Corrugated Segregating Tube for Leak-Tight Cable Terminations
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cable terminations for high voltage electrical cables face issues with maintaining steady contact between segregating equipment and the stress cone during thermal expansions and contractions, leading to potential insulating fluid leakage due to the use of rigid tubes or deteriorated tapes and gaskets.
Innovation Solution
A wet-type outdoor termination featuring a corrugated segregating tube that allows axial and radial flexibility, ensuring a steady contact between the segregating tube and the stress cone, using materials like stainless steel with different mechanical properties for the corrugated and smooth portions, and incorporating leak-tight elements to prevent fluid leakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If rigid segregating tubes are used, then structural stability is improved, but adaptability to thermal expansions and contractions deteriorates
Solution Approach 1:
The segregating tube is divided into two distinct portions: a rigid upper portion providing structural stability and support, and a flexible lower portion (with corrugated structure) that accommodates thermal expansions and contractions. This segmentation allows each portion to fulfill its specific function optimally.
Solution Approach 2:
Different portions of the segregating tube are assigned different mechanical properties: the upper portion is rigid to maintain structural stability, while the lower portion is flexible to adapt to thermal movements. This local differentiation of material properties resolves the contradiction between stability and adaptability.
2Ease of manufacture
If tapes or gaskets are used as segregating equipment, then ease of installation is improved, but reliability deteriorates due to deterioration over time
Solution Approach 1:
The invention changes the material parameter of the segregating tube from soft, deteriorable materials (tapes, gaskets) to a more durable material structure that resists deterioration from insulating fluid exposure while maintaining flexibility through the corrugated design.
Solution Approach 2:
The segregating tube combines materials with different properties: a durable base material resistant to fluid deterioration, and a corrugated structural design that provides flexibility. This composite approach maintains both ease of installation and long-term reliability.
3Manufacturing precision
If rigid segregating tubes are used, then manufacturing precision is improved, but ease of operation deteriorates during cable movements
Solution Approach 1:
The lower portion of the segregating tube is designed with dynamic flexibility through corrugation, allowing it to move and deform with cable thermal expansions and contractions while maintaining steady contact with the stress cone, thus resolving the contradiction between manufacturing precision and operational ease.
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
Maintains protection and prevents insulating fluid leakage by accommodating thermal expansions and contractions, ensuring reliable contact between the cable and stress cone, thus enhancing the durability and performance of the cable termination.
Implementation Method 1
Due to thermal variations occurring during the operative loading cycles, the electrical cable end connected to the termination maybe subjected to axial and radial expansions and contractions
Implementation Method 2
a segregating tube coaxially extending within the tubular insulation body between the stress cone and the pass-through bottom plate, surrounding and contacting at least a lower portion of the stress cone... wherein the segregating tube includes at least one corrugated portion making the segregating tube flexible
Data Source
AI summary
A wet-type outdoor cable termination can include a tubular insulation body extending along a longitudinal axis, wherein the tubular insulation body includes a main chamber configured to be at least partially filled with an electrically insulating fluid, a pass-through bottom plate mechanically connected to a lower end of the tubular insulation body, a stress cone housed within the tubular insulation body, wherein the stress cone is configured to be fitted to an end portion of an electric cable, and a segregating tube coaxially extending within the tubular insulation body between the stress cone and the pass-through bottom plate, wherein segregating tube is surrounding and contacting at least a lower portion of the stress cone and defining a safety chamber configured to partially house the end portion of the electric cable, wherein the segregating tube includes at least one corrugated portion configured to make the segregating tube flexible.