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InspectionInspection--based based Preventive MaintenancePreventive Maintenance

Paul Dean CEng Shire Systems Limited


Topics in this presentationTopics in this presentation……

The fundamental choice The fundamental choice –– organisationorganisation or or chaoschaos

The effect of reactive maintenance on costsThe effect of reactive maintenance on costs

The 5 causes of breakdownsThe 5 causes of breakdowns

Equipment deterioration & fitness for purposeEquipment deterioration & fitness for purpose

The pattern of deterioration The pattern of deterioration –– Condition IndexCondition Index

Getting going with condition inspectionGetting going with condition inspection

The true corrective maintenance repair backlogThe true corrective maintenance repair backlog

Gaining spanner time from planning & schedulingGaining spanner time from planning & scheduling


First, I’d like to tell you a story –it’s a tragedy…


…Company XYZ Ltd installed a new asset – it was bright and shiny and did its job very well…


Wear!

Vibration!

…after a while some of its parts became worn and it started to vibrate – but everyone ignored its distress and nobody came to fix it…


Wear!

Leak!

…in a little while longer it started to leak oil - but everyone ignored its distress and nobody came to fix it…

Vibration!


…then it started to overheat - but everyone ignored its distress and nobody came to fix it…

Wear!

Leak!

Heat!

Vibration!


BREAKDOWN!

…so it broke down. Then EVERYONE came to see what was wrong - and somebody even came to fix it…


Fix me NOW!

…the asset realised that the only way to get attention was to break down. So it got mean and did –frequently. Other assets joined the game…


Fix me NOW!

The name of the game is reactive maintenance!The name of the game is reactive maintenance!


In the REACTIVE MAINTENANCEenvironment the equipment dictates

to the maintenance team what to do and when to do it

It’s SO demoralising…

The members of the maintenance team

have to respond like automatons


…and suicidal!

Production and service delivery

Quality

Health, Safety & Environmental compliance

Public image

Costly

Risky &

UNSUSTAINABLE


Later in Company XYZ Ltd…

Because of the incessant equipment breakdowns, prime quality production plummeted, operating costs soared and market share collapsed. The Company was fined heavily for violating pollution laws and, following a fatal accident, is being prosecuted for corporate manslaughter.

THE END


A strange conundrum


A strange conundrumA strange conundrum……

Fact Most equipment failures are predictable and most disruptive failures are avoidable

Query Why then is most corrective maintenance work in most organisations reactive and unplanned?

Sad answer Failure to manage the process of asset deterioration - due to a fundamental lack of discipline and systematic work methods


Your basic choice…organisation or chaos


Forms of maintenanceForms of maintenance

Maintenance

Planned maintenance

Unplanned maintenance

Preventive maintenance

Scheduled maintenance

Condition basedmaintenance

Corrective(including deferred)

maintenance

Corrective(including emergency)

maintenance

= ‘organisation’

Reference: BS 4778



Maintenance

Planned maintenance






maintenance


maintenance

Jobs planned in advance, precisely

organised & controlled

Reference: BS 4778



Maintenance

Planned maintenance






maintenance


maintenance

Jobs planned in advance, precisely

organised & controlledIncluding…

jobs

Reference: BS 4778



Reference: BS 4778

Maintenance

Planned maintenance






maintenance


maintenance

It’s the preferred form of PM!



Reference: BS 4778

Maintenance

Planned maintenance






maintenance


maintenance

‘On-condition’ monitoring of PARAMETERSdirectly related to

equipment condition



Reference: BS 4778

Maintenance

Planned maintenance






maintenance


maintenance

Non-invasive

Invasive maintenance can embed failure-initiating

defects in the equipment

Invasive maintenance can embed failure-initiating

defects in the equipment

‘On-condition’ monitoring of PARAMETERSdirectly related to

equipment condition



Reference: BS 4778

Maintenance

Planned maintenance






maintenance


maintenance

Includes‘5 senses’inspection



Maintenance

Planned maintenance






maintenance


maintenance

OR

= ‘chaos’

…where ‘emergency’ work

predominates

…where ‘emergency’ work

predominates

Reference: BS 4778



Maintenance

Planned maintenance






maintenance


maintenance

Reacting to sudden failure – it’s chaotic & often done in a panic

Reference: BS 4778



Reference: BS 4778

Maintenance

Planned maintenance






maintenance


maintenance

The cost multipliers are 1.5 to 10 times

Compared with a planned job!

Compared with a planned job!



Maintenance

Planned maintenance






maintenance


maintenance

It’s exacerbated by the lack of

inclination to plan!

The central tendency in maintenance is to react,

not plan. A mindset change is needed!

