prev-maintenance-.pptx
TRANSCRIPT
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Preventive Maintenance
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OBJECTIVES
Explain the importance of maintenance in production systems.
Describe the range of maintenance activities.
Discuss preventive maintenance and the key issues associated with it.
Discuss breakdown maintenance and the key issues associated with it.
State how the Pareto phenomenon pertains to maintenance discussions.
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DEFINITION
WHAT IS MEANT BY THE TERM “MAINTENANCE” ?
Maintenance encompasses all those activities that maintain facilities & equipment in good working order so that a system can perform as intended.
Maintenance can also be termed as asset management system which keeps them in optimum operating condition.
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APPROACH TO MAINTENANCE.
Maint.
Planned
Unplanned
PM
BM
CM
TBM
CBM
Daily ChecksPeriodic ChecksPeriodic InspectPeriodic Service
PM: Preventive MaintenanceTBM: Time Based MaintenanceCBM: Condition Based Maint.BM: Breakdown maintenanceCM: Corrective Maintenance
Visual
Instrument
NOTE:- Structured recording of all the activities is vital.
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GOAL OF MAINTENANCE
The goal of maintenance is to keep the production system in good working order at minimal cost.
Decision makers have 2 basic options with respect to maintenance. They are: -BREAKDOWN MAINTENANCE.PREVENTIVE MAINTENANCE.
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TYPES OF MAINTENANCE
BREAKDOWN MAINTAINANCE:- Real approach, Dealing with breakdowns or problems
when they occur… PREVENTIVE MAINTENANCE:-
Proactive approach; Reducing breakdowns through a
program of lubrication, adjustment, cleaning, inspection, and replacement of worn parts.
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The best approach is to seek a balance between preventive maintenance and breakdown maintenance. The same concept applies to maintaining production systems.
The age and condition of facilities and equipment, the degree of technology involved,
The type of production process,
The decision of how much preventive maintenance is desirable.
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PREVENTIVE MAINTENANCE
More and more organizations are taking a cue from the Japanese and transferring routine maintenance (e.g., cleaning, adjusting, inspecting) to the users of equipment, in an effort to give them a sense of responsibility and awareness of the equipment they use & cut down the abuse & misuse of the equipment.
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PREVENTIVE MAINTENANCE
Preventive maintenance extends back to the design and selection stage of equipment and facilities.
Poor design can cause equipment to wear out at an early age or experience a much higher than expected breakdown rate.
Durability and ease of maintenance can have long term implications for preventive maintenance programs.
Training employees in proper operating procedures and in how to keep equipment in good operating order – and providing the incentive to do so – are also important.
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PREVENTIVE MAINTENANCE
The goal of preventive maintenance Preventive maintenance is periodic. Preventive maintenance is generally
scheduled using some of the following contributions:- The result of planned inspections that
reveal a need for maintenance. According to the calendar (passage of
Time). After a predetermined no. of operating
hours.
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PREDICTIVE MAINTENANCE
PREDICTIVE MAINTENANCE This is an attempt to determine
when best to perform preventive maintenance.
The better the predictions of failures are, the more effective preventive maintenance will be.
Preventive Maintenance
Preventative Maintenance
• What is a Preventive Maintenance?
– Preventive Maintenance is planned maintenance that is designed to improve Equipment life and avoid breakdowns on the plant.
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Preventive Maintenance: Basics
Basics
Task list
Single cycle plan
Strategy plan
Maintenance plan scheduling
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Time-based Performance-based Condition-based
Preventivemaintenance
Temperature
Thickness
PressurePressure
10102020
3030 4040 50506060
70708080
Pressure
2000
Types of Preventive Maintenance
Preventive Maintenance
• An Equipment can require maintenance activities to be performed based upon either time or a certain condition being met.
External visual inspection
1 month4Wks
Internal visual inspection
12 Wks
Check gear teeth for wear
52wks
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Preventive Maintenance: Phases and Roles
Maintenancetechnician
Maintenanceorder
Process maintenance orders4
Maintenanceplanner
Maintenanceplanner
Maintenancesupervisor
MaintenanceplannerTask list
Maintenanceplan
Schedule
Technicalcompletion
Create maintenance plans
Schedule maintenance plans
Technically completemaintenance orders5
2
3
1 Create task lists for differentobjects
Phase Contents Roles
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Preventive Maintenance: Task List
Basics
Task list
Single cycle plan
Strategy plan
Maintenance plan scheduling
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What?
Why?
For preventive maintenance (maintenance and inspection)
For routine maintenance (planned repairs)
For preventive maintenance (maintenance and inspection)
For routine maintenance (planned repairs)
Operations
Maintenance work centers
Material components
Production resources/tools
Maintenance packages
Task List
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Task list header
Operation 10Operation 20Operation 30
Planner group
Maintenancestrategy
3 months
3 months6 months
6 months12 months
12 months
Work center
Production resources/tools
Components
Maintenance Task Lists: Structure
Maintenance Strategy
• What is a Maintenance strategy?
– A Maintenance Strategy defines the frequency and scheduling data for Planned Maintenance activities.
Maintenance Strategy
4 Week 12 Weeks 24 Weeks
Time
Strategy
Package definition
2000
Scheduling parameters
What is a Maintenance Package?
Maintenance Package
3 months12
Weeks
Package number
Description
Cycle length
Unit of measurement
HierarchyOffset
• Maintenance packages define the frequency at which specific operations are executed. You can assign maintenance packages to the operations in a task list.
