Honeycomb Intumescent Firestop for Stable Insulating Crust

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Solution Overview

Problem

Existing fire protection elements with intumescent materials fail to maintain a stable insulating crust during a fire, leading to limited protection time as the crust becomes unstable and burns down.

Innovation Solution

A fire protection element with a molded part featuring a honeycomb structure made of intumescent material, which expands to form a cross-linked, stable crust, combined with a flexible filling foam and a frame for enhanced stability and smoke-tight closure, allowing for longer-lasting fire protection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If intumescent material is used to form an insulating crust, then fire protection is provided, but the crust becomes unstable and falls down after a while

Engineering Contradiction:
Improvefire protectionVSAvoidcrust stability
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The molded part is divided into multiple honeycomb cells, each acting as an independent chamber that contains and supports the intumescent material. This segmentation prevents the formation of a large, unstable crust by distributing the expansion across multiple smaller, contained spaces with rigid walls.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The honeycomb structure provides localized rigid support at the walls of each cell, while the intumescent material fills the interior spaces. This creates a composite structure where the rigid honeycomb walls provide structural stability while the intumescent material provides fire protection, with each component performing its specialized function.

Inventive Principle:
Principle #3Local quality

2Stability of the object's composition

If the molded part is made rigid to maintain structure, then stability is improved, but flexibility for compression and adaptation to openings is reduced

Engineering Contradiction:
Improvestructural stabilityVSAvoidadaptability to openings
Core Design Contradiction:
Stability of the object's compositionVSAdaptability or versatility

Solution Approach 1:

The honeycomb structure exhibits dynamic mechanical properties: under low stress it maintains its rigid shape for structural stability, but under compression it allows the cells to collapse in a controlled manner, enabling the molded part to be compressed and adapted to different opening sizes while maintaining structural integrity when installed.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The thin walls of the honeycomb cells act as flexible elements that can deform under compression forces during installation, allowing the overall structure to be compressed. Once installed, these same walls provide rigid support to maintain the structural stability of the fire protection element.

Inventive Principle:
Principle #30Flexible shells and thin films

3Duration of action of stationary object

If the crust is made thicker to extend protection time, then fire protection duration is improved, but the weight and volume of the element increase

Engineering Contradiction:
Improveprotection timeVSAvoidelement weight
Core Design Contradiction:
Duration of action of stationary objectVSWeight of stationary object

Solution Approach 1:

The honeycomb structure segments the intumescent material into multiple cells, creating a high surface-area-to-volume ratio. This allows the material to expand and form protective layers more efficiently throughout the volume, extending fire protection duration without requiring a proportional increase in overall material quantity, weight, or volume.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The combination of the honeycomb structural material and the intumescent material creates a composite fire protection element. The honeycomb structure provides mechanical support and thermal insulation, while the intumescent material provides active fire protection through expansion. This composite approach achieves extended protection time with optimized weight and volume by leveraging the complementary properties of both materials.

Inventive Principle:
Principle #40Composite materials

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 honeycomb structure and frame design create a stable, cross-linked crust that provides extended fire protection, while the flexible filling foam ensures smoke-tight and soundproof closure, improving the element's durability and adaptability.

Implementation Method 1

the expandable graphite particles are activated by the heat on the surface, expand towards the fire and initially form an insulating crust

Methodology Applied
Scientific EffectIntumescent expansion: Thermal Expansion

Implementation Method 2

the honeycomb structure is filled with a filling foam. The filling foam ensures a smoke-tight closure of the opening through the fire protection element

Methodology Applied
Scientific EffectFoam filling: Foam

Data Source

PatentEP3586050B1Fire retardant element
Publication Date: 2023.09.13 HILTI AG
  • EP3586050B1 patent drawingFigure 1
  • EP3586050B1 patent drawingFigure 2
  • EP3586050B1 patent drawingFigure 3

AI summary

The invention relates to a fire protection element (100) for the separation of openings passing through walls or ceilings, in particular of line passages, comprising a molded part (112) with a honeycomb structure (114) made from intumescent material.