The cost multipliers are 1.5 to 10 times

Reference: BS 4778


Unplanned emergency work Unplanned emergency work –– the consequences ofthe consequences of……Reactive maintenance

Prime quality production & service is automatically jeopardisedPrime quality production & service is automatically jeopardisedWorker and often public health & safety is compromised. Worker and often public health & safety is compromised. Disasters & personal tragedy caused by failure to maintain Disasters & personal tragedy caused by failure to maintain equipment integrityequipment integrity are a constant topic in the mediaare a constant topic in the mediaCosts are excessiveCosts are excessive because of aggravated and collateral because of aggravated and collateral damage, including catastrophic failure. Cost multipliers can damage, including catastrophic failure. Cost multipliers can easily be up to 10 times easily be up to 10 times –– but the skybut the sky’’s the limit as its just a s the limit as its just a matter of luckmatter of luckDecisions are made on the hoofDecisions are made on the hoof -- work starts without the proper work starts without the proper parts, skills and technical informationparts, skills and technical informationWorking efficiency is lowWorking efficiency is low and other important work is interrupted and other important work is interrupted to plunder resourcesto plunder resourcesThe quality of repairs are poorThe quality of repairs are poor -- equipment reliability declinesequipment reliability declinesThe useful life of equipment is shortenedThe useful life of equipment is shortened


Facing the fundamental choiceFacing the fundamental choice……

Maintenance

Planned maintenance






maintenance


maintenance

It’s YOURpersonal decision

OR

Reference: BS 4778


Facing the fundamental choiceFacing the fundamental choice……

Maintenance

Planned maintenance






maintenance


maintenance

All you really need is commitment &

persistence

ORIt’s YOUR

personal decision

Reference: BS 4778


The effect of emergency reactive maintenance on costs

Can ANYBODY actually afford reactive maintenance?


How emergency work affects total maintenance costsHow emergency work affects total maintenance costs

0

Cos

t of m

aint

enan

ce (£

)

Inspection based

Reactive World class

1 2 3

Consider 3 alternative

maintenance regimes



0

Cos

t of m

aint

enan

ce (£

)

Inspection based


Consider 3 alternative

maintenance regimes

1 2 3 But what’s world class?



0

Cos

t of m

aint

enan

ce (£

)

Inspection based


1 2 3

In the 21st century, competitive advantage is increasingly

dependent on asset management proficiency

High reliability and availability of

physical assets is an absolute need



0

Cos

t of m

aint

enan

ce (£

)

Inspection based


1 2 3

‘World class’ just means you’re applying the proven asset management best practices that are most

appropriate to the success of your type of business

Your business is threatened each time a

competitor adopts a maintenance best practice

you don’t use…



0

Emergency

Unplanned corrective

Planned corrective

PM

Cos

t of m

aint

enan

ce (£

)

Inspection based


60%

35%

4%

1%

Don’t worry about the

precise numbers –

they’re just indicative



0

Cos

t of m

aint

enan

ce (£

)

Inspection based


60%

35%

4%

1%

Emergency


Planned corrective

PMDon’t worry about the

exact numbers –

they’re just indicativeThere are NEVER enough

resources to cope with repair demands in the reactive

maintenance environment…



0

Cos

t of m

aint

enan

ce (£

)

Inspection based


60%

35%

4%

1%

Emergency


Planned corrective

PMDon’t worry about the

exact numbers –

they’re just indicative

When costs are double what they should be and equipment reliability is abysmal as a

result of reactive maintenance, you’ll find it difficult to get approval for more resources.

The resources needed must be gradually freed up by proper work planning &

scheduling and other improvements in working efficiency



0

Cos

t of m

aint

enan

ce (£

)

Emergency


Planned corrective

PM

Inspection based


30%

60%

10%



0

Cos

t of m

aint

enan

ce (£

)

Emergency


Planned corrective

PM

Inspection based


First base –gain control of failure

NO SURPRISES



0

Cos

t of m

aint

enan

ce (£

)

Emergency


Planned corrective

PM

Inspection based


First base –gain control of failure

NO SURPRISES Business processes must be predictable - so, unless you first get control of disruptive failure, you’re

not going anywhere!



0

Cos

t of m

aint

enan

ce (£

)

Emergency


Planned corrective

PM

Inspection based


Costs cut by a third!



0

Cos

t of m

aint

enan

ce (£

)

5%

90%

5%

Emergency


Planned corrective

PM

Inspection based




0

Cos

t of m

aint

enan

ce (£

)

Emergency


Planned corrective

PM

Inspection based


LeanAgile

Best value6 σ

All achievable targets –provided that you’ve passed the first base



0

Cos

t of m

aint

enan

ce (£

)

Emergency


Planned corrective

PM

Costs halved!

Inspection based


AT LEAST

It can be more in a 24/7 operation because shift

cover can be dramatically reduced

It can be more in a 24/7 operation because shift

cover can be dramatically reduced



0

Cos

t of m

aint

enan

ce (£

)

Emergency


Planned corrective

PM

Inspection based


It’s a moving target – you can’t stand

still!

Best practices are constantly being improved and new

ones added – human creativity & ingenuity drive continuous improvement


The strategic choicesThe strategic choices……

Inspection based

Reactive World class0

??



Inspection based


At last I’m in control!

OROR



Inspection based



6 σ

THENTHEN



Inspection based



6 σ

Moving from Reactive first takes a DECISION - then

commitment & persistence to

follow it through

That’s white knuckle persistence!


BreakdownsBreakdowns

Emergency work arises from in-service failures - BREAKDOWNS – exacerbated by the lack of inclination to plan.

Why all the breakdowns? Do they have dominant common causes?

YES!