• Maintenance packages are part of a maintenance strategy.
12 Wks12 Wks
24 Wks
12 Wks
Strategy
12 wks12 wks
24 Wks
12 wks
Strategy
Same hierarchy levels
Different hierarchy levels
12 Wks
24 Wks
10
10
12 Wks
24 Wks
20
10 X
Maintenance Package Hierarchy
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Basics
Task list
Single cycle plan
Strategy plan
Maintenance plan scheduling
Preventive Maintenance: Single Cycle Plan
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I must perform thesame inspections atregular intervals.
1999
1997
Inspection of"Portable fire extinguishers"
every 2 years
94 96
98
2000
CHECKED
Single Cycle Plan: Business Process
Single Cycle Plan
• Simple and quick way to create a preventive or inspection plan.
• Includes only one cycle or frequency.• Can be either time or performance based.• All operations on the Task list will be
performed.• More than one Maintenance item can be
included.
What is a Maintenance Item -- ?
Maintenance Item• Every Maintenance plan will have at least one Maintenance item.• A Maintenance item can only belong to one maintenance plan.• The Maintenance item contains the following information:
– Description (Becomes the Maintenance order description)– Technical object– Task list– Planning Data
• Order or notification type• Planner group• Priority• Main work center• Maintenance activity type
– Object list
Maintenance Item (Cont.)
• A Maintenance item can contain more than one Technical object.• The Technical object can be an Equipment, Functional location or Assembly.• The Maintenance item description becomes the description of the Maintenance
notification or order.• For Maintenance items that are part of a Strategy based plan a Maintenance
strategy must be included within the item.• The Task list for this Maintenance item will also need to be linked to the same
Maintenance strategy.
Single Cycle Plan Steps
• Three steps in creating a single cycle plan.
Task List
Task List GroupPRTsComponents
Maintenance Item
Technical ObjectTask ListPlanning Data Maintenance Plan
Maintenance ItemScheduling Param.Cycle (Frequency)
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Scheduling Data and Maintenance Item
Responsibilities/Planning data
Referenceobject
Task list(optional)
3 months
Interval (cycle)
Maintenance item
Maintenance plan
Scheduling data
Maintenance item
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Using a Task List to Include an Operation List
Maintenance plan
Scheduling data
Maintenance item0010 Switch off
0020 Safety check
0030 External visual check
0040 Change seal
0050 Exchange H9 casing
0060 Check Z7 wire
Task list
Single Cycle Scheduling
Cycle Start
15.06.2004
15.03.2004
Cycle12 Weeks
Maintenance plan
Scheduling data
Maintenance item
Planned Date
15.09.2004
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Preventive Maintenance: Strategy Plan
Basics
Task list
Single cycle plan
Strategy plan
Maintenance plan scheduling
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Which parts must bemaintained at whichintervals?
External visual inspection
1 month1 month
Internal visual inspection
3 months3 months
Check gear teeth for wear
1 year1 year
Strategy Plan: Business Process
Maintenance Plan Steps
Task List
Task List GroupMaint. PackagesMaint. Strategy
Maintenance Item
Maint. StrategyTechnical ObjectTask List
Maintenance Plan
Maint. StrategyMaintenance ItemScheduling Param.
Strategy
Maintenance Packages
The Task List checks the Package to ensure the Strategy still exists.
The Item checks the Task List to make ensure that the same Strategy is used
The Plan checks the Item to make ensure that the same Strategy is used
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Task List and Maintenance Strategy
6 months6 months
3 months3 months
3 months3 months
6 months
3 months
Strategy
0010 Switch off
0020 Safety check
0030 External visual check
0040 Change seal
0050 Exchange H9 casing
0060 Check Z7 wire
Task list
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Creating a Time-Based Strategy Plan
3 months3 months
6 months
3 months
Strategy
0010 Switch off
0020 Safety check
0030 External visual check
0040 Change seal
0050 Exchange H9 casing
0060 Check Z7 wire
Task list
3 months3 months6 months
6 months
Maintenance plan
Scheduling data
Maintenance item
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Preventive Maintenance: Maintenance Plan Scheduling
Basics
Task list
Single cycle plan
Strategy plan
Maintenance plan scheduling
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ManualManualcallcall
NewNewstartstart
Start inStart incurrentcurrentcyclecycle
ScheduleSchedule
Last actual dateLast maintenancepackage
Last actual date
Nextplanned dateNext maintenancepackage
Cycle start
*
* Only for strategy plan
Schedule Maintenance Plans
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Cycle Start and Planned Date
Planned date
Order exactlyon planned date?
Cycle3 months
Cycle start
14.04. 2000
15.01.2000
Order 901760Maintenance plan
Scheduling data
Maintenance item
1
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Maintenance item report, sorted by equipment (no.)
1998 1999
Maintenance Scheduling Overview
... or as a listWith display variantsWith general list viewer
... as a graphicWith maintenance plan simulationWith/without details
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Predictive Maintenance
Predictive Maintenance is one of the four tactical options available to ensure the reliability of any asset to ensure it fulfils its function and it focuses primarily on maintaining equipment based on its known condition. Each of these strategies: on-failure, fixed time, predictive and design out, has a place in an optimized maintenance plan, the distribution of the mix being dependent on many factors.
