The difference between high-temperature resistant glass wool and ordinary glass wool

Glass wool, a commonly used thermal insulation material, plays a crucial role in many fields such as construction and industry. It is a man-made inorganic fiber made by fiberizing molten glass to form a cotton-like insulating material. With its many advantages, including good formability, low bulk density, low thermal conductivity, excellent thermal insulation, good sound absorption, corrosion resistance, and stable chemical properties, glass wool is widely used in various applications.

In the construction industry, glass wool is used in a wide range of applications, from exterior walls and partition walls to ceilings, interior walls, suspended ceilings, and even for water pipe insulation, soundproofing, and vibration damping. For example, in exterior wall insulation systems, it effectively reduces heat transfer, helping buildings maintain a comfortable indoor temperature while reducing energy consumption. In interior partition wall applications, it not only absorbs environmental sound but also has good fire resistance, allowing for more efficient sound insulation and noise reduction by replacing traditional bricks with thinner walls.

In the industrial sector, glass wool is equally indispensable. It demonstrates excellent applicability to a wide range of complex industrial insulation needs. In industries such as power generation, metallurgy, petroleum refining, and chemicals, glass wool excels in providing insulation, heat insulation, and noise reduction for equipment such as boilers, flues, hot air ducts, dust collectors, and reactors, offering strong support for the safe and stable operation of enterprises.

In addition, glass wool plays an important role in energy saving, heat insulation, sound absorption, and sound insulation in fields such as HVAC, steel structures, acoustics, and automotive insulation, and has become a powerful "helper" in the development of many industries. Today, we will focus on discussing high-temperature resistant glass wool and ordinary glass wool, and see what the differences are between them.

II. Comparison of Raw Materials and Production Processes

(a) Raw materials

The main raw material of ordinary glass wool is usually glass, such as quartz sand, feldspar, dolomite, limestone, etc., which are melted together with some chemical raw materials such as soda ash and borax to form glass. These raw materials are melted in a high-temperature furnace at a high temperature of 1400℃ to 1600℃ to form molten glass, which is then processed into glass wool through related processes. Its composition contains about 50% to 70% silicon dioxide (SiO₂), which can give it good thermal stability and chemical corrosion resistance; 10% to 30% aluminum oxide (Al₂O₃), which helps to improve heat resistance and maintain its thermal insulation performance under certain high-temperature environments; and about 5% to 15% calcium oxide (CaO), which can improve processing performance and increase material strength. It also contains other elements such as sodium oxide (Na₂O) and magnesium oxide (MgO), which can be adjusted as needed.

High-temperature resistant glass wool is made by adding special high-temperature resistant materials to ordinary glass wool raw materials to enhance its high-temperature resistance. For example, some high-temperature resistant glass wool products add flame retardants (such as polysiloxane flame retardants and silicone resin flame retardants) and flame retardant synergists (such as synergist FR-18), making the product's flame retardant performance better and effectively preventing the spread of fire in high-temperature environments. At the same time, preform reinforcing powder (prepared from silicon carbide and bentonite in a certain proportion) is added, which can improve the flexural strength of the glass wool product and prevent the strength from decreasing due to external factors. In addition, the addition of anti-aging additives (made from nano zinc oxide and polyester-type ultraviolet absorbers in a certain proportion) can enhance its anti-aging effect, so that it can maintain good performance and extend its service life even under long-term use and exposure to ultraviolet radiation. The addition of these special raw materials allows high-temperature resistant glass wool to adapt to higher temperature environments, such as meeting the thermal resistance standard (high temperature resistance > 350℃), while the performance of ordinary glass wool may be greatly reduced in such high-temperature environments, failing to guarantee good thermal insulation and other functions.

