A Reliable Approach To Maintenance
BMT's Art Couper discusses techniques that can improve the long term reliability of the UK’s rolling stock fleet and that can notably reduce maintenance costs by at least 10%.
The UK rail industry has undergone a radical transformation over recent years to become one of the safest, most reliable and most punctual rail networks anywhere in the world. Currently, 1.3 billion journeys are made on the UK’s railway each year with 100 million tonnes of freight transported by rail between ports, factories and logistics hubs . With passenger demand set to double over the next 30 years and freight demand to increase by 140%, there is increasing pressure to ensure operating companies can maintain a robust and reliable service, while striving to improve availability and punctuality.
Art Couper, Senior Consultant at BMT Asset Performance, a subsidiary of BMT Group Ltd, discusses how structured maintenance optimisation using techniques such as Reliability Centred Maintenance (RCM) can not only improve the long term reliability of the UK’s rolling stock fleet, but can notably reduce maintenance costs by at least 10%.
Today, more people travel by rail than at any point since the 1920’s. However, such growth in popularity is resulting in significant pressure to ensure the network can cope with this demand. With an aging infrastructure and fleet, maximising reliability has become one of the biggest challenges for the industry.
Investing in new trains isn’t always the answer. Not only can major Cap-Ex be prohibitive, but the sophisticated technologies that now come with a new fleet can introduce complexity with greater opportunities for system failures to occur. In fact, recent moves to bring Class 20, 37 and 47 locomotives back from preservation or storage to mainline service demonstrates that with the right maintenance, assets can continue to perform, long beyond their design life.
If investment is to be made in new rolling stock, addressing the importance of reliability within the design phase is crucial to minimising the opportunities for failures.Expand to read the full article
Where does Reliability come from?
Reliability initially comes from the design and the build quality. If you have a good design then it stands to reason that you will have a reliable piece of equipment, providing that the design is translated into a good build, i.e. ensuring that good quality materials that meet the appropriate standards are used. Furthermore, during service, reliability will not be retained at its inherent level unless appropriate preventive maintenance is carried out.
What drives maintenance costs?
There are two main types of maintenance:
• Preventive Maintenance – carried out at a chosen time when manpower, facilities and spares are readily available. This should ideally represent approximately 80% of maintenance
• Corrective Maintenance – may require a train to be recovered back to depot and a replacement train brought into service. This is likely to also attract penalty minutes and maintenance that must be carried out when manpower, facilities and spares are not readily available. This should ideally represent approximately 20% of maintenance.
Getting the balance right is key to ensuring optimum maintenance – it’s not only the most reliable train you will have, but it will be the most cost effective to run. One unexpected faulty train that needs to be recovered could quickly result in your corrective maintenance costs escalating. There’s also the reputational cost. If a company has experienced ongoing reliability issues then it is likely to be more difficult to re-lease these trains at the end of the current lease.
What is Reliability Centred Maintenance?
Reliability Centred Maintenance is a process to ensure that systems continue to do what their users require in their present operating context. It is generally used to achieve improvements in fields such as the establishment of safe minimum levels of maintenance. Successful implementation of RCM will lead to increase in cost effectiveness, reliability, machine uptime, and a greater understanding of the level of risk that the organisation is managing.
The other option is to carry out a Performance Improvement Programme (PIP) which helps to address the known faults and reduce maintenance costs quickly. A PIP should be conducted when the existing preventative maintenance is considered to be adequate but there is poor reliability. This approach will identify the key systems responsible for the poor reliability and identify improvements by reviewing operations, preventative maintenance (system RCM analysis) and modifications. This approach enables the benefits of RCM to be obtained without the time consuming full RCM or SMR requirements, providing results quickly. This may be considered where the fleet is small and the available budget to make improvements is limited. A PIP is carried out using the following steps:
• Analyse failure data to identify the worst performing systems/equipment
• Analyse these systems looking at any operational issues involved, carrying out RCM and making recommendations for modifications (in that order of priority)
• Identify changes necessary and implement them.
Both of these approaches involve a robust, structured and auditable process. BMT has worked at all levels in the rail industry, alongside both Train Operating Companies (TOC) and Rolling Stock Operating Companies (ROSCO), in the UK and abroad. The company played an instrumental role in writing the original UK National Fleet Reliability Improvement Programme (N-FRIP), the Twenty Point Plan Document (CR/TP1203) for the Association of Train Operating Companies (ATOC), and continued to support the latter until Issue 2.
Through asset optimisation, BMT assists its clients in developing optimal solutions by analysing designs - focusing on improving reliability and availability. Availability is analysed and increased by formulating and delivering optimised maintenance strategies at vehicle and fleet levels. BMT delivers maintenance optimisation for clients by developing the most cost effective and worthwhile preventive maintenance regime for rolling stock and associated equipment using an approach utilising knowledge and expertise gained in other industries and in particular Reliability Centred Maintenance (RCM), a methodology originally developed in the aerospace industry. Using this approach, BMT has achieved significant benefits for its rail clients, with a significant improvement in reliability performance coupled with a 30% reduction in preventive maintenance workload for one fleet of electric locomotives.
One example of where BMT has helped to further improve maintenance planning to achieve optimised availability and operating costs is its work with VIA Rail Canada. Focusing on the train operator’s newly refurbished fleet of GPA-30H locomotives, BMT recently carried out a Reliability Centred Maintenance (RCM) analysis of the locomotive and its sub-systems including the newly installed Head End Power generating set. One output of the RCM study was to identify and add to the condition monitoring procedures and techniques that are currently used by VIA Rail Canada, in order to develop an optimised Condition Based Maintenance strategy.
Bob Becker, Director of Technical Services and Chief Engineer for VIA Rail Canada comments: "We were delighted to have BMT on board. The company brought a unique mix of experience and knowledge in carrying out condition monitoring tasks on our rolling stock. BMT's customer focused approach from initial study to final report places VIA Rail on the correct track for optimised maintenance procedures, cost effective Condition Monitoring techniques and our ultimate goal of full Condition Based Maintenance. The initial recommendations have already produced significant cost reductions for the generator set overhauls, with more locomotive savings to come in the future.”
A full RCM or Strategic Maintenance Review (SMR) should be conducted when it is considered that the existing preventive maintenance is inappropriate and possibly carried out at inappropriate intervals. This is likely to be the case where there has been no recent thorough review carried out (within the last 10 years). One such example is the Class 91 locomotive fleet where RCM was applied. This allowed the particular Rolling Stock Operating Company (ROSCO) to double the reliability and remove one Heavy Repair from the life cycle of each locomotive. Notably, this is a time intensive activity which provides potentially strong benefits but does take longer to complete and in turn, reap the benefits. It is necessary however if a change to the overall maintenance strategy is required.
BMT is also working with a new DMU fleet which is in the process of utilising RCM to help extend Level 1 – Level 4 maintenance and it has been estimated that the customer will secure a 33% saving on maintenance costs each year.
By using techniques such as RCM, TOCs and ROSCOs can improve reliability and reduce maintenance costs. In the face of ever increasing demand for a reliable service, it’s easy to see why maximising the reliability of the UK’s rolling stock fleet must remain top priority.
BMT Reliability Consultants
12 Little Park Farm Road
Tel: 01489 553100