The 5 causes of equipment BreakdownsThe 5 causes of equipment Breakdowns

POOR

SKILLS &

HUMAN ERROR

5

DESIGN

& ‘DAY 1’

DEFECTS

4

LACK

OR

IGNORE

PROCEDURES

3

IGNORE

DETERIORATION

2

LACK OF

CARE

& SERVICING

1

Self-inflicted burdensholding back better asset performance…



POOR

SKILLS &

HUMAN ERROR

5

DESIGN

& ‘DAY 1’

DEFECTS

4

LACK

OR

IGNORE

PROCEDURES

3

IGNORE

DETERIORATION

2

LACK OF

CARE

& SERVICING

1

In-service failures are due to

error, neglect, abuse & ineptitude!




POOR

SKILLS &

HUMAN ERROR

5

DESIGN

& ‘DAY 1’

DEFECTS

4

LACK

OR

IGNORE

PROCEDURES

3

IGNORE

DETERIORATION

2

LACK OF

CARE

& SERVICING

1

Human failings


(after Nakajima)



(after Nakajima)

POOR

SKILLS &

HUMAN ERROR

5

DESIGN

& ‘DAY 1’

DEFECTS

4

LACK

OR

IGNORE

PROCEDURES

3

IGNORE

DETERIORATION

2

LACK OF

CARE

& SERVICING

1


The countermeasures to breakdowns are fully provided for in the TPM framework

proposed by Seiichi Nakajima - the father of TPM. See his book ‘Introduction to TPM’ published by Productivity Press



POOR

SKILLS &

HUMAN ERROR

5

DESIGN

& ‘DAY 1’

DEFECTS

4

LACK

OR

IGNORE

PROCEDURES

3

IGNORE

DETERIORATION

2

LACK OF

CARE

& SERVICING

1

2 breakdowns causes are

most dominant…




POOR

SKILLS &

HUMAN ERROR

5

DESIGN

& ‘DAY 1’

DEFECTS

4

LACK

OR

IGNORE

PROCEDURES

3

IGNORE

DETERIORATION

2

LACK OF

CARE

& SERVICING

1




IGNORE

DETERIORATION

2

LACK OF

CARE

& SERVICING

1


These two forms of ABUSE & NEGLECT combine viciously

to result in appalling equipment reliability and eye-popping maintenance costs



IGNORE

DETERIORATION

2

LACK OF

CARE

& SERVICING

1

Self-inflicted burdensholding back better asset performance… Tell us

about it!These two forms of ABUSE & NEGLECT combine viciously

to result in appalling equipment reliability and eye-popping maintenance costs


IGNORE

DETERIORATION

2

BUT NEVER FORGET THE

OTHERS…

The Breakdown cause currently in questionThe Breakdown cause currently in question……


Deterioration?Deterioration?

IGNORE

DETERIORATION

2

‘Falling from a higher to a lower level in quality, usefulness or value. To grow worse.’

Deterioration is a decrease in fitness for purpose

Dictionary definition -

In asset maintenance terms -

This has deep implications for ASSET MANAGEMENT

- as distinct from MRO!

Maintenance Repair & Overhaul


IGNORE

DETERIORATION

2

Deterioration & fitness for purposeDeterioration & fitness for purpose

A decrease in fitness for purpose can arise from:1. Natural degradation - entropy

The deterioration that maintenance SHOULD

be controlling


IGNORE

DETERIORATION

2



2. Accelerated degradation – neglect & abuse

The deterioration that most maintenance work is about - & which doubles costs!


IGNORE

DETERIORATION

2



2. Accelerated degradation – neglect & abuse

3. Aggravated degradation – inept repairs, uncontrolled modifications, incidental damage, vandalism, sabotage (extrinsic events)

and also


Equipment fitness for purpose?Equipment fitness for purpose?

Fitnessfor

purpose

Equipment OEE> 85%

Equipment complies with ALL applicable

Regulations

Overall Equipment Effectiveness


Equipment fitness for purposeEquipment fitness for purposehas 3 dimensions…

Fitnessfor

purposeSufficiency

0 –200%

+

1

Com

plia

nce

= 10

0%2

Condition 0 – 100%

3Essential production &

service delivery capability



Fitnessfor

purposeSufficiency

0 –200%

+

1

Com

plia

nce

= 10

0%2




Design configuration and materials of construction must provide inherent functionality

that is fit for purpose



Fitnessfor

purposeSufficiency

0 –200%

+

1

Com

plia

nce

= 10

0%2




Design configuration and materials of construction must provide inherent functionality

that is fit for purpose

Equipment can have SUFFICIENT, LESS or

MORE capability for current needs & can be

‘rated’ accordingly



Fitnessfor

purposeSufficiency

0 –200%

+

1

Com

plia

nce

= 10

0%2


3 SHE (Safety, Health, Environment) and

other integrity functions demanded

by external authorities



Fitnessfor

purposeSufficiency

0 –200%

+

1

Com

plia

nce

= 10

0%2


3 SHE (Safety, Health, Environment) and

other integrity functions demanded

by external authorities

Again, design configuration and materials of

construction must provide inherent functionality that is

fit for purpose

You’re either compliant or not!



