The QDG 29 Dual Chamber Heat Treating furnace features a 2500°F (1370°C) high heat chamber for hardening and a 1875°F (1025°C) recirculating oven for preheating and tempering. The over/under configuration saves floor space. The hardening furnace is mounted on the bottom with the preheat/tempering furnace on top. The hardening furnace features silicon carbide elements and silicon carbide hearth plate. The preheat/tempering furnace features a powerful fan and recirculation muffle for high uniformity. This dual furnace is ideally suited for high speed tool steels. Typically high speed tool steels require preheating to about 1600°F (870°C), quick heating to about 2200°F (1200°C), and then various tempering cycles.