EFFECTIVENESS OF PREVENTIVE

MAINTENANCE IN CRITICAL

EQUIPMENTS AT APOLLO TYRES

JUSTIN THOMACHAN

INTRODUCTION AND OBJECTIVES.OBJECTIVE

PRIMARY OBJECTIVE:

• To study the effectiveness of Preventive maintenance of critical equipment in Apollo Tyres.

SECONDARY OBJECTIVE:

• To analyse the mechanical down time and identify the opportunities of improvement of availability of critical

equipment.

Critical equipment – Dual Extruder and Calendar.

Tools used :

– OEE (Over all equipment effectiveness).

– OEE = Efficiency x Availability x Quality.

– Pareto Analysis – to find out major break downs.

Data Collection : Ten month’s data is used for analysis. And main emphasis is on secondary data.

– Primary Data :- Personal interview with maintenance department, production department, planning department,

quality control department and Industrial engineering department personals.

– Secondary Data :- Machine logs, Production reports, Company manuals, Industrial engineering journals.

LIMITATIONS.

• Due to confidentiality nature of quality and performance data, it was difficult to get certain details.

• Intervention from the employees union which made collection of data difficult.

OVER ALL EQUIPMENT EFFECTIVENESS

• OEE OF CALENDAR

Month Availability Performance Quality OEE OEE% Avg Avail Avg OEE

Jul-13 0.9803 0.9462 0.996 0.92385 92.38496

     

     

Aug-13 0.9573 0.8911 0.9958 0.849467 84.94672

Sep-13 0.9488 0.9695 0.9957 0.915906 91.59062

Oct-13 0.9095 0.8414 0.9954 0.761733 76.17331

Nov-13 0.9548 0.9305 0.9957 0.884621 88.46211

Dec-13 0.9671 0.9243 0.9958 0.890136 89.01362 0.95298  86.40747

Jan-14 0.9331 0.9629 0.9957 0.894619 89.46185

    

    

Feb-14 0.968 0.8806 0.996 0.849011 84.90111

Mar-14 0.9347 0.906 0.9962 0.84362 84.36202

Apr-14 0.9762 0.8512 0.9962 0.827784 82.77839

• OEE OF DUAL EXTRUDER

Month Availability Performance Quality OEE OEE% Avg Avail Avg OEE

Jul-13 0.977 0.9221 0.916 0.82522 82.52

   

Aug-13 0.9091 0.8814 0.965 0.77324 77.32

Sep-13 0.9154 0.9121 0.932 0.77816 77.81

Oct-13 0.9264 0.8254 0.968 0.74018 74.01

Nov-13 0.9672 0.9157 0.956 0.8467 84.67

Dec-13 0.9034 0.9262 0.983 0.8225 82.25 0.928 79.11

Jan-14 0.9084 0.8949 0.968 0.78691 78.69

   

Feb-14 0.922 0.8493 0.986 0.77209 77.2

Mar-14 0.9081 0.878 0.971 0.77419 77.41

Apr-14 0.945 0.8656 0.979 0.7924 79.23

BREAK DOWN ANALYSIS

Calendar.

• Total mechanical down = 306.67 hrs.

• From Pareto analysis we found out top 5

downtimes.

• That are Mill failure, Led off Feed roll break

failures, Feed conveyor related failures, mill

guide failures, Roller failures.

Dual Extruder

Total mechanical down = 541.43 hrs.

From Pareto analysis we found out top 5

downtimes.

That are Skiver not skiving, Mill break down,

head related general failures, Cooling

conveyor joint failures, belt conveyor failures.

Skiver not skiving

Mill break down

Head related general failure

cooling conveyor joint failure

Belt conveyor failure

feeding mill break down

temprature fluctuation in TCU

Roller conceyor failure

speed fluctuation

Head rubber leakage

Rubber Jam

 Between Coveyor and roller

Skiver angle variation

stock loader failure

0

2000

4000

6000

8000

020406080100

Mill Failure

feed conveyor related

roller failure

 wind up acctuator roller bearing related

let off acctuator chain unbalance

center guide,hydraulic cylinder oil leak

winder chuck failure

acctuator hydraulic cylinder oil leak

wind up feed  cylider air leak.

wind up acctuator roller bearing failures

web m

aster roll jammed rolling

let of acc sprocker shifting

0100020003000400050006000

020406080100

FINDINGSCALENDAR

• The major five failures are Mill failure, Led off Feed roll break failures, Feed conveyor related failures, mill guide failures, Roller failures.

• After eliminating these failures:– 72.15% of reduction in total

mechanical break down.– 3.385% increase in availability, i.e. to

98.67%.– 3.07% increase in OEE, I.e. to 89.44%.– Rs. 94667.1 reduction in terms of man

power cost.

DUAL EXTRUDER.• The major five failures are Skiver

not skiving, Mill break down, head related general failures, Cooling conveyor joint failures, belt conveyor failures.

• After eliminating these failures:– 80.12% of reduction in total

mechanical break down.– 6.9% increase in availability, i.e. to

99.72%.– 5.93% increase in OEE, I.e. to 85.04%.– Rs. 122067.3 reduction in terms of

man power cost.

SUGGESTIONS