Best Practices in Maintenance Planning And Scheduling

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Effective Maintenance Planning and Scheduling is a requirement not an option if one wants to optimize the effectiveness and efficiency of their maintenance workforce. Yes, identifying the right work is key however without effective maintenance planning and scheduling work execution will not be as effective and efficient.

Maintenance Wrench time is directly impacted by the effectiveness of maintenance planning and scheduling (Wrench time is the amount of time a maintenance person has their "hands on tools". World Class ranges from 55-65%)

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Best Practices in Maintenance Planning And Scheduling

  1. 1. Planning and SchedulingWarning: One who reads this chapter should have an understanding of Chapter 1.1 -Maintenance Function first in order to fully comprehend how planning and schedulingworks.The goal in this section is to present a concise description of the planning and scheduling processin order for Reliability Engineers to become familiar with the process and know how to interact withit in order to leverage their reliability improvement efforts. In order to keep it short, I will keep thisat a very high level and only delve into more detail where it will be of particular interest to theReliability professional.A properly designed and executed P&S (Planning and Scheduling) system can be one of the mosteffective means available in aiding reliability initiatives and inculcating reliability practices into thedaily execution of maintenance activities. As a Reliability Engineer you will be well served to havea good understanding of how maintenance planning and scheduling works ideally, as well as how ithas been applied in your plant. Most importantly, by understanding the P&S process, you will thenunderstand how you can use it to leverage your reliability improvement efforts.The purpose of any P&S system should be to eliminate delays in the maintenance process andcoordinate the schedules of the maintenance resources and the production schedule. You maywonder how a process with these goals can be of interest to reliability professionals, however if youwill continue, I will attempt to show you how P&S not only aides reliability initiatives, but how theyform a complementary relationship and flourish when implemented together. In the following text Iwill discuss the P&S process in the same order that a work order flows through it and will attemptto illuminate the areas where reliability can be leveraged.
  2. 2. All jobs are not good candidates for planning. Very simple jobs do not have much value that canbe added via planning so they normally would not go through the planning process. This practicefrees the Planner up to focus on jobs where planning can leverage his time by two or even threefold. Additionally, jobs that have low predictability are not good candidates since a Planner wouldnot be able to accurately predict the resource and part needs for the job. Every organizationinvolved in a P&S effort should identify the jobs that should not be planned. However, all jobs aregood candidates for scheduling as long as a reasonable time estimate can be made.As far as P&S is concerned there are two basic types of work, 1) urgent work and 2) non-urgentwork. Sounds simple enough, but the key difference is urgent work must be attended to withoutdelay, whereas non-urgent work allows a window of opportunity to take the time required to planand schedule the work and given that time a tremendous savings can be created and that is theultimate goal of P&S. Urgent work is fraught with delays, misdirection and confusion, but by itsvery nature we cant take the time to investigate the needs of the job, estimate the resources,develop a plan and obtain the necessary parts that will be needed. Instead, we run headlong intothe fray and figure out what we need as we go. And sometimes we have to back up and try adifferent route. As you recognize, this approach adds an unnecessary cost to the job, but whenproduction has been put on hold or threatened you must demonstrate a bias for action. Putting anend to work such as this is a goal that is common to both Reliability and Planning and Schedulingand the two should be linked together.The primary roles in a P&S system are the Planner, the Scheduler, and the MaintenanceCoordinator. In general, the Planner identifies everything that will be needed to execute the job,the Scheduler arranges and communicates all timing aspects of the job, and the MaintenanceCoordinator enables maintenance to attend to the most important work at the optimum time relativeto production scheduling. Usually the Planner and Scheduler both report through the Maintenancedepartment whereas the Maintenance Coordinator should report through the Operatingdepartment.Some organizations will have one or more persons assigned to each of these roles and at the otherend of the spectrum some may have individuals responsible for more than one of these roles.Either situation can work effectively as long as the roles are looked at as distinct and ample time isallotted to fulfill each individual role. We will now embark on our journey through the P&S process.As maintenance work requests are made from the Operating department or they are identified apotential failures on the PF Curve (see charts below), it should be a continual process for them tobe "funneled" through the Maintenance Coordinator.
  3. 3. Planning and Scheduling Using the PF Curve – See below for PrioritiesAs I mentioned above, one of the Maintenance Coordinators primary tasks is to enableMaintenance to work on the most important work. When all work for a given maintenanceorganization goes through a single Operating department person (the Maintenance Coordinator)priorities can be leveled and unnecessary or duplicate work request can be eliminated. The benefitthis provides to the Maintenance organization can not be overstated. Rather than having everyonein the Production department who initiates maintenance requests setting priority based on theircurrent needs and limited perspective, a Maintenance Coordinator who has a larger perspective byvirtue of seeing all maintenance requests and knowing the overall production scheduling needsand constraints can provide a much clearer focus for the Maintenance organization to respond to.The Maintenance Coordinator will delete unnecessary or duplicate requests and adjust thepriorities of the remaining work request to reflect the needs of the production department whilerecognizing the limited capacity of the maintenance organization before the requests are sent tothe Planner.The Planner is next in line to receive the work request once the Maintenance Coordinator hasperformed his review. The Planners most important role is to identify and quantify the resourcesthat will be required to execute a given job. Categorically, these resources are 1) number of
