CAF MIIRA has unveiled an innovative patented solution: a Condition‑Based Maintenance (CBM) strategy for railway gearboxes that operates without any onboard sensors. This new approach offers railway operators a pragmatic, efficient and immediately deployable method for optimising gearbox maintenance activities.
Addressing the challenges of traditional CBM
CBM has gained relevance in the railway sector as an approach positioned between preventive and corrective maintenance, allowing interventions to be better aligned with real operating conditions. However, traditional CBM implementations often rely on onboard sensors, vibration‑based diagnostics or real‑time oil‑quality monitoring systems. These technologies introduce added complexity, cost, and integration challenges.
In many cases, such systems require dedicated hardware, modifications to gearbox housings, periodic oil sampling or long learning periods before diagnostics become reliable. As a result, the return on investment can be uncertain for operators.
MIIRA’s pragmatic approach: CBM without onboard hardware
MIIRA has developed a CBM strategy that eliminates the need for embedded sensing equipment, providing operators with a cost‑effective and operationally simple alternative. The approach is based on three pillars:
- Engineering expertise in gearbox design and behaviour
- Real operational data, available through the vehicle traction system via CAF’s Leadmind platform or from a data pool
- Validated fatigue‑life and ageing models, extensively used across the industry for rotating components
By combining these elements, MIIRA can analyse real gearbox usage patterns and adjust maintenance intervals based on actual component loads and operating conditions — without adding new hardware or interfaces.
Overhaul extension using real‑world data
The gearbox Overhaul is typically the most expensive maintenance activity in the gearbox lifecycle, often representing 70–75% of the total gearbox maintenance cost.
Using traction‑system data available through Leadmind or from a data pool, MIIRA recalculates the actual remaining life of gearbox bearings, allowing Overhaul intervals to be adapted to real usage conditions:
- Extended when the load profile is lower than originally assumed
- Shortened when operating conditions are more demanding, ensuring safety and reliability
This data‑driven and hardware‑free method allows operators to optimise maintenance plans and potentially avoid unnecessary Overhauls in specific projects, depending on operational patterns and application needs.
A solution aligned with efficiency and sustainability
MIIRA’s new CBM strategy reinforces the company’s commitment to combining technical excellence, operational pragmatism and sustainability. The approach delivers:
- Lower lifecycle maintenance costs
- Higher fleet availability
- Reduced material consumption
- Reduced risk of downtime caused by in‑service failures
- Simplified integration with existing integral maintenance platforms
Leveraging decades of gearbox‑engineering experience and operational data from CAF fleets, MIIRA continues to strengthen its position as a leader in integrated wheelset and gearbox solutions.
