Residual stresses

Implementation of a new device

Tests objectives :

Evaluate residual stresses in railway components through three types of measurement:
• ultrasonic
• extensometry
• X-ray diffraction

Tests facilities :

• Ultrasonic measurements: device for measuring on a test bench or under the vehicle (with or without contact)
•  Extensometry: strain gauges used to measure stress after successive cuttings of the part (destructive method)
• X-ray diffraction measurements: portable system (iXRD MGR40) for on-site measurements – non-destructive method for surface evaluation + semi-destructive method for sub-layer evaluation

Testing norms :

EN 13261-Railway applications – Wheelsets and bogies – Axles – Product requirements Measurements on axles using X-Ray diffraction

EN 13262- Wheelsets and bogies- Wheels – Product requirements. Extensometric measurements

EN 13979-1+A2- Wheelsets and bogies – Monobloc wheels – Technical approval procedure – Part 1: Forged and rolled wheels. Utrasonic measurements

UIC 510-5 OR- Technical approval of monobloc wheels – Application document for standard EN 13979-1

Quantifying the residual stresses of a component on the client’s premises using a portable diffraction system to prevent the occurrence of failures.

Tests objectives :

Assess residual stresses for both new and used parts:

• Validate repair methods based on welding
• Qualify products
• Characterize finishing treatment, stress relieving treatment, etc.
• Monitor constraints in revenue service
• Quantify residual austenite formed during poorly controlled heat treatments that can cause component breakages (bearings, springs)

Tests facilities :

• X-RAYBOT: Portable system used for in situ measurements

Testing norms :

EN 15305 – Non-destructive testing – Test method for residual stress analysis by X-ray diffraction