Fitnessfor

purposeSufficiency

0 –200%

+

1

Com

plia

nce

= 10

0%2


3

Condition is the basis of an asset’s currently available

functionality



Fitnessfor

purposeSufficiency

0 –200%

+

1

Com

plia

nce

= 10

0%2


3All assets derive their available functionality from the degree of integrity of

their maintained state

Condition is the basis of an asset’s currently available

functionality


Due Diligence & fitness for purposeDue Diligence & fitness for purposeA systems approach is needed…

Due Diligence requires that management of equipment Due Diligence requires that management of equipment fitness for purpose takes account of all credible threats:fitness for purpose takes account of all credible threats:

Natural & accelerated degradationNatural & accelerated degradation

Inappropriate or unauthorised Inappropriate or unauthorised configuration changes (modifications),configuration changes (modifications),

Human errorHuman error

ViolationsViolations

Vandalism/sabotageVandalism/sabotage

Inspection tasks should seek to discover

defects arising from all credible causes…


‘‘5 senses5 senses’’ inspection & due diligenceinspection & due diligence

5 senses inspection

Distress (= deterioration)

Damage

Configuration violations

Integrity of previous repairs

Due Diligence -not Derelict Indifference

Uncontrolled modificationsUncontrolled changes to set pointsOverridden operational safeguardsSafety & other regulatory non-compliances

PLUS


Countermeasures to deteriorationCountermeasures to deterioration……

IGNORE

DETERIORATION

2

So what are the essential

countermeasures


IGNORE

DETERIORATION

2

Countermeasures to deteriorationCountermeasures to deterioration……

123

45

678910

1112

Early

Early

defect discoverydefect repair+

There are twoThere are two……


Gaining control of equipment deterioration


Gaining control of deteriorationGaining control of deterioration- the simple enabling process…

1. Early defect discovery - inspection

S

U

G

= P 2. Corrective repair prioritisation

XYZ

3. Repair planning & scheduling


1. Early defect discovery (inspection)1. Early defect discovery (inspection)

A competent person periodically inspects assets to discover any evident distress/defect that could lead to an in-service failure (and any current non-compliant condition)

Mainly by ‘5 senses’ inspection - with visual inspection being predominant. Hi-tech methods are applied wherever

they are cost effective


1. Early defect discovery (inspection)1. Early defect discovery (inspection)…this underpins the success of any PM programme, yet it’s

the most neglected maintenance activity



1. Early defect discovery (inspection)1. Early defect discovery (inspection)

Unless you arevigilant to developing distress,

disruption is inevitabledefects will announce themselves

- as in-service failures!

Take control or be controlled!



2. Corrective repair prioritisation2. Corrective repair prioritisation

S

U

G

= P

Each discovered defect is risk assessed for seriousness, urgency and growth and the priority of its corrective repair decided


2. Corrective repair prioritisation2. Corrective repair prioritisation

S

U

G

= P

…the considerations are: 1. Criticality of the host asset2. Safety implications of its current state 3. Shape/slope of its ‘deterioration’ curve4. Extent of the defect

We’ll come to this laterEach discovered defect is risk

assessed for seriousness, urgency and growth and the priority of its corrective repair decided


3. Repair planning and scheduling3. Repair planning and scheduling

Corrective repairs are scheduled and launched at a time that avoids in-service failure, causes minimum disruption to operations and incurs least expense

XYZ


3. Repair planning and scheduling3. Repair planning and scheduling

Corrective repairs are scheduled and launched at a time that avoids in-service failure, causes minimum disruption to operations and incurs least expense

XYZ

…planning and scheduling liberates management time and spanner time to carry out more high-value work


And now some theory…

The pattern of deterioration & failure


Bath tub failure curveBath tub failure curve

WEAROUTNORMAL OPERATION

‘WEARIN’

r a n d o m f a I l u r e

The curve relates the probability of failure with the

operating hours or age of an asset

Note – it’s a simplistic model!

infant mortality & ‘teething’problems

failu

re ra

te -

failu

res

per m

onth

operating hours (age)




‘WEARIN’


despite the 6 overall failure patterns recognised in

RCM, the bath tub is still a valid and compelling model

Note – it’s a simplistic model!


failu

re ra

te -

failu

res

per m

onth



Bath tub failure curveBath tub failure curveNote – it’s a simplistic model!


‘WEARIN’



The high initial failure probability of new equipment is unacceptable

‘waste’ and can be avoided by Early Management – the 5th pillar of TPM. Note that invasive maintenance also

increases failure probability

failu

re ra

te -

failu

res

per m

onth





‘WEARIN’

A developing failure at ANY stage follows a

regular patternDeterioration curve of an

itemcond

ition

time

failu

re ra

te -

failu

res

per m

onth



Natural deterioration & failureNatural deterioration & failure

Time0

Trajectory of deterioration

Deterioration curve of a failing item

Very good condition

Con

ditio

n

Point of Functional Failure


The failure process has 3 stagesThe failure process has 3 stages

3. Failure

1. Initiation

2. Progression

Con

ditio

n

0

Time


Repair costs increase when correction is deferredRepair costs increase when correction is deferred

Cost

of r

epai

r £

As deterioration increases, the cost of its

repair generally increases

Cos

t of r

epai

r (£)

Con

ditio

n

0

Time


Early defect discovery & early repair slashes costsEarly defect discovery & early repair slashes costs

Cost

of r

epai

r £

Discover & repair a developing

defect at an early stage and the cost

is a fraction of a late stage repair

£ cost of increasingly later repair£ cost of

early repair

Cos

t of r

epai

r (£)

Con

ditio

n

0

Time


Early defect discovery & early repair slashes costsEarly defect discovery & early repair slashes costs

Cost

of r

epai

r £

£ cost of increasingly later repair

NOTE: The cost of any collateral

damage must be added to this

£ cost of early repair

Cos

t of r

epai

r (£)

Con

ditio

n

0

Time


There can be partial failuresThere can be partial failures……

0


Point of Partial Failure

Con

ditio

n

Time



0



A Partial Failure is loss of performance but not of total function

Con

ditio

n

Time



0


It’s insidious, so BEWARE!

