Furnace Observation Glass

Our Furnace Observation glass is manufactured by Corning® and is a dark cobalt blue glass. Furnace Observation glass is a low expansion glass for added heat resistance in furnace site glass applications. The cobalt blue color is designed to view flame for accurate settings or readings and still protect the viewer from harmful IR and UV rays. We carry 12" square blanks that can be ground and polished to the desired size and thickness.

Glass Code: Corning		5331
Type		Borosilicate
Color		Cobalt Blue
Principal Use		Furnace Observation
Thermal Expansion Multiply by 10^-7cm/cm/°C	0 - 300°C.	50. 0
Thermal Stress Resistance °C.		16
Viscosity Data (Data is subject to normal manufacturing variations.)	Strain point °C.	474
	Annealing point °C.	515
	Softening point °C.	720
Density g/cm³		2. 28
	Dielectric constant	7. 2
	Loss factor %	6. 5
Refractive index		1. 490