Hokkaido Railway Company selected NSK bearings for the H5 rolling stock to be employed on the Hokkaido Shinkansen high speed rail project, between Shin-Aomori and Sapporo. The initial section is due to open in March 2016, and safety and high reliability have been essential parameters in the selection, due to ultra-high speed involved up to 320 kph.
NSK’s oil bath, double-row cylindrical roller bearings have been chosen for use on the axles, in order to facilitate high-speed rotation without generating much heat, while ceramic-coated insulated bearings have been adopted for the main traction motors, for their proven safety record and lightness, helping prevent electrical pitting on the rolling surface. In addition, for the drive units, subjected to considerable vibration, the NSK bearings chosen feature high strength cages that have been subjected to nitriding treatment, to enhance shock resistance. NSK is the sole bearing manufacturer supplying bearings to all variants of Japan’s Shinkansen rolling stock since the initial ‘0 Series’, launched in 1964, another reason that persuaded Hokkaido to choose NSK as supplier, also due to the high reliability recorded in the severe cold and snow conditions of japanese winters.