NGC Gears, one of the world’s largest wind power gearbox manufacturers, has completed the installation of two additional EndoFlex generators from UPC-Marathon, a Nitrex company, at its new facility in Jinhu, China location. This acquisition brings the total of generator sets to five since 2022, collectively generating an impressive 800 m³/h (22,252 ft3/h) capacity of endothermic gas supplied to carburizing and hardening furnaces used for processing various gear components. The latest installations in February and March of 2024 support the heat-treating operations of the company’s wind energy gearbox production.
Gas carburizing has been around for a long time. One could argue that gas carburizing is the most common heat treating process. Heat treaters performing gas carburizing are often characterized by a dirty environment, hazy surroundings, and that “smell.” While the product quality may be acceptable, gas carburized parts do come with some challenges, like excessive intergranular oxidation (IGO) or intergranular attack (IGA), which is often ground off. Low-pressure carburizing (LPC) has proven to be a much cleaner and very capable alternative process. Most furnace companies have combined LPC with high pressure gas quenching, which moved carburizing from the dark back room to a relatively “clean room” environment. However, there is still a strong need for oil quenching, which is the common feature of the long used standard integral-quench (IQ) furnace.
The optimum carburized and hardened case depth for each gear failure mode is different and must be defined at different locations on the gear tooth. Current gear rating standards do not fully explain the different failure modes and do not clearly define the different locations that must be considered.