Railways are comprised of hundreds of thousands of individual components and moving parts, including complex mechanical and electrical systems that must work together seamlessly in order to ensure a safe and compliant operation. After all, safe and reliable service depends on equipment that’s in good working order, and equipment that’s well maintained and optimally functioning results in lower operating costs and less downtime due to unpredictable breakdowns and delays.
While rail operations fully understand the need for ongoing preventative maintenance, it’s a time-consuming and expensive process – and due to the challenges that exist in properly tracking and carrying out maintenance activities, it’s easy to allow these preventative measures to fall by the wayside. Here’s a look at a few of the most important best practices and considerations for train maintenance and efficient train maintenance scheduling:
- Dedicated Maintenance Facilities
- Cleaning Trains Not in Service and Wheel Lathes
- Rolling Stock Inspections
- Inspections and Maintenance Required by Law
Dedicated Maintenance Facilities
Trains require dedicated facilities for storage and maintenance. The basic form and function of maintenance facilities in the rail industry has remained largely unchanged over the past century, which can pose challenges for rail companies wanting to adopt more modern maintenance practices.
A maintenance facility, or depot, should consist of:
- Storage yard
- Areas for car cleaning
- Inspection shed or area
- Light maintenance shed or area
- Heavy maintenance shop
- Separate area or shop for locomotives
In some cases, inspection and light maintenance occur in the same building or area, and not all maintenance facilities will have separate shops or designated areas for locomotives.
A designated maintenance area should be easily accessible by both rail and road traffic, ideally with a configuration that enables trains to get into and out of the maintenance area without disrupting the flow of other rail traffic. There should be ample space for large trucks carrying heavy equipment to enter and exit the area as well. Vehicle delivery access by road may also be necessary.
Cleaning Trains Not in Service and Wheel Lathes
When a train is out of service (whether due to maintenance requirements, repairs, or simply not being in use), they must be stabled, during which time they should be cleaned and serviced. Regardless of the reason a train is out of service, taking advantage of stabling time to perform routine service and regular cleaning is a smart use of time.
Most modern train maintenance facilities have an on-site wheel lathe, or a wheel profiling facility. Like the tires on an ordinary, road-use vehicle, the tires on trains wear down over time and must be evaluated regularly to determine if they are in an acceptable condition. When the wheels are worn down beyond a certain point, there are two options: reprofiling the treads to the appropriate shape or replacing the wheels entirely. Reprofiling is a time-consuming and costly process, but fortunately, improvements in wheel design and maintenance now extend the period of time until reprofiling is necessary.
There are also guidelines to consider when it comes to reprofiling. Wheels on cars in the same bogie must have similar diameters up to a certain range (such as 5 mm), and wheels under the same coach may have slightly larger variants but are still subject to limitations (such as no more than 10 mm variation in diameter). Newer vehicles may require an even smaller tolerance, such as no more than 3 mm of variation in diameter. So, if a set of wheels requires reprofiling, not only must these wheels be addressed but other wheels in the same bogie and under the same coach to ensure that these guidelines are met. For this reason, proper planning can drastically reduce downtime and eliminate the excess costs of unnecessary reprofiling.
Rolling Stock Inspections
Rolling stock inspections are a crucial component of train maintenance, allowing for the detection of potential safety hazards and functional issues that can hinder performance and increase risks. Typically, rolling stock maintenance follows a schedule driven by one of several triggers:
- By mileage
- By time
- By condition monitoring
Time-based methods were traditionally used, with functions such as braking safety and wheel condition evaluated on a pre-determined schedule. Later, mileage-based methods became commonplace in an effort to perform maintenance based on the actual usage of the vehicle, rather than a specified amount of time during which a vehicle may have mostly sat idle (and therefore may have different types of wear on different components compared to a train that has spent much of that same time in active service).
Mileage-based maintenance also proved challenging, however, due to the sheer volume of documentation required to accurately track mileage across a multitude of individual vehicles, particularly without the aid of a comprehensive data collection and analysis solution.
Condition-based monitoring is the most modern method used to determine train maintenance schedules, relying on automated data collection and sensors to trigger maintenance checks and processes based on the real-world performance of the vehicle. These methods are also reliant on the use of a data collection and software solution, but as these systems are used more widely today, condition-based monitoring has become a practical and efficient means for managing and scheduling train maintenance activities. Of course, maintenance schedules must also be coordinated with utilization schedules to ensure efficient operations, making the use of comprehensive planning and scheduling software even more desirable for modern railway operators.
Inspections and Maintenance Required by Law
Because railways have been around for many years, they’re prevalent across the U.S. and in many areas of the world. Due to local climate and environmental conditions, it’s necessary for rail operations to adapt their maintenance processes and schedules to the local conditions. Likewise, state and local authorities typically set forth guidelines and regulations for the types of safety inspections and maintenance processes required for their local jurisdictions.
Broadly, the Federal Railroad Administration oversees these regulatory requirements in the U.S. It’s up to operators, however, to be familiar with regulations that impact any area in which a rail system operates and ensure compliance with all applicable local regulations.
Railway operations are complex by design, and it’s this nature that makes coordinating the planning and scheduling of train maintenance a challenging undertaking. From ensuring that proper maintenance facilities are available to coordinating maintenance with out-of-service times and accommodating transit demands, considering every facet of the overall operation is essential for optimal train maintenance practices.