Maintenance and Reliability Best Practices. Ramesh Gulati
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Wrench time is the primary measure of workforce efficiency and planning and scheduling effectiveness. Work that is planned before assignment reduces unnecessary delays during jobs, and work that is scheduled reduces delays between jobs. Schedule compliance is the measure of adherence to the 1-week schedule and its effectiveness.
A major downtime that “just happens” can be disastrous for a plant. A planned shutdown can provide maintenance organizations an opportunity to identify and address major potential problems or failures in a timely manner to improve plant safety and efficiency. Usually, a system or a process is shut down until the requested and specified work is completed and then restarted, thus “turning around” the process/plant. Examples of this type of work can be relining a large furnace, overhauling and upgrading an assembly system, replacing turbine or compressor blades, cleaning and upgrading a chemical reactor, or replacing process tanks. In a production facility, a turnaround usually consists of combinations of investment projects, maintenance projects or overhauls, and typical maintenance activities such as PMs or corrective maintenance activities that require the plant to be removed from service.
All the major heavy metal and process industries—steel mills,refining, petrochemicals, power generation, pulp and paper, etc.—have their own nomenclature for their maintenance projects. These are called turnarounds, maintenance shutdowns, planned outages, or just maintenance repair projects.
Shutdowns for scheduled major maintenance work and large capital investments are the most expensive and time-consuming maintenance projects because of the loss of production and the expense of the turnaround itself. They can be complex, especially in terms of shared resources; as the complexity increases, they become more costly and difficult to manage. Scheduled shutdowns usually are of short duration and high intensity. They can consume an equivalent cost of a yearly maintenance budget in just a few weeks. They also require the greatest percentage of the yearly process outage days. Controlling turnaround costs and duration represents a challenge.
A shutdown always has a negative financial impact. This negative impact is due to both losses of production revenue and a major cash outlay for the shutdown expenses. The positive side is not as obvious; therefore, it is often overlooked. The positive impacts are an increase in asset reliability, continued production integrity, investment in infrastructure,and a reduction in the risk of unscheduled outages or catastrophic failure.
Scope management is one of the major challenges in a turnaround. The scope will change, sometimes dramatically, and it will impact the schedule. Typically, the scope is developed based on information gathered from operating parameters, capital investments, preventive maintenance actions, and predictive tools. Sometimes, we don’t have a good understanding of the scope until an asset or system is opened for inspection. As an asset is opened, cleaned, and inspected, the extent of required repairs can be determined and planned.
There are distinct differences between turnaround maintenance work and capital projects. Work scope is well defined in capital projects;however, in turnarounds, the scope is dynamic and fluctuates a lot. Figure 4.12 lists the major differences between capital projects and turnarounds.
Identifying and appointing a turnaround planner well in advance,maybe 6–8 months, is a good practice. This planner helps to develop the scope, integrate the full scope of work including resources, and assure readiness for the execution of the turnaround. Similarly, identifying and appointing a turnaround manager well in advance, maybe 3–4 months,is also a good practice. The turnaround manager should have the delegated authority to lead the turnaround effort to a successful conclusion. In some organizations, new turnaround managers and planners get appointed just after completion of the last turnaround, as an ongoing process to begin planning for the next turnaround. Lessons learned from the previous turnaround are then transferred to the planning and execution of the next turnaround.
FIGURE 4.12 Capital Projects versus Turnaround Maintenance
The following is a suggested checklist for a turnaround manager:
• Identify the rough scope of the work and resources required,specifically who will be planning, scheduling, and supervising the work.
• For scope finalization, work with key players to identify the scope as soon as possible. As a minimum, freeze the scope 4 weeks before the start of a turnaround, depending on the size and complexity of the turnaround. There will be changes. Accommodate them as they arise within the contingency allowances of the turnaround. Significant additions that exceed contingency plans require revisiting the total scope of the work and authorization of changes by the stakeholders.
• In planning work, plan the work and prepare job packages with the help of planners and craftworkers who are familiar with the work/area.
• Ensure the work plans have been reviewed by the assigned craft supervisors from an execution point of view.
• Ensure that all drawings, repair instructions, and required material have been identified and updated and that their availability has been validated. Check that arrangements have been made to stage the material at the proper location.
• Check that special tools and lifting devices (e.g., forklifts, a mobile crane of correct capacity) have been arranged and will be available at the site on the scheduled day. Make sure that lift plans, equipment capacity, and condition for service have been validated prior to scheduled lifts.
• In scheduling work, break large work into smaller work tasks and then schedule them based on resource availability and duration of the shutdown. Schedule all work to be completed in 90% of the approved duration. Leave 10% time as a contingency.
• Identify “critical path” tasks that can impact the overall schedule and focus your attention on them.
• Make sure all material, tools, cranes, etc., have been arranged to be delivered at least 1 day before the start of the shutdown.
• Ensure that all the necessary permits have been procured and that the lockout and tagout plans have been arranged to provide for safe, efficient access to the scheduled work.
• Establish a communication system. How is work accomplished? Once problems have been encountered or uncovered and corrective action is taken, how will this information be communicated, and how will feedback be provided in a timely manner? For large and critical tasks, communication may be necessary on every shift. Arrange to meet face-to-face with task leaders, planners, and schedulers on a daily basis for schedule execution and on a weekly basis to review progress and change in direction, if needed. The schedule is intended to accomplish the overall goals while maintaining enough flexibility to accomplish minor changes.
• Arrange a face-to-face meeting with all your key players,including operations personnel, to discuss the goal and schedule of the shutdown. Make sure they understand the cost of this undertaking and the impact of delays. Emphasize safety and quality of work. This meeting should be held a few days before the start of the shutdown. At a minimum, the operations personnel should be included in the weekly progress reviews.
• On the first day of the shutdown, make sure that all safety measures are taken in shutting down the system and that appropriate personal protection equipment is used. All lockout/tagout measures should be completed properly.
Attention to the following items may be required and appropriate corrective action planned:
• Barricades. These should be considered to restrict the movement into or the presence of people in restricted areas where overhead lifting, high voltage, radiography, and hazardous materials may be present. Ensure that proper safety signs are displayed in appropriate areas.
• Dust control management. A large shutdown can also be the source of excessive dust, depending upon the area and work to be accomplished. Make necessary arrangements to control