction Intermediate Layer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical fiber cables with double layer SZ stranded constructions face issues with loose buffer tubes rotating and kinking due to thermal cycles, leading to increased attenuation, especially at the reverse points of stranding, and require strong binders that can cause deformation and local pressures.
Innovation Solution
Incorporating an intermediate layer with a high coefficient of friction (>0.4) between the first and second layers of loose buffer tubes to prevent movement and rotation, using thermoplastic or thermoplastic rubber materials, and ensuring a wall thickness of 0.3-0.5 mm to maintain structural integrity and reduce attenuation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If double layer SZ stranded construction is used to increase fiber capacity, then fiber capacity is improved, but loose buffer tubes rotate and kink due to thermal cycles causing increased attenuation
Solution Approach 1:
An intermediate layer with high friction coefficient is introduced between the first and second layers of loose buffer tubes. This intermediate layer acts as a mediator that prevents relative movement and rotation between layers, thereby eliminating the cause of kinking and signal attenuation while preserving the high fiber capacity of the double layer construction.
Solution Approach 2:
The friction coefficient parameter of the intermediate layer is specifically optimized to be greater than 0.4. This parameter change ensures sufficient grip to prevent buffer tube rotation and movement during thermal cycles, directly addressing the reliability issue while maintaining the cable's structural integrity and high fiber capacity.
2Stability of the object's composition
If strong binders are used to prevent buffer tube movement, then stability is improved, but deformation and local pressures are caused
Solution Approach 1:
The wall thickness of the intermediate layer is optimized to be between 0.3-0.5 mm. This parameter change provides sufficient mechanical strength to prevent buffer tube movement and maintain stability, while avoiding excessive thickness that would cause deformation and local pressures on the buffer tubes.
Solution Approach 2:
The intermediate layer is made of thermoplastic or thermoplastic rubber materials that combine appropriate mechanical properties. These composite materials provide the right balance of flexibility and strength, preventing buffer tube movement without causing deformation, thus resolving the contradiction between stability and structural integrity.
3Reliability
If intermediate layer with high friction coefficient is added to prevent rotation, then attenuation is reduced, but cable outer diameter increases
Solution Approach 1:
The thickness of the intermediate layer is precisely controlled within the range of 0.3-0.5 mm. This parameter optimization ensures the layer is thick enough to provide sufficient friction and prevent buffer tube rotation (reducing attenuation), while remaining thin enough to minimize the increase in overall cable outer diameter.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The high friction intermediate layer stabilizes the second layer of loose buffer tubes, reducing rotations and kinks, thereby minimizing attenuation and allowing for a smaller outer diameter optical fiber cable with increased fiber capacity without deformation issues.
Implementation Method 1
an intermediate layer formed of a material having a high coefficient of friction
Data Source
AI summary
The present invention relates to an optical fiber cable, said cable comprising from the center towards the periphery: a central strength member, a first layer of loose buffer tubes stranded around said central strength member, at least one of said loose buffer tubes of said first layer containing at least one light waveguide an intermediate layer, a second layer of loose buffer tubes stranded around said intermediate layer, at least one of said loose buffer tubes of said second layer containing at least one light waveguide and a jacket surrounding said second layer of loose buffer tubes, wherein said intermediate layer is formed of a material having a high coefficient of friction.