Extending shutdown intervals could boost profitability, says maintenance expert
1 min read
Manufacturers could save significant sums by looking at the frequency of plant shutdowns and assessing whether the intervals are ideal for today's operation. That's the view of Alex Thomson, principal consultant at asset management consultancy The Woodhouse Partnership.
"For many industries, planned plant shutdowns are a fact of life. But shutdown intervals have been established with no real strategic thought process," he says. "It is common for this self-fulfilling prophecy to develop whereby you have a shutdown every year because of all the work you have to do, and you have all this work to do in the shutdown because you have a shutdown..."
Thomson (pictured) cites the example of SABIC Innovative Plastics: after working with The Woodhouse Partnership, the manufacturer extended its major shutdown intervals from two to four years, saving millions of dollars in the process.
SABIC has four polycarbonate production facilities around the world. Each facility had an annual or bi-annual shutdown with the associated costs and risks.
SABIC worked with The Woodhouse Partnership on a shutdown optimisation project at its Bergen op Zoom site in The Netherlands. Using Woodhouse's criticality methods and software from Decision Support Tools, the team identified those tasks which truly drove the need for a shutdown.
In-depth assessment meant the task list could be reduced from almost 8,000 tasks performed in a typical shutdown, to just 86 which were truly shutdown dependent. Only 32 of these activities were time-critical.
Next, the optimal interval for each critical task was determined using the software to model risk assumptions, with a value attributed to all direct and indirect costs, including health and safety, environmental or reputational consequences. Extensive 'what-if' studies by multidisciplinary teams assessed the importance of poor or missing hard data.
The results showed many tasks, in fact, had optimal intervals of four years or greater. Decision Support Tool's APT-Schedule system was used to identify the best combination of tasks with different optimal intervals, pinpointing potential bottlenecks so remedial action could be taken. The result? A four-year shutdown interval was identified as optimum and it represented annualised net benefits running into seven figures.
Thomson comments: "This shows that challenging the shutdown dependency of tasks is essential, but can only be successfully done by competent multidisciplinary teams and full cost/risk appraisal, with appropriate decision-support tools and robust methods for coping with the inevitable uncertainties and poor information. Participation of all stakeholders was crucial."
