Bogie maintenance comprises the scheduled disassembly, inspection, repair, and reassembly of the complete bogie structure — frame, suspension elements, wheelsets, axleboxes, bearings, and brake equipment.
It is among the heaviest recurring tasks within maintenance and workshop equipment, and it runs to a fixed sequence.
Overhaul sequence
An overhaul begins with lifting the vehicle body to release the bogie. The bogie is transported to the workshop, cleaned, and stripped.
Frame inspection combines visual examination with magnetic particle or dye penetrant testing of welds and high-stress zones, and ultrasonic testing of the frame structure where internal defects are possible. Cracks exceeding permitted limits require repair welding qualified to DIN EN 15085, the standard governing welding of railway vehicles and components.
Suspension elements — primary and secondary springs, dampers, anti-roll bar assemblies — are inspected and replaced against defined criteria. Axlebox bearings are removed, the housings inspected, and new bearings fitted; wheelsets typically go separately for reprofiling or replacement.
After reassembly, the bogie passes through a bogie press or test stand simulating the vehicle’s static load. This settles the suspension, verifies ride height, and checks for geometry deviations before the bogie returns to service.
Lifting and handling equipment
Releasing the bogie starts with raising the vehicle body on synchronised electric jacks deployed along the underframe, coordinated by digital control to keep the lift level across all columns. Column types, capacities, and the safety standards governing them are treated as a subject in their own right elsewhere in this section.
Once the vehicle rests on its supporting columns, bogie drop tables — self-propelled, battery-powered platforms running on workshop tracks — collect the lowered bogie and move it to the maintenance area, keeping the lifting bays clear for the next vehicle.
Structural and fatigue requirements
EN 13749:2021 specifies the method for defining structural requirements of bogie frames, covering design procedures, fatigue assessment, and manufacturing quality. Structural calculations use its load cases to verify that repaired or modified frames remain within fatigue limits.
The standard forms part of a package with EN 12080 (axlebox bearings), EN 12081 (bearing grease), and EN 12082 (bearing performance testing).