The main differences between glass fiber needle felt and high-silica needle felt are as follows:
### 1. **Raw Materials and Composition**
– **Glass Fiber Needle Felt**: Made primarily from ordinary glass fibers, which contain a higher amount of alkali metal oxides.
– **High-Silica Needle Felt**: Composed of high-silica glass fibers, with a silica (SiO₂) content typically above 96%.
### 2. **Temperature Resistance**
– **Glass Fiber Needle Felt**: The maximum operating temperature is generally around 650°C.
– **High-Silica Needle Felt**: Can be used continuously at temperatures above 900°C, with short-term resistance up to 1300°C.
### 3. **Structure and Performance**
– **Glass Fiber Needle Felt**:
– Offers good thermal insulation, sound absorption, electrical insulation, and corrosion resistance.
– Has a low thermal conductivity, with a value of approximately 0.035 W/m·K at room temperature.
– Provides good mechanical properties but is not suitable for long-term use in high-temperature environments with strong airflow or friction.
– **High-Silica Needle Felt**:
– Provides superior high-temperature resistance and low thermal conductivity.
– Maintains structural integrity even at high temperatures (above 800°C).
– Offers excellent sound insulation and high-temperature electrical insulation.
### 4. **Application Fields**
– **Glass Fiber Needle Felt**:
– Widely used in industrial filtration, thermal insulation, sound absorption, and insulation.
– Commonly applied in industries such as steel, chemical, automotive, and construction.
– **High-Silica Needle Felt**:
– Suitable for ultra-high-temperature environments, such as aerospace, automotive exhaust systems, and high-temperature protective covers.
– Also used in high-temperature filtration and insulation in metallurgy and chemical industries.
### 5. **Cost and Cost-effectiveness**
– **Glass Fiber Needle Felt**: Lower cost, making it suitable for ordinary high-temperature applications.
– **High-Silica Needle Felt**: More expensive due to the high cost of raw materials, but with superior performance.
### 6. **Other Characteristics**
– **Glass Fiber Needle Felt**: Low moisture absorption, lightweight, and flexible.
– **High-Silica Needle Felt**: Provides better high-temperature stability but has relatively weaker mechanical strength.
glass fiber needle felt is more suitable for ordinary high-temperature environments and cost-sensitive applications, while high-silica needle felt is ideal for ultra-high-temperature environments where superior temperature resistance is required.