High-Temperature Quartz Sight Glass for 800°C Furnace Applications
A high-temperature quartz sight glass is specifically designed for observing sand tumbling in a furnace at 800°C, where clear visibility, thermal stability, and resistance to combustion gases are critical.
PN 102294
Designed for 800°C Furnace Operation
The furnace operates at 800°C under static ambient pressure. Mechanical loading on the window is minimal, with a maximum dynamic pressure of approximately 1.7 atm, calculated from flue gas density and a given maximum gas velocity normal to the viewing surface. The combustion atmosphere consists primarily of water vapor (H₂O) and carbon dioxide (CO₂)
Why Fused Quartz for High-Temperature Sight Glasses?
- Fused quartz sight glass windows are widely used in high-temperature furnace applications due to their:
- Excellent thermal stability up to and beyond 800°C
- Low coefficient of thermal expansion
- Strong resistance to thermal shock
- High optical clarity for visible inspection
- Chemical resistance to water vapor and CO₂
These properties make quartz an optimal material for <strong>high-temperature furnace viewing windows</strong> where distortion-free observation is required.
Notice, the window is clamped into the flange with a threaded ring. The ring is secured from coming loose with pointed set screws. This design keeps the window always pressed into the housing regardless of thermal expansion.
Application: Monitoring Hot Particle Flow
The primary purpose of this furnace sight glass is visible inspection of hot sand particle flow. Operators can safely observe tumbling and movement in real time without interrupting furnace operation. This improves process validation, and operational awareness. The design is strictly for visual observation, with no requirement for significant pressure containment beyond ambient conditions.
Flush-Mounted Design Prevents Sand Accumulation
To maintain a clear line of sight, the quartz window is installed flush with the metal flange. This flush configuration prevents sand from collecting at the window interface - a common cause of view obstruction in particle-processing furnaces. By eliminating ledges or recesses, the design minimizes buildup and ensures long-term visibility in abrasive environments.
Protective Lid with Ceramic Gasket Seal
When inspection is not required, the entire high-temperature sight glass assembly is secured with an external metal lid. The lid seals using a flat ceramic gasket, reducing thermal exposure during non-operating periods.