Draw furnace sealing assembly and method

An apparatus for cooperating with a downfeed handle to seal a top of an optical waveguide draw furnace, said apparatus comprising:

• an assembly constructed and arranged to removably cover the top of the draw furnace and mate with the downfeed handle, said assembly comprising an elongated sleeve having a base and defining a chamber for slidably receiving the downfeed handle therein;
• the top of the draw furnace being capable of being covered by said assembly;
• an inert gas supply communicating with said assembly to selectively deliver inert gas into the chamber;
• and
• a sealing mechanism supported by the elongated sleeve to mate with the downfeed handle, said sealing mechanism further comprises a circumferential gasket remote from the base, the gasket being positioned with respect to the sleeve such that the gasket conforms to the periphery of the downfeed handle, an oil lip sealing structure disposed to support the gasket, and a spring interposed between said sealing structure and the gasket to bias the gasket against the handle.