modern maintenance management indosat

MAINTENANCE MANAGEMENT 1

COMMON MAINTENANCE PROBLEM

Insufficient proactive maintenanceFrequent problem repetitionErroneous maintenance workSound maintenance practice not

institutionalizedUnnecessary and conservative PMSketchy rationale for PM actionsMaintenance program lacks of trace abilityBlind acceptance of OEM inputs


MODERN MAINTENANCE MANAGEMENT

FUNDAMENTAL CONCEPT OF MAINTENANCE 4


Repair to reliability focus

THE CHARACTERISTICS Repair Focused Reliability Focused Fix it Improve it Firefight Predict, Plan, Schedule Manage defects Eliminate Defects Reduce Maintenance Cost Increase Uptime Program of the month Continuous Improvement Believe failures are inevitable Believe failures are exceptional Give priority to breakdowns Give priority to eliminating failures Many failures Few failures Low level of planned work High level of planned work High level of rework Low levels of rework Poor reliability High reliability High maintenance costs Low maintenance cost Short term plans Long term plans Become non-profitable Attract new investments

MAINTENANCE MANAGEMENTDefinition of maintenance

All activities subjected to technical systems to retain or restore the

functional capabilities of the technical system

Modern maintenance management utilizes effective maintenance

techniques to:

integrate all maintenance activities such as, preventive maintenance,

predictive and corrective maintenance

define maintenance action

define maintenance plan and schedules to achieve minimum

maintenance cost.


MAINTENANCE MANAGEMENTMaintenance concept

The development of maintenance concept is the central activity

of maintenance support planning.

The maintenance concept :

defines criteria for maintenance activities

defines resources allowable at each of the specified

maintenance level


MAINTENANCE MANAGEMENTThe maintenance concept serves two purposes:

provide the basis for establishment of maintainability design

requirements

provide the basis for the establishment of maintenance support

requirements in terms of :


MAINTENANCE MANAGEMENT task to be performed

frequency of maintenance

maintenance down time

personnel numbers and skill level

test and support equipment

tools

repair parts

facilities

information


MAINTENANCE MANAGEMENTExample :

if the maintenance policy is that no external test equipment is

allowable for organizational level maintenance, one design

implication is that built-in test features must be incorporated

If the corrective maintenance policy is no repair at the

organizational level except to replace failed items, then the

design implication is the use of modular design to the maximum

extent feasible


MAINTENANCE MANAGEMENT

If the operator or repairman at the organizational level must

monitor, calibrate and adjust his equipment, then adequate training

and technical manuals must be provided along with necessary

calibration and alignment equipment and tools which are not built

into the prime equipment



COVERAGE OF THE MAINTENANCE CONCEPT

A. OPERATIONAL STATES

1. Inactive Period

2. Scheduled Downtime Period

3. Operational Demand Period

Stand-by

Alert

Reaction

Mission

Deactivation


MAINTENANCE MANAGEMENTB.MAINTENANCE ACTIVITIES

1. Preventive Maintenance

Service $ Replacement

Inspection

2. Corrective Maintenance

§ Detection

§ Diagnosis

§ Correction

§ Verification

3. Maintenance Level

§ Organizational


MAINTENANCE MANAGEMENT § Intermediate

§ Depot

C. RESOURCES

1. Personnel

§ Operator

§ Maintenance Technician

2. Equipment

§ Prime

§ Support

3. Facilities

4. Repair Parts and Supplies


MAINTENANCE MANAGEMENT 5. Information ( Publications and Data )

D.EFFECTIVENESS

1. Downtime

§ Detection time

§ Diagnostic time

§ Correction time

§ Verification time

2. Reliability

3. Availability or Operational Readiness


MAINTENANCE MANAGEMENTBASIC MAINTENANCE POLICIES

“HARD-TIME" "ON-CONDITION" COND. MONITORINGPREVENT ANTICIPATE MAX. ANTICIPATE REMEDY


MAINTENANCE

CORRECTIVEMAINTENANCE

PREDICTIVEMAINTENANCE

CONDITION BASEDMAINTENANCE

PERIODIC MAINTENANCE

PREVENTIVEMAINTENANCE

PREVENTIVE MAINTENANCE

What is ?Preventive maintenance is the performance of

inspection and or servicing task that has been preplanned for accomplishment at specific point in time to retain the functional capabilities of operating system

Corrective maintenance is the performance of unplanned maintenance task to restore the functional capabilities of failed or malfunctioning equipment

MAINTENANCE OUTAGE OR BREAKDOWN MAINTENANCE ???


Why? ?