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Predictive Maintenance
Predictive maintenance is often the most attractive concept, since action is only undertaken when knowledge of the asset indicates that failure or underperformance is imminent, making it a cost effective asset management option.
Many other benefits, some intangible such as the increased motivation of the workforce through increased competency, exist. Others include:
Equipment may be shut down before severe damage occurs or can be run to failure if required.
Production can be modified to extend the asset's life i.e. until the next planned shutdown.
Required maintenance work can be planned
All of the above lead to increased safety, plant output and availability and lead to improvements in final product quality.
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Predictive maintenance is a process that requires clear roles and responsibilities. As such we develop company appropriate predictive maintenance processes, supported by definitions of responsibilities, and communication paths, which integrate into the Reliability effort as a whole.
Condition monitoring facilitates Predictive Maintenance.
Condition monitoring is a knowledge-based activity, so for it to be successful and sustainable, it requires comprehensive skills training. Any successful predictive maintenance program, not only has a technology element, but requires a measurement system that continuously accounts for the benefits.
Predictive Maintenance
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Asset Performance Troubleshooting
Often it is a couple of poor performing assets with a chronic repeated failure condition that absorb the majority of the maintenance budget. Some commentators state that approximately 80% of a typical maintenance budget is stored away for chronic failures, making these the most cost depletive of all maintenance expenditures.
The following methodologies are key in any multi-technology condition monitoring program :
Root Cause Failure Analysis
Tribology And Lubrication Engineering Services
Specialist Condition Monitoring Services
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ROOT CAUSE FAILURE ANALYSIS
Root Cause Failure Analysis (RCFA) is both a process and a set of technical skills, which in combination find out why a particular failure or problem exists and sets in place a set of defense actions correcting those causes.
Typically, when assets fail most organizations have always found some understanding and rational leading to an explanation as to why it broke. But root cause failure analysis takes you beyond that to the latent roots, which are the management system weaknesses. Once you've found these, you have the means to solve many other potential problems that haven't yet occurred.
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Tribology And Lubrication
Tribology is the study of wear and lubrication.Tribology as it is estimated that component wear and lubrication problems are responsible for at least 70 % of mechanical failures.
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Tribology And Lubrication
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Condition Monitoring
In industry, condition monitoring is the measurement of parameters which may indicate a fault condition either by an increase or decrease in overall measured value or by some other change to a characteristic value.
When used as part of a pro-active maintenance plan, the use of condition monitoring enables the operation of a predictive maintenance policy and provides major improvements in productivity.
Condition monitoring depends on selecting the right mix of parameters that match expected faults and using the correct measurement technique, location interval and processing, it is also important to record enough information in order to be able to carry out monitoring and diagnosis.
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Condition Monitoring
Considerations include: • Type of measurement
• Measurement interval
• Accuracy of measurement
• Repeatability Condition monitoring falls into two distinct classes: Monitoring which can be carried out without interruption to
the operation of the machine
Monitoring which requires the shutdown of the unit, or at least the releases of the machine from its prime duty
The range of methods in use is very wide, from simple techniques such as visual surface inspections to more complicated procedures like spectral vibration analysis.
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PREVENTIVE MAINTENANCE
TOTAL PREVENTIVE MAINTENANCE JIT approach where workers perform
preventive maintenance on the machines they operate.
This approach is consistent with JIT systems and lean production, where employees are give greater responsibility for quality, productivity and the general functioning of the system.
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The TPM Concept
Develop a Company-wide philosophy to maximize the effectiveness of production systems.
Build an organization that prevents every type of loss zero accidents zero defects zero failures
Involve all departments in TPM implementation.
Involve everyone from top management to shop-floor operators
Use small groups (teams) to make improvements.
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The “Total” in TPM
Total effectiveness: pursuit of economic efficiency and profitability
Total PM: establishing a maintenance plan for the life of
the equipment - preventative maintenance - improved maintainability
Total Participation: autonomous maintenance by operators and
team based approach to problem solving
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Before TPM Implementation
Maintenance OperationsEngineering
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After TPM Implementation
WasteDowntime
Defects
The Common Enemies
A Team EffortOperations + Engineering + Maintenance
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Before TPM Implementation: Barriers
Operations
Maintenance
Engineering
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TPM Builds Bridges
Operations
Maintenance
Engineering
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The TPM Prerequisite
Only by adopting a proactive approachand putting in the time, effort, and resources
required can TPM be profitable for anOrganization
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A Model for TPM Development
Formal TPM Announcement
TPM Awareness Education
Form TPM Steering Group
Establish TPM Goals
Prepare Implementation Plan
Phase I
Preparation
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The TPM Development Model Continued
Conduct Focused Improvement Activities
Establish an Autonomous Maintenance Program
Implement a Planned Maintenance Program
Conduct Operation and Maintenance Skill Training
Build an Effective Administrative Support System
Phase II
Implementation
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Core TPM Activities Focused Improvement Projects Autonomous Maintenance Planned (Preventive) Maintenance Education and Training Early Management (Equipment Design and
Installation) Quality Maintenance Administrative and Support Activities Safety and Environmental Management Diagnostic and Predictive Maintenance
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The Major Plant Losses
Equipment Failures Process and Equipment Set-ups And
Adjustments Idling and minor stoppages Reduced Processing Speed Quality Defects Reduced Yield
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Ultimate Improvement Goals for Chronic Losses
Type of Loss Goal Explanation1. Equipment Failures 0 Reduce to zero for all equipment
2. Setup and Adjustments minimize Continuous effort to reduce setup times
3. Idling and minor stops 0 Reduce to zero for all equipment
4. Reduced ProcessingSpeed
0 Bring operating speed to design speed;then improve speed beyond design level
5. Quality Defects 0 Small levels might be acceptable (6-sigma)
6. Yield Losses minimize
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Measurement
Measurement Is Necessary for Improvement.