(ii) Production process

The production process of ordinary glass wool is relatively simple and energy-efficient. First, raw materials are prepared. After selecting various main raw materials such as quartz sand, they are mixed in proportion and melted in a high-temperature furnace to form molten glass. Then, the molten glass is drawn into fine filaments, or glass fibers, using wind or centrifugal force. Centrifugal methods are commonly used, such as centrifugal blowing through a glass wool centrifuge to obtain glass fibers. These fibers are then stacked to form glass wool felt or boards. Phenolic resin is added as an adhesive, and finally, the fibers are placed in an oven to cure and solidify. The entire process is relatively less demanding in terms of temperature and time control, and the equipment and processes are less complex, resulting in lower energy consumption. This gives ordinary glass wool a cost advantage, allowing it to be widely used in various insulation and soundproofing applications where temperature requirements are not particularly high.

The production process of high-temperature resistant glass wool is much more complex and energy-intensive. Taking a high-temperature resistant glass wool product as an example, firstly, numerous raw materials, such as glass fiber, adhesives (e.g., boron-modified phenolic resin), flame retardants, flame retardant synergists, and water, must be prepared according to precise weight ratios. A portion of the raw materials is first poured into a mixer and thoroughly mixed. After mixing, the remaining raw materials are added and mixed again until homogeneous. Next, after the raw materials are homogeneous, the mixture is naturally heated to 45℃～50℃, then cooled to 10℃～12℃ to ensure complete reaction. After standing for 3～4 hours, a liquid intermediate material is obtained. This intermediate material is then transported to a fiber forming machine, where fiber production begins at a flow temperature of 400±50℃. The fibers are then evenly sprayed after calculations to interweave and form white wool. Finally, the formed white wool is passed through a hot air blower at a temperature of 190℃～230℃, which penetrates and heats it evenly from top to bottom at a frequency of 8～20Hz. After curing, it is cooled and cut to obtain the finished product. This process requires strict control over temperature, time, raw material ratio, and operation sequence at each stage. Even slight deviations can affect the high-temperature resistance and other properties of the final product. Moreover, the complex process and high temperature requirements result in high energy consumption and increased costs. However, it is precisely because of these factors that high-temperature resistant glass wool possesses excellent properties such as high-temperature resistance, flame retardancy, aging resistance, and bending resistance, meeting the stringent requirements of high-temperature industrial fields such as power, metallurgy, and petroleum refining.

III. Performance Characteristics Comparison

(a) Temperature resistance

Ordinary glass wool typically has a temperature resistance of around 250℃. For example, in common building exterior wall insulation scenarios, when the ambient temperature remains below 200℃ for extended periods, it can maintain its insulation, heat insulation, and structural stability well, ensuring a relatively constant internal temperature and fulfilling its normal insulation function. However, once the ambient temperature approaches or exceeds its temperature resistance limit, such as near high-temperature industrial pipelines where temperatures reach above 300℃, ordinary glass wool may experience fiber softening and a decrease in structural strength, leading to a significant reduction in insulation effectiveness or even damage, rendering it unusable.

High-temperature resistant glass wool typically has a temperature resistance of 500℃ or even higher. In the power industry, the temperature around some power generation equipment is often at a high level. High-temperature resistant glass wool can maintain a good fiber state in a high-temperature environment of around 500℃, effectively preventing heat transfer, maintaining stable thermal insulation performance, providing reliable thermal protection for equipment, ensuring the normal operation of equipment, reducing energy loss caused by heat dissipation, and better adapting to harsh operating conditions such as high-temperature industrial environments.

(ii) Chemical stability

Ordinary glass wool generally has low chemical stability and is relatively susceptible to corrosion from acids and alkalis. In places with volatile chemicals or significant acidic/alkaline environments, such as certain areas of chemical workshops, if ordinary glass wool is used as insulation material, prolonged contact with these chemicals may damage its internal fiber structure, leading to corrosion and deterioration. This causes the glass wool to gradually lose its original insulation, heat insulation, and sound absorption properties, affecting its service life and potentially creating safety hazards due to structural damage, requiring more frequent replacement and maintenance.

