Development of Ductile Iron Planetary Carrier Casting for High-power Nuclear Gearbox

Author of the article:CUI Yu 1 , LI Zengli 1,2 , ZHAO Jingxiang 1 , LI Kerui 1 , LI Ran 1

Author's Workplace：1. Zhengzhou Research Institute of Mechanical Engineering Co., Ltd., Zhengzhou 450001, China; 2. China Academy of Machinery Science and Technology Group Co., Ltd., Beijing 100044, China

Key Words： planetary carrier; ductile iron; casting process; melting treatment

Abstract：As an important structural part of the gearbox, the planet carrier bears a large load during the transmission process and requires high comprehensive performance. To further improve the strength and plasticity as well as the service life of the ductile iron planet carrier, according to the structural characteristics and performance requirements of the planet carrier of the high-power nuclear power gearbox, a reasonable control range of the casting composition was designed, and the casting process design and numerical simulation analysis were carried out. Finally, high strength and high plasticity planet carrier castings were manufactured by strictly controlling the molding, melting, spheroidizing treatment, inoculation, pouring and posttreatment processes. The microstructure and tensile properties of the attached cast test block were analysed. The results show that the matrix is mainly pearlite, and the nodularity reaches more than 90%. The tensile strength, yield strength and elongation are 797 MPa, 444 MPa and 7.0%, respectively, meeting the index requirements.