1. AVAILABILITY PERFORMANCE
THIS IS THE KEY TO
PRODUCTIVITY IMPROVEMENT
IT IS ESSENTIAL TO
STUDY THIS IF WE ARE TO
DO ANY IMPROVEMENT
TO MAINTENANCE

2. GENERALLY A MACHINE (OR A SYSTEM)
CONTINUES TO WORK (UP TIME) UNTIL IT
BREAKSDOWN.
ONCE A FAILURE OCCURS, IT IS REFERRED TO
A PERSON (OR A SYSTEM)
WHICH WILL PUT IT BACK TO OPERATION.
IT WILL TAKE SOME TIME
FOR THEM TO RESPOND (WAITING TIME)
AND WILL START ATTENDING TO IT.
AFTER THE ELAPSE OF THE
ACTUAL REPAIR TIME THE MACHINE WILL
BE BACK IN OPERATION.

3. THIS PROCESS WILL CONTINUE AND GO THROUGH
A NUMBER OF CYCLES DURING THE LIFE TIME OF
THE MACHINE.
FOR A GIVEN SYSTEM or a MACHINE
IT WILL BE POSSIBLE TO CALCULATE
MEAN WAITING TIME (MWT)
MEAN TIME TO REPAIR (MTTR)
MEAN TIME BEFORE FAILURE (MTBF)

4. FOR LONG BREAKDOWN PERIODS
RUNNING TIME OF ANY OPERATION
BREAKDOWN PERIODS
START
time
OPERATION PERIODS
WHAT ARE THE REASONS
FOR LONG BREAKDOWN PERIODS

5. A GOOD MAINTENANCE MANAGER
SHOULD BE ABLE TO
IDENTIFY REASONS
for any excessive
delays in breakdowns

6. SITUATION MORE CAREFULLY
LET US EXAMINE THIS
SITUATION MORE CAREFULLY
THIS COULD BE
EXAMINED BY IDETIFYING
MTBF
MWT
MTTR

7. DEFINITION 1
b b b b4
R R R R R5
OPERATION PERIODS
(R1+R2+R3+R )
(No. of Breakdowns)
MTBF =
MEAN TIME BEFORE FAILURE

8. MTBF : Mean Time Before Failure
can be split into
two components
Supplied Reliability Performance
&
User Dependent Reliability Performance
HENCE IT DEPENDS ON
RELIABILITY PERFORMANCE

9. Duration of actual repair
DEFINITION 2
BREAKDOWN PERIODS
b b b b4
b1, b2 … consists of two components
Waiting for the
actual repair to begin
AND
Duration of actual repair

10. Duration of actual repair
Waiting for the
actual repair to begin
THE AVARAGE OF THESE TIMES
IS THE MEAN WAITING TIME
MWT
Duration of actual repair
THE AVAERAGE OF THESE PERIODS
IS THE MEAN TIME TO REPAIR
MTTR

11. MAINTENANCE SUPPORT PERFORMANCE
MWT
THIS IS DEPENDENT ON
MAINTENANCE SUPPORT PERFORMANCE
MTTR
THIS IS DEPENDENT ON
MAINTENANABILITY

12. RELIABILITY PERFORMANCE (MTBF) DEPENDS ON THE FOLLOWING FACTORS
Design & construction
Installation
Overloading
Raw material quality
Environment
Skills and abilities of operators
Quality of maintenance work
Reliability performance of Maintenance
subsystems
CONTINUED

13. RELIABILITY PERFORMANCE (MTBF) DEPENDS ON THE FOLLOWING FACTORS
CONTINUED
Quality of spares
Preventive maintenance
Operating conditions
Interlocking systems
Quality of materials
Redundancy
Modifications
Age
Supporting services (Electricity & water)

14. MAINTENANCE SUPPORT PERFORMANCE DEPENDS ON THE FOLLOWING FACTORS
(MWT)
DEPENDS ON THE FOLLOWING FACTORS
Good organization
Good communication
Access to spares
Technical documentation
Access & simplicity
Skill and experience of people
Ease of trouble shooting
Cooperation between departments
Information systems
CONTINUED

15. MAINTENANCE SUPPORT PERFORMANCE DEPENDS ON THE FOLLOWING FACTORS
(MWT)
DEPENDS ON THE FOLLOWING FACTORS
CONTINUED
Workshop facilities
Right personal management
Handling of equipment
Planning
Spare-part management
Infrastructure
Work environment
Manpower availability
Proper tools

16. MAINTENABILITY PERFORMANCE (MTTR) DEPENDS ON THE FOLLOWING FACTORS
Design for accessibility
Complexity/simplicity
Location & layout
Use & supply of proper instruction manuals
(in time)
Work performance
Aids & facilities for maintenance
Accuracy & standardization of spares
Powering down systems
CONTINUED

17. MAINTENABILITY PERFORMANCE (MTTR) DEPENDS ON THE FOLLOWING FACTORS
CONTINUED
Safety
After-sales service
Maintenance should match available skills
Availability of special tools
Ease of replacement/repair
Readiness to redesign

18. MAINTENANCE MANAGEMENT
IT IS THE JOB
OF THE
MAINTENANCE MANAGEMENT
TO IDENTIFY
THE EXACT REASONS

19. IDENTIFY THE EXACT REASON
FOR THE DELAY
IN YOUR ORGANIZATION
AND ....
of course ...
GIVE A SOLUTION !!!

20. IMPROVING THE SITUATION
YOU WILL BE
IMPROVING THE SITUATION