Turnaround Maintenance Insights

How are you evolving your turnaround interval and duration setting strategies, while managing your availability performance and budget? Stretching intervals between turnarounds while also reducing turnaround event durations continue to be key focus areas for improvement-minded refiners who seek to deliver higher levels of Operational Availability (OA) while boosting process unit utilization.

Solomon’s Worldwide Fuels Refinery Performance Analysis (Fuels Study) provides a cache of key data needed to assess long-standing, as well as emerging turnaround performance trends. Solomon’s refinery unit turnaround insights have historically included the following guidance:

• Target a shorter than average duration turnaround.
• Leverage repair-versus-replace decisions to deliver turnarounds with fewer total work hours.
• Targeting turnaround intervals between 4-6 years can deliver annual days down performance that enables achieving 97%+ Operational Availability.

Refiners are on a never-ending continuous improvement quest. In our ongoing analysis of client data, we observed a subset of clients who have successfully extended turnaround intervals on key units while also delivering strong availability performance. While turnaround intervals of 4-6 years are a starting point, extending intervals to upwards of 8-10 years on certain process units has become more common and are positively contributing to improved OA and process utilization potential.

Mechanical Availability (MA) and OA are Solomon’s primary metrics for measuring a refiners’ availability performance. The world's best refineries consistently deliver greater than 97% OA. See Figure 1 for definitions of these metrics.

Solomon analyzed the most recent turnaround intervals versus OA performance of each major process unit within the United States (US), Europe, and Asia Pacific regions. We observed that US refiners are sucessfully extending turnaround intervals for select major process units while also realizing strong OA performance.

For example, in Figure 2, the first portion of the regional diagrams shows that during 2022, the Crude Distillation Units (CDUs) with Top 10% and top-quartile MA performance, operated with turnaround intervals of at least 8 years (as indicated by the dark green color), while also delivering strong OA performance (light green color). This same general observation is true for Diesel Hydrodesulfurization Units (DHYTs). For Fluidized Cat Cracking units, however, the units with the strongest MA performance maintained their most recent turnarounds interval to no more than ~ 6 years.

_{Figure 2. Diagrams of Recent Turnaround Intervals for US Crude Distilling, Diesel Hydrotreating, and Fluidized Catalytic Cracking Units}

This extended turnaround interval trend is shown for US refineries. However, refiners in both Europe and Asia Pacific have not extended turnaround intervals to the extent that US refiners have.

We have analyzed the equivalent data for all major process units, including Vacuum Distillation, Hydrocrackers, Delayed Cokers, Catalytic Reformers, Alkylation, Gasoline and Kerosene Hydrotreaters, Sulfur Recovery, and Cogeneration Units.

We regularly advocate that our clients leverage repair-versus-replace decisions to deliver turnarounds with fewer total work hours, a key to reducing the turnaround’s duration. Our clients’ reported turnaround work hours are highly correlated (R² > 0.9) with overall turnaround costs and the active control of daily actual work hours have proven to be an effective turnaround cost management handle.

So, how do the overall maintenance cost performance of those who are actively focused on reducing turnaround work hours compare to those who do not? The short answer is that proactively planning and reducing turnaround work hours is also linked with delivering stronger maintenance cost efficiency performance.

Solomon’s Maintenance Cost Efficiency Index (MEI™) includes average annual turnaround costs, along with 2-year average personnel, materials, maintenance capital, and maintenance overhead costs.

Figure 3 below depicts the relationship between turnaround work hours and overall Maintenance Cost Efficiency performance for US refiners during the 2012-2022 period. These data show that 60 of the 131 refineries that delivered top-quartile maintenance personnel turnaround work hours (mPEI_TA) performance also delivered top-quartile overall maintenance spend (MEI) performance. Additionally, 89 of the 127 refineries that delivered fourth quartile mPEI_TA performance also delivered fourth quartile overall MEI performance. The bottom line is that if you are managing your turnaround work hours effectively, you will have a greater likelihood of delivering more competitive overall maintenance cost performance.

Does the ideal T/A interval exist? If so, what is it?

• Some units’ (e.g., CDU and DHYT) turnaround intervals have been successfully extended to at least 8-years and have delivered strong OA performance.
• For more complex units (e.g., fluid catalytic cracking [FCC]), shorter, 5–6-year intervals have been needed to deliver or maintain strong high OA Performance.

What are the main drivers to deliver shorter duration turnarounds and with well-managed costs?

• A necessary condition for successful T/A strategy is for the T/A work scope to ensure that OA between cycles remains above 97%.
• Focus on reducing turnaround work hours in order to also ensure cost-effective T/A execution.
• Reducing work hours will require well-considered repair-versus-replace decisions (e.g., planning and procuring a new tube bundle/internals may be more expensive than cleaning the existing ones, but may enable a shorter duration turnaround event).

An effective turnaround is one that enables the process unit to deliver 97+% Operational Availability between events. Selecting the most appropriate turnaround interval, duration, work hours, and spend, while also implementing an effective non-turnaround maintenance program, are the main handles to deliver strong unit performance.

Solomon welcomes the opportunity to discuss how you should think about these variables for your particular refinery. Contact us if you would like to discuss turnaround strategy setting or learn more about participating in the upcoming 2024 Fuels Study to gain the insight you need to optimize your turnarounds.

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