Preventive Maintenance

Presented by

Eng. Mahmoud Elsayed Abdein

Objectives:-Introduction to MaintenanceReactive Maintenance

Advantages Vs Disadvantages Preventive Maintenance

Advantages Vs DisadvantagesPredictive Maintenance

Advantages Vs DisadvantagesReliability Centered Maintenance

Advantages Vs Disadvantages

Objectives(Cont.):-Computerized PM system

MAINTENANCE AND EMPLOYING TOTAL

PRODUCTIVE WORK

Implementation of PM Program

IntroductionThe design life of most equipment requires

periodic maintenanceOver the last 30 years, different approaches to

how maintenance can be performed to ensure equipment reaches or exceeds its design life

In addition to waiting for a piece of equipment to fail (reactive maintenance), we can utilize preventive maintenance, predictive maintenance, or reliability centered maintenance.

Maintenance All activities that maintain facilities

and equipment in good working order so that a system can perform as intended

All actions necessary for retaining an item, or restoring to it, a serviceable condition, include servicing, repair, modification, overhaul, inspection and condition verification

Maintenance ReasonsReasons for keeping equipment running

Avoid production disruptionsNot add to production costsMaintain high qualityAvoid missed delivery dates

Attempt to maximize performance of production equipment efficiently and regularly

Prevent breakdown or failuresMinimize production loss from failuresIncrease reliability of the operating systems

Goal of MaintenanceTo keep production systems in good working

order at minimal costIncrease availability of a systemKeep system’s equipment in working orderTo achieve product quality and customer

satisfaction through adjusted and serviced equipment

Maximize useful life of equipmentKeep equipment safe and prevent safety hazardsMinimize frequency and severity of interruptionsMaximize production capacity – through high

utilization of facility

Reactive(Breakdown or Corrective) MaintenanceReactive maintenance is basically the “run it till it

breaks” maintenance modedealing with breakdowns or problems when they occurNo actions or efforts are taken to maintain the

equipment as the designer originally intended to ensure design life is reached.

The referenced study breaks down the average maintenance program as follows: >55% Reactive 31% Preventive 12% Predictive 2% Other.

Advantages Vs DisadvantagesAdvantages

Low cost.Less staff.

Disadvantages Increased cost due to unplanned downtime of

equipment. Increased labor cost, especially if overtime is needed. Cost involved with repair or replacement of equipment. Possible secondary equipment or process damage from

equipment failure. Inefficient use of staff resources.

Preventive (Proactive) Maintenancecan be defined as follows: Actions performed on a time- or

machine-run-based schedule that detect, preclude, or mitigate degradation of a component or system with the aim of sustaining or extending its useful life through controlling degradation to an acceptable level.

Principle “Prevention is better than cure”reducing breakdowns through a program of

lubrication, adjustment, cleaning, inspection, and replacement of worn parts

The U.S. Navy pioneered preventive maintenance as a means to increase the reliability of their vessels.

Advantages Vs DisadvantagesAdvantages

Cost effective in many capital intensive processes. Flexibility allows for the adjustment of maintenance

periodicity. Increased component life cycle. Energy savings. Reduced equipment or process failure. Estimated 12% to 18% cost savings over reactive

maintenance program.

Disadvantages Catastrophic failures still likely to occur. Labor intensive. Includes performance of unneeded maintenance. Potential for incidental damage to components in

conducting unneeded maintenance.

Reasons for the need of a PM systemIncreased Automation

Business loss due to production delays

Production of a higher quality product

Just-in-time manufacturing

Need for a more organized, planned environment

Predictive Maintenancecan be defined as follows: Measurements that

detect the onset of a degradation mechanism, thereby allowing causal stressors to be eliminated or controlled prior to any significant deterioration in the component physical state.

Results indicate current and future functional capability.

predictive maintenance differs from preventive maintenance by basing maintenance need on the actual condition of the machine rather than on some preset schedule.

Advantages Vs DisadvantagesAdvantages

Increased component operational life/availability. Allows for preemptive corrective actions. Decrease in equipment or process downtime. Decrease in costs for parts and labor. Better product quality. Improved worker and environmental safety. Improved worker moral. Energy savings. Estimated 8% to 12% cost savings over preventive

maintenance program.Disadvantages

Increased investment in diagnostic equipment. Increased investment in staff training. Savings potential not readily seen by management.

Reliability Centered Maintenance“a process used to determine the

maintenance requirements of any physical asset in its operating context.”

