The Grieve Corp.
The No. 885 inert-atmosphere tempering furnace is electrically heated to a maximum operating temperature of 1400¿F (760¿C) and has workspace dimensions of 24 in. wide x 36 in. deep x 24 in. high (610 x 915 x 610 mm). Total power of 42 kW is available in nickel-chrome wire coils, and a heat-resistant blower, powered by a 5-hp motor, provides vertical downward airflow to the workload. The 7 in. (178 mm) thick insulated walls comprise 1 in. (25 mm) thick 2300¿F (1260¿C) ceramic fiber blanket, 2 in. (50 mm) thick 1700¿F (930¿C) ceramic fiber blanket, 2 in. thick block insulation and 2 in. thick rockwool insulation.