What are the phases of a turnaround maintenance procedure?
In maintenance, a turnaround is an event where one or more assets are temporarily removed from service so that maintenance tasks can be performed. While specific turnaround procedures may differ across various plants and industries, five main phases are usually observed:
Phase 1: Definition/Scoping
Turnaround maintenance procedures are expected downtime events with anticipated durations. However, although they are expected, turnarounds still cause long periods of stopped operations. Therefore, they inherently incur losses in production. This highlights the importance of a well-planned turnaround to ensure that the time lost is spent efficiently.
In the definition and scoping phase, maintenance teams create a list of activities that will be performed on assets. For example, assets might be scheduled to undergo one or more of the following activities – performance tests, component replacements, repairs, or to standby.
The output of turnaround maintenance at this phase is a work list that details the exact activities to be performed on specific assets. A computerized maintenance management system (CMMS) is the best tool you can use to keep track of your turnaround work list.
Phase 2: Preparation
Now that a work list is available, the team can start the preparation phase by identifying what resources they will need to cover the scheduled activities. Preparation includes any material resources required, as well as knowledge and training needed for staff to perform all tasks. Staffing requirements are also important to consider. Depending on the decision of the management team, tasks can be assigned to internal or external personnel.
Aside from material and staffing resources, this phase also accounts for safety requirements and procedures that need to be checked. Some maintenance activities would require special handling to reduce risks and to avoid unexpected incidents.
Phase 3: Execution
The execution phase immediately begins with the stoppage of the equipment. Most tasks in this phase involve some form of inspection, corrective action, and testing. Tasks are then updated and removed off the identified work list (from Phase 1) as they are completed. The progress of this phase can effectively tracked using the CMMS.
Phase 4: Startup/Turnover
The next phase is the startup or turnover phase. This is both an extension of the execution phase and the transition back to normal operations.
After all tasks in the work list have been performed and the final tests passed, the startup can then begin. The startup phase is essentially an operational state, but done while being closely monitored by the support groups. When satisfactory conditions are met during the startup, ramp-up can begin. Ramp-up is the gradual process of bringing the facility back to normal running conditions. It is a crucial period that minimizes the risk of any incidents.
Phase 5: Evaluation
Lastly, the evaluation phase reconciles all tasks that have been performed. This process accounts for all costs incurred from the turnaround process and looks back to confirm that all work orders and purchase orders have been closed. Any material stock that have been left over can then be credited back for future use.
An audit is usually conducted at this phase to asses the state of each asset. Any actions identified from the turnaround procedure are also listed at this stage and delegated to the accountable units within the team. The final collection of data and observations provides insights on the plant’s safety, efficiency, performance metrics, and overall performance.