Supporting Safety of Railways, All Day, Every Day, as They Continue to Become Faster and More Comfortable

The railways that support our daily lives, whether it's commuting to work or school or just traveling for leisure, have grown to become faster and more comfortable. Their low environmental impact also means that they are being increasingly considered as a preferred means of mobility for the future. But operating railways is not possible without a major focus on safety.

Hitachi High-Tech provides inspection and measurement technology capable of the early detection of risks that could lead to accidents, enabling quick and appropriate responses. All day, every day, it supports safe and reliable operations across Japan, including on the Shinkansen (bullet trains), JR conventional lines, private railways, and subways.

In recent years, new challenges have emerged such as skilled-labor shortages due to the declining birthrate, aging population, and retirement of veteran employees. Hitachi High-Tech technologies make full use of digital transformation (DX) to respond to these demands and contribute to sustainable railway business.

High-precision technologies support comfortable transport at 300 km/h

It has been 60 years since the Tokaido Shinkansen opened in 1964. Since then, it has expanded, with routes going from Hokkaido in the north to Kyushu in the south, and the number of trains has increased significantly. Some routes operate at speeds of more than 300 km/h.

There's a similar story for the conventional train lines. In the nearly 40 years since the transition of the Japanese National Railways (JNR) to the privatized JR companies, speeds have continued to increase, to a maximum operating speed of 160 km/h. In metropolitan areas, there is interoperability between multiple rail companies to provide transport for commuting to work and school.

Due to the evolution of vehicle technology, fast, comfortable, and quiet journeys are now the standard.

For safe and secure train journeys, it is essential to keep the rails and other infrastructure in good condition. The Hitachi Group has been developing inspection and measurement technologies since it began supplying railway track inspection vehicles to JNR in the 1960s.

Hiroaki Yamamura, Deputy General Manager's Representative, IS Sales Dept., IS Div., explains that

"Hitachi High-Tech provides solutions that ensure safety on a variety of routes, including Shinkansen lines and major conventional lines. In recent years, digital technologies and the Internet of Things (IoT) have been growing more advanced every year, enabling high-precision inspection."

Checking the condition of rails and overhead lines on regular trains

One of Hitachi High-Tech's strengths is track geometry inspection. Rails are always at risk of distortion and twisting. This is because the weight of trains running on top of them and changes in temperature cause loading in all directions. If distortion or twisting exceeds a certain level, it can lead to derailment.

Hitachi High-Tech railway track geometry inspection systems use laser and inertial technology to measure five different parameters: Longitudinal Level (vertical deviation), Alignment (lateral deviation), Gauge (minimum separation between rails), Cross-Level (height difference of the left and right rails), and Twist (change in Cross-Level over distance travelled). Track anomalies are detected in real time, enabling countermeasures to be enacted quickly and prevent accidents.

The trolley wires (overhead lines) are a piece of infrastructure just as important as the rails. There are two different types of power used for trains—electricity or internal combustion (mainly diesel)—but electricity is used for the Shinkansen and most of the major conventional lines in Japan. On electrified railways, electricity is supplied to vehicles from the overhead lines through a pantograph.

Overhead lines are gradually worn down by friction with the pantograph. The support structure is also delicately balanced and complex, for example stretching the contact wire in a zigzagging course, to evenly distribute pantograph wear. Hitachi High-Tech's overhead line inspection equipment checks the amount of wear based on the residual diameter of the overhead line and measures its lateral displacement and height.

IoT technology has enabled compact rail and overhead line inspection equipment to be installed under the floor or on the roof of revenue trains. Traditionally, a dedicated inspection vehicle was required, but this compactness made it possible to perform inspections during normal operation at the same time as carrying passengers.

Brian Rattray, Sales Engineering Manager, IS Sales Dept., IS Div., explains the benefits of installing inspection equipment into standard vehicles.

"It's a huge development to be able to see how train speed and weight affect rails and overhead lines through testing under actual operating conditions."

Utilizing data to improve the efficiency and sophistication of inspections

Hitachi High-Tech has also developed equipment for inspecting and measuring wayside equipment (support equipment for overhead lines), track components (such as bolts that secure rails to railroad ties), and peripheral equipment (tunnel inspection and obstacle detection around the track).

Fumihiko Kutsuki, General Manager, IS Sales Dept., IS Div., says that

"Rails and overhead lines can be inspected according to numerical values stipulated in laws and regulations, but there are many other elements that are difficult to quantify, such as rust or looseness, which depend on the experience of track maintenance staff. By introducing technologies such as 4K cameras, we can reduce the labor required and improve the efficiency of inspection and measurement."

The labor shortage caused by the declining birthrate and aging population in recent years has also affected railway operations. In particular, securing personnel to ensure safety after veteran employees have retired is a big challenge. Hitachi High-Tech's inspection and measurement technology, which could enable skills of veteran employees to be digitally inherited, is being seen as a potential solution to this challenge.

Kutsuki continues, saying

"Rather than just inspecting and measuring, we are also focusing on proposals where the data accumulated by the equipment can be analyzed for the early detection of problems and improvement of maintenance. Hitachi High-Tech has all the technologies required for observation, measurement and analysis, and we can leverage our ability to provide total solutions based on data utilization."

Hitachi High-Tech's latest technology has also changed the way inspection and measurement is utilized. Traditionally, the Time-Based Maintenance (TBM) method, which involves repairing and replacing parts at defined time periods regardless of the condition of the parts, has been the dominant method.

Now that data can be used, it is possible to detect signs of deterioration at an early stage, and to carry out maintenance only on problematic areas — known as Condition-Based Maintenance (CBM). This enables more efficient maintenance than ever before, while also reducing effort and costs.

There are many railway routes throughout Japan that are struggling to survive due to the decline in population and the progress of motorization. On the other hand, there is a movement to re-evaluate the benefits of railways as a preferred transportation system for the future with its low environmental impact. Inspection and measurement technology that can ensure safety with reduced effort and cost will contribute to the survival of those local routes.

Pursuing greater safety and contributing to the sustainable future of railways

Kutsuki looks ahead to the future, striving to provide solutions beyond the expectations of railway companies.

"Trains run as part of the landscape of everyday life, but behind the busy schedules is the diligent efforts of the railway companies. Awareness around safety is high and there are many things to learn. As partners in ensuring safety and reliability, we would like to continue to deepen our collaboration and co-creation with railway companies in the future."

As a comprehensive railway system integrator, the Hitachi Group covers all areas of railway operations, from the manufacture of rolling stock to the development of drive technology and the provision of security equipment and operational management systems. Hitachi are also actively involved in railway operations in Europe, Asia and various countries around the world.

Hitachi High-Tech will strive to strengthen its cooperation with other divisions to maximize the Group's comprehensive capabilities and aims to contribute to a sustainable future for railways by further improving its inspection and measurement technology.

Hitachi High-Tech Group has set five materialities (key topics) for solving social issues, based on its SDGs (sustainable development goals). The inspection and measurement technologies that support railway operation mainly contribute to "2) Contributing to healthy, safe, and secure lives," but also indirectly contribute to other materialities.