Multi-Layer Intumescent Fire Tape for Rapid Opening Closure

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Solution Overview

Problem

Existing fire protection strips with intumescent materials face challenges in quickly and effectively closing large openings due to the shielding effect of the foamed surface, which delays the activation of underlying layers and is exacerbated by the thermal insulation provided by adjacent walls, particularly with thin-walled pipes that melt before the intumescent material activates.

Innovation Solution

A fire protection strip with at least two layers of intumescent material, connected via a flexible means, where the heat activates the longitudinal edges to push the layers apart, increasing the surface area for heat exposure and allowing the inner layer to enter the opening, thereby creating a larger volume for foaming and quicker closure of the opening.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If a single layer of intumescent material is used, then the structure is simple, but the expansion speed is slow and the surface area exposed to heat is limited

Engineering Contradiction:
Improveexpansion speedVSAvoidstructure complexity
Core Design Contradiction:
SpeedVSDevice complexity

Solution Approach 1:

The fire protection tape is divided into multiple layers of intumescent material (at least two layers) that are flexibly connected to each other. This segmentation allows each layer to expand independently and sequentially, increasing the overall expansion speed while maintaining a relatively simple flexible connection structure between layers.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent transitions from a single-layer two-dimensional structure to a multi-layer three-dimensional structure. The layers are arranged in sequence along the thickness direction, creating a layered configuration that increases the total surface area exposed to heat without significantly increasing in-plane complexity.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Ease of manufacture

If the tape is embedded in the wall or ceiling for aesthetic reasons, then the appearance is improved, but the heat exposure area is reduced and activation is delayed

Engineering Contradiction:
Improveaesthetic appearanceVSAvoidactivation speed
Core Design Contradiction:
Ease of manufactureVSSpeed

Solution Approach 1:

The patent employs a dynamically adjustable structure where the layers can change their configuration based on temperature conditions. At normal temperatures, the layers lie flat against each other for aesthetic embedding. When heated, the layers separate and expand outward, maximizing heat exposure area and activation speed.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent utilizes temperature as a triggering parameter that changes the physical state and configuration of the intumescent material. As temperature increases, the material undergoes phase changes including softening, expansion, and layer separation, which dynamically adjust the heat exposure area and activation characteristics.

Inventive Principle:
Principle #35Parameter changes

3Ease of operation

If thin-walled pipes with low melting points are used, then installation flexibility is improved, but the pipes melt before the intumescent material activates

Engineering Contradiction:
Improveinstallation flexibilityVSAvoidfire protection reliability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The patent positions the multi-layer intumescent structure in advance around the pipe penetration, creating a pre-deployed fire barrier. The flexible connection between layers allows the structure to adapt to the pipe shape during installation, and the sequential expansion mechanism ensures rapid response when heat is detected, sealing the opening before fire can spread through the melted pipe.

Inventive Principle:
Principle #10Preliminary action

4Loss of energy

If the foamed surface shields the underlying layers, then insulation is improved, but the activation of deeper layers is delayed

Engineering Contradiction:
Improvethermal insulationVSAvoidactivation time delay
Core Design Contradiction:
Loss of energyVSLoss of time

Solution Approach 1:

By dividing the intumescent material into multiple sequentially arranged layers, the patent ensures that heat can simultaneously act on multiple layers through the flexible connections, rather than having to penetrate through already-foamed material. Each layer expands in sequence, maintaining continuous heat exposure and eliminating the time delay caused by shielding.

Inventive Principle:
Principle #1Segmentation

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 multi-layer design allows for faster expansion and quicker closure of large cross-sections, reducing smoke and fire penetration by ensuring the inner layer enters the opening before foaming, and the layers separate to prevent mutual interference, enabling a larger volume to be filled and a more effective seal than single-layer strips.

Implementation Method 1

the intumescent material expands due to the rising temperature and thus seals the opening

Methodology Applied
Scientific EffectIntumescence: Intumescent Materials

Implementation Method 2

the material foams up on this front surface

Methodology Applied
Scientific EffectThermal expansion: Thermal Expansion

Implementation Method 3

the layers are flexibly connected to each other

Methodology Applied
Scientific EffectFlexibility: Elasticity

Implementation Method 4

the heat typically first acts on the fire-resistant tape at an end face facing the fire

Methodology Applied
Scientific EffectThermal heating: Heating

Implementation Method 5

due to the insulating properties of the foamed material, it shields the material behind it from the rising temperatures

Methodology Applied
Scientific EffectThermal insulation: Thermal Insulation

Data Source

PatentEP3161362B1Fire resistant tape
Publication Date: 2019.12.04 HILTI AG
  • EP3161362B1 patent drawingFigure 1~2
  • EP3161362B1 patent drawingFigure 3~4

AI summary

A fire protection strip (22) for insertion in openings (12) in walls or ceilings (10) of buildings comprises at least two layers (24a, 24b) produced of an intumescent material, each layer (24a, 24b) having a first longitudinal edge (26a, 26b) on an outer face and a second longitudinal edge (28a, 28b) on an opposite outer face, the layers (24a, 24b) being flexibly interconnected.