AVX Ltd. has installed a rotating tube furnace to process tantalum powders in a single, continuous operation from Carbolite Inc., Watertown, WI. Because of the highly volatile character of the material, Carbolite designed an indirect heating system that avoids the use of elements and thermocouples near the processing tube. The system involves heating air in a separate heater box and transferring it to the tube in a pair of insulated ducts. The processing tube is stainless steel, 2500 mm long x 156 mm diameter, and is rotated by a flame-proof electric motor. It incorporates a tumbler bar to aid the process.