People Do How They Are Measured!
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Basic TPM Outcome Measures
Productivity
Units per labor hourValue added per person
Throughput Downtime
Number of Breakdowns
Quality
Product DefectsWarranty Costs
Customer Satis. Index Re-worked units
Scrap/Waste
Costs
Labor CostsMaintenance Costs
Energy Costs
Delivery
On-time shipments
Safety
Lost time AccidentsIncidents
Near Misses
Employee Satisfaction
Number of Improvement IdeasNumber of Teams
Employee Satisfaction Index
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Measuring Effectiveness
Overall Equipment Effectiveness --
OEE
OEE = Availability x Performance Rate x Quality Rate
OEE: A Measure of the Percentage of Time that the Equipmentis Adding Value
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Calculating OEE
OEE = A x P x Qwhere:
A (Availability) = planned time - downtimeplanned time
P (Performance rate) = (standard time/unit)(units produced) Operating time
Operating Time = (planned time - downtime)
Q (quality rate) = (total production) - (number of defectives)total production
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OEE Example
The Plant operates 1,440 minutes per day (3 shifts) Downtime averages 120 minutes per day. Daily production averages 900 units with a 20 % defect rate. The standard time per unit is .8
minutes. (Assume that A, P, and Q are equally weighted.)
Compute OEE
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Computing OEEWeightings on A, P, and Q
In many instances Availability, Performance rate and Quality rate arenot considered to be equal in importance. Instead they are weighteddifferently. For example:
kA = .3 kP = .2 kQ = .5
OEE = A.3 x P.2 x Q.5
Compute OEE using these weights.
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OEE Component Targets
Availability (A) > .90 Performance Rate (P) > .95 Quality Rate (Q) > .99
Availability (A) > .90 kA
Performance Rate (P) > .95 kP
Quality Rate (Q) > .99 kQ
unweighted targets
weighted targets
}}
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OEE ExamplesSource: Japan Institute of Planned
Maintenance
Criteria AutomatedMachinery
AutomaticAssemblers
AutomaticPackers
1. Overall Effectivess
2. Availability
3. Performance
4. Operating Speed Rate
5. Net Operating Rate
51.3 - 78.4
95-98
54-80
90-100
60-80
38.0 - 80.7
95
40-85
100
40-85
72.0
90
80
100
80
Remarks: 20-40% of lossesdue to idling andminor stoppages
15-60% oflosses due to
idling and minorstoppages
20% of lossesdue to idling andminor stoppages
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Overall Equipment Effectiveness-- OEE
OEE Is OEE Is Not
• A Measure of TPM Progress
• Manufacturing Contribution to Quality Improvement
• A Method to Identify Opportunities for Improvement
• Synonymous with TPM
• To be used to compare facilities
• The same as utilization
• Easy to calculate
MB 533 Shannon/Fry October, 200074
Chronic and Sporadic Losses
Chronic Losses: Losses that occur repeatedly within some range of distribution
Sporadic Losses: Sudden occurrences that go beyond the normal range
Sporadic Loss
Chronic Loss
Defect rate
Time
OptimalCondition
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Chronic and Sporadic Losses
Sporadic Losses Chronic Losses
Latency
Causation
Types ofAction
EconomicImpact
Conspicuous Hidden
Cause-and-effect Often unclear - rarelyeasy to determine a single cause
Direct Fixes can May take many triesbe made
Can be very costly Cumulative effect cancan be very costly
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How Chronic Losses are Reduced
Increasing Equipment Reliability
Restoring Equipment to its Original Condition
Identify and Establish Optimal Operating Conditions
Eliminating Small Defects that are Often Overlooked
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Reliability Issues
Intrinsic Reliability Operational Reliability
Design Reliability
Manufacturing Reliability
Installation Reliability
Operation Reliability
Maintenance Reliability
Based on Equipment Design Based on Use (conditions)
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Learning to Use Equipment Fully and Make Basic Improvement
Study ofEquipment
Usage
Techniquesfor Making Useof Equipment
Techniquesfor Managing
Equipment
Restoration
Search forOptimal Conditions
Eliminate MinorEquipment Defects
Physical AnalysisP-M Analysis
Eliminate TamperingTrial-and-Error
Gather Operators’Experiences
Design Reliability
FabricationReliability
InstallationReliability
OperationReliability
MaintenanceReliability
Intr
insi
cR
elia
bil
ity
Op
erat
ion
alR
elia
bil
ity
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P-M AnalysisP Phenomena- physical-problem—M machinery-manpower-material
All pertinent factors in a chronic loss are efficientlyidentified and eliminated.
Clarify the Problem
Conduct a PhysicalAnalysis of the
Problem
List Every ConditionPotentially Related
to the Problem
Evaluate Equipment,Materials, and
Methods
Plan the Investigation
InvestigateMalfunctions
FormulateImprovement
Plans
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Raising Employee Skills Through TPMA TPM Goal is to Improve Employee Skill
Levels
Attention concentration, discernment
Judgment logical thinking, make sound decisions
Take Correct Action and provide Appropriate Treatment Prompt action, pride of ownership
Preventative understanding of equipment, measurement
Prediction Skills subtle signs, knowledge of equipment
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Focused Improvement
Focused Improvement is an active priorityof any TPM program - It begins simultaneously
with the start of TPM
“Focused Improvement includes all activities that maximize the overall
effectiveness of equipment, processes, and plants throughuncompromising elimination of losses and improvement of
performance.”
