2022.11.02 Hyundai Rotem

How Are Trains Maintained

Hyundai Rotem
How are trains managed? They require a stricter management system than cars because it carries several people at once; in addition, we need to consider sustainability in the future.

What are the similarities and differences between cars and trains? Unlike cars that run on roads, trains run on railroad tracks. Plus, trains are huge enough to run with hundreds of people and loads. However, the two are basically similar vehicles in that they use a power source to spin the wheels. Trains, like cars, require regular inspection.

A railroad is a road for trains, and trains are basically a means of transportation similar to a car

In fact, trains require more maintenance than cars. This is because a lot of people and supplies need to be checked more closely at once. Especially for trains, punctuality is very important. This is because, for example, if a train cannot move due to a breakdown during operation, all trains using the same track may be delayed.

How does train maintenance work?

Railway vehicles such as trains and trains are stocked at the depot according to a fixed maintenance plan. The maintenance of railroad vehicles can be broadly divided into light maintenance and medium maintenance according to the implementation cycle and maintenance scope. Light maintenance refers to all kinds of inspections before and after the train operation. In Korea, it is conducted every 3 to 7 days to check whether the vehicle is abnormal or not and replace the necessary consumables.

Similar to automobiles, railroad cars require the replacement of air conditioner filters, air compressor filters, wipers, and other consumables such as various oils and lubricants at regular intervals. Railway vehicles use 20,000 to 30,000 parts, and each part has a lifespan and inspection cycle, which is managed through the MMIS (Maintenance Management Information System).

The maintenance of trains is in progress using IoT devices. MMIS helps trains to replace all parts on time and run safely
Trains made up of more than 20,000 to 30,000 parts run for 25 to 35 years through regular inspection and heavy maintenance

Heavy maintenance is similar to disassembling the entire car and then reassembling it. Trains generally go into heavy maintenance every 3 to 4 years, when they have driven about 400,000 to 500,000 km. During heavy maintenance, major systems and parts are separated and maintained. After precisely diagnosing the removed parts, the necessary parts are replaced. Since safety is of the utmost importance in trains, only trains that have completed a test drive and have proven both their performance and safety are allowed to operate.

Can train maintenance be sustainable?

Safety and punctuality are the most important factors in the railway industry

The trains have a lifespan of about 30 years, and mechanics maintain them until the end of their lifespan to ensure safety. The most used maintenance method today is preventive maintenance. Preventive maintenance is a method of replacing parts at regular intervals. By replacing parts in advance before they are damaged, it minimizes the possibility of failure, and it fits well with the characteristics of railway maintenance, where safety and punctuality are important.

But train maintenance must also be sustainable, which requires change. This is because the preventive maintenance method has a limitation of replacing parts that can still be used. What if you could check the condition and lifespan of their parts in real‒time so they can be used longer? If, for example, the life expectancy of a part could be increased by 70% to 90%, it would be possible to significantly reduce the resources required to produce new parts, as well as minimize the environmental pollution caused by discarding parts.

Safety is the most important aspect of train maintenance. But what about sustainability?

Evolution from preventive maintenance to condition‒based maintenance and predictive maintenance

Comparison of failure maintenance, preventive maintenance, condition‒based maintenance, and predictive maintenance

Hyundai Rotem is also proposing condition‒based maintenance and predictive maintenance to their railroad industry for sustainability reasons. Condition‒based maintenance starts with monitoring the health of systems and components. When the condition of a part deviates from the reference value, it is replaced. Of course, this is not a simple matter. This is because, in order to prevent the failure of various parts, multiple devices must be networked to collect field data in real time. High technology is required to build such a system, and the cost cannot be ignored. However, if the system is built, it is possible to accurately understand and use the life of the parts while minimizing the occurrence of failures ‒ and so will the KORAIL’s 448 new trains covered by Hyundai Rotem’s condition‒based maintenance system.

