Advanced Asset Maintenance – Delivering the Promise

Kevin Fry

AEA Technology Rail, Derby, United Kingdom

Abstract

Over recent years there have been many technical developments in the field of rail vehicle condition monitoring and most key parameters can now be measured. Many applications of the technology however have failed to deliver their full business potential. The reasons vary but often relate to the difficulty of changing the maintenance processes involved or a lack of suitably skilled resource to manage effective implementation. In recognition of this, in recent years AEA Technology Rail has developed new technology designed to deliver much greater automation in the link between rail vehicle condition monitoring systems and the vehicle maintenance processes they feed. A new, open software system, called Xe@™ has been developed that takes the output of the various monitoring systems, applies technical and commercial business rules and can directly raise the required actions in the maintenance management system. By using a clear understanding of the business value of each aspect of monitoring, the new approach can be focused on automating the most valuable part of the processes first, driving through and securing the benefits of the monitoring technology. This paper describes the application of this Xe@™ technology for a UK train maintenance company where vehicles have wheels and brakes monitored with a number of different trackside systems, including some of the latest automated visual inspection systems. It describes how a new software system has been developed to take the output from the monitoring systems that previously required the day-to-day involvement of senior fleet technical and planning people. By using expert technical and commercial business rules it can automate the process of producing electronic work orders in the maintenance management system. The paper demonstrates how the new approach ensures a high standard of decision-making, frees the time of the most technically able staff to concentrate on other matters and helps ensure that the promise of the monitoring technology is really delivered to the business. The paper discusses what worked and what didn’t, and the lessons learnt. Finally, the paper describes how the priorities for implementation should be driven by a clear understanding of their value to the business.

Introduction

Over recent years there have been many technical developments in the field of rail vehicle condition monitoring and most key parameters can now be measured. The potential benefits of condition monitoring include the ability to provide frequent and accurate information that advises on action to be taken. This should provide the maintainer with the ability to plan maintenance activities more effectively, before problems actually manifest themselves. In short, the asset should be telling the maintainer before it develops a problem, avoiding delays and allowing the right action to minimize asset downtime. Discussion with most users of condition monitoring systems reveals that this ideal is far from being realized. Most users report being overloaded with data and having difficulty in finding the time of suitably skilled technical users to turn the measurement data into useful information with which to manage the business. There is clearly a gap between the potential that the technology offers and the delivery of benefits on the ground. In recognition of this, in recent years AEA Technology Rail has developed new technology designed to deliver much greater automation in the link between rail vehicle condition monitoring systems and the vehicle maintenance processes they feed.

The monitoring technology available New trains delivered in the UK are without doubt the most technologically advanced yet seen, providing many of the following features.

• Advanced train management systems; • Condition monitoring equipment for doors, engines, electric traction, even toilets; • OTMR; • Wheel slip and slide activity; • Passenger counting.

The on-train monitoring is supplemented by a range of trackside measurement systems, many supplied by AEA Technology Rail, including the latest automated visual inspection systems. These systems can automatically measure and report on the following:

• Wheel flange height, flange width and diameter; • Wheel ovality; • Wheel impact loading; • Brake pad thickness; • Pickup shoe thickness and set-up height. • Pantograph uplift;

Typical installations and their outputs are shown below:

Brake pad measurement Wheel profile measurement Wheel ovality measurement Wheel impact measurement

Figure 1: Typical condition monitoring installations and outputs The usability of the output is mixed, with some systems able to provide highly processed reporting that can readily translate into action, whilst others need more experienced human interpretation and decision making. User abilities vary too with some companies having the technical staff available who relish using the data and who are pushing forward the necessary process change to obtain benefits. Other companies are short on technical resource or require it for other work and do not have the time to use much of the systems they have bought. Even where system use is good it tends to rely upon the enthusiasm of a key user and when, inevitably they move on the benefits from the system can be lost.

