Recently, CRCHI (China Railway Construction Heavy Industry) achieved another breakthrough in the key technology of large-diameter main bearings with the successful development of a 7.6-meter main bearing at its Changsha Second Industrial Park. Prior to this achievement, CRCHI had already independently developed and mass-produced main bearings with diameters of 5 meters and below. Building upon this foundation, their research and development team has continually pushed the boundaries of large-diameter main bearing technology, resulting in the successful production of 6-meter and 7.6-meter main bearings.
This achievement addresses a significant gap in main bearings for tunnel boring machines (TBM), covering the spectrum from small to large diameters. These bearings are pivotal components within the cutterhead driving system of TBMs, playing a critical role in transmitting complex and harsh loads. A primary reason for the significance of this advancement is that large TBMs can only move forward and cannot reverse; hence, a failure in the main bearing could lead to substantial losses.
Ensuring high load-bearing capacity and reliability of main bearings requires specific characteristics of the bearing steel: high purity, homogeneity, strength, toughness and wear resistance. Moreover, precision in bearing assembly, machining and lubrication plays a crucial role in ensuring the safe and reliable operation of these machines. CRCHI’s breakthrough not only signifies technical advancement but also lays a solid foundation for the growth of the tunnelling equipment industry.
Ausinland is proudly the partner of CRCHI in Australia and New Zealand.