Widespread loss of performance can bring production to its knees – the

aggregation of speed losses, quality losses, etc can devastate equipment OEE – but the equipment still ‘works’

Widespread loss of performance can bring production to its knees – the

aggregation of speed losses, quality losses, etc can devastate equipment OEE – but the equipment still ‘works’


A Partial Failure is loss of performance but not of total function

Con

ditio

n

Time


Distress signals the presence of a developing failureDistress signals the presence of a developing failure……

0

Point of detectable distress

(Potential Failure)



Con

ditio

n

Time


HiHi--tech CM methods buy timetech CM methods buy timeE.g. Bearing distress & failure…

0

Points of detectable developing failure (evident distress)

Choose the inspection Choose the inspection (distress discovery) (distress discovery) technique that will give technique that will give sufficient early warning to sufficient early warning to schedule a repair with schedule a repair with minimum disruption and at minimum disruption and at least expenseleast expense

Vibration monitoring

Lube analysis

5 senses inspection


Con

ditio

n

Time


HiHi--tech CM methods buy timetech CM methods buy timeBearing distress & failure…

0


Lube analysis

5 senses inspection


Note: Depending on the type of equipment, lube analysis could give an earlier warning than vibration parameters

Con

ditio

n

Time


HiHi--tech CM methods buy timetech CM methods buy timeBearing distress & failure…

0



Lube analysis

5 senses inspection

Time ‘gained’

Hi-tech inspection buys you time to

analyse the problem & plan repair

Con

ditio

n

Time


HiHi--tech CM methods buy timetech CM methods buy time

0


Bearing distress & failure…


Lube analysis

5 senses inspectionThe time ‘gained’ should be used to good effect – if not, it delivers no benefit & just adds to cost. 5 senses inspection

may be more appropriate

Are CM technologies adding to costs or reducing costs?C

ondi

tion

Time ‘gained’

Hi-tech inspection buys you time to

analyse the problem & plan repair

Costs

Time

Time


The condition of an item can be The condition of an item can be ‘‘ratedrated’’ or or ‘‘scoredscored’’

0

very poorvery poor

poorpoor

fairfair

goodgood

very goodvery good5

4

Con

ditio

n 3

2

1

Time


The condition of an item can be The condition of an item can be ‘‘ratedrated’’ or or ‘‘scoredscored’’

0

very poorvery poor

poorpoor

fairfair

goodgood

very goodvery good5

4

Con

ditio

n 3

Condition can be scored on a 0-5, 0-100 or 0-1000

scale, as preferred

2

1

Time


The The ‘‘PP--FF’’ intervalinterval

0

very poorvery poor

poorpoor

fairfair

goodgood

very goodvery good

P-F interval

P-F is the time interval from the point of Potential Failure

(detectable distress) to ultimate Functional Failure

5

4

Con

ditio

n 3

2

1

Time


Inspection tracks deterioration in the PInspection tracks deterioration in the P--F intervalF interval

very poorvery poor

poorpoor

fairfair

goodgood

very goodvery good

P-F interval

This is the arena of interest for Inspection (condition monitoring)

activities. The time period between inspections must be

less than the P-F interval!

5

4

Con

ditio

n 3

2

1

0 Time


‘‘ScoringScoring’’ condition condition –– ConditionCondition IndexIndexCondition

ZoneCondition

Index Condition Description Notes Maintenance Action

85 to 100Very GoodNo noticeable defects. Some ageing or wear visible

70 to 84GoodOnly minor deterioration or defects are evident

55 to 69FairSome deterioration or defects are evident, but function not significantly affected

40 to 59MarginalModerate deterioration. Function is still adequate

25 to 39PoorSerious deterioration of some parts. Function is inadequate

10 to 24Very PoorExtensive deterioration. Barely functional. Failure imminent

1 to 9FailedNo longer functions. General failure or complete failure of a major component

0Non-existentAsset abandoned or no longer exists

Disinvest asset and update records

Destruct & disinvest

Detailed evaluation is required to determine the scope of necessary repair, refurbishment or renewal. Health & Safety evaluation is essential

Refurbish or renew

Red

Economic analysis of repair alternatives is recommended to determine appropriate action

Repair defects

(plus cyclic basic care)Yellow

Precautionary minor repairs may sometimes be advisable to arrest deterioration

Cyclic basic care

Green

By means of calibrated inspection, the changes in equipment condition can be

tracked over time. Actions & alerts in response to predefined condition states

can be automated and maintenance budgets calculated & allocated in strict

accordance with business needs

By means of calibrated inspection, the changes in equipment condition can be

tracked over time. Actions & alerts in response to predefined condition states

can be automated and maintenance budgets calculated & allocated in strict

accordance with business needs

By quantifying condition you can track & trend the Condition Index (CI) of an asset, an asset group or the total asset population