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There is clearly a benefit in a system that can provide a large amount of decision support to users and ideally a system that will automate a large part of the process of turning monitoring data directly into maintenance action. Current use of Information Technology in rail vehicle maintenance The fragmentation of the UK rail system has not provided an ideal context for maximising the benefits of new technology for the maintainer. Train operators for example may do all, some or none of the maintenance for the assets they operate. Since privatisation, some of these UK businesses have pursued the implementation of new technology and IT systems in order to reduce costs, improve business efficiency and improve asset reliability performance. Some have simply retained the base systems inherited from British Rail. Typical UK operators can use up to 100 different IT systems during the normal course of their operation. This has resulted in a plethora of non-standardised systems that require time and effort to use, interpret and deploy. This has led to much inefficiency and the benefits that UK maintainers should be realising from new technology have been sub optimised. Clearly, the development of any system to provide the automatic conversion of monitoring data into maintenance action is not straightforward given the mixture of systems to which it must interface. Decision support solutions AEA Technology Rail, as a supplier of condition monitoring equipment, has been working with industry partners to help them realise the potential benefits from such equipment [1]. In order to provide a solution that would help users realise more of the potential benefits, AEA Technology Rail sought to produce a product that would provide decision support. This resultant information would be produced after automatically analysing data from many different sources and producing optimal reporting to the maintainer, within the system that they use on a daily basis. The product, known as Xe@™ (shorthand for the Latin word exeat, meaning “let it go free”) would need to be very easily configurable and have the ability to place simple information into other software management systems. Figure 2 below shows the basic concept.

Figure 2: Xe@™ Decision support software conceptual systems diagram

Maintenance Management System

Application for Alstom Transport TLS Alstom Transport TLS have been using the latest automated visual inspection equipment to provide wheelset, brake and current collector shoe monitoring for their West Coast, Northern Line and Chester UK operations for the last 5 years. Alstom Transport TLS agreed to conduct a pilot for the decision support software, which would prove the concept and identify user issues and business benefits. In order to make the pilot manageable the scope of input was restricted to the management of wheelsets. It was decided to use the local Class 323 fleet as the Xe@™ pilot subject as this would potentially provide information more rapidly than the newer Class 390 fleet. The pilot scheme commenced in March 2004 and was designed to run for 6 months. Existing TreadVIEW® installations were used to supply wheel profile parameters: flange height; flange width and wheel diameter and advise on condition as wear increased. Additionally, Roundchex® was provided at Longsight depot to monitor wheel ovality. Both TreadVIEW® and Roundchex® utilise a software system called IDS for reporting. There is also a Wheelchex® site installed on the running route for the fleet which measures wheel impact load and is reported through the Network Rail control centre, who receive advice from a software front end called IChex®. Wheelchex® data had to be entered manually as the system had yet to include an automated vehicle identification (AVI) provision to match vehicles to wheel impact loads. (Infrastructure managers, Network Rail, are evaluating vehicle tagging options at the time of writing that would enable this). For comparative evaluation purposes, manual inspection records were also entered into Xe@™. Beyond the original scope of the project, both AEA Technology Rail and Alstom Transport TLS had identified future potential benefit in linking the Xe@™ system with:

• The local wheel lathe; • The PadVIEW® brake pad inspection, analysis and reporting system; • the SAP maintenance and financial management system.

This scope is illustrated in figure 3 below

Figure 3: System configuration for Xe@™ pilot scheme at Longsight For the pilot scheme, interviews were held with key staff within the maintenance process to understand in detail how they did their job, what reporting format would best suit their needs and how this could be

Xe@™

effectively delivered. The requirements from Railway Group Standards and Vehicle Maintenance Instructions in addition to corporate and local practice were also considered. As this initial pilot scheme would not report into SAP, a web-based series of reports, available on the Alstom Transport TLS Intranet were devised. For each report, the targeted staff in the process were considered, this is a base principle for AEA Technology Rail’s decision support software Xe@™. If these user requirements are incorporated into decision support outputs they will theoretically increase the use of such technology and maximize the benefits gained. An example of the type of output report is shown in figure 4 below showing sample data. This simple ‘Traffic Light Value’ report has been produced by assessing the outputs of a number of separate measurement systems. The report was built on the philosophy of the existing manual inspection system and is aimed at the maintenance planners. Items that classify as RED have exceeded the wear or damage parameters laid down in the governing standards. Items that are classified as YELLOW are deemed to be close to exceeding parameters. The actual limits to classify as yellow have been defined by the maintainer based upon experience of this fleet. Items that are classified as BLUE are deemed to be just showing signs of wear or damage. Items classified as ‘no concern’ are GREEN although these are never shown in an effort to keep the information presentation simple.