PREVENTFAILURE

DETECT ONSETOF FAILURE

DISCOVER AHIDDEN FAILURE


Task categories

PREVENTIVEMAINTENANCE

TIMEDIRECTED

CONDITIONDIRECTED

FAILUREFINDING

RUN TOFAILURE


Task categories

Aimed directly at failure prevention or retardation Task and periodicity are preset Safe life limit or economic life limit Action is known to directly prevent failure Task action requires some form of intrusion

TIMEDIRECTED


Task categories

Measuring parameters related with incipient failure condition overtime Can identify measurable parameter related to

failure Specify value of parameter related to failure Task is non intrusive to equipment

CONDITIONDIRECTED


Task categories

Uncover the hidden failure at prescheduled check Complex system with redundancy or back-up Economic driven, in lieu of td or cd task

FAILUREFINDING


Task categories

Allow the equipment to operate until it fails ( no preventive maintenance action ever taken ) No pm task effective and applicable Available pm task option is too expensive Failure effect is not essential (safety or economic )

RUN TOFAILURE

MAINTENANCE MANAGEMENTPREVENTIVE VS CORRECTIVE

PREVENTIVE MAINTENANCE :

§ ACTION BEFORE FUNCTIONAL FAILURE

§ PREVENT FUNCTIONAL FAILURE

CORRECTIVE MAINTEANCE :

§ ACTION AFTER FUNCTIONAL FAILURE

§ RESTORE FUNCTIONAL FAILURE

CRITERION : FUNCTIONAL FAILURE DEFINITION

RECORDING: DOWN-TIME, COST, MANHOURS, INTERVAL


MAINTENANCE MANAGEMENTEXAMPLES OF MAINTENANCE POLICIES

1. PREVENTIVE MAINTENANCE ACTION WILL BE PERFORMED ONLY DURING

SCHEDULED DOWNTIME

2. NO MAINTENANCE WILL BE PEFORMED DURING MISSION TIME

3. DURING OPERATIONAL PERIOD, MAINTENANCE WILL BE LIMITED TO

ORGANIZATIONAL REPAIRMAN

4. REPAIRS AT THE ORGANIZATIONAL LEVEL WILL BE MADE BY REPLACEMENT ONLY

5. MAINTENANCE BY OPERATOR WILL BE LIMITED TO SIMPLE DETECTION AND

ROUTINE DIAGNOSTIC TO REPLACE A FAILED MODULE. NO DETAIL TEST AND REPAIR

SKILL WILL BE REQUIRED


MAINTENANCE MANAGEMENT 1. SYSTEM AVAILABILITY WILL BE AT LEAST 0.XXX 2. REPAIR PART WILL BE CARRIED AT ORGANIZATIONAL LEVEL 3. MTTR WILL NOT EXCEED "X" MINUTES 4. MODULES WHOSE REPLACEMENT COST IS MORE THAN "Y: DOLLARS WILL BE

DESIGNED FOR REPAIR 5. MAINTENANCE BY ORGANIZATIONAL REPAIRMEN WILL BE LIMITED TO SIMPLE VISUAL CHECK, INSPECTION, CLEANING, SERVICING, ADJUSTMENT


MAINTENANCE MANAGEMENTLEVELS OF MAINTENANCE

LEVELS OF MAINTENANCE MIGHT BE DEVIDED INTO THREE CATEGORIES:

§ ORGANIZATIONAL MAINTENANCE

§ INTERMEDIATE MAINTENANCE

§ DEPOT MAINTENANCE

A. ORGANIZATIONAL MAINTENANCE

ORGANIZATIONAL MAINTENANCE IS THAT MAINTENANCE NORMALLY

AUTHORIZED FOR, PERFORMED BY, AND RESPOSIBILITY OF, A USING

ORGANIZATION ON EUIPMENT IN ITS POSSESSION.


MAINTENANCE MANAGEMENTIT INCLUDES :

§ INSPECTING

§ SERVICING

§ CLEANING

§ LUBRICATING

§ ADJUSTING

§ REPLACEMENT OF PARTS, MINOR ASSEMBLIES, SUB ASSEMBLIES

ACTIVITIES PERFORMED BY EQUIPMENT OPERATOR AND ORGANIZATIONAL

REPAIRMAN FORWARD REMOVED ITEMS FOR REPAIR TO HIGHER LEVEL


MAINTENANCE MANAGEMENT B. INTERMEDIATE MAINTENANCE

THIS LEVEL OF MAINTENANCE IS LIMITED TO THE REPAIR OF

UNSERVICEABLE ASSEMBLIES IN SUPPPORT OF USING ORGANIZATION ON A

RETURN-TO-USER BASIS

CHARACTERISTICS :