Advantages Vs DisadvantagesAdvantages

Can be the most efficient maintenance program. Lower costs by eliminating unnecessary

maintenance or overhauls. Minimize frequency of overhauls. Reduced probability of sudden equipment failures. Able to focus maintenance activities on critical

components. Increased component reliability. Incorporates root cause analysis.

Disadvantages Can have significant startup cost, training,

equipment, etc. Savings potential not readily seen by management.

Computerized PM systemenhance your ability to track scheduled PM

activities, costs, work orders, breakdown trends, and repair parts

Used if you have a large multi-shift or multi-locationOperationTracking PM activities, inventory costs, and project

work orders, among other things is becoming more easier

Choose computerized PM program or computerized maintenance management system (CMMS) decision According to your needs.

most effective PM programs start out on paper.

MAINTENANCE AND EMPLOYING TOTALPRODUCTIVE WORK A successful and effective maintenance operation has to

break away from the ‘‘fix it when it breaks’’ mentality. The success of the maintenance operation must be

measured in uptime and not how many breakdowns get repaired. Finally, PM instructions (PMs) or repairs should be made before equipment breaks down.

This philosophy has the added advantage of allowing you to schedule the work rather than letting the work schedule you.

Employ the concept of total productive work (TPW) schedule your maintenance activities to maximize the productivity of your crew.

As you begin scheduling your crew’s time, they will realize it’s not business as usual. Be aware of potential negative perceptions of this new culture and work with your crew to help them

Implementation of PM ProgramSeven basic steps to professional maintenance

management1. Establish scheduling.2. Break down the facilities into logical parts.3. Develop an equipment list and assign equipmentnumbers.4. Develop and issue preventive maintenance (PM)instructions.5. Locate and/or develop equipment manuals.6. Develop a managed inventory.7. Monitor the program’s effectiveness and makeimprovements.

1) Establish schedulingplan out the daily activities of the

maintenance staff.The scheduling process will allow you to take

control of daily activitiesalso gives you a means to begin scheduling

the activities required to set up a PM program

scheduling can be the toughest, but it is the most critical.

Without successful scheduling you cannot hope to meet all your maintenance commitments

2)Break down the facilities into logical parts.Breaking up the plant sets the stage for

record-keeping activities and creates a framework for scheduling the PM work order instruction writing process

Use the facility’s physical structure, production processes, product lines, and cost centers to define what is ‘‘logical’’ for your program

make the structure meaningful to you and your staff.

Develop a simple easy-to-follow breakdown that everyone can understand and use.

3)Develop an equipment list and assign equipment numbersWe identify and number all the pieces of

equipment in the facilityThis list will serve as the structure for tracking

equipment maintenance activities.you will need to develop a numbering system for

the orderly assignment of equipment numbers.You will accomplish this step by issuing

workorders to gather data (e.g., S/N, model, size, manufacturer, age) on each piece of equipment in the newly mapped areas.

Don’t overcomplicate the numbering system.The numbers are meant to track workorder

transactions

4)Develop and issue preventive maintenance (PM) instructionsdevelop PM work order instructions for all the

pieces of equipmentThe PM work orders should include all necessary

activities for each interval (e.g., weekly, monthly, quarterly).

Existing equipment manuals and the writer’s individual experience will serve as the source of information for these initial PMs

After you writing the work instructions you need to send them out for a trial run, You will find out about their appropriateness, completeness, and usefulness after issuing the PMs several times

Use this feedback to help improve your program.

5)Locate and/or develop equipment manualsThis step develops the troubleshooting

information that rounds out the successful maintenance organization

Most maintenance shops have ‘‘manuals,’’A good manual addresses operating

procedures, troubleshooting guides, schematics, PLC programs (if applicable), parts lists, and other items (such as manuals for specific process control equipment).

6)Develop a managed inventorycreating a managed inventory that contains the

parts necessary to minimize downtime without duplicating the national debt.

A managed inventory will track the ins and outs of repair parts and generate reorder reports.

system also allow to track repair history and cost.You will need a plan for where to put parts, how

to store parts, what parts to remove, what parts to add, and how to maintain the inventory.

it pays to get your vendors involved in planning, organizing, and setting up of the inventory.

7)Monitor the program’s effectiveness and make improvementsPM program and the inventory won’t run by

themselves, Your success depends on continued commitment and management

you will need to modify items that do not work or were overlooked

lack of long-term commitment also impedes the success of even the most simple work order programs.