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Focused Improvement
Select a Project
Form a Project Team
Register the Project
Follow the P-M AnalysisCycle
A High PriorityDoableShort-term
4-7 peopleCross-functionalEmpowered
Establish StatusAccess to ResourcesCommitment ongoing training and
educationMeasure Progress and results
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Preparation by Improvement TeamsTeams should prepare in the
following ways.
• Understand the philosophy of focused improvement• Understand the significance of losses and the rationale of
improving overall effectiveness• Understand the production process well• Gather data on failures, trouble, and losses and plot
over time• Clarify the basic conditions necessary to assure proper
functioningof equipment and define what factors contribute to its optimalstate• Understand the necessary techniques for analyzing and
reducingfailures and losses
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Focused ImprovementStep-by-Step Procedure
Activity/Step Detailed Outline
Step 0: Select the Project Select and Register the ProjectForm the Project TeamPlan Activities
Step 1: Understand Situation Identify bottleneck processesMeasure failures, defects, and other
lossesUse baseline to set targets
Step 2: Expose and Eliminate Carefully Expose all Abnormalities Abnormalities Restore deterioration and correct
minor flawsEstablish basic equipment conditions
Step 3: Analyze Causes Stratify and Analyze CausesApply analytical techniques (P-M Analysis)Conduct experiments
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Focused ImprovementStep-by-Step Procedure (continued)
Activity/Step Detailed Outline
Step 4: Plan Improvement Draft Improvement ProposalsCompare cost-effectiveness of alternative proposalsList disadvantages of each alternative
Step 5: Implement Improvement Carry out improvement plan
Provide instruction related to implemented changes
Step 6: Check Results Evaluate improvement over time and the project proceedsCheck whether targets have been achievedIf not, go to step 3 and continue
Step 7: Consolidate Gains Draw up control standards to sustain resultsFormulate work standardsFeed information back into themaintenance prevention program
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Analytical Techniques for Improvement
P-M Analysis Ask Why 5 times Fault tree Analysis (FTA) Failure Mode and Effect Analysis Industrial Engineering Value Analysis Seven Basic Tools of Quality The “New Seven” Tools of Quality
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Autonomous MaintenanceMaintenance Performed By the Equipment
Operators
One of the most important basic buildingblocks in any TPM Program
Goals of Autonomous Maintenance:• Prevent equipment deterioration through
correct operation and daily checks• Bring equipment to its ideal state through
restoration and proper management• Establish the basic conditions needed to keep
equipment well-maintained
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Autonomous MaintenanceStep-by-Step Implementation
Activity/Step Detailed Outline
Step 1: Perform Initial Cleaning Eliminate Dust, Dirt, and Grime Expose any irregularities Correct minor flaws
Step 2: Eliminate Sources of Contamination Reduce housekeeping by eliminating sources of dirt . Improve access to difficult areas
Step 3: Establish cleaning and checking Formulate standards for cleaning, standards lubricating, and tightening with minimal
time and effort. Improve efficiency of checking gauges and visual display controls
Step 4: Conduct General Equipment Provide inspection skills training Inspections Modify equipment to facilitate inspection
Chart inspection results - quantify when Possible.
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Autonomous MaintenanceStep-by-Step Implementation (continued)
Activity/Step Detailed Outline
Step 5: Perform General Process Train and Educate Operators to Inspections achieve process-competent operators
Prevent inspection duplications and omissions by incorporating individual equipment inspection standards into
process or area inspection plans.
Step 6: Do Systematic Autonomous Establish clear procedures for auto- Maintenance nomous maintenance
Reduce Setup ProceduresEstablish system for self-management
for spares, tools, data, etc.
Step 7: Practice Full Self-Management Keep accurate maintenance recordsPerform proper data analysisTake appropriate action
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Necessary Accomplishments forProcess-Competent Operators
Level 1: Understand Process Performance and
Function Operates Process Correctly
Level 2: Understands the properties of the materials
handled Performs correct adjustment and settings
Level 3: Detects abnormalities promptly Takes emergency action against abnormalities
Level 4: Recognizes sign of abnormality Deal with abnormalities correctly Performs periodic overhaul checking and parts
replacement
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Keys to Successful Autonomous Maintenance
Introductory Education and Training TPM Objectives, TPM Benefits, TPM Overview
Cooperation Between Departments and Shifts Consensus agreement on how to support TPM
and AM Group Activities
small groups with leadership from shop floor to management
AM is not voluntary mandatory and necessary management must provide leadership and
support
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Keys to Successful AM (continued)
Practice practical application versus conceptual understanding
Progressive Education and Training gradual skill development - step-by-step - as needed
Aim for Measurable Results clear, appropriate measures (and goals)
Operators Should Determine Standards to Follow operators set standards and criteria for maintenance
consistent with organizational objectives Management Should Audit the AM Progress
provide guidance, support and critique
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Keys to Successful AM (continued)
Use Model Projects Use as examples for the rest of the
organization Correct Equipment Problems Promptly
Maintenance department must react quickly to fix problems uncovered by AM activities - will require commitment and appropriate staffing
Take Time to Perfect AM Don’t rush the process - make sure the
skills are there
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Measures of Preventive Maintenance Results
Downtime Trend Operating Rate Failure Frequency Failure Severity (length of failure downtime) Maintenance Time per Incident Quality Defect Rate Failure Costs Emergency Repair Time Ratio of Maintenance Cost to Unit
Production Cost
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IMPLEMENTATION SUMMARY OF PM
Step 1: Evaluate Equipment and Understand Current Conditions.