§ FURNISHES SUPPLIES AND SERVICES TO THE USER

§ ORGANIZED AS SEMIFIXED OR PERMANENT SHOP

§ SERVES LOWER LEVELS WITHIN A DESIGNATED GEOGRAPHICAL AREA


MAINTENANCE MANAGEMENT C. DEPOT MAINTENANCE

DEPOT MAINTENANCE IS THE CENTRAL MAINTENANCE FACILITIES AND ACTIVITIES OF THE COMPANY WHICH, THROUGH OVERHAUL OF ECONOMICALLY REPAIRABLE MATERIEL, AUGMENTS THE PROCUREMENT PROGRAM IN SATISFYING OVERALL COMPANY REQUIREMENT

CHARACTERISTICS: § SERVES LARGE GEOGRAPHICAL AREA § MOST COMPLETE FACILITIES § PERFORM SERVICES THAT ARE BEYOND THE CAPABILITIES OF LOWER

LEVEL § PROVIDE MAJOR SUPPLY BASIS


MAINTENANCE MANAGEMENTDESIGN-FAULT DETECTION

IN A CORRECTIVE MAINTENANCE, ACTIVITIES MIGHT BE DEVIDED INTO THE

FOLLOWING SEQUENTIAL TIME PHASES

§ DETECTION TIME (FAULT RECOGNITION)

§ DIAGNOSTIC TIME (FAULT LOCATION & ISOLATION )

§ CORRECTION TIME (REPLACE OR REPAIR )

§ VERIFICATION TIME (TEST AND ALIGN)

DETECTION (AND DIAGNOSTIC) TIME USUALLY CONTRIBUTES SIGNIFICANT

AMOUNT OF TIME TO THE EQUIPMENT DOWN TIME

SO, IT HAS TO BE MINIMIZED !!!


MAINTENANCE MANAGEMENTA FAULT IS ASSUMED TO EXIST UPON THE OCCURRENCE OF ONE OF THE FOLLOWING EVENTS: § DEGRADATION OF PERFORMANCE § CRITICAL FAILURE § CATASTROPHIC FAILURE FAULT DETECTION PROCESS


PARAMETER

STANDARD

SENSOR COMPARATOR INDICATOR DISPLAY

ALARM

MAINTENANCE MANAGEMENTFAULT DETECTION STRATEGIES:

§ AUTOMATIC MONITORING WITH ALARM INDICATION

§ AUTOMATIC FAULT INDICATION WITH ALARM FOR CRITICAL

PARAMETER

§ PERIODIC TEST AND INSPECTION BY MAINTENANCE PERSONNEL

§ PERIODIC SELF-TEST AND CALIBRATION BY THE OPERATOR

§ ABNORMAL OPERATION NOTED BY OPERATOR


MAINTENANCE MANAGEMENTCOST ANALYSIS

ONE OF THE MOST COMPREHENSIVE TOOL FOR COMPARING TWO OR MORE DESIGN

ALTERNATIVES (OR VENDORS) IS THE SYSTEM LIFE CYCLE COST

MODELING

AELCC = PC + OC + RC + SC

AELCC = ANNUAL EQUIVALENT LIFE CYCLE COST

PC = ANNUAL EQUIVALENT POPULATION COST

RC = ANNUAL REPAIR FACILITY COST

OC = ANNUAL OPERATING COST

SC = ANNUAL SHORTAGE PENALTY COST


MAINTENANCE MANAGEMENTPC = CiN

Ci = annual equivalent cost per unit n = retirement age

P = acquisition cost per unit i = interrest rate

F = estimated salvage value of a unit

B = book value of a unit at the end of n year

L = estimated life of the unit

N = number of unit in the population


L

FPnPB

i

iB

i

iiPC

nn

n

i

1)1(1)1(

)1(

MAINTENANCE MANAGEMENTOC = (EC + LC + PMC + Other) N

Where: EC = annual cost of energy LC = annual cost of operating labor PMC = annual cost of preventive maintenance

RC = CrM

Where: Cr= annual fixed and variable repair cost per repair channel

M = number of repair channelSC= Cs[E(S)]


D

jjDNjPSE

1)()(

MAINTENANCE MANAGEMENTTHE STEADY STATE PROBABILITY OF n FAILED UNIT IS

Pn= P0Cn , for n =1, 2,………….N

Where:

IF n = 0,1,2…………..M

IF n = M, M+ 1, M+2 …………….N


n

n nnN

NC

!)!(

!

n

Mnn MMnN

NC

!)!(

!

