Maintenance and Reliability Best Practices. Ramesh Gulati
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href="#ulink_5b08cab9-e6f2-566b-a1c9-4d45f659c38c">Planning Process
Poor planning leads to poor performance.
—AUTHOR UNKNOWN, BUT A WISE PERSON
Basics of Planning
Planning defines what work will be accomplished and how. Scheduling identifies when the work will be completed and who will do it. Planning and scheduling are dependent on one another to be effective. However,planning is the first step. The ultimate goal of the planning process is to identify and prepare a maintenance craftworker or technician with the tools and resources to accomplish this work in a timely and efficient manner. In other words, planning provides maintenance craftworkers with everything they need to complete the task efficiently.
Many maintenance engineers and managers consider planning to be nothing more than job estimating and work scheduling. This is not true. Planning is the key enabler in reducing waste and nonproductive time, thereby improving the productivity of the maintenance workforce. Many organizations have started considering planning to be an important function.
However, they realize that proper planning is not an easy task. It takes time to do it right. The time needed to plan a job properly can be considerable, but it has a high rate of return. It has been documented by many studies—including one by Doc Palmer, noted author of Maintenance Planning and Scheduling Handbook—and the author’s own experience that proper planning can save one to three times the resources in job execution. If a maintenance job is repeatable, as most are, then it is essential to plan the work properly because it will have a much higher rate of return.
Consider a maintenance shop AB where most of the work is performed on a reactive basis. The shop has no planner or scheduler on the staff. It has:
• 20 maintenance craft personnel
• 0 planner/scheduler
• 1 supervisor
• Estimated wrench time = 40%
The wrench time, also called tool touch time, varies between 25% and 65% for all industries. In North America, wrench time is, on average, around 40%.
The estimated productive work available (or performed) for AB shop per week, assuming 40% wrench time, is:
20 people × 40 hours/week × 0.40
320 labor hours/week
Now, consider another maintenance shop XY that has a reliability culture and has demonstrated a wrench time of 60%. This shop has the following staff:
• 18 maintenance craft personnel
• 2 planners/schedulers
• 1 supervisor
• Estimated wrench time 5 60%
The estimated productive work available (or performed) for XY per week is:
18 people × 40 hours/week × 0.60
432 labor hours/week
The XY shop has performed 112 hours (432 – 320) of additional work with the same number of personnel as the AB shop. This equates to a 32% increase in resources, or 5.7 more people on the staff. The increase in productivity is the result of planning and scheduling of work tasks by two people who were reassigned to handle the planning and scheduling.
But as mentioned earlier, planning requires more than just changing personnel from a craft function to a planner/scheduler function. The person must have the skills and experience to understand the different types of work and the various details that will need to be organized and assembled for that specific task (skills and resources, steps and procedures, parts, and tools).
Understanding Work
The work to be performed needs to be clearly understood. If the scope of the work has not been defined clearly, the maintenance planner must talk to the requester, visit the jobsite, and identify what steps, procedures, specifications, and tools are required to perform the job correctly. If the job is too large or complicated, it may have to be broken down into smaller subtasks for ease of estimating and planning.
Resources Required and Skill Levels
The skill level of the person required to perform the work must be identified along with the estimated hours. The job may include one highly skilled craftsperson and one or more low-to-mid-level skilled maintenance technicians. Many times, maintenance professionals believe that it is difficult to estimate the time required to perform a specific job, especially if the skills of the maintenance staff range from very low to very high with everyone theoretically at the same pay grade and position.
Therefore, planners must have a good knowledge of workforce capabilities and the environment. The skill of the maintenance workers and basic understanding and knowledge of their trade and plant assets will determine the level of detailed steps and work instructions required in the planning process. Highly skilled workforces may not need detailed instructions. Job estimating can become easier and potentially more accurate when the jobs are broken down into smaller elements. Long and complex jobs can be difficult to estimate as a whole.
A job standard database such as RSMeans standards other standard benchmarks can be used to estimate jobs. It is a good practice to build a labor standards library for specific jobs, e.g., removing/installing motors, 5–50 HP, 100–500 HP; replacing brake shoes on an overhead crane or forklift; or aligning a pump-motor unit. Predetermined motion times, time studies, and slotting techniques can be used to develop good estimates if tasks are repetitive in nature. An estimate should include work content, travel time, and personal and fatigue allowances.
The following are essential to good estimating practices:
• Be familiar with jobs and plant assets.
• Compare jobs against benchmarks.
• Be cautious when using historical data as it may have built-in delays.
• Don’t try to be 100% accurate.
It is a good practice for the planner to be a former senior craftsperson or a craft supervisor who has been given training in job estimating.
Steps and Procedures
Steps and procedures must be developed with specifications identified to ensure high work quality. The work instructions to disassemble or assemble a complex component should be clear, with sketches and drawings as needed. They should include steps at which data such as bearing clearances or temperature readings should be recorded. Human error causes more failures of assets than any other type of error in an organization.
Parts and Tools
Materials, including parts and kit lists, must be identified in order to have the parts available on-site before the job is scheduled. Special tools need to be identified in order to ensure the work is completed without delays. For example, does the maintenance person need a torque wrench to tighten a bolt instead of a box end wrench? Furthermore, the torque wrench is of no value if the torque value is not known. Inadequate information may lead to a number of self-induced failures. The objective is to reduce the likelihood that an error could occur by using the wrong part or the potential for a maintenance person to stop work to locate the right tools required for the job. A planned job template is shown in Figure 4.9.
It is a good practice to have a planning checklist to ensure that all the steps and documentation have been prepared or arranged. Figure 4.10 shows an example of a planner’s checklist.
Symptoms of Ineffective Planning
The following are some symptoms of ineffective planning:
• Maintenance people standing around waiting for parts
• High rework
• Poor work performance
•