Armored Optical Cable Bonding to Prevent Fiber Axial Shifting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Optical fibers in armored cables used for downhole oil and gas monitoring are prone to axial shifting, leading to optical loss and potential fracture due to mechanical stress, and existing methods for preventing this are costly and complex.
Innovation Solution
An armored cable design where optical fibers are adhered to the inner wall of the armor tubing using an adhesive material, with guide tubes protecting the fibers during welding and support legs preventing contact with the adhesive, ensuring secure attachment and reduced strain.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If optical fibers are loosely placed in armored cable, then ease of manufacture is improved, but axial shifting occurs causing optical loss and potential fracture
Solution Approach 1:
The patent applies preliminary action by pre-attaching optical fibers to the inner wall of the armor tubing before the cable is deployed. The adhesive material is applied to the inner wall in advance, and fibers are positioned and secured before final cable assembly, preventing axial shifting from occurring during installation and use.
Solution Approach 2:
The patent uses an adhesive material as an intermediary substance between the armor tubing inner wall and the optical fibers. This adhesive mediator creates a secure bond that prevents axial shifting while maintaining the structural integrity of both the tubing and fibers, resolving the contradiction between loose placement and secure attachment.
2Reliability
If guide tubes are used to protect fibers during welding, then reliability is improved, but device complexity increases
Solution Approach 1:
The patent applies the taking out principle by removing the guide tubes after they have served their protective function during welding. The guide tubes are temporarily inserted to protect fibers from welding damage, then extracted once welding is complete, leaving a simpler final cable structure without permanent guide tube components.
Solution Approach 2:
The guide tubes are discarded after serving their temporary protective purpose during the welding process. This allows the system to gain the reliability benefit of fiber protection during manufacturing while avoiding the permanent complexity increase that would result from incorporating guide tubes as permanent cable components.
3Reliability
If adhesive material is applied to inner wall, then axial shifting is prevented, but manufacturing precision requirements increase
Solution Approach 1:
The patent applies partial action by positioning optical fibers to contact the adhesive material at specific locations on the inner wall rather than requiring uniform contact along the entire fiber length. This selective adhesive contact provides sufficient prevention of axial shifting while reducing the precision requirements compared to full-surface bonding.
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 solution effectively prevents axial shifting of optical fibers, reduces optical loss, and simplifies the manufacturing process by minimizing components, enhancing the reliability and cost-effectiveness of fiber optic cables for downhole applications.
Implementation Method 1
optical fibers are adhered to the inner wall of the armor tubing using an adhesive material
Implementation Method 2
welding a seam of the armor tubing in a welding zone
Data Source
AI summary
Certain aspects of the present disclosure provide techniques for making armored cables. An example method for making an armored cable includes forming a strip stock into an armor tubing; welding a seam of the armor tubing in a welding zone; inserting at least one of a first optical fiber or a first wire into a first end of a first guide tube, wherein: the first guide tube extends through the welding zone; the first guide tube protects the at least one of the first optical fiber or the first wire during the welding of the seam; and the first guide tube is not part of the armored cable after the making of the armored cable; and supporting the first guide tube within the armor tubing by a plurality of support legs such that the first guide tube does not contact the armor tubing.