MAINTENANCE MANAGEMENTAND THE PROBABILIY THAT NO ITEM FAILED, P0

EXAMPLE:SUPPOSE YOU NEED TO DEPLOY 15 IDENTICAL BASE TRANSCEIVER STATION, BUT YOU HAVE NO CONTROL OVER SYSTEM DESIGN (MTBF AND MTTR), BUT CAN ONLY CHOOSE THE NUMBER OF UNIT TO PROCURE, THE RETIREMENT AGE, NUMBER OF REPAIR CHANNELASSUME THE NUMBER TO PROCURE IS 19, REPAIR CHANNEL IS 3 AND THE RETIREMENT AGE IS 4 YEARS


1

00

N

nnCP

MAINTENANCE MANAGEMENTPARAMETER VALUE

Unit Acquisition Cost $52,000Unit Design Life 6 yearsSalvage value at end of design life $7000Unit Operating cost- energy $500- operating labor $450 - preventive maintenance $400 - other $400 Annual repair channel cost $45,000Annual shortage cost $73,000Annual interrest rate 10 %MTBF 300 jamMTTR 50 jamRETIREMENT AGE 4 YEARS


MAINTENANCE MANAGEMENTANNUAL EQUIVALENT POPULATION COST

ANNUAL OPERATING COSTOC= ( $500 + $450 + $400 + $400)(19) = $ 33,250

ANNUAL REPAIR FACILITY COSTRC = $45,000 (3) = $ 135,000


616,221$)19(664,11$

664,11$1)10.1(

10.0000,22$

1)10.1(

)10.1(1.0000,52$

000,22$6

000,7$000,,52$4000,52$

44

4

PC

C

B

i

MAINTENANCE MANAGEMENTANNUAL SHORTAGE

(/) = 1/6 = 0.1667

COMPUTING Cn FOR n = 0,1,..3 (n M )


1665.3)!1(!18

)1667.0(!19

1)!0(!19

)1667.0(!19

1

1

0

0

C

C

COMPUTING Cn FOR n = 4, 5, ……19

MAINTENANCE MANAGEMENTCOMPUTING Cn FOR n = 4, 5, ……19


0000.0)!3()!3(!0

)1667.0(!19

....

....

3224.3)!3()!3(!14

)1667.0(!19

9813.3)!3()!3(!15

)1667.0(!19

19

19

5

5

4

4

C

C

C

19

0

9390.27n

nC


THE PROBABILITY OF NO FAILED ITEM

COMPUTING Pn FROM Pn = P0Cn

P0 = 0.0358 x 1 = 0.0358

P1 = 0.0358 x 3.1665 = 0.1134

…P6 = 0.0358 x 2.5840 = 0.0925

P19 = 0.0358 x 0.000 = 0.0000


0358.09390.27

1119

0

0

n

nCP

MAINTENANCE MANAGEMENTTHE EXPECTED NUMBER OF UNIT SHORT IS

THE ANNUAL SHORTAGE COST IS

SC = Cs [E(S)]

= $73,000(1.00663) = $ 73,484

THE TOTAL SYSTEM ANNUAL EQUIVALENT COST

TC = $221,616 + $33,250 + $135,000 + $73,484 = $463,350


00663.1)0000.0(15.............)0925.0(2)1189.0(1)(

)(1

15

1)4()(

SE

jPjPSED

j jjjDN



RETIREMENT AGE UNIT NUMBER,N

2 CHANNEL 3 CHANNEL 4 CHANNEL

3 19 $598,395 $465,985 $469,130

4 18 $592,920 $464,770 $465,755

4 19 $600,720 $463,350 $464,295

4 20 $610,775 $466,610 $468,755

5 19 $643,050 $480,375 $467,735

MAINTENANCE MANAGEMENTMAINTENANCE COST MODEL

WHERE, W : HOURLY RATE OF SERVICE ENGINEERH : EQUIPMENT USAGE IN HOURS PER PERIOD CONSIDEREDTP

R : SCHEDULED TIME FOR PREVENTIVE MAINTENANCE

TPT : EXPECTED TRAVEL TIME FOR PREVENTIVE MAINTENANCE

TPl : SCHEDULED PREVENTIVE MAINTENANCE INTERVAL

TCT : EXPECTETED TRAVEL TIME FOR CORRECTIVE MAINTENANCE


MTBF

TMTTRWH

T

TTWHICM

CCCMCT

Pl

PT

PR

CRMC

CMPMSPIC

MAINTENANCE MANAGEMENTMTTR : MEAN TIME TO REPAIR

MTBF : MEAN TIME BETWEEN FAILURE

CM : MANUFACTURING COST OF SPARE PARTS

ICR : INVENTORY COST RATE

EXAMPLE:

CONSIDER AN ELECTRONIC EQUIPMENT WITH THE FOLLOWING PARAMETER,

CM = $ 5000 , W = $ 250/hour, H = 4000 HOURS/YEAR, ICR = 50%/YR

MTTR = 0.5 hours, MTBF = 3000 hours,TPR = 0.25 hours, TP

T = 0.5 hours

TPl = 2 months, TC

T = 1.5 hours