Step 2: Restore Deterioration and Correct Weaknesses.
Step 3: Build an Appropriate Information System.
Step 4: Build a Periodic Maintenance System Step 5: Build a Predictive Maintenance
System. Step 6: Evaluate the Preventive Maintenance
System.
Like everything associated with TPM, successful implementation of apreventive maintenance system will take time and support.
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BREAKDOWN MAINTENANCE
The risk of a breakdown can be greatly reduced by an effective preventive maintenance program.
The major approaches used to deal with breakdowns are:- Standby or backup equipment can be quickly
pressed into service. Inventories of spare parts. Operators who are able to perform at least
minor repairs on their equipment. Repair people who are well trained and readily
available to diagnose and correct problems with equipment.
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BREAKDOWN MAINTENANCE
Breakdown programs are most effective when they take into account the degree of importance a piece of equipment has in the production system
The ability of the system to do without it for a period of time.
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Review of Equipment Maintenance
The Review of Equipment Maintenance (REM) is an incremental approach, designed to deliver financially driven results at minimum cost and time. It provides optimum results when a review of equipment maintenance is required to ensure that:
The most effective maintenance plan is adopted
Preventive, scheduled, design put and on-failure maintenance are integrated into a cohesive strategy
The maintenance plan needs to respond to changes in plant operation
The review may also be required to introduce a new technique, such as condition monitoring, or to adjust changes in maintenance resources. Typically REM requires only 30-50% of the resource input that would be required for RCM, while achieving similar results.
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Review of Equipment Maintenance
REM focuses primarily on maintenance strategy arising from business drivers, such as demand and operating patterns and can be considered in two major stages:
Reliability and criticality analysis
Maintenance review
100
The output of a REM study is an optimized maintenance plan, where the appropriate risk based defence of the asset is defined. This takes in
to account the goals of the organisation, the criticality of the
asset, the resources available, and the level of technology employed by the organization. This is a working document, which can be translated
into the physical reality of conducting operational maintenance.
Review of Equipment Maintenance
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PARETO DIAGRAMS
Pareto diagram is an important quality tool used in prioritizing & deciding the course of action in maintenance management.
Of all the problems that occur, only a few are quite frequent/costly.
The others seldom occur/cost less. The problems are grouped and
labeled as vital few and trivial many.
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PARETO DIAGRAMS
Pareto principle lends support to the 80/20 rule.
Pareto diagrams help quickly identify the critical areas for management’s attention.
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STEPS FOR CONSTRUCTING PARETO DIAGRAMS
STEP 1Decide on data categorization system by problem type, type of conformity (critical, major, minor) or whatever else seems appropriate.
STEP 2 Determine how relative importance is to be judged i.e., whether it should be based on cost or frequency of occurrence.
STEP 3 Rank the categories from most important to least important.
STEP 4 Compute the cumulative frequency of the data categories
in their chosen order. STEP 5
Plot a bar graph showing the relative problem of each problem area in descending order.
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STEP 6
Identify the vital few that deserve immediate attention.
STEPS FOR CONSTRUCTING PARETO DIAGRAMS
105
PARETO DIAGRAMS
PROBLEM TYPE
DESCRIPTION % OF OCCURENCE
ANNUAL COST (IN
$1000)
CUMMALITIVE % OF
OCCURENCE
A Substandard quality of raw material
40 20 40
B Improper setting of machine
20 6 60
C Inadequate operator training
14 3 74
D Poor storage of finished parts
10 2 84
E Drop in hydraulic pressure impresses
8 2 92
F Cutter not sharp 5 1.5 97
G Electrical breakdowns 3 1.8 100
106
PARETO DIAGRAMS
A B C D E F GPROBLEM TYPE
% OF
TOTAL
100
80
60
40
20
0
40.0
60.0
74.0
84.0
92.097.0
100.0
MAINTENANCEMANAGEMENT
SYSTEM
ContentIntroductionIntroduction to Life Cycle CostObjectives of Maintenance and Maintenance CostMaintenance DefinitionHow to get unplanned repair jobs plannedMaintenance ProceduresFailure DevelopmentTotal Productivity MaintenanceMaintenance Management Systems
IntroductionModern maintenance management is not to repair broken equipment rapidly. Modern maintenance management is to keep the equipment running at high capacity and produce quality products at lowest cost possible.
Introduction contd…Maintenance, then and nowMany years ago, the manufacturing and production work was
done with relatively simple technical equipment and the involvement of more manpower.
Maintenance was of course simple and impact to certain extent to the function of machines.
During the industrialization, production equipment has been more developed. In connection with the high technical development the impact of productivity and quality has moved from man to machine.
The importance of maintenance has considerably increased.
Introduction contd…There are many reasons why maintenance is becoming more and
more important. In developing countries , where many old machines are operating, the spare part problem are arising. Some times it is difficult to find spare parts for equipment and if it is possible to find them, they are usually very expensive and must be paid on foreign currency.