Figure 4: Traffic Light Value Report from Xe@™

Lessons learnt Pilot scope - Although the principle of keeping the pilot scheme scope small to prove technical aspects and techniques is sound, the output and therefore benefit to the user, was also limited. Ideally the pilot scheme would have included automated output to SAP to provide maximum benefit in the short term. Additionally, linking in more automated inputs, from the wheel lathe for example, would have demonstrated greater system capability despite the initial increased complexity. Timescales and benefits - The relatively short pilot period of 6 months is not ideal to provide a good indication of business benefits from asset sub-systems like wheels that have long term wear characteristics, as any benefits may well develop over 3 – 5 years. Wheelchex® automation - The manual entry of Wheelchex® data is obviously less than ideal in a system whose benefits are derived from automated decision support. This automation is relatively simple to achieve technically and AEA Technology Rail already deploy this methodology in the Panchex®

automated pantograph inspection equipment. However, Network Rail are considering proposals to achieve this automated output at the time of writing. Visual outputs - The effort to understand the role of the maintainer thoroughly and incorporate that into output design was very successful. Users have commented very positively on the intuitive look and feel and the need for minimal training to use. Conformance with emerging standards - Emerging Railway Group Standards that require the maintainer to more formally record wheelset history including measurement parameters, will strengthen the value of such systems in the future. Accessibility and flexibility - Pilot users have commented very positively on the ability to receive automated evaluation of complex inputs from disparate condition monitoring systems. This will give the maintainer invaluable time to concentrate on making decisions and actually managing the asset better. The web-based access the system provides allows geographically disperse staff to understand asset performance at a subsystem and component level without significant effort. The consideration of maintenance processes and activities in the Xe@™ system design is a key feature for Xe@™. The product has been developed on a platform that already provides maximum configurability, with interface capabilities to industry standard systems like SAP, and now to AEA Technology Rail’s own condition monitoring products. It is possible to relatively rapidly reconfigure Xe@™ for new asset subsystems and provide wide geographical system access. Overall it was a successful trial in that it proved the principle and identified the practical challenges of successfully implementing such a system, which are now being incorporated into further developments and commercial applications. Great interest in the problem is being shown in the UK and across Europe, although we expect customers to take time to make the organisational and process changes required to successfully implement a sophisticated product like Xe@™. Commercially driven condition monitoring One of the problems that exists when implementing an open ended and flexible system such as Xe@™ is deciding on the scope of what is to be included and evaluating the cost and value to justify it. Deciding which of the many possible aspects of the maintenance process to include in the system and setting the priorities for implementation is not straightforward. The pilot system described above set its scope mainly by looking at what data was readily available and could be included quickly. Whilst this is fine in order to prove the technical feasibility for a pilot a more robust, commercially driven approach is needed if real value is to be provided. As a monitoring system supplier AEA Technology Rail is frequently involved in supporting customer’s production of business cases to justify investment, particularly for automated visual inspection systems. Over the years quite detailed models have been developed to calculate the savings offered by systems in a range of areas. This understanding of the relative value of monitoring information holds potential to help with Xe@™ implementation. The approach is interesting in a number of respects as modeling shows:

• There can be large variations between applications, dependent upon fleet size, vehicle type and contractual arrangements for maintenance, so general suitability can be quickly assessed.

• When the savings areas are quantified the results often surprise people by being much larger or smaller than they imagined. Some bigger benefits are less obvious, but can now be prioritised.

• There are usually only two or three key benefits that dominate the business case, helping set priorities for implementation.

• The benefit of monitoring different components can be compared, helping set the initial scope of what to measure. For example, the overall value of monitoring brake pads is usually greater than that of monitoring wheels, as pads are often a high cost consumable item, inefficiently used and a constraint to extending maintenance intervals.

Typical savings estimates are shown in table 1 and 2 below.