High-temperature resistant glass wool is better able to resist chemical corrosion in high-temperature environments, thanks to its special raw materials and production process. In the same high-temperature chemical environment, high-temperature resistant glass wool, with its excellent chemical stability, can maintain a relatively intact fiber structure and continue to perform its excellent thermal insulation function. Its performance is not easily degraded by chemical substances, thus ensuring long-term stable use in corresponding application scenarios. This reduces problems such as unstable equipment operation and energy waste caused by material damage, providing reliable protection for industrial production and other applications.

(iii) Tensile strength

The fibers of ordinary glass wool are relatively loosely bonded, resulting in relatively weak tensile strength when subjected to external forces. For example, during installation, if the construction workers apply improper force, or if it encounters slight external forces such as pulling or vibration during subsequent use, the fibers of ordinary glass wool are prone to breakage and separation, leading to localized structural deformation. This affects its overall thermal insulation and heat insulation performance, and in severe cases, it may even cause sagging and scattering, affecting its aesthetics and normal function.

High-temperature resistant glass wool differs in that its fibers are more flexible and tightly bonded together. When subjected to external tensile forces, its strong tensile strength allows it to better maintain structural integrity. In industrial environments where frequent equipment maintenance and personnel movement may cause external disturbances, high-temperature resistant glass wool, once installed, can maintain its condition even under tension and vibration, preventing fiber breakage and structural damage. This ensures the continued effectiveness of its thermal insulation function and reduces the cost and workload of repair and replacement due to material damage.

(iv) Fire resistance

Ordinary glass wool is a Class A non-combustible material with excellent fire resistance. In emergencies such as building fires, ordinary glass wool can effectively prevent the spread of fire, buying time for evacuation and fire rescue, and protecting lives and property. For example, in the wall and ceiling insulation and soundproofing applications of ordinary residential buildings and office buildings, ordinary glass wool will not burn if a source of fire is present, thus slowing down the spread of fire to a certain extent.

High-temperature resistant glass wool also boasts excellent fire resistance. It not only does not burn in high-temperature environments but also maintains its structural stability and thermal insulation functions. In industrial fields with extremely high temperatures and fire safety requirements, such as petroleum refining and metallurgy, high-temperature resistant glass wool, even under the threat of high-temperature flames, can still prevent fires from causing greater damage to equipment and pipelines, ensuring the safe operation of industrial production. Together with ordinary glass wool, it contributes significantly to fire safety in various application scenarios.

(v) Hydrophobicity

Ordinary glass wool has a certain degree of water repellency, which allows it to avoid problems such as a sharp decline in thermal insulation performance due to excessive moisture absorption after becoming damp. For example, in some ordinary indoor pipe insulation scenarios, where there is occasional contact with small amounts of moisture, ordinary glass wool can rely on its water repellency to maintain basic thermal insulation functions, ensuring a relatively stable temperature of the medium inside the pipe and reducing heat loss.

However, high-temperature resistant glass wool has higher hydrophobicity, which better resists moisture intrusion. In outdoor industrial insulation scenarios with high humidity or potential rain, high-temperature resistant glass wool can quickly expel moisture or prevent it from penetrating the internal fiber structure, even if its surface comes into contact with a lot of water. This better maintains its thermal insulation performance and extends its service life. In contrast, ordinary glass wool's thermal insulation performance and structural stability are more affected when exposed to high humidity or frequent water contact for extended periods, while high-temperature resistant glass wool can function more stably thanks to its high hydrophobicity.

(vi) Environmental protection and health

Both ordinary glass wool and high-temperature resistant glass wool are non-toxic and harmless to the human body. The raw materials and adhesives used in the production of ordinary glass wool undergo strict processing and will not release harmful substances such as formaldehyde and benzene. When used in construction, industry, and other fields, it will not pose a threat to the health of operators and people in the surrounding environment, and meets environmental and health requirements.

The same applies to high-temperature resistant glass wool. Although its production process is more complex and involves the addition of various special components such as flame retardants and preform reinforcement powder, these components, under reasonable proportions and process control, will not produce substances harmful to human health. Furthermore, during use, whether in high-temperature industrial environments or other application scenarios, it can ensure environmental safety, meet people's expectations for environmental protection and health, and allow users to confidently apply it to various insulation and heat insulation projects.

