Optimization of preventive maintenance to reduce maintenance costs and increase equipment availability

2.  What is preventive maintenance?
 · Overview of the types of preventive
maintenance
 · Identifying ideal preventive maintenance
 · A practical approach to optimise equipment
availability
 · Techniques for optimisation

3. Maintenance
All activities that maintain facilities and
equipment in good working order so that
a system can perform as designed to
achieve production/services

4.  To keep production systems in good working
order at minimal cost.

5. Reactive Maintenance:
 Breakdown maintenance
 Reactive approach; dealing with breakdowns or
problems when they occur
Proactive Maintenance:
 Preventive maintenance
 Proactive approach; reducing breakdowns through
a program of lubrication, adjustment, cleaning,
inspection, and replacement of worn parts

6.  Production capacity is reduced
 Orders are delayed
 No production
 Overhead continues
 Cost per unit increases
 Quality issues
 Product may be damaged
 Safety issues
 Injury to employees
 Injury to customers

7.  Preventive maintenance: goal is to reduce the
incidence of breakdowns or failures in the plant or
equipment to avoid the associated costs
 Preventive maintenance is periodic
 Result of planned inspections
 According to calendar
 After predetermined number of hours
 All actions are prevent to failure

8.  Predictive maintenance
 An attempt to determine when best to perform
preventive maintenance activities
 Total productive maintenance
 JIT approach where all stakeholders perform
preventive maintenance on the machines they operate

9. Time based
Counter based
Predictive maintenance online
maintenance oil
analysis,Thermogrpahy & vibration
anaylsis etc.

10. Breakdown and
repair cost
Optimum Amount of
preventive maintenance
Cost
Total Cost
Preventive
maintenance cost

11. Frequency of breakdown
If the average cost of a breakdown is $1,000, and
the cost of preventative maintenance is $1,250 per
month, should we use preventive maintenance?
Number of breakdowns 0 1 2 3
Frequency of occurrence .20 .30 .40 .10

12. Number of
Breakdowns
Frequency of
Occurrence
Expected number of
Breakdowns
0
1
2
3
.20
.30
.40
.10
1.00
0
.30
.80
.30
1.40
Expected cost to repair = 1.4 breakdowns per month X $1000 = $1400
Preventive maintenance = $1250
PM results in savings of $150 per month

13.  Normally PM duration and frequency are
evaluated by following manner
 OEM recommendations
 Past expereicne
 Both have additional ideal time to have better
PM in the mind of 100 % equipment availability
even some of equipments/facilities not
required

14. IDEAL PM CALCULATION SUMMARY
SI.NO EQUIPMENT PM FREQUENCY PM DURATION EQUIPMENT CATEGORY REQUIRED EA
1 EQP A M+ Q 10 NON CRITICAL 50.00
2 EQP B M+ Q 18 MEDIUM CRITICAL 85.00
3 EQP C M+ Q 10 CRITICAL 85.00
4 EQP D BI AN + ANNUAL 36 NON CRITICAL 50.00
5 EQP E W+M+Q 18 CRITICAL 85.00
6 EQP F W+M+Q 18 CRITICAL 85.00
7 EQP G W+M+Q 18 NON CRITICAL 85.00

16.  Differentiation between critical & non critical
equipment's PM Plan
 PM Strategy based on essential
 PM frequency based on equipment
performance
 Including weekly inspection /predictive
approach for critical & most critical
equipments

17. PRACTICAL APPROACH PM CALCULATION ANALYSIS VS IDEAL
SI.NO EQUIPMENT PM FREQUENCY PM DURATION EQUIPMENT CATEGORY REQUIRED EA Current EA BD hrs
1 EQP A M+ Q 10 NON CRITICAL 50% 100% 0
2 EQP B M+ Q 18 MEDIUM CRITICAL 85% 65% 252
3 EQP C M+ Q 10 CRITICAL 85% 75% 180
4 EQP D BI AN + ANNUAL 36 NON CRITICAL 50% 100% 0
5 EQP E W+M+Q 18 CRITICAL 85% 65% 252
6 EQP F W+M+Q 18 CRITICAL 85% 65% 252
7 EQP G W+M+Q 18 NON CRITICAL 85% 100% 0

18. Optimization based on analysis
SI.NO EQUIPMENT PM FREQUENCY PM DURATION EQUIPMENT CATEGORY REQUIRED EA Current EA
BD
hrs
1 EQP A Q 6 NON CRITICAL 50% 99% 2
2 EQP B W+M+ Q 26 MEDIUM CRITICAL 85% 86% 100.8
PM increase on
EQ B
8 hr
BD reduces on
EQ B
151.2

19. EQUIP B BD ANALYSIS ( TRANSFER ARM,RUBBER GUIDE & PNEUMATIC CYLINDERS)
SI.NO EQUIP E BD ANALYSIS BD hrs % Reason
1 RUBBER GUIDE 138.6 0.55
2 TRANSFER ARM FAILURES 63 0.25
due to nature of operations /services
damages occurs every 144 hrs
3 PNEUMATIC CYLINDERS 50.4 0.2

20. RUBBER GUIDE TRANSFER ARM FAILURES PNEUMATIC CYLINDERS
1 2 3
BD hrs 138.6 63 50.4
0
20
40
60
80
100
120
140
160
BDhrs
BD hrs analysis on EQ B

21. BD hrs 138 63 50
Percent 55.0 25.1 19.9
EQUIP B BD ANALYSIS
PNEUM
ATIC
CYLINDERS
TRANSFER
ARM
FAILURES
RUBBER
GUIDE
250
200
150
100
50
0
100
80
60
40
20
0
BDhrs
Percent
Pareto Chart of EQUIP B BD ANALYSIS

22. PN
E
U
M
A
TIC
C
YLIN
D
ER
S
TR
A
N
SFE R
A
RM
FA
ILU
R
ES
RU
B
BER
G
U
ID
E
150
100
50
0
P
N
E U
M
A
T
IC
CY
LIN
D
E
RS
TR
AN
S
FE R
AR
M
F
A
ILU
R
ES
RU
BBE
R
G
U
ID
E
150
100
50
0
count = 6
EQUIP B BD ANALYSIS
BDhrs
count = 8
count = 14
RUBBER GUIDE
TRANSFER ARM FAILURES
PNEUMATIC CYLINDERS
EQUIP B BD ANALYSIS
Pareto Chart of EQUIP B BD ANALYSIS by count

23.  Thank you
 Interaction on Implementation