Table 1: Typical Brake Pad Monitoring Cost Saving Assessment

Table 2: Typical Wheel Profile Monitoring Cost Saving Assessment So, in addition to providing information to justify investment, this type of assessment helps prioritise elements for automation with Xe@™. Clearly effort should be directed at the most valuable and easiest to realise areas first. Conclusion Railway maintenance is beginning to realise the potential from joined up IT and condition monitoring systems that provide benefits in the form of reduced costs, reduced effort and improved performance in many areas. The focus on getting more from installed systems, particularly in the UK, is intensifying, especially as data exists that should be providing more to the maintainer. The pilot scheme to understand the benefits that could be achieved from joining up wheelset condition monitoring systems has successfully proved the feasibility of achieving these benefits and provided practical experience to shape the delivery of these benefits in commercial applications. The benefits to maintenance engineers from deploying new technology should be enhanced by intelligent decision support software that makes proactive maintenance easier. The overall benefit of the decision support technology is to provide the maintainer with a greater ability to micro manage asset subsystems and components, without the necessary skilled labour that would otherwise be required. A benefit is derived from providing information to the point where a maintainer carries out their day to day activity, their maintenance management system or regular IT systems for example, releasing resource from time consuming analysis given the many outputs that exist. The ability to collate and use the many data sources that exist in the rail system will inevitably provide added value from information that would

Typical Brake Pad Monitoring Cost Saving Assessment (Savings per annum for a 200 vehicle EMU fleet)

1. Savings in pad life extension £80,000 2. Savings from rectifying high wear rate pad positions £9,000 3. Changing brake actuators 'on failure' not overhaul £70,000 4. Reducing brake test costs £6,000 5. Extending examination intervals £90,000 6. Better adherence to pad change limits £3,000 7. Labour savings on pad inspection and changing £12,000 8. Increasing train service resilience £20,000 9. Improved engineering decision making £5,000 Total £295,000

Typical Wheel Profile Monitoring Cost Saving Assessment (Savings per annum for a 200 vehicle EMU fleet)

1. Reduced train availability penalties £10,000 2. Labour savings on routine gauging £40,000 3. Ensuring wheelsets meet overhaul (paid for by lease company) £60,000 4. Reduced disruption due to unscheduled moves £10,000 5. Wheel lathe operating improvements £5,000 6. Exceptionally high wear rate mitigation £15,000 Total £140,000

otherwise be lost to the maintainer. The Xe@™ product now forms a key enabler in AEA Technology Rail’s Advanced Asset Maintenance (AAM) suite. Understanding business value and potential savings to customers is essential to help focus implementation, prioritising areas of greatest value. Reduced technical resource within train maintenance companies has made the involvement of the system supplier in supporting implementation more important. The system supplier has the technical knowhow of what the system can do and the customer understands the maintenance process, a good basis for partnership, though a close and open relationship is necessary since savings often relate to commercially sensitive contractual arrangements, including penalties and bonuses. The gradual privatisation of railways around the world has often led to the contracting out of vehicle maintenance, allowing train operators to focus on their core activities. The train maintainer is often not the owner of the asset they maintain and may not even be responsible for the full maintenance cost, with items like periodic overhauls often being outside of the maintenance contract. Developing this thinking further, the ownership of condition monitoring equipment is evolving. Since what the customer wants is really only the information the system provides, the opportunity exists for the system supplier to offer information on a purely data provision basis and retain full responsibility for the system himself including installation and support, placing risk and ownership where it is best managed. In many situations the business cases for the implementation of AAM demonstrates very high returns, so a rapid and effective implementation is vital. A natural evolution is to take the partnership between system supplier and train maintainer forward on a risk and reward basis with incentives based around delivering the key areas of the business cases, usually materials savings and vehicle availability improvement. With solutions to most of the technical and process automation issues now available the next step is likely to be a commercial one, with suppliers truly sharing the risk and being incentivised to partner with train maintainers to help in really delivering the promise. Acknowledgements The author would like to thank Alstom Transport TLS for their participation in the Xe@™ pilot implementation and colleagues at AEA Technology Rail involved with the work. References [1] A. Jones, P Ryan. “Maximising the benefit from condition monitoring and other data sources through

designing decision support systems for the maintenance engineer”, IMechE Seminar: Railway Maintenance and Refurbishment, (2004).