IV. Comparison of Application Areas

(I) Application areas of ordinary glass wool

Ordinary glass wool, with its excellent thermal insulation and sound absorption properties, is suitable for many applications in general temperature environments. It has a wide range of applications in the construction industry. For example, in the exterior wall insulation of various buildings such as residences, office buildings, and shopping malls, ordinary glass wool effectively reduces the transfer of heat between indoors and outdoors. In winter, it prevents heat loss from the interior, keeping the interior warm and comfortable; in summer, it blocks high temperatures from entering the interior, maintaining a cool indoor environment, while also reducing the energy consumption of air conditioning and other cooling and heating equipment. In interior walls, it can play a role in sound insulation and noise reduction, reducing the transmission of sound between rooms and improving the quietness of living or working environments. In ceilings and suspended ceilings, ordinary glass wool helps control indoor temperature and absorbs sound from above, effectively improving the acoustic environment in places such as large shopping malls and exhibition halls. For water pipes in buildings, ordinary glass wool can wrap the outside of the pipes to prevent the hot water inside from losing heat too quickly and to prevent the pipes from freezing and bursting in winter.

Ordinary glass wool also has important applications on ships. For example, in the bulkheads and pipes inside the cabin, using ordinary glass wool for thermal insulation can improve the comfort inside the ship, making the temperature of the environment where the crew and passengers are located more comfortable. It can also reduce the transmission of noise generated by ship engines and other equipment, creating a relatively quiet space.

In air conditioning systems, ordinary glass wool is often used as insulation material for components such as air ducts. It can ensure that the temperature of the cold or hot air delivered by the air conditioner is relatively stable inside the duct, reduce heat loss, improve the operating efficiency of the air conditioner, and help reduce operating energy consumption. It is widely used in various commercial places, industrial plants, and residential buildings equipped with air conditioning systems.

In summary, ordinary glass wool fully leverages its advantages in thermal insulation, sound absorption, and noise reduction in these typical temperature environments, ensuring the smooth operation of related fields and the comfortable lives of people.

(II) Application areas of high temperature resistant glass wool

High-temperature resistant glass wool plays an irreplaceable role in many fields where high-temperature environments are predominantly present due to its excellent high-temperature resistance. In the steel industry, for example, as the outer insulation layer of high-temperature equipment such as steelmaking furnaces and blast furnaces, high-temperature resistant glass wool can withstand extremely high temperatures, effectively preventing heat loss and reducing heat dissipation. This not only reduces energy consumption but also helps maintain a suitable operating temperature environment around the equipment, ensuring the safety of operators and protecting other surrounding equipment from the effects of high temperatures.

In the petroleum industry, places such as oil refining units and oil pipelines are often in high-temperature environments and have strict requirements for fire prevention and heat insulation. High-temperature resistant glass wool is wrapped around these areas so that even in high ambient temperatures, it can maintain its stable performance and continue to play its role in heat insulation, preventing heat loss that could cause changes in oil temperature and affect quality. At the same time, it avoids potential safety hazards caused by high temperatures, such as fires caused by high temperatures igniting nearby flammable materials.

In the chemical industry, various chemical reaction vessels, high-temperature steam pipelines, etc., usually need to operate under specific high-temperature conditions. The application of high-temperature resistant glass wool can ensure the heat stability of these devices and pipelines, avoid excessive heat loss affecting the chemical reaction and material transportation, and its good chemical stability can also resist the corrosion of corrosive substances that may exist in the chemical environment, ensuring long-term stable use, which meets the stringent requirements of chemical production for high temperature, safety, stability and other aspects.

Therefore, high-temperature resistant glass wool, with its advantages of high temperature resistance, thermal insulation and chemical stability, has become one of the key materials for ensuring safe and efficient production in high-temperature industrial fields such as steel, petroleum and chemical industries.

V. Cost-effectiveness considerations

When considering the cost-effectiveness of high-temperature resistant glass wool versus ordinary glass wool, it is necessary to take into account multiple factors and make a trade-off based on actual needs.

