Description
Frederickseal Mica Shields for flat gauge glass are thin, transparent protective layers of natural mica installed on the process side of a flat gauge glass (especially in boiler water level gauges). Its purpose is to protect the glass from chemical and mechanical damage, greatly extending service life in harsh conditions.
Simply put, the mica shield (mica sheet) is a clear, heat-resistant plate made from muscovite mica, chosen for its ability to withstand:
- High temperatures
- Steam and water impurities
- Chemical attack
- Erosion from flashing water or high-velocity steam
It is cut to the same shape as the gauge glass and placed between the gauge body and the glass.
Mica Shields are used to prevent or reduce:
- Caustic cracking from alkaline boiler water
- Etching or erosion at high temperature and pressure
- Corrosion from dissolved salts
- Mechanical abrasion from turbulent fluids
A mica shield absorbs this damage, preventing the glass from failing prematurely.
- Chemical Protection
Stops alkalis, acids, and boiler water impurities from attacking the glass surface.
- Thermal Protection
Withstands temperatures up to 1100°F, preventing thermal shock to the glass.
- Mechanical Protection
Resists erosion caused by:
- High-speed water jets
- Steam flashing
- Fine particulate matter
