Heat treat furnace with multi-bar high convective gas quench

摘要

An improved cooling arrangement is disclosed for an industrial heat treat furnace. The furnace includes a closed end cylindrical heat treat chamber in which a plenum plate is suspended adjacent the rear end thereof. The plenum plate has a central underpressure opening and a fan between the rearward end of the furnace and the plate develops a wind mass which circulates into the furnace chamber and is drawn back into the fan through the plates central underpressure opening. Between the plenum plate and the furnace rearward end is positioned a first fixed fan diffuser followed by a second fixed fan diffuser. The first fan diffuser permits wind mass flow therethrough when the fan is rotated in a first direction but not in a second direction and similarly the second fan diffuser permits wind mass flow therethrough when the fan is rotated in a second direction but not in a first direction. A cooling coil arrangement is placed adjacent the second fixed fan diffuser to permit accurate control of the cooling of the work by simply cycling fan rotation direction from clockwise to counterclockwise.