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Whole Life Rail Axle Assessment and Improvement Using Ultrasonic Phased array and Corrosion Inspection Systems

Periodic Reporting for period 5 - RAAI (Whole Life Rail Axle Assessment and Improvement Using Ultrasonic Phased array and Corrosion Inspection Systems)

Reporting period: 2017-12-01 to 2018-05-31

The objective of the RAAI project was to develop novel NDT solutions for the corrosion assessment and crack detection as well as reliability software for high cycle variable amplitude corrosion fatigue of rail axles. Currently, the most sensitive non-destructive testing methods for inspection of rail axles are surface inspection methods designed for crack detection. Current trend is for axles to be withdrawn from service long before their design lives due to suspected corrosion developed on the surface.

RAAI has developed two novel methods:

1. Corrosion assessment,
2. Phased array ultrasonic.

The first method assesses the effect of corrosion on high-cycle fatigued components such as the axle and evaluates its remnant life thereby improving the sentencing of corroded axles. The second method is specific to hollow axles of high speed trains and aims to improve the speed of the inspection (by 75%) and improve crack detection reliability (almost 100% with a crack of 2-3 mm depth) without dismantling the wheel-set and with minimum time for inspection.

The RAAI project was initiated to fulfil the requirements of the rail industry for a non-destructive system for the inspection of rail axles which goes above the current state of the art. This is to facilitate reliable and fast inspection without the dismantling of the wheel set. The project results in the development, testing and validation of the RAAI inspection system.

The development and the realisation of optimised prototypes, their extensive test and validation in workshop conditions in different locations and the comparison with existing systems lift the technology readiness level (TRL) of the RAAI system to level 8. The RAAI system is now ready for commercialisation and will be offered to all potentially end-users by the project partners.
A complete overview and a detailed description of the available test axles and the axles which have to be procured for the project was produced. The preparation of new test axles by including cracks from fatigue tests was planned and the raw axles for these tests were provided.

Based on a review of the WOLAXIM project the specifications for the corrosion inspection system in the RAAI prototype were defined. Possible changes from the WOLAXIM project for further optimization of the construction, to achieve a higher scan speed along and around the axis, were investigated.

The project website was installed under www.raai-project.eu.

For the new system an automated data collection and image analysis probe with a related scanning system and a data acquisition and interpretation software was developed. The new system was designed and the manufacturing was completed.

The optimisation of the construction of the phased array probe, to achieve a higher sensitivity, was finished. The dependency of the incidence angle on the sensitivity especially in the transition regions was investigate theoretical by modelling and tested in laboratory trials. Therewith the angle was optimised for a better detecting of flaws in the curved surface with an acceptable signal-to-noise ratio at the plane surface of the axle.

Improved software modules which will provide the reliability of the axle under high cycle variable amplitude (HCVA) fatigue and corrosion conditions was developed for different materials. This includes the preparation and inputting of high cycle load spectra and the inclusion of the crack growth equations. The modules can be easily parametrised and applied by a new graphic user interface (GUI). It provides a simple evaluation of the calculated results for the predicted lifetime and the related inspection interval.

At the special meeting of ESIS TC24 in October 24th/25th 2016 in Leoben (Austria) the planned approach of the RAAI system and the first results of the project were presented to a technical audience. The posters were uploaded on www.raai-project.eu.

An ESIS TC24 workshop "Integrity of Railway Structures" was held in Wittenberge Germany, 25th and 26th of September 2017. Several presentations about the RAAI project were delivered. The presentations are available at: http://esistc24.mecc.polimi.it/wittenberge.html

The prototyping, demonstration and testing of the RAAI system were finished and the performance of the RAAI system has been verified.

The data research, for the evaluation of the cost of RAAI systems and its services for rail axle inspection was finished. The market research, for the determination of the overall market strategy, was done and the management structure was defined. The finance and revenue model and the promotion and distribution model were developed.

We presented the project results on the 10th Symposium for NDT in railroading on 13-15 March 2018 in Wittenberge (Germany). The presentations are available at: https://www.dgzfp.de/seminar/eisenbahn#vortraege

A further presentation is registered for the 45th Annual Review of Progress in Quantitative Nondestructive Evaluation on 16-19 July 2018 in Burlington (Vermont). See https://www.qndeprograms.org/home

The consortium members use the offered coaching service from EU experts regarding developing strategies for exploitation and market penetration. The first unit of the offered 12 day coaching is scheduled in June 2018 in Berlin.
The RAAI project will result in a group of novel devices and a software module for the inspection of rail axles. The project is closely related to Horizon 2020 dedicated SME Instrument topic “IT-1-2014: Small business innovation research for transport”. The SMEs in the consortium are all high technology SMEs who jointly form a supply chain with the following capabilities:

+ To engineer RAAI system so that it is (i) improved and reliable and (ii) economically viable for the rail operators;
+ To manufacture and market the system;
+ To provide on-site services with the system.

The RAAI system will have impacts on the European rail industries. Firstly, it will make inspection and assessment reliable and cost-effective and secondly it will improve the operation of the European rail industries. We will endeavour to enhance the two novel methods (phased array system for detecting cracks in hollow axles and corrosion inspection system for measuring corrosion assessment in rail axles) developed in the WOLAXIM project, to reduce the inspection cost and time, to increase the reliability of corrosion assessment thereby decreasing the sentencing of the axles, etc.

To ensure a maximum impact of the RAAI project, we will employ a multi-channel dissemination strategy to gain maximum visibility including academia, the industry, end-user organizations, policy makers, and the general public. The dissemination strategy will focus on:
+ Distributing relevant results among scientific communities;
+ Propagating research results in the form of new technologies, prototypes, and interactive concepts to the respective industry branches and public and corporate audiences;
+ Organizing seminars and workshops to disseminate knowledge on the methodology and technology used
+ Informing the general public of the project results by means of a website
Logo of the RAAI-project