Monitoring the train in motion, in real‒time, can obtain various information as above

Condition‒based maintenance is also an essential step for predictive maintenance. Predictive maintenance is based on big data; The condition‒based maintenance system analyzes the data it collects and provides more information, such as the condition of the vehicle, the rate of wear of parts, and the probability of failure ‒ the more data, the more accurate. Also, since they are also affected by the environment, just like automobiles, the predictive maintenance system analyzes the environmental impact on trains more closely. For example, subways face high humidity and dust, and each line has different curves and slopes, so different parts of the body are subjected to different forces. Predictive maintenance offers solutions that cover even these areas.

Real‒time train diagnosis monitoring platform to be applied to Busan Urban Railway

Hyundai Rotem plans to utilize the condition monitoring system on Singapore’s ‘JRL (Jurong Region Line)’ and Taiwan’s ‘Green Line’. They are designing systems that use driving records and status information from key devices to diagnose the condition of trains and predict potential faults. This will greatly increase the availability and reliability of these trains.

Predicting the future for safety

Digital twin technology can quickly verify the possibility of tens of thousands of scenarios that can happen in the real world

Hyundai Rotem is testing the various futures of the railway industry ‒ just like the ‘Digital Twin’ technology that embodies reality in the virtual world. Digital twin technology can verify tens of thousands of scenarios that can occur in real life in a short period of time and can be widely applied in various fields. Hyundai Rotem is preparing a ‘hydrogen integrated control system’ that can monitor hydrogen electric trams as well as hydrogen production and charging facilities using digital twin technology.

Demo version of the hydrogen integrated control system presented at the 2021 Busan International Railway Technology Industry Exhibition

Here’s why Hyundai Rotem utilizes digital twin technology: Hydrogen is a clean energy that will become a new driving force in the future society. This is an early stage of preparing for the future, such as building infrastructure, so more thorough verification is needed. For example, hydrogen electric trams and hydrogen production facilities are complexly connected with so many different parts that it is very difficult for mechanics to find the part that is causing defects or abnormalities. By having digital twin technology in place, they can anticipate these situations and minimize the chance of defects as much as possible.

Digital twin technology will also contribute to the development of railway vehicles. The technology allows you to see the different interactions of a key component with other key components during its life cycle. In addition, various predictive scenarios can be created through real‒time diagnosis and analysis of parts. Hyundai Rotem plans to secure reliability and stability of the entire system by using digital twin technology to more effectively manage key devices of railway vehicles.

Digital twin technology is expected to play an important role in ensuring the reliability and safety of the entire system of railway vehicles

Hydrogen‒powered trains

A hydrogen electric tram under development by Hyundai Rotem

In the near future, the appearance of trains will also change. Hyundai Rotem is currently developing various ‘hydrogen trains’ such as hydrogen electric trams and hydrogen locomotives. The hydrogen train gets its power from the hydrogen fuel cell mounted on the vehicle. Compared to general trains that receive power from the outside, hydrogen trains do not require overhead catenary lines, substations, or power grids, so maintenance costs are lower.

The hydrogen electric tram being developed by Hyundai Rotem uses electricity generated from four 95kW fuel cells mounted on the Nexo

The hydrogen electric tram currently being developed by Hyundai Rotem is as long as three buses connected, and it uses electricity generated from four 95kW fuel cells mounted on the Nexo. The maximum speed is 70 km/h, and after it is shipped from the Changwon plant in the first half of 2023, it is scheduled to be operated on a track near Taehwagang Station in Ulsan in the second half of the year. And it will be fully commercialized after 2024.

The hydrogen engine is a technology to replace aging diesel locomotives. Hyundai Rotem has started joint development of a hydrogen locomotive with the Korea Railroad Research Institute and aims to commercialize it in 2030. The maximum speed of the hydrogen locomotive is 150 km/h.

A hydrogen locomotive can travel up to 1,000 km on a single charge

Trains will still play an important role in the future mobility society. This is why Hyundai Rotem is conducting various research. Even in the age of autonomous vehicles, trains capable of carrying large numbers of people and traveling long distances will still be valuable; Perhaps they will be able to transport many people to more diverse places faster than they are now. Today, Hyundai Rotem is doing its best for our safe movement and sustainable movement in the future.

HMG Journal Operation Team


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