Intumescent Foam Cable Feedthrough for Reusable Flame Sealing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing flame-tight cable bushings in rail vehicles are complex, expensive, and difficult to dismantle non-destructively, especially when structural changes are required, leading to increased effort and costs due to their inability to be reused after dismantling.
Innovation Solution
A flame-tight cable bushing with a foam seal comprising multiple concentrically arranged, detachable foam rings that can be adjusted for varying cable diameters, made from intumescent materials that expand under thermal influence, allowing for non-destructive removal and reinstallation without additional fastening means.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional flame-tight cable bushings are used to ensure flame protection, then flame-tightness is achieved, but the device complexity and manufacturing cost increase
Solution Approach 1:
The patent employs a foam seal made of intumescent material with porous structure that expands under thermal influence to maintain flame-tightness. The foam seal's cellular structure allows it to effectively block flame propagation while keeping the overall design simple and cost-effective
Solution Approach 2:
The invention uses composite construction by combining a metal bushing with a foam seal made of intumescent material. This composite approach leverages the fire-resistant properties of the foam material while maintaining the structural integrity of the metal bushing, achieving flame protection without excessive complexity
2Reliability
If conventional flame-tight cable bushings are used to ensure flame protection, then flame-tightness is achieved, but manufacturing cost increases
Solution Approach 1:
The foam seal made of intumescent porous material provides effective flame protection at lower cost compared to conventional complex bushings. The material's inherent fire-resistant properties eliminate the need for expensive complex mechanical sealing structures
Solution Approach 2:
The foam seal is designed as a replaceable, cost-effective component that can be easily installed and replaced if needed. This approach prioritizes low manufacturing cost and ease of replacement over long-term durability, allowing the inexpensive foam seal to be replaced after a fire event rather than replacing the entire bushing assembly
3Reliability
If conventional flame-tight cable bushings are used, then flame protection is provided, but adaptability for different cable diameters and design changes is reduced
Solution Approach 1:
The foam seal provides dynamic adaptability by expanding under thermal influence during fire conditions to maintain flame-tightness, while in normal conditions allowing for flexible cable installation. The concentric ring structure enables adjustment to accommodate different cable diameters
Solution Approach 2:
The foam seal is divided into concentric rings that can be detached and adjusted to accommodate different cable diameters. This segmented structure allows the same bushing to adapt to various cable sizes and facilitates easy replacement if design changes are needed
4Reliability
If conventional flame-tight cable bushings are installed, then flame protection is achieved, but ease of removal and reinstallation is worsened
Solution Approach 1:
The foam seal is segmented into concentric rings that can be easily detached from one another, allowing for simple removal of the entire foam seal assembly from the bushing. This segmented design enables non-destructive removal and reinstallation without damaging the bushing structure
Solution Approach 2:
The foam seal is designed as a separate, extractable component that can be removed from the bushing without damaging either part. This extraction capability allows for easy replacement of the foam seal while retaining the reusable metal bushing, significantly reducing dismantling effort
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 enables cost-effective and simple protection against flame spread while allowing for flexible cable installation and potential expansion, reducing assembly effort and costs associated with design changes, as the foam seal can be replaced after a fire without damaging the socket.
Implementation Method 1
it expands further under thermal influence, especially in the event of a fire. The foam material is therefore an intumescent material.
Data Source
Figure 1~2
Figure 3
AI summary
A flame-resistant cable gland (100) comprises a socket (110) with a through-opening (113) for guiding at least one cable (300) through a partition (200), and a foam seal (120) made of a foam material for insertion into the through-opening (113) of the socket (110) and for enclosing the at least one cable (300). The foam seal (120) has at least two concentrically arranged foam rings (121, 122, 123) that are detachable from one another for stepwise adjustment of the clear inner diameter of the foam seal (120), wherein the foam material corresponds to building material class B1 or B2 according to DIN 4102:1998 and expands under thermal influence, in particular in the event of a fire.