Patent ID: 6257023
Filing Date: 2001-07-10
Classification: C03B,H05B

Abstract:
A fiber optic draw furnace (10) having a heating element (22) arranged inside a furnace shell (20) for drawing an optical fiber (F) from a preform (P), and having one or more fiber draw furnace insulation means (14, 16, 18) to separate the heating element (22) from the furnace shell (20) for reducing the thermal transfer therebetween;at least one of the fiber draw furnace insulation means (14, 16, 18) being made from rigidified high purity graphite felt consisting of a homogeneous mixture of graphite fibers and a graphite-based resin that is solidified for providing highly efficient thermal insulation between the heating element (22) and the outer furnace shell (20);the one or more insulation means (14, 16, 18) including either a bottom insulation ring (14), a cylindrical insulation insert (16) or a cylindrical insulation canister (18);the fiber optic draw furnace (10) including a bottom insulation plate (24) having a titanium coating; andthe bottom insulation ring (14) being arranged between the bottom insulation plate (24) and the outer furnace shell (20).