Introduction
• Reliability is about time to failure
• Maintenance is about restoring equipment and processes to operation
• Engineering is finding the right balance between cost and action
MAXIMIZING POTENTIAL BENEFITS OF MAINTENANCE ACTIVITIES
Session 2
Objectives
• Reduce operating cost while boosting productivity though equipment maintenance
• Analyzing equipment failures for proactive, predictive & preventative maintenance
• Selecting the appropriate maintenance approach
• Developing a maintenance program
Cost of Maintenance
• Spares• Labor• Training• Diagnostic Equipment
• It takes an investment
Cost of Downtime
• Loss production• Restart Costs• Loss of Revenue• Opportunity Costs
• Unscheduled downtime
Benefit of Operating
• Revenue• Production• Efficiency• Uptime
• Less downtime means More uptime and value
Discussion & Questions
Reliability
• Common Understanding
• Function• Environment/Use• Duration• Probability
Availability
• Common Understanding
• Inherent – ideal
• Achieved – PM & CM included
• Operational – actual with all downtime
Maintainability
• Two elements
• Design for maintainability
• Effectiveness of repairs– Good as new– Bad as old– Somewhere between
Uptime
• Operating when it should be operating
• Who defines and how is this defined?
Discussion & Questions
Equipment Failure
• Provides guide to maintenance approach
• What are the results of failure?
• What is known about failure modes and mechanisms?
Types of Failures
• A range
• Nobody cares
• Degradation
• Shut down
Failure Impact
• A range of impacts
• Nobody cares (why is the equipment here?)
• Degraded operation
• Major repair/restart
Failure Signs
• Is there a warning?
• Measured and predicted
• Slow degradation of throughput or quality
• Sudden and unforeseen
Discussion & Questions
Reactive
Consider for
• Small items• Non-critical• Inconsequential• Unlikely to fail• Redundant
Preventive
Consider if
• Subject to wear out• Consumable
replacement• Failure pattern known
Predictive
Consider when
• Random failure pattern• Not subject to wear• PM induce failures
Proactive
Consider with
• Root Cause Failure Analysis
• Age Exploration• FMEA
Discussion & Questions
Interval v. Conditional
Interval or time based
• Fixed schedule• Assumes wear or
predictable time to failure
• Easy to manage and plan
Condition based
• Focus on failure mechanisms
• Consider cost of failure• May require health
monitoring• Cost effective
How to decide an approach
Ask these questions:
• Nature of failures?• Able to detect ?• Predictable?• Indicators?• Cost of failure?• Cost of maintenance?
Approaches
• Reactive
• Preventive
• Predictive
• Proactive
Discussion & Questions
Get the data
• Data, Data, Data
• Convert to information
• Do the math
• Look for Stability and Exceptions
Where to start
• Use data you have to start – build case for better data collection
• Run experiments to get better data
• Next focus on high value areas
Build a program
• Maintenance procedures
• Tools and training
• Engineering– Design, Reliability &
Operations
• Connect to business
Metrics
• Not MTBF
• Business metrics– Revenue, throughput,
etc.
• Time to failure– Mean Cumulative
Function or Life Distributions
Discussion & Questions
Summary
• Value – do what adds value
• Understand failure mechanisms
• Time to failure & Environmental data
• Breadth of Maintenance Engineering
Maximize potential benefits of maintenance activities
