High Temperature Quartz | Fused Silica for Extreme Thermal Applications
FGQuartz manufactures high-purity fused silica components designed for continuous high-temperature service. Our high temperature quartz products include furnace tubes, heating element supports, kiln furniture, observation windows and structural parts that withstand thermal cycling, rapid temperature changes and aggressive process atmospheres.
Why Fused Silica for High-Temperature Applications
Fused silica is one of the few materials that combines very low thermal expansion, high softening temperature, excellent thermal shock resistance and chemical inertness. These properties make it ideal for continuous operation at elevated temperatures where ordinary glasses and many ceramics fail.
FGQuartz high temperature quartz components are produced from high-purity fused silica and are widely used in industrial furnaces, heat-treatment systems, laboratory high-temperature equipment and process reactors that require long-term dimensional stability under thermal load.
Key High Temperature Quartz Products
Furnace Tubes & Process Tubes
Clear and opaque fused silica tubes for horizontal and vertical high-temperature furnaces. Designed for continuous service with excellent thermal shock resistance and dimensional stability.
Heating Element Supports & Insulators
Quartz rods, plates and custom-machined supports that hold heating elements while remaining electrically insulating and thermally stable at high temperatures.
Kiln Furniture & Structural Parts
Support plates, shelves, posts and custom fixtures used inside kilns and high-temperature chambers. Resistant to deformation and chemical attack under prolonged heat exposure.
Observation Windows & Viewports
High-temperature quartz windows that allow visual or optical monitoring of processes while maintaining hermetic sealing and thermal integrity.
Thermocouple Protection Tubes
Closed-end and open-end quartz tubes that protect thermocouples in high-temperature and corrosive environments while providing fast response and chemical inertness.
Custom High-Temperature Assemblies
Flame-worked and CNC-machined components fabricated to customer drawings for specialized furnaces, reactors and thermal processing equipment.
Typical High-Temperature Applications
- Industrial heat-treatment and annealing furnaces
- High-temperature process reactors and chemical vapour systems
- Laboratory tube furnaces and research high-temperature equipment
- Ceramic and glass manufacturing kilns
- Semiconductor and solar thermal processing equipment
- Vacuum and controlled-atmosphere furnaces
- Heating element assemblies and electrical insulation systems
Key Material Advantages
- Very low coefficient of thermal expansion for excellent thermal shock resistance
- High softening point suitable for continuous high-temperature service
- Outstanding chemical resistance to most process atmospheres
- Dimensional stability under prolonged thermal load
- Electrical insulation properties at elevated temperatures
- Available in clear and opaque grades depending on application needs
- Fully customizable geometries via CNC machining and flame forming
Manufacturing Capabilities for High-Temperature Parts
Precision Tube & Rod Production
High-quality fused silica tubes and rods drawn to controlled dimensions for furnace and support applications.
CNC Diamond Machining
Custom supports, plates, fixtures and complex geometries machined from solid fused silica stock with high dimensional accuracy.
Oxy-Hydrogen Flame Forming
Flanged tubes, closed-end protection tubes, multi-port assemblies and special shapes fabricated by skilled flame working and annealed for stress relief.
Frequently Asked Questions
Common questions about high temperature quartz glass components and their use in industrial and laboratory thermal systems.
Yes. FGQuartz accepts custom high-temperature quartz glass orders from a single piece, with no minimum order quantity. Drawings in DXF, STEP, IGES, or PDF format are accepted. The engineering team provides Design for Manufacture feedback within 24 hours of receiving a drawing, and a detailed quotation — including unit price, lead time, and volume pricing — follows within the same business day for standard-complexity components. Custom fabrication routes available include CNC diamond machining, oxy-hydrogen flame forming and welding, precision grinding for flat sealing faces, and quartz-to-metal assembly for vacuum flange and feed-through configurations.
High-temperature quartz glass is used across industrial heating systems including infrared curing ovens and radiant heaters; metal heat treatment furnaces for annealing, sintering, and brazing; chemical processing reactors for CVD coating, catalytic testing, and gas-phase reactions; the automotive industry for paint and powder-coat curing; food processing for infrared surface treatment and pasteurisation; pharmaceutical manufacturing for depyrogenation and dry heat sterilisation; laboratory and scientific research for tube furnace reaction vessels; plasma processing systems for ICP analytical instruments and industrial plasma treatment; and environmental monitoring for high-temperature gas sampling probes.
Yes. Hydrogen is one of the most common atmospheres used in quartz tube furnaces for bright annealing of metals, reduction of metal oxides, and sintering of powder metallurgy components. Quartz glass does not react with hydrogen at typical tube furnace operating temperatures. Standard safety practice requires purging the tube with inert gas before introducing hydrogen and after completing the hydrogen atmosphere step, to prevent explosive hydrogen-air mixtures from forming during heating or cooling transitions.
Clear fused silica transmits infrared radiation efficiently, making it the correct choice for infrared quartz heater tubes — where the heating element must radiate energy through the quartz wall — and for observation windows that require optical access to the process zone. Opaque quartz contains microscopic voids that scatter and absorb radiation rather than transmitting it, giving it low thermal emissivity and effective thermal insulation properties. Opaque quartz is used for furnace liners, thermal baffles, and insulating spacers where heat retention is required rather than transparency. Many industrial heating systems use both grades together in the same assembly.
FGQuartz supplies quartz furnace tubes for industrial tube furnaces in clear and opaque grades; infrared quartz heater tubes for short-wave and medium-wave IR heating systems; thermocouple protection tubes in single and double-bore configurations with flame-sealed closed ends; high-temperature observation windows and sight glasses in circular and rectangular formats; opaque quartz furnace liners for thermal insulation between the process tube and furnace heating elements; electrical insulators, electrode isolation sleeves, and high-voltage feed-through assemblies; combustion chamber liners; and fully custom high-temperature quartz glass assemblies produced to customer drawings.
High-temperature quartz glass combines properties that no single alternative material can match at elevated temperatures: continuous service capability well above the limits of borosilicate glass, near-zero thermal expansion that resists thermal shock during rapid cycling, chemical resistance to most industrial process gases and acids at high temperatures, and UV-to-infrared optical transparency that allows infrared heaters to radiate through their quartz enclosures to the workpiece. No other affordable material simultaneously provides all of these properties across the full range of industrial thermal processing temperatures.
Get High Temperature Quartz Components for Your Process
Tell us your maximum operating temperature, atmosphere, required dimensions and functional requirements. Our engineering team will recommend the appropriate grade and configuration and provide a detailed quotation — normally within 24 business hours.