Maintenance and Reliability Best Practices. Ramesh Gulati
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would be thrilled to hear that their maintenance craftworkers are sitting idle most of the time waiting for breakdowns to happen. The “Maytag repairman” image of a maintenance department should not be compared with a fire department, where fewer fires to battle are better. A maintenance department can be far more productive in so many ways, becoming proactive instead of responding to emergencies like fire departments do. Maintenance departments should perform preventive and condition-based maintenance tasks, participate in process improvement projects, and work on capital improvement initiatives. Maintenance workers can upgrade their skills, train others, and educate operators to run the assets properly to minimize errors. In essence, good planning and scheduling will avoid delays and minimize wait time, other wasteful activities, and nonproductive work.
Planning and scheduling (P&S) is a disciplined approach both for utilizing maintenance resources effectively and for executing maintenance tasks such as PM/CBM or corrective maintenance tasks efficiently. This is accomplished through:
• Defining and clarifying the right work
• Prioritizing work
• Developing the work sequence and steps to complete the task
• Identifying necessary tools, materials, and skill sets
• Assuring on-schedule availability of materials and assets
• Scheduling the work to be done with agreement from production on the scheduled time
• Ensuring details of completed work are documented in CMMS
A work plan is the key deliverable of the planning process. This product is where the largest gains in productivity can be made. In some organizations, a single person provides both planning and scheduling functions. In larger organizations, these functions are often split, allowing additional resources for each role.
To move from reactive to proactive maintenance, at least 80% of the work should be planned on a weekly basis. Compliance with this work schedule should be at least 90%.
In this chapter, we will discuss the “what and how” of planning and scheduling maintenance tasks so that they can be executed effectively as well as some associated topics (workflow and roles, work categorization and priority, turnarounds, etc.).
Asset Criticality (AC)
Asset criticality is a ranking of factory/plant assets according to potential operational impact. Criticality supports prioritization of assets that are important to monitor and should be maintained at an agreed-upon level of maintenance based on the consequences of failure.
Bill of Material (BOM)
A list of materials needed to complete a particular assembly or fabrication job. The BOM can also be a list of items necessary to support the operations and maintenance of an asset or component.
Computerized Maintenance Management System/ Enterprise Asset Management (CMMS/EAM)
A software system that keeps records and tracks all maintenances activities, including maintenance work orders, PM schedules, PM masters, material parts, work plans, and asset history. Usually, it is integrated with support systems such as inventory control, purchasing, accounting, manufacturing, and controls maintenance and warehouse activities. Newer integrated systems are known as EAMs.
Coordinators
Individuals who oversee the execution of all work within a facility, including maintenance. They are accountable to the asset or process owner for ensuring that the asset or process is available to perform its function in a safe and efficient manner and to help prioritize the work according to the operational needs.
Planned Work
Work that has gone through a formal planning process to identify labor, materials, tools, work sequence, safety requirements, etc., to perform that work effectively. This information is assembled into a job plan or work package and is communicated to craftworkers prior to the start of the work.
Planner
A dedicated role with the single function of planning work tasks and activities.
Planning
The process of determining the resources and methods needed, including safety precautions, tools, skills, and time necessary to perform maintenance work efficiently and effectively. Planning is different from scheduling. In short, planning defines what and how, whereas scheduling defines who and when.
Preventive Maintenance (PM) Schedule Compliance
The number of PM work orders (or labor hours) completed, including PdM/CBM, divided by the total number of PM work orders (or labor hours) scheduled during a specific time period.
Schedule Compliance
A measure of adherence to the schedule. It is calculated by the number of scheduled jobs (or scheduled labor hours) actually accomplished during the period covered by an approved daily/ weekly schedule, expressed as a percentage.
Scheduled Work
The work that has been identified in advance and is logged in a schedule so that it may be accomplished in a timely manner based upon its criticality.
Schedulers
Individuals who establish daily, weekly, monthly, and/or rolling yearly maintenance work schedules of executable work in their facility. The schedule includes who will perform and when the work will be performed. The schedule is developed in concert with the maintenance craft supervisor and operations.
Scheduling
The process of determining which jobs get worked on, when, and by whom based on the priority, the resources, and asset availability. The scheduling process should take place before the job is executed. In short, scheduling defines when and who executes the work tasks.
Turnaround
The planned shutdown of equipment, production line, or process unit to clean, change catalyst, and make repairs, etc., after a normal run. Duration is usually in days or weeks; it is the elapsed time between shutting down the unit and putting the unit onstream/online again
Work Order (WO)
Paper or electronic document specifying the work needed on an asset. A work order is a unique control document that comprehensively describes the job to be done, including a formal requisition for maintenance, authorization, and charge codes.
Work Order Parts Kitting
The collection and staging of parts required for each individual work order. This step is usually accomplished in a plant’s storeroom within the maintenance shop. Each kit is identified by a number or label so that it can be staged or delivered to the right maintenance crew.
Work Plan
An information packet, sometimes called a job or work package, provided to the worker; it contains job-specific requirements such as task descriptions sequenced in steps; job-specific instructions; and safety permits/procedures, drawings, materials, and tools required to perform the job effectively.
Figure 4.2 illustrates a simple maintenance workflow process. There are three types of work:
• PM—work that includes CBM/PdM
• CM—new work resulting from PM/CBM activities
• CM—breakdown/emergency work (reactive work; usually no planning is done)
Preventive maintenance (PM) work should have already been planned, therefore going directly to scheduling. Corrective maintenance (CM)—breakdown/emergency work—can be executed while bypassing the planning process, and sometimes even the scheduling process based on its urgency, depending on whether there is enough time to plan this type of work.