Colin Findlay, Severn Unival, UK
Technically and operationally, power generation is a challenging environment. With a continually aging asset base, and an ongoing drive for maximum availability, the reliability of the plant is under constant pressure.
The nature of the business means that most maintenance and refurbishment activity needs to be carried out during outages both planned and forced. Therefore, optimizing the efficiency and effectiveness of each outage is a critical strategic objective for all plant managers. Intelligent planning and thorough preparation are mission-critical to ensure the resources are in place to balance the cost of planned reliability against the risk of equipment failure and under-performance of the plant.
Each outage is clearly a project and requires the disciplines of project management to deliver the work scope efficiently. However, it is critical to recognize that outages are also components of a longer-term maintenance programme, which is generally best managed over a 24-month cycle.
In order to achieve the optimum outcome for the business as a whole, outage management needs to have a symbiotic relationship with maintenance management. Completing an outage project safely, on time and to cost is not enough in itself. In order to be considered a success, the project work-list needs to be geared towards the over-arching objective of optimum plant performance.
It follows that any strategy to maximize power outages must be strategically linked to maintenance strategy and project delivery. They need to simultaneously operate as individual disciplines and as an integrated business programme. In addition, the maintenance manager needs to devise an enforced outage plan that enables the rapid deployment of resources to take advantage of unplanned opportunities for maintenance or repair.
Maintenance strategies: optimizing the work list
The starting point for any outage strategy has to be the work list. With an in-depth understanding of plant performance, it is possible to optimize the work list without increasing the risk of equipment failure.
Understanding how well a valve interprets and reacts to different levels of signal change can be paramount. If this valve’s role was to control small, precise changes in process it would require some attention
With modern, ‘smart’ instruments offering condition and performance information on all key assets, it is easier on modern plants to evaluate and predict the need for intervention. While the maintenance team needs to consider OEM maintenance routines on high-value critical plant, it should also follow the ‘live’ information and be prepared to make risk-based decisions, which can make a huge difference to the overall scope and impact of an outage work list.
This, of course, is a business decision, as well as a maintenance decision. It has to follow the plant owner’s strategy for risk management and specialist business risk algorithm tools exist to support such decisions. Strong and consistent use of condition monitoring and condition-based decisions over the term of the maintenance cycle will reduce the volume of tasks scheduled for each outage.
This valve responds more sensitively to upward changes in signal, but the minor oscillation surrounding the downward changes is also acceptable for this particular application
Similarly, the maintenance team needs to look at and challenge its time-based task list: Are the plant maintenance routines set at their optimum? Have the trends from previous outage overhauls been recorded, analyzed and inputted to the maintenance management system?
It is the role of the maintenance planners to seek to work proactively and dynamically with the maintenance intervals. A static policy of continuation with standard intervals is not best practice given all the modern information tools that are available. There are some excellent devices on the market to enhance intelligence surrounding the condition of critical equipment, such as Severn Unival’s transform and valve profiler systems.
Measuring hysteresis and repeatability helps provide an early indication and clearer understanding of any underlying valve problems, enhancing outage planning
Any maintenance cycle needs to be integrated with plant improvement and modernization projects. Analysis of overhaul conditions from prior outages should be geared towards reducing the work list for future years. With the right approach, it is possible to pinpoint the optimum moment to initiate an equipment upgrade that will provide durable improvements. Whenever a replacement is required, the technical decision and overall commercial value must override the direct pricing decision. On aging plant, long-term thinking is always the best management tactic.
A strategy that is geared towards extending maintenance intervals, understanding risk and seeking plant improvement to generate reliability is the bedrock of peak plant performance. Once this is in place, the plant manager can begin to think about a more sophisticated outage strategy that will further enhance operations.
The importance of planning
A simple adage for any experienced project manager is ‘planning works every time’. Basic level one planning is a given, but the really successful outage manager also plans for the dynamics of change. Project dynamics are not simply about changes to the programme itself – it draws on a broader frame of reference. For instance, the project manager must consider the varied dynamics of construction and maintenance, material delays and interfacing with wider operations.
In financially constrained times there can be pressure to reduce preparation and planning resources. For the uninitiated, it is easy for these office-based activities to be seen as a luxury rather than a necessity. However, compromising planning and preparation is false economy. Successful, maximized outage activity requires enduring integration of the maintenance strategy into the outage delivery. The plant management team and directors need to understand the importance of a medium-term programme and the value and benefits of the associated costs.
Clear long-term fiscal objectives are essential if the management team is to reconcile this dichotomy. Building a 24-month maintenance programme incorporating outages as a maintenance task delivered in a project style, by a project team underpins better performance and cost-efficiencies. This approach needs to go hand-in-hand with a comprehensive view of the supply network and its potential to act as a valuable and vital component of the maintenance strategy.
