High Temperature Glass View Port

The only transparent material that I know of that will maintain enough structural integrity at that temperature is Quartz. Problem is that it will cost a hell of a lot more than $150.

http://www.mcmaster.com/

Extreme-Temperature Quartz Pure Glass

• Color: Clear
• Max. Temp.: 2102° F, low end not rated
• Machine using diamond tools
• Annealed

Because it is 99.995% SiO₂ (silicon dioxide) many of the properties of this pure glass are superior to other glass. Its high purity provides excellent UV transmission, as well as high transmission in the visible and IR range. Uses include high-intensity lighting, fiber-optic production, and optical lens systems. Entire circles are ground and polished. Diameter tolerance is ±0.010"; thickness tolerance is +0.005". Discs 1/16" Thick 1/8" Thick 1/4" Thick Dia. Each Each Each 1" 1357T11 $7.26 1357T21 $10.12 1357T31 $13.10 2" 1357T12 15.55 1357T22 19.03 1357T32 26.39 3" 1357T13 25.70 1357T23 30.78 1357T33 46.49 4" 1357T14 56.25 1357T24 67.03 1357T34 82.93 5" 1357T15 77.76 1357T25 86.19 1357T35 108.00 6" 1357T16 127.44 1357T26 146.88 1357T36 178.62

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Try searching for Fused Silica. Quartz is the naturally occurring or laboratory grown crystal whilst fused silica is the commercially made equivalent & is generally much cheaper.

www.ljstar.com

Ask for Andrew Obertanic!

They just completed a job for me.

A very diverse firm with worldwide representation.

qaqcpipeman

Have you considered use of an air purge across the inside face of the glass?