L&L Special Furnace designed and built a heated-oil quench tank that will be used by a company for quenching various styles of heat-treated tools used in the forging industry. The tools are heat treated in a furnace to required hardness and then quenched in oil to set hardness. The quench tank holds 65 gallons of oil and is ideal for quenching parts 50-75 pounds. The quench-tank oil is agitated by an impeller with an explosion-proof motor and is heated with a 4.5-kW immersion heater to maintain the oil at a slightly elevated temperature to help eliminate oil flashing and fire potential. There is also a safety lid with fusible links that closes automatically if the fusible links melt, dropping the lid and blocking exposure of the surface of the oil to air to prevent a potential fire.

The quench tank has digital over-temperature protection. This shuts the heater off if the temperature is above a set level. The over-temperature protection will not allow the heater to operate until it has been manually reset and the oil temperature is below the programmed setpoint. The quench tank can be put on casters for portability.