Double-Wall Cabin Separation Structure with Mineral Wool

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing double-wall separation structures with air gaps in ship cabins face a trade-off between weight reduction and maintaining adequate noise reduction capacity, with conventional solutions compromising on either mechanical strength or acoustic performance.

Innovation Solution

A double-wall separation structure using mineral wool with a fibred structure and specific density and airflow resistivity, combined with a metal sheet of defined thickness, to achieve comparable noise reduction to traditional rock wool solutions while reducing the overall weight of the panels.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Weight of moving object

If traditional rock wool is used in double-wall separation structures with air gaps, then noise reduction capacity is maintained, but weight of panels increases

Engineering Contradiction:

Improveweight of panelsVSAvoidnoise reduction capacity

Core Design Contradiction:

Weight of moving objectVSObject-affected harmful factors

Solution Approach 1:

The patent changes the density parameter of the soundproofing material from traditional rock wool (typically 120-200 kg/m³) to mineral wool with density between 80-120 kg/m³. This parameter change achieves weight reduction while maintaining adequate noise reduction capacity through optimized material selection and formulation.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent employs composite material construction by combining mineral wool soundproofing material with specific metal sheet materials (steel or iron alloy) in a layered panel structure. This composite approach allows optimization of both weight and acoustic performance through material synergism.

Inventive Principle:

Principle #40Composite materials

2Weight of stationary object

If panel mass is reduced to save weight, then weight of ship construction decreases, but noise reduction capacity deteriorates

Engineering Contradiction:

Improveweight of ship constructionVSAvoidnoise reduction capacity

Core Design Contradiction:

Weight of stationary objectVSObject-affected harmful factors

Solution Approach 1:

The patent optimizes the density parameter of the soundproofing material to fall within 80-120 kg/m³, which is lower than traditional rock wool density. This parameter optimization enables weight reduction of the ship construction while maintaining the required noise reduction capacity between adjacent cabins.

Inventive Principle:

Principle #35Parameter changes

3Weight of moving object

If lighter soundproofing material is used, then panel weight decreases, but mechanical strength may be compromised

Engineering Contradiction:

Improvepanel weightVSAvoidmechanical strength

Core Design Contradiction:

Weight of moving objectVSStrength

Solution Approach 1:

The patent creates a composite panel structure combining mineral wool with metal sheets (steel or iron alloy) where the metal component provides mechanical strength while the mineral wool provides soundproofing. This composite construction resolves the contradiction between weight reduction and strength maintenance.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent applies different material properties to different parts of the panel: metal sheets provide structural strength and rigidity, while mineral wool provides acoustic insulation. This local differentiation of material functions allows simultaneous optimization of strength and weight.

Inventive Principle:

Principle #3Local quality

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 structure achieves an apparent sound reduction index of not less than 43 dB, comparable to traditional systems, while significantly reducing the weight of cabin panels, thereby addressing the need for lighter ship construction without compromising on noise insulation or mechanical strength.

Implementation Method 1

a layer of soundproofing material (4), associated to a second face (3b) of the metal sheet (3)... the soundproofing material comprises mineral wool

Methodology Applied

Scientific EffectAcoustic absorption: Acoustic Absorption

Implementation Method 2

two partition walls (W1, W2) facing opposite one to the other, that belong to the perimetric structure of two different cabins (C1, C2) and are separated by an air gap (30)

Methodology Applied

Scientific EffectAcoustic isolation: Acoustic Absorption

Data Source

PatentEP3261910B1Separation structure between two cabins with double wall and air gap, in particular between passenger cabins

Publication Date: 2020.10.14 FINKANTIERI SPA

Figure 1~3
Figure 4
Figure 5~8b

AI summary

A separation structure between two adjacent cabins (C1, C2), comprising two partitions (W1, W2) facing opposite one to the other, separated from each other by an air gap (30). Each partition wall consists of at least one partition panel (2, 20) comprising: at least a first metal sheet (3) made of an iron alloy and a thickness between 0.5 and 0.9 mm; at least one layer of soundproofing material (4) associated to the metal sheet. The soundproofing material comprises mineral wool having a fibred structure with a content of non-fibred material of less than 1% by weight, an apparent density between 80 and 120 kg/m3 and a resistivity to airflow between 50 and 300 kPa s/mi. The layer of soundproofing material has a thickness between 12 and 28 mm.. The structure has an apparent sound reduction index R'w between the two adjacent cabins of not less than 43 dB ±1 dB. A panel of such a structure, a passenger ship with such a structure and the use of said soundproofing material are also described.