Grieve’s No. 863 is an electrically heated 1,400°F box furnace used for preheating molds. It has 52 kW installed in nickel chrome wire coils supported by a stainless steel frame. A heat-resisting alloy recirculating blower is powered by a 7½-hp motor with a V-belt drive and provides upward airflow to the oven. Workspace dimensions measure 30" × 48" × 30".
The unit has 7"-thick insulated walls with stainless steel covers. It is built with inert atmosphere construction, which consists of a continuously welded outer shell, high-temperature door gasket, sealed heater terminal boxes, inert atmosphere inlet and inert atmosphere outlet.
Controls on the furnace include a motor-operated vertical lift door and a four-point strip chart recorder.