An integrated approach
On any power plant, there are key major plant areas – such as the boiler, turbine and reactor areas – that require input from specialists (OEMs for instance). The valve population should also be considered critical, as it crosses over all of the major asset areas and can significantly impact on the performance of the tier one assets. A structure that allows the best use of these specialist resources must be a central part of the planned maintenance operations. However, price drivers often take precedence and unfortunately this can mean the most advantageous partnership arrangements are not always in place.
Following a 24-month maintenance and improvement strategy, with performance data diagnostics and improvement solutions, offers the best value to the plant. Engineering improvement specialists and OEMs working closely as integrated partners within the maintenance team will deliver the optimum solution to the plant owner in the medium-term. An integrated procurement process brings further benefits. If replacement equipment can be specified and procured inline with knowledge of past performance, it will be of better quality and reliability. Well-briefed procurement partners are essential to enhance plant performance.
Regardless of the commercial dynamics, the crux of the issue is the driver of the partnership between the operator and the engineering specialist. A clear vision for the performance of the plant, aligned with a full and honest understanding of the potential for improvement, sets the scene to allow all parties to work collaboratively as one team. Creating a commercial environment that disconnects the ‘client-to-contractors’ mentality, permitting innovation and a value-based return to the contractor for its services, gets the best results from the whole outage community.
Triumph in the face of adveristy
Forced outages happen, it is a fact of power engineering life. Despite a robust maintenance regime, with condition diagnostics and a long-term asset replacement or improvement programme, it is inevitable that there will be failures that can take the plant off-line. The best that we can deliver is a continually reducing volume of forced outages. This needs to run alongside measures to ensure a quick return to service when failure does happen, having taken advantage of the window to execute parts of the work list that will further support reduction of the critical path or the costs of the prime outage.
The primary challenge for the outage manager on a major power plant is having a deliverable contingency plan in place for forced outages. It is a highly reactive time. A plant trip devours resources and costs revenue, as well as creating possible safety concerns and, in all probability, public relations issues for the operator. Nevertheless, with the right approach, a trip can also provide a valuable opportunity to deploy key maintenance activity.
From a tactical point of view, a forced outage needs to be managed in packages. Top priority is the reactive team who will be tasked to repair the failed asset and return the plant to the line. A well-organized outage manager will also be in a position to rapidly instigate a separate wave of activity focused on a set of pre-planned scenarios. Short, achievable, critical packages of work drawn from the main outage work list can be prepared for in advance and immediately actioned when a forced outage occurs. This is where the benefit of a truly integrated partnership approach with key contractors really comes to the fore. In an ideal situation, materials will be in place and a resource plan fully developed to enable efficient rapid response activity. The scenarios develop and evolve based on the ever changing work list, but it is reasonable to have between eight and ten pre-planned packages, with durations of between two and six days’ work pre-set. By programming in the needs of operations and potential permit considerations the most appropriate packages can be selected and instigated without delay.
Forced outage work programmes are slightly more expensive to execute due to mobilization costs. However, taking advantage of a window of opportunity with a pre-planned and pre-priced package will impact on the programme and cost of the main outage. Removing work from the main outage is always advantageous to reduce stress and allow the main outage team freedom to deliver, peripheral issues having been previously dealt with during the maintenance cycle.
A best practice approach
Whether planned or forced, outages are a high-octane environment. Pressures are compounded by statutory requirements, essential maintenance demands and the need for plant improvement projects. However, an intelligent power plant management strategy will ensure all outages are exploited to maximum effect and regarded as a central component of the long-term plant maintenance cycle.
Outage activity should be treated as an intrinsic part of the overall plant strategy, not as isolated projects. Activities have to be planned and executed by professional project managers, but supported by first class maintenance strategies, which drive improvement and enhance reliability. In this way, the work-list can be minimized and packaged to allow flexible planning and resource deployment.
To get the best from an outage, it is important to work closely with all those who can impact on the success of the maintenance programme as a whole. This means bringing the specialist contractor community into the team, with openness and security. Holding contractors at arm’s length will generally lead to less successful, and more expensive, outage management in the long-run. By taking a joined-up approach, power plant managers can take greater steps towards achieving the ultimate aim of peak performance.
Installation and maintenance during an outage
At a tactical level, mixing construction activity with general maintenance activity really does not work. They need to be strategically linked but physically separated, with independent programme managers running their own teams. Installing new equipment has different demands and necessities, different permits, constraints, equipment requirements and, broadly speaking, a wider variety of skills than general maintenance.
Usually, plant installations are considered critical path items, driving the overall duration of the outage and causing significant detrimental impact if they lose momentum. Having optimized the maintenance work list, the majority of maintenance activity should become a secondary programme. Having different teams focused on their key tasks, with the overall outage manager able to coordinate the changing dynamics and provide some resource flexibility ensures optimum delivery of the work list.
Colin Findlay is the Executive Director of Severn Unival Ltd the services arm of the Severn Glocon Group. Colin has an MSc in Project Management, and spent 15 years planning and executing projects and shutdowns in the Oil & Gas industry, before running an international valve service business focused on power generation markets.