Due to long lead times of supply of spares, it is common that the spare part inventory is growing bigger than necessary. A very essential part in maintenance management is developing countries to reduce the need of spare parts, as well as to maintain the minimum level of shock to save foreign currency, but still keeping the productivity high.
Introduction to Life Cycle Cost(LCC)
Maintenance has to be taken into consideration in very early stage of work of procuring new equipment to ensure a good and cheap operation.High quality equipment will give high reliability and maintainability which secure high productivity and equipment efficiency.The lifetime of the equipment can be spilt up in six phases1. Idea2. Specification3. Design4. Procurement(Manufacturing)5. Operation6. Windup
LCC ContdBath Tub CurveThe bath tub curve describes the cost of equipment over its lifespan. From commissioning to winding up.
Cost
100% Life Time
LCC – What Dose It Stand For?
LCC – Life Cycle Cost – is commonly understood to be the customer’s total cost and other sacrifice during the actual life time of the product. Hence LCC includes the acquisition cost as well as all future costs for operation and support of the product until it is finally discard.
LCC Is Used For….
Comparison of alternative products.
Improvements of products.
Adaptation of the maintenance and support organization.
Objectives of Maintenance and Maintenance Cost
Objectives of MaintenanceDuring the years the maintenance function has not been seen as a condition for production output. The previous approach has been that maintenance is the necessary evil, one among the cost generators in the organization. Very often the maintenance strategy in plants has been to reduce the maintenance cost as much as possible without thinking of the consequences.Objective of the maintenance is , as priority one , to create an availability performance which is suitable for production demands in the organization. No mechanized/atomized company has yet succeeded to produce with stopped equipment. Production buy availability performance from maintenance.
Contd…1.
Keep up the planned availability performance
2.At the lowest cost
Above allWithin the safety prescriptions
Maintenance CostAll enterprises and organizations are interested in lowering maintenance costs. A very common delusion is that
THE PRODUCT GIVES THE INCOME
MAINTENANCE COSTS MONEY
Contd…MAINTENANCE WICH IS NOT CARRIED OUT ,WILL COST EVEN
MORE THAN MONEY !!!!!!
Contd…There are two ways of managing the maintenance costs
Cost or Result Controlled
Maintenance
Contd… The cost controlled maintenance is not considered as modern maintenance
management, The reason why maintenance has been treated as a cost controlled activity, Is often that engineers and technical staff have had some dilemma to measure the results of investments in maintenance in total economical terms. It is simple to find the direct cost for maintenance but it could be difficult to see the results.
The upper priority in the objectives of maintenance is to “keep up planned availability performance at the lowest cost possible” . This means that the long term results are important. The maintenance cost must be put in relationship with overall results achieved by maintenance in production facility.
PRODUCTION LOSSES
The Hidden Possibility
LOST MARKET
WORKENVIORME
NT
CAPACITYLOSSES
ENERGYLOSSES
QUALITYLOSSES
CAPITALCOSTS
INCREASED
INVESTMENT
MAINTENANCE
Indirect & Direct MaintenanceCosts
The maintenance cost can be split up in two different categories.
Direct maintenance costs -
Indirect maintenance costs -
The costs are directly related to the performance of the maintenance works
Losses due to maintenance
Contd…Direct maintenance costs• Wages & Salaries• Material Costs• Administration Costs• Costs for training• Spare parts costs• Contracted work forces• Modification Costs
Indirect Costs• Loss of revenue or other losses as a result of interruption
to production as a result of maintenance.
Measurement of Maintenance Efficiency
Many times there are needs to measure the maintenance efficiency. However, maintenance can not be measured by the cost it creates. There must be an connection to the production out put some way. It is naturally impossible to determine anything about the size of the direct costs. One method to control the direct maintenance is to use the PM-factor.”P” stands for prime product produce and “M” stands for maintenance cost. When using the PM-factor, the result of the maintenance impact on the production is measured. How many products are produced per a 1000 units of “maintenance money”.
PM – Factor = X Prime Production
Maintenance Cost
1000
Availability Performance& Productivity
AVAILABILITY PERFORMANCE
The ability of equipment to function properly,Despite occurrence of failures, disturbances and
Limitations in the maintenance resources.
Contd…
Availability performance can be divided in to tree parts:
Reliability Performance
Maintenance Support Performance
Maintainability Performance
Reliability Performance
The ability of an item, under statedConditions of use, to perform a requiredFunction under stated conditions for a
stated period of time.
Maintenance Support Performance
The ability of a maintenance organization,Under stated condition, to provide upon
Demand the resources required toMaintain an equipment.
Maintainability Performance
The ability of an equipment, under started conditions of use, To be retained or
restored to state in which it can perform a required function, when maintenance is performed under stated conditions and using stated procedure and resources.
Maintenance DefinitionIn order to set up maintenance strategy for an enterprise, it is necessary for every body in a company to understand the maintenance concept and speak the same language.
MAINTENANCE
The term maintenance covers allActivities undertaken to keep equipment in a
Particular condition or returnIt to such condition
Contd…The term maintenance consists of three main parts
Corrective maintenance
Preventive maintenance
Improvement maintenance
CORRECTIVE MAINTENANCE (CM)
Corrective maintenance covers allMaintenance which is carried out inOrder to correct (repair) a fault in
equipment
WHAT IS FALIURE ?
