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Complete analysis of centrifugal glass wool felt components

Introduction

In the "jianghu" of building insulation materials, centrifugal glass wool felt has become the "standard configuration" for industrial and civil buildings due to its lightweight, high thermal insulation and low energy consumption. Its essence is man-made inorganic fiber, which is formed by melting natural ore at high temperature and centrifugally blowing it into fibers, and then bonding and curing it with thermosetting resin. We will start with the raw material composition and reveal its "core formula".

I. "Core formula" of centrifugal glass wool felt

The ingredients of centrifugal glass wool felt can be divided into three major systems:

(I) Basic skeleton: silicate ore system (accounting for 80%-90%)

Constitutes the cornerstone of glass fiber, which is formed by melting natural ore:

Mineral Type	Chemical Composition	Core Function	Typical Proportion (of total minerals)
Quartz Sand	SiO₂ (Silicon Dioxide)	Forms the glassy network structure, determining chemical stability and high-temperature resistance	55%–65%
Limestone	CaCO₃ (Calcium Carbonate)	Adjusts melting temperature, improves mechanical strength, and durability	12%–18%
Dolomite	CaMg(CO₃)₂ (Calcium Magnesium Carbonate)	Provides MgO, enhances flexural strength, and water resistance	8%–12%

Note: The three are precisely matched in a ratio (such as SiO₂:CaO: MgO≈6:2:1) to balance the difficulty and performance of fiber melting.

(II) Functional additives: fluxing and modification system (accounting for 5%-15%)

Reduce melting temperature and optimize performance:

Soda ash (Na₂CO₃): as a "flux", reacts with SiO₂ to form sodium silicate, reducing the melting temperature from 1700℃ to 1360℃ (accounting for 3%-5%);
Borax (Na₂B₄O₇·10H₂O): provides B₂O₃, improves fiber flexibility (bending strength ↑20%+, accounting for 2%-4%);
Saline (Na₂SO₄): clarifier, eliminates melting bubbles, and ensures fiber uniformity (accounting for 0.5%-1%).

(III) Key to molding: bonding and functional system (accounting for 3%-10%)

Curing loose fibers into rolled felt:

Main binder: bio-based formaldehyde-free resin (environmentally friendly water-based epoxy resin), hot pressing and curing to form a three-dimensional network structure (accounting for 3%-8% of the finished product quality);
Functional additives: hydrophobic agent (such as silicone emulsion): make water absorption ≤0.5% (standard ≤1%); curing agent (such as hexamine): accelerate resin cross-linking; anti-aging agent (hindered amines): extend the service life to 15-20 years.

II. Safety and environmental performance

Unlike traditional asbestos, centrifugal glass wool rolled felt is certified as a non-carcinogen. Its advantages include:

Non-toxic process: the ore is melted at 1360℃ to completely decompose harmful substances;
Environmentally friendly bonding: low free formaldehyde formula (≤0.05mg/m³, better than the national standard GB 18580-2017);
Fire safety: meets Class A fire protection standards, and only shrinks when exposed to fire without releasing toxic gases.

III. Purchase and Use Guide

(I) Select parameters as needed

Key parameter recommendations for different scenarios:

Application Scenario	Recommended Density (kg/m³)	Recommended Thickness (mm)	Core Requirement
External Wall Insulation	48–64	50–100	Low thermal conductivity (≤0.038 W/m·K)
Steel Structure Roofing	16–24	50–150	High compressive strength (≥4 kPa)
Pipe Insulation	64–110	50–100	Low cost, easy to cut
Acoustic Insulation	32–120	40–100	High sound absorption coefficient (≥0.8)

(II) Identify "fake glass wool"

Beware of products impersonating mineral wool:

Index	Centrifugal Glass Wool	Ordinary Mineral Wool
Fiber Diameter	3–5 µm (fine and soft)	8–10 µm (coarse, prickly to the touch)
Thermal Conductivity	≤0.038 W/m·K	≥0.05 W/m·K
Temperature Resistance	≤400 °C (suitable for long-term use)	≤250 °C (prone to powdering, falling off, poor durability)
Environmental Friendliness	Slag-free + low formaldehyde	Contains slag, binder, recycled materials, salts, and organic substances

(III) Construction points

Cutting: Use a special wallpaper knife to avoid fiber breakage.
Splicing: Reserve 5-10mm expansion joints to prevent cracking due to thermal expansion and contraction.
Moisture-proof: Add aluminum foil veneer in humid environments to prevent moisture absorption and heat conduction.

Conclusion

The birth of centrifugal glass wool felt combines the scientific wisdom of silicate chemistry and material molding technology. When choosing, you need to pay attention to the scientific nature of the ingredients, parameter matching, and brand reliability, so as to maximize the effectiveness of its "invisible thermal insulation clothing".

If you have high-quality glass wool felt purchase needs or want to learn more about the product, you are welcome to contact us IKING GROUP.