In terms of price, ordinary glass wool is generally cheaper due to its readily available raw materials, relatively simple production process, and low energy consumption. The market price for ordinary quality glass wool is typically around 30-50 yuan per square meter, while even high-quality quality is usually under 100 yuan per square meter. In common applications such as exterior wall insulation and interior sound insulation, the extensive use of ordinary glass wool is more cost-effective, achieving basic functions like insulation, heat insulation, and sound absorption at a lower cost, meeting the requirements of general environments.

High-temperature resistant glass wool, due to the addition of special high-temperature resistant materials, has a complex production process and high energy consumption, resulting in higher costs and prices compared to ordinary glass wool. For example, high-temperature glass wool boards have a density (bulk weight) of 48K-64K and a thickness of 30-50, with prices ranging from 7 to 17 yuan per square meter; high-temperature glass wool felt has a density of 32K-48K and a thickness of 50-100, with prices ranging from 7.8 to 13 yuan per square meter. Furthermore, its price is also affected by many factors such as brand, specifications, and shipping location.

However, price alone is not enough; the cost-effectiveness must also be considered in conjunction with the usage scenario and performance requirements. In ordinary construction fields, such as exterior wall insulation, interior wall sound insulation, ceiling insulation and sound absorption, and general indoor and outdoor pipe insulation in residential buildings, office buildings, and shopping malls, the ambient temperature is generally not too high. Ordinary glass wool, with its good basic performance, is perfectly adequate. In this case, choosing ordinary glass wool is a very cost-effective solution, and there is no need to spend more money to use high-temperature resistant glass wool.

However, in high-temperature industrial fields such as steel, petroleum, and chemical industries, for example, the insulation of high-temperature equipment and pipelines such as steelmaking furnaces, oil refining units, and chemical reactors, there are high requirements for the temperature resistance, chemical stability, and tensile strength of materials. Ordinary glass wool cannot guarantee good performance in such high-temperature environments and may even be damaged. High-temperature resistant glass wool, on the other hand, can play a stable role, ensuring production safety and normal equipment operation. Although its initial purchase cost is high, from the perspective of long-term use and ensuring production efficiency, the cost-effectiveness advantage of high-temperature resistant glass wool in these critical high-temperature scenarios becomes prominent.

In summary, when choosing between high-temperature resistant glass wool and ordinary glass wool, one should fully consider the specific application scenario, the expected material performance, and the budget, weigh the advantages and disadvantages of both, and make a choice that better meets actual needs and offers higher cost performance.

VI. Conclusion

High-temperature resistant glass wool and ordinary glass wool differ significantly in several aspects. In terms of raw materials, ordinary glass wool primarily uses common glass raw materials, while high-temperature resistant glass wool adds special high-temperature resistant materials such as flame retardants and preform reinforcing powders. Regarding production processes, ordinary glass wool is relatively simple and energy-efficient, while high-temperature resistant glass wool is complex and energy-intensive. In terms of performance characteristics, high-temperature resistant glass wool is often superior to ordinary glass wool in terms of temperature resistance, chemical stability, tensile strength, and hydrophobicity. However, both exhibit good fire resistance and are non-toxic and harmless to the human body, meeting environmental and health requirements. In terms of application areas, ordinary glass wool is suitable for construction, shipbuilding, and air conditioning systems in general temperature environments, while high-temperature resistant glass wool plays a crucial role in high-temperature industries such as steel, petroleum, and chemicals. In terms of cost-effectiveness, ordinary glass wool is affordable and suitable for general applications; although high-temperature resistant glass wool is more expensive, it ensures production safety and equipment operation in critical high-temperature scenarios, giving it a long-term cost-effectiveness advantage.

In summary, the choice should be based on a comprehensive consideration of factors such as the specific usage environment, the requirements for material performance, and the budget. If the ambient temperature is not high and the performance requirements are conventional, ordinary glass wool is a good choice; however, it is suitable for harsh conditions such as high temperatures and chemical corrosion.