4x5 (Product Code #45) Rectangular View Port

FOR LOW PRESSURE APPLICATION ONLY! (5 PSI or LESS)

Fruehauf Rectangular View Ports enable the operator to safely and clearly inspect the interior.
Adjustablee under actual operating conditions without combustion or air infiltration
Standard glass options include clear borosilicate (Pyrex) or clear quartz.
Custom lenses available upon request.
Includes a 1/4″ NPT purge hole for adding cooling capabilities with air or nitrogen
Can be replaced with a 1/2″ NPT hole
Sealant can be added to improve the seal in low-pressure applications
Mounting flange gasket is provided for installation between the unit and the furnace wall
Available as a standard, angular, or extra long model (see below for design information)

Standard Fruehauf 4x5 (Code #45)

Standard units available in Cast Iron , Carbon Steel, and Stainless Steel
Available with either clear borosilicate lens or clear quartz lens
E-dimension inside the fixture can be extended up to 20″
Custom Options.
- Machine modifications to suit specific requirements.
- Addition of high-temperature sealant to enhance pressure seal.
- Increase size of purge hole to allow more air flow.
- Adapt shutter with special pattern of holes to increase cooling.

30 deg angle on mounting plate
Available in Cast Iron and Stainless Steel
Available with either clear borosilicate lens or clear quartz lens
Custom Options.
- Machine modifications to suit specific requirements.
- Addition of high-temperature sealant to enhance pressure seal.
- Increase size of purge hole to allow more air flow.
- Adapt shutter with special pattern of holes to increase coolin