Landon Kingsway Furnace Inspection Windows can be used on boilers, air heaters, or furnaces which require an observation window and a test point with a small opening for access of a flame mirror. Comes supplied in two parts, with or without backing plate.
The window itself is ¼” diameter armour plate heat resistant glass ¼” thick, as a replaceable item. The complete assembly consisting of inspection window with a backing plate may be bolted or screwed to the furnace front plate with ¼” dia. bolts or screws. The backing plate is constructed of mild steel to EN1A 3/16” thick and has four clearance holes 9/32” dia for fitting to the relevant furnace front plate.
The main inspection window body is constructed in cast iron and is secured to the backing plate by means of a 2BA cheese head screw ½” long, the main hinge block being welded to the backing plate in such a position to accommodate correct alignment for the clearance hole in the backing plate and the whole window assembly being fitted to the hinge, then secured in position by a 2BA hexagon bolt and nut. The sight glass assembly is sealed to the backing plate by means of a gasket.
Further sealing is accommodated by gasket rings each side of the glass, the glass being finally held, clamped in position by the brass cover plate, thus preventing any possibility of rattling and extraneous air entry.
In order to protect the glass from sooting up and continual subjection to heat, the inspection window is fitted with a glass guard plate, made from mild steel to EN1A, 1/8” thick. The complete assembly being hinged in the main casting of the inspection window with a spring loaded handle which keeps the guard normally closed until required for use.