‘‘ScoringScoring’’ condition condition –– ConditionCondition IndexIndexCondition

ZoneCondition

Index Condition Description Notes Maintenance Action

85 to 100Very GoodNo noticeable defects. Some ageing or wear visible

70 to 84GoodOnly minor deterioration or defects are evident

55 to 69FairSome deterioration or defects are evident, but function not significantly affected

40 to 59MarginalModerate deterioration. Function is still adequate

25 to 39PoorSerious deterioration of some parts. Function is inadequate

10 to 24Very PoorExtensive deterioration. Barely functional. Failure imminent

1 to 9FailedNo longer functions. General failure or complete failure of a major component

0Non-existentAsset abandoned or no longer exists

Disinvest asset and update records

Destruct & disinvest

Detailed evaluation is required to determine the scope of necessary repair, refurbishment or renewal. Health & Safety evaluation is essential

Refurbish or renew

Red

Economic analysis of repair alternatives is recommended to determine appropriate action

Repair defects

(plus cyclic basic care)Yellow

Precautionary minor repairs may sometimes be advisable to arrest deterioration

Cyclic basic care

Green


A word of cautionA word of caution……

When the average conditionof the asset population drops below a certain threshold, recovery can become almost impossible - unless a sinking fund has been built up over time to pay for total refurbishment…

E.g. Condition Index < 20%


A word of cautionA word of caution……

E.g. Condition Index < 20%

Applies particularly to

static assets – they’re

more easily ‘forgotten’

Ignored!

Buildings, structures, above and underground

pipework systems, transport networks, etc

When the average conditionof the asset population drops below a certain threshold, recovery can become almost impossible - unless a sinking fund has been built up over time to pay for total refurbishment…


Some interesting but disturbing information…

Highways, bridges, rail networks, water supply & wastewater systems, etc

Before the late 1990s, no comprehensive inspection of infrastructure assetshad been carried out in the UK or USA – maintenance of these essential assets, on which a functioning society depended, was fundamentally reactive!


In the UK, the current high rail fares, service disruptionsand all too frequent disasters can be seen as a direct result of failure to maintain assets in a fit for purpose state. The situation with domestic water and wastewater systems is

similar - current service charges are sky high as a

result of past neglect. Maintenance and fitness for

purpose decisions were ignored until crisis point

Some interesting but disturbing information…

Before the late 1990s, no comprehensive inspection of infrastructure assetshad been carried out in the UK or USA – maintenance of these essential assets, on which a functioning society depended, was fundamentally reactive!


Defect discovery & repairDefect discovery & repairThe equipment inspection process The equipment inspection process --control point inspectioncontrol point inspection……


Control point inspection processControl point inspection processInspect

control point 1Inspect

control point 2 continue …

Defect?

Dangerto safety?

Repair in < 10 min?

YES

YESAdvise user/owner

(stop/limit use)

NO

NO

YESRepairdefect

Raise repair Work Order

NO

Reset inspection

interval (+/-)

YES

NO

Call for 2nd Opinion

(now or later)

Temporaryrepair?

YES

YES

NO

YES

inspection interval OK?

UNSURE

Suggest actionto prevent recurrence

(optional)





Defect?

Dangerto safety?

Repair in < 10 min?

YES


(stop/limit use)

NO

NO

YESRepairdefect


NO

Reset inspection

interval (+/-)

YES

NO


(now or later)

Temporaryrepair?

YES

YES

NO

YES


UNSURE


(optional)

Concentrate on defect discovery

not repair!





Defect?

Dangerto safety?

Repair in < 10 min?

YES


(stop/limit use)

NO

NO

YESRepairdefect


NO

Reset inspection

interval (+/-)

YES

NO


(now or later)

Temporaryrepair?

YES

YES

NO

YES


UNSURE


(optional)

Continually review the periodicity of

inspections





Defect?

Dangerto safety?

Repair in < 10 min?

YES


(stop/limit use)

NO

NO

YESRepairdefect


NO

Reset inspection

interval (+/-)

YES

NO


(now or later)

Temporaryrepair?

YES

YES

NO

YES


UNSURE


1. Confirm or alter current inspection interval

2. Call for early re-inspection, as required

(optional)


Compiling inspection plans Compiling inspection plans -- ‘‘routesroutes’’What to do…

List the items of equipment to be inspected List the items of equipment to be inspected –– the most critical & the most critical & significant items firstsignificant items first

Identify the equipmentIdentify the equipment’’s maintenance demanding parts (inspection s maintenance demanding parts (inspection control points), their credible failure modes, how distress wilcontrol points), their credible failure modes, how distress will be l be signalled and the means/technique of detecting distresssignalled and the means/technique of detecting distress

Establish condition acceptance criteriaEstablish condition acceptance criteria

Decide the periodicity of inspection of each control point Decide the periodicity of inspection of each control point ––base it onbase it onhalf the estimated Phalf the estimated P--F interval for the chosen inspection techniqueF interval for the chosen inspection technique

Group control points by their frequency of inspectionGroup control points by their frequency of inspection

Rationalise the inspection frequencies (shift, day, week, month,Rationalise the inspection frequencies (shift, day, week, month,quarter, etc)quarter, etc)