  4. 4. maintenance personnel and man hours required for skill level and crafts required, 2) steps requiredto complete the job, 3) part needs, 4) tool and equipment needs, and 5) information needsincluding drawings and specifications. In so doing, Planning prevents most delays frommaterializing and thereby greatly improves maintenance effectiveness. The Planner is usually oneof the best craftsmen who also has the additional skills of excellent written communication,information management, computer skills, managing multiple priorities, and is methodical and wellorganized, to name a few.The Planner will review the work requests to see that they are written on the correct item in theCMMS, otherwise correct them and then determine if he will need to do a field visit or not. ThePlanner should conduct a field visit on any work that is not obviously routine and straight forward.During a job site inspection the Planner will identify the resources required by the job and also noteancillary repairs/equipment needs that should be resolved during work order execution. Any otherdelays that are likely to be present will also be noted. Sources of other delays can be 1) jobpreparation, 2) permits, 3) lock out/tag out, and physical access problems to name a few. ThePlanner will determine how best to prevent each identified delay from materializing and take thesteps necessary to prevent the delay. For example, a job may have very difficult access thatscaffolding could resolve; the Planner identifies the need for scaffolding and an estimate of the timethat would be required to erect the scaffolding. All of this information will be documented in astandardized form called a Job Plan for each planned work order. In this example, when the jobcame up to be scheduled, the need for scaffolding would be recognized and the job would bescheduled allowing sufficient time for the assembly of the scaffolding. If the Planner believes that aparticular job is likely to be repeated again and again in the future he will likely store the plan, thuscutting the time required for him to process similar work orders in the future. It will serve theReliability Engineer well to familiarize himself with all "Stored Plans" on equipment involved in areliability focus. Sometimes stored plans are for a particular piece of equipment, but more oftenthey will be for a category of equipment. An example of the second type would be a stored plan torebuild an ANSI mark III group 2 pump which could apply to dozens of individual pieces ofequipment.For the Reliability Engineer, here is a critical point to use the P&S system to leverage your efforts.These job plans will contain instructions on the steps required to complete the job. The level ofdetail will vary, depending on the job. The instruction contained in the job plan may supportreliability or they may not. Using seal replacement as an example, if you are trying to implement aplan to improve seal life and have identified best practices you would like to see adopted in thefield, here is a good place to aid that effort. You can get with the Planner, review what he hashistorically documented for seal replacement job plans, and then amend that with your bestpractices. You may find that the Planner in the past has lacked sufficient detail, only listing themajor steps such as "replace seal". Or it could be the case that you want to specify a new sealtype or brand, or require laser alignment. The point is that if you have identified a change inpractice, second only to your communicating to the field personnel themselves, you need to workwith the Planner to incorporate the new practices into his job plans. These revised job plans willserve as an excellent reminder to field personnel of what it is you want them to do and how youwant it done. They will also help the Planner in the event that the time required to do the job will bedifferent and/or there are changes in part needs. Usually, job plans do not need to be verydetailed, but should simply remind field personnel of what needs to be done, particularly on routinejobs. The less routine the job is, the more that details should be included in the job plan.
  5. 5. Job status codes are used throughout the P&S process to segregate work into its various stagesas it is progress through the process. Common status categories are: In planning Awaiting parts Waiting for approval On Hold Ready to be Scheduled - Planning complete ScheduledThe Planner normally reserves parts that will be needed for jobs and places orders for any that willcome from off the plant site. Once the job plan is complete and all part needs have been resolved,meaning that they can be available in less than 24 hours, the job will be coded as "Ready to beScheduled" signifying that the planning phase is now complete. The on-site parts will actually beordered and all required parts put in a kit a day or two before the date the job is scheduled to start.The job will now go to the Scheduler who will, working with the Maintenance Coordinator develop aschedule that optimizes production needs and schedules to the availability and capacity of themaintenance resources. Different organizations use different strategies, some use weeklyschedules only, some only daily schedules and still others use both. The nuances of these variousstrategies are beyond the scope of this chapter, so we will just assume that a schedule is createdand communicated to all parties.A common problem reported by reliability professionals is that, too often preventive maintenancework and corrective maintenance work that was identified by