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

Maintenance

All activities that maintain facilities and

equipment in good working order so that

a system can perform as designed to

achieve production/services

To keep production systems in good working

order at minimal cost.

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

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

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

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

Time based

Counter based

Predictive maintenance online

maintenance oil

analysis,Thermogrpahy & vibration

anaylsis etc.

Breakdown and

repair cost

Optimum Amount of

preventive maintenance

Co

st

Total Cost

Preventive

maintenance cost

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

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

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

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

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

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

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

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

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

BD

hrs

BD hrs analysis on EQ B

BD hrs 138 63 50

Percent 55.0 25.1 19.9

EQUIP B BD ANALYSIS

PNEU

MAT

IC C

YLIN

DERS

TRAN

SFER

ARM

FAI

LURE

S

RUBB

ER GUI

DE

250

200

150

100

50

0

100

80

60

40

20

0

BD

hrs

Pe

rce

nt

Pareto Chart of EQUIP B BD ANALYSIS

PNEUM

ATI

C C

YLIN

DER

S

T RANSF

E R A

RM F

AIL

URES

RUBBE

R GUID

E

150

100

50

0

PNE U

MATIC

CYLI

NDERS

T RAN

SFE

R A R

M F

AIL

URES

RUBB

ER

GUID

E

150

100

50

0

count = 6

EQUIP B BD ANALYSIS

BD

hrs

count = 8

count = 14

RUBBER GUIDE

TRANSFER ARM FAILURES

PNEUMATIC CYLINDERS

EQUIP B BD ANALYSIS

Pareto Chart of EQUIP B BD ANALYSIS by count

Thank you

Interaction on Implementation