Sequence the items of equipment & control points in logical ordeSequence the items of equipment & control points in logical order r according to the most efficient according to the most efficient ‘‘walking routewalking route’’ around the around the area/facilityarea/facility


The PM inspectorThe PM inspector……

Appoint the most knowledgeable maintenance staff Appoint the most knowledgeable maintenance staff as inspectorsas inspectors

The inspector should report to the maintenance The inspector should report to the maintenance manager or planner manager or planner –– NOT a supervisor who is NOT a supervisor who is oriented towards reactive maintenance oriented towards reactive maintenance

Rotate inspection responsibility around the team to Rotate inspection responsibility around the team to assist PM programme assist PM programme ‘‘buy inbuy in’’

Discourage the repair of defects during an Discourage the repair of defects during an inspection round inspection round –– only minor adjustments should only minor adjustments should be allowedbe allowed


Get started quicklyGet started quickly……DONDON’’T DELAY T DELAY –– JUST GET ON WITH IT! JUST GET ON WITH IT! DonDon’’t fall t fall into the trap of analysis paralysis into the trap of analysis paralysis –– often a problem with often a problem with RCM!RCM!

Build the programme as you go along. You can let the Build the programme as you go along. You can let the PM inspectors decide on the equipment control points PM inspectors decide on the equipment control points to be monitored and their condition acceptance criteria to be monitored and their condition acceptance criteria

Consider a Consider a pilot initiativepilot initiative in a particular area in a particular area –– one one with recurrent failures and poor performance where you with recurrent failures and poor performance where you can gain early, high profile success & win confidencecan gain early, high profile success & win confidence

Strive to get management on side Strive to get management on side –– gain their gain their cooperation cooperation but donbut don’’t depend on having their t depend on having their enthusiastic support to make a start. They will likely enthusiastic support to make a start. They will likely reserve judgement until you demonstrate successreserve judgement until you demonstrate success


Inspection access, aids & housekeepingInspection access, aids & housekeeping……AccessAccess -- Inspectors should have easy and safe access Inspectors should have easy and safe access to inspection control points to ensure inspection quality to inspection control points to ensure inspection quality (so should operators for basic care tasks). Additional (so should operators for basic care tasks). Additional facilities may be necessaryfacilities may be necessary

Inspection aidsInspection aids -- Provide full aids Provide full aids –– inspection inspection mirrors, intrascope, digital thermometer, bearing mirrors, intrascope, digital thermometer, bearing vibration/shock pulse instruments, stroboscope, crack vibration/shock pulse instruments, stroboscope, crack detection, ultrasonic leak detector, etc detection, ultrasonic leak detector, etc –– dondon’’t skimpt skimp

CleanlinessCleanliness -- Clean the equipment before inspection Clean the equipment before inspection --remove dirt & contamination obscuring inspection control remove dirt & contamination obscuring inspection control points and masking distress. Itpoints and masking distress. It’’s best to institute a 5S s best to institute a 5S programme along with PM inspectionprogramme along with PM inspection


Inspection report formInspection report form

Inspection Route: Effluent Plant Frequency: 2 Weekly

Item Control Point Condition Action Required by

Clarifier pump Shaft gland Leak Repack 15/08

Air blower 1 Vee-belt Slack Tighten 03/08

Air blower 2 Pressure gauge Sticking Repair 15/08

Scum scraper Scraper chain Worn Reinspect 07/08

Sump pump 2 Coupling bushes Worn Check & renew 21/08

Effluent pump 1 Lube oil Contamination Renew. Check seal 03/08

Effluent pump 2 Motor Vibration Alignment 15/08

Sludge pump Thermocouple Broken Repair. Guard wire 03/08

Safety shower 1 Thermal insulation Damaged Repair. Check tracing 15/10














Aim for 6 to 10 actionable items per inspection – to assure programme

value & inspector motivation. Continuously review & optimise the

frequency of inspection of each control point accordingly

Repairs or reinspectionsRepairs or

reinspections














The inspector should judge and advise on the required timing of

defect correction or re-inspection so as to avoid operational failure

and high cost of repair














This is a safety critical defect - but corrective

repair needn’t be made for months


Equipment defectsEquipment defects


A chocolate bar foil wrapper – a mechanism-intensive

‘end of line’ machine


Defects

3

For example…



Defects

‘Red tagging’ of defects as they are noted is an

excellent initiativeDEFECTDEFECT

When operations or maintenance staff ‘red tag’ a defect, the tag is not removed until the

defect is repaired

Good tip!



There may be tens of ‘end of line’ machines among hundreds,

or even thousands, of primary and secondary process items of

maintainable equipment…



There may be tens of ‘end of line’ machines among hundreds,

or even thousands, of primary and secondary process items of

maintainable equipment…

The defects present in the total asset

population mount up!


Defects Defects –– total asset populationtotal asset populationDefects requiring corrective repair…

Work Order

You may be ‘aware’ of many defects – and

even have Work Orders for their correction…

BUT what about the defects that haven’t yet been discovered

and recorded


The corrective maintenance backlogThe corrective maintenance backlogDefects requiring corrective repair…

…what about these


The true corrective maintenance backlogThe true corrective maintenance backlogDefects requiring corrective repair…

Administrative backlog

True corrective maintenance

backlog

Most of the repairable defects in a facility remain

unrecorded!