Digress of demands of a certainquality
Planned & unplanned corrective maintenanceCorrective maintenance is divided in
CORRECTIVEMAINTERANCE
UNPLANNED PLANNED
Break DownEmergency Repairs
UrgentNot possible to ControlYou are controlled by
the equipment
Planned MaintenancePrepared ProperlyPossible to Control
You control the Equipment
PREVENTIVE MAINTERANCE (PM)
Preventive maintenance covers allProgrammed maintenance which is carried out in order to prevent theOccurrence of failures before they
Develop to a breakdown orInterruption in production.
Preventive Maintenance is Divided In
INDIRECT
Condition BasedMaintenance (CBM)
Detection of failuresBefore break down
PREVENTIVE MAINTENANCE
Indirect Maintenance
Subjective
Using human sensesLook , feel , listen , smell
, taste
INDIRECT PM
IMPROVEMENT MAINTENANCE (IM)Improvement maintenance is used
When to modify the equipment so theCondition improves. Improvement
Maintenance includes activities which are carried out once. The objectives of
improvement maintenance are toDesign out the failure i.e. the failureWill never occur again or extend the
life time of parts.
How to Get Unplanned Repair Jobs Planned
One of the objectives of the maintenance job is to get them plannedThis gives increased availability performance and lower direct maintenance costs and a lot of other advantages. The load on the maintenance department will for instance be lower and the quality of the jobs higher.• Use of condition monitoring Through condition monitoring the failure development and it is therefore possible to plane the forthcoming jobs before a break down occurs. By condition monitoring the unplanned jobs are transferred to planned job.
• Planned maintenance resulting in lower costs for maintenance and lesser down time.
MAINTENANCE
CORRECTIVEMAINTENANCE
UNPLANNED
-EXPENCIVE MAINTENANCE
-LOW AVAILABILITY
PLANNED-
CONTROLLED
-REDUCED COST FOR
MAINTENANCE-INCREASEDAVAILABILITY
PREVENTIVE MAINTENANCE
INDIRECT CONDITION
MONITORING
DIRECT-CLEANING
-LUBRICATING-
PROGRAMMED
REPLACEMENT AND
REPAIRS
DECREASED-CORRECTIVE MAINTENANCE
INCREASED-AVAILABILITY
Preventive Maintenance-Reduce number of break downs & urgent repairs-More planning and control of corrective maintenance
Result-Increased availability performance & efficiency-Decreased cost of maintenance
Proper PlanningResults in the correct maintenance work is carried out
At the right time In the right way By the right professional With the right spare parts
“Real maintenance management is impossible without condition based preventive maintenance”
Maintenance ProceduresWhen a maintenance strategy is going to be formulated, there are many maintenance procedures that could be chosen, From sophisticated procedures to low level procedures.
Operate to break down (unplanned corrective maintenance), O.T.B.D
Fixed-time maintenance, F.T.MCondition-based maintenance, C.B.MDesign out maintenance, D.O.MLife-time extension, L.T.ERedundancy, RED
Failure Development INDIVIDUAL LIFE TIME
Machines, spare parts, all types of equipment, have their own individual lifetime. The individual life time is different from part to part and is influenced by the quality of the product but also by other outside factors such as environment, handling etc.Some failures are occurring after a certain, expected time, and can almost be predicted. Some failures are occurring completely unexpected.
FAILURES
RandomFailures
Regular Failures
Non-Predictable Predictable
Failure Developing time(FDT)Some failures either they are random or regular, have longer or shorter failure development time. The failure development time is the deterioration time from the moment condition departs from the normal condition until the moment of break down occurs.
Failures with failure development time is easier to handle than the failures without failure development time.
Shorter FDT – Continuous on line condition monitoring has to be applied
Longer FDT – Off-line condition monitoring has to be applied
Total Productivity MaintenanceTotal Productivity Maintenance (TPM)
TPM is a way of organizing maintenance to support productivity & quality through increased equipment efficiency and to reduce costs.
TPM concept means that all employees work in small groups to maximize the improvement of equipment efficiency.
Operators are working independently with all maintenance activities of their own equipment and have also the total responsibility of operation and maintenance.
Fundamental Goals of TPMIncreased productivity and qualityZero defectsReduced cost of maintenance and productionIncreased motivation among all employeesZero accidentShorter lead timeZero unplanned stopsDevelopment of staff through trainingImprovement of work environment
Incentives for MMS or CMMS (rule of thumb)
Reduction on MDT about 20%
Increased machine life about 20 %
Saving on labour and spares 10 – 20%
Savings on maintenance budget 10 – 20%
Maintenance Management Systems
General of maintenance systemsThe maintenance function must also have necessary aids to manage the maintenance activities to coop up to the main target of the enterprise. Maintenance management means a better control of the maintenance organization and the related area. To properly control the maintenance of a facility, information is required to analyze what is occurring.
To be able to manage the maintenance activities in the right way, a maintenance management system is necessary. The system can be either manual or computerized. The main purpose of a maintenance management system is in operation and works properly.
The Basic MaintenanceCycle
PLANNING
PERFORMANCE
RECORDING
ANALYSIS
The basic function of a maintenance management system can be :
1. Preventive maintenance2. Plant and unit record(Equipment)3. Inventory and spare parts control system,
Purchasing system4.Document record5.Planning system for maintenance and work order
routines6.Technical/economic analysis of plant history,
maintenance and machine availability