predictive technologies linger in themaintenance backlog unattended until a failure develops. The scheduling process presentsanother opportunity to aid reliability and prevent this malady.Schedules are built by assigning dates to the most pressing problems first, then the large majorityof the available time remaining in the schedule is filled with jobs that are selected due tomanagement interest, secondary importance, age, or ease of execution. It should not be difficult tomake the case for regular inclusion of reliability related work orders. Preventive maintenance andcorrective maintenance are both very predictable activities, perfect examples of work that can beeffectively planned and scheduled. Additionally, this work does not have to be done today, or eventomorrow. This being the case, you might want to provide a list each month designating the workyou would like to see scheduled some time during the month. As you well know, often you willhave a month or more to complete the work before risk to reliability starts to increase. Thesefactors make these type tasks ideal to build an effective schedule. You should talk with theMaintenance Scheduler and the Maintenance Coordinator separately to get their perspective onthe priority given to this type of work for placement into the schedule. If you are not fully satisfiedthat the appropriate level of priority is not being given, then ask if you can start attending thescheduling meeting. Not only will you have the opportunity to lobby first hand for inclusion ofreliability related work, but will also hear first hand the reactive work that is making scheduling non-reactive work difficult. You may find new candidates for reliability improvements as well as improveyour perspective on the issues involved with keeping the plant running.Once a job is scheduled, as stated previously the parts will be kitted, placed in bin or staged in anappropriate area and the job plan package will be delivered to the individual(s) that will execute the
  6. 6. job. When the scheduled time for the job arrives the maintenance personnel will have every thingthey need for the job. The job should already be prepared by Operations, meaning that theequipment has been shutdown, flushed or cleaned if necessary, tagged out and at least ready forlockout, and the permits should already have been initiated. There should be no delays when themaintenance personnel arrive at the job site, they should only have to complete the permits andlock the equipment out before starting the job.Progress of the job should be similar with no need to leave the job site for anything other thanbreaks or lunch. Pre-work that should have been completed by other crafts, such as insulationremoval or the building of scaffolds should already have been completed. Any required helpshould arrive when needed or be prepared to arrive upon notification.When a job can be prepared for and then executed without delay, maintenance effectiveness canbe multiplied. It is not uncommon for the effectiveness of planned and scheduled jobs to be 25%or more than the same job without P&S. To see just how critical maintenance effectiveness is,consider the following: You may be familiar with a term called "wrench time". If not, this term is aunit of measure for the amount of time maintenance personnel spend doing the actual work forwhich their role is most responsible for. Wrench time is usually expressed as a percent andnational studies typically put this number between 25 and 50% for North American industries. Asan example to better define wrench time consider that a maintenance mechanic is replacing amechanical seal and doing a laser alignment on a pump, his time doing this would count as"wrench time". However, the time for which he spent leaving the job to get the seal from the storeroom and the time he spent away from the job site to obtain additional shims for aligning the pumpwould not count as wrench time. As you can now see, wrench time is a measurement of effectivetime and excludes wasted or unnecessary time. The goal is to eliminate all delays and non-productive work so that maintenance personnel can work effectively none stop, never leaving thejob once started until it had been completed, except for breaks, lunch or the end of the day. In thatideal situation the only time that would not be counted as wrench time would be things like safetymeetings, other meetings, break and lunch times, and travel time to and from the job. While thismeasure is somewhat idealistic, it does provide a clear way to assess overall effectiveness. P&Sis the most effective way to improve an organizations wrench time. The power in improvingwrench time is considerable. For example, if you have a crew of 10 people that has a wrench timeof 30% and it is improved to 40%, you will have effectively added one mechanic and this mechanichas a wrench time of 100%!When P&S and Reliability are implemented together a synergistic relationship develops. Aproperly designed and operated P&S system increases a maintenance organizationseffectiveness, causing them to be able to complete a given amount of work in less time. This shiftsthe balance of the work system creating a void to fill in the remaining time. If well thought outreliability initiatives are used to fill that void, reactive work will be reduced which in turn will leavecapacity to complete more planned and scheduled work, thus a virtuous cycle that will continue toimprove itself until a new balance point is achieved. Planning enables Scheduling and Schedulingenables effectiveness. Effectiveness enables reliability and reliability enables planning. Withoutplanning, scheduling loses its ability maximize the use of time. Without scheduling, planning lacksa means to orchestrate the activities required by the job. Without P&S, reliability related work isneglected for sake of the urgent work. Without reliability related work, the decreased flexibility inscheduling the job makes it more difficult to schedule 100% of the available manpower resources.
  7. 7. Hopefully this overview of the maintenance planning and scheduling process has given you someinsight into the value of P&S and also how you can use the process to facilitate your reliabilityefforts.

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