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Transcripción del abstract original del autor: For several years, the Carburizing and Carbonitriding operations carried out in a vacuum furnace have been done exclusively in electrical furnaces. To change this situation, Gaz de France joined a French industrial, leader on this market (ECM), in order to develop a heat-treatment vacuum furnace, heated with natural gas and able to carry out these operations. Carburizing needs high temperature, up to 950 °C, and to accelerate this treatment the pressure inside the cell has to be maintained between 5 and 10 absolute mbars. The project began at the end of 1997 and consisted of three phases (a feasibility study on a model, the study and the realization of a prototype, and an Industrial validation of the prototype named ICBP gaz) Several technical difficulties had been identified at the origin of the project and, at each phase, these difficulties were to be overcome to consider the following phase. The major difficulties were the perfect sealing of the heating equipment inside the heat-treatment cell, the accuracy of the temperature maintaining at 950 °C before treatment, the homogeneity of temperature along the external tube, and therefore the homogeneity of the temperature of the load before the carburizing operation. A version of a vacuum furnace heated by natural gas to carry out carburizing operations is now available. The official presentation of this new process took place officially in June 2002 at the congress of the ATTT (Technical Association of heat teatment) in Grenoble (France) and the first industrial reference is currently in hand.