Pushing the boundaries of express trains

The central Japan railway Company (JR Central) operates the Shinkansen superexpress bullet trains that connect Tokyo and Osaka – Japan’s two biggest cities.

Along with advanced technology and operation systems, safety has always been a top priority for JR Central. On the Tokaido Shinkansen line, the current 16-car N700A bullet trains (introduced in 2013) run at a maximum speed of 285 km/h, so the bolting system must be perfectly reliable. The NordLock Group has been providing wedgelocking washers since the first N700 model, which started commercial operations in 2007.

The washers helped solve a long-standing bolting issue that had previously taken many hours to secure and maintain, freeing up time for more detailed check-ups in the process. Using the washers, JR Central could also remove a significant number of locknuts, thus reducing the weight of the cars.

With commercial operations planned for 2020, the new N700S (S=Supreme) trains are currently being tested. The main feature of this new model is the improved underfloor equipment, which uses brand new technology to reduce the number of cars – from sixteen to twelve or even eight. This could make the N700S cost-effective for overseas markets, fitting well with the Japanese government’s infrastructure export policy.

JR Central is already developing the next big technological advancement in rail – the Superconducting Maglev magnetic levitation line. With an amazing maximum speed of 500 km/h, commercial operation is planned for 2027.

“At first, we weren’t keen on adopting new products”

Today, Central Japan Railway Company is very pleased with how the Nord-Lock wedge-locking washers are performing, but there was some initial doubt.

“To be honest, an extremely high reliability is required for this part and, at first, we weren’t keen on adopting new products,” says Tadashi Fujii, Manager, Shinkansen Operations Division Rolling Stock Department Rolling Stock Section. “We gradually placed our trust in the NordLock washers when seeing the actual performance on a vibration-testing machine, the comparison with the existing bolting parts referring to quantitative data, the technical support system, and so on.”

At the time, the pair of washers were not glued together like the current ones, but the Nord-Lock Group quickly responded to requests for improvements. “This was important, as we felt that we could always depend on the Nord-Lock Group’s support, whatever the circumstances,” Fujii says.

TIME-SAVER The washers helped solve a long-standing bolting issue that had previously taken many hours to secure and maintain.