Defects = Latent FailuresDefects = Latent Failures


backlog






backlog

‘partial failures’ compromise OEE or service delivery

capability

+ + activeactive partial failurespartial failures


The true corrective maintenance backlogThe true corrective maintenance backlog



backlog


Many defects will emerge suddenly

as…





backlog

BREAKDOWNS!

ActiveActiveFunctionalFunctional

FailuresFailuresDefects = Latent FailuresDefects = Latent Failures



The DICTATED response – emergency repair!



backlog


ActiveActiveFunctionalFunctional

FailuresFailures





backlog

Identify and correct the most significant defects – OR ELSE HAVE CONTINUING BREAKDOWNS &

CHAOS!



All the defects present should be DISCOVERED, RECORDED & PRIORITISED by carrying out baseline & on-going inspection



backlog





backlog Careful baseline inspection & repair

prioritisation is crucial





backlog

Condition inspection is a ‘work discovery’

process - the recorded workload

will rise initially





backlog

Condition inspection is a ‘work discovery’

process - the recorded workload

will rise initially

The potentially show-stopping defects MUST be repaired. Additional overtime and contract labour

may well be needed for a short time - but the business gains will greatly exceed the expense. Most repair resource must be clawed back

from improvements in planning & scheduling





backlog

Maintenance can be deferred but never avoided! The longer a defect repair

job is left, the more expensive it gets & the

higher the risk!


The corrective Work Order processThe corrective Work Order process……


Work order cycle up to job launchWork order cycle up to job launch

Job planning

Job filtering & approval

Job allocation& launch

Job scheduling

Defect discovery & job origination

The PM inspection report is fed into the normal Work Order process


Work order cycle up to job launchWork order cycle up to job launch

Job planning



Job scheduling


1. Specify job objective (symptoms/real problem)2. Verify acceptability & legality3. Verify affordability4. Prioritise job (seriousness, urgency, growth)5. Approve for planning & scheduling, or reject

1. Analyse work - identify constituent tasks2. Decide task sequence3. Establish resource needs - labour, materials,

special tools, technical files, etc4. Estimate manhours & costs5. Decide work permits needed6. Define special procedures

1. Assign jobs to worker/crew 1 shift in advance2. Activate Work Permit(s)

1. Maintain a 3 to 6 week forward schedule of jobs 2. Prepare detailed schedule for upcoming week in

agreement with operations (pick priority jobs) 3. Optimise resource use (Inter-relational

programming with other jobs)4. Issue weekly schedule (assign trades/teams,

decide date and time of launch for each job)

Some steps are critical to PM programme

success


Most critical steps in the work order cycleMost critical steps in the work order cycle

Prioritise each defect repair job (seriousness, urgency, growth)

Assign jobs to worker/crew 1 shift in advance

Issue weekly schedule of jobs (assign trades, date and time of launch)

Job planning



Job scheduling


The schedule is jointly agreed between the

operations and maintenance groups


Most critical steps in the work order cycleMost critical steps in the work order cycle

Prioritise each defect repair job (seriousness, urgency, growth)

Assign jobs to worker/crew 1 shift in advance

Issue weekly schedule of jobs (assign trades, date and time of launch)

Job planning



Job scheduling


Administrative delays are eliminated and the quality of the completed job is better assured -the worker can mentally plan the next shift, parts, tools, permits,

etc can be prearranged


Reactive work Reactive work No formal job planning & scheduling –manpower demand is excessive…

Manhour DemandThe ‘normal’ time

manhours available

overtime

No planning & scheduling - jobs

done as requested & in response to

failure

No job plan & schedule

Week 1 Week 2 Week 3

When there’s no forward plan, jobs tend to be taken as they come. Low priority jobs are completed whilst serious defects remain unattended to – this results in

continuing disruptive failures and high rates of overtime


Planned workPlanned workFormal job planning & scheduling –manpower demand is contained by ‘smoothing’…


Manhour Demand

Jobs are prioritised & low priority work

deferred

Overtime slashed




Manhour Demand

Jobs are prioritised & low priority work

deferred

Risk based assessment of defect repair priority

channels scarce resources to significant defects on

critical equipment & away from lower risk equipment




The corrective repair schedule should extend

from 3 to 6 weeksManhour Demand




Manhour Demand Manhours ‘liberated’become available for

other work, and…




Manhour Demand

rightly so!

…by pushing forward the planning horizon, some

jobs will never be done –they’re just dumped…


Planning & schedulingPlanning & scheduling

Planning need not be time Planning need not be time consuming consuming –– allow 5% of available allow 5% of available manhours if youmanhours if you’’re good at it, 10% re good at it, 10% when youwhen you’’re a novicere a novice

Initially the time to plan must be Initially the time to plan must be ‘‘foundfound’’. With more order in the . With more order in the workplace, the savings made will workplace, the savings made will offset planning timeoffset planning time

Many jobs need only minimal Many jobs need only minimal planning planning –– no spare parts, one no spare parts, one trade. These just need to be trade. These just need to be prioritised correctlyprioritised correctly

Maintenance

Manager


HOWEVER HOWEVER -- maintenance is datamaintenance is data--drivendriven

A move to PM is a move to data management & paperwork!

ItIt’’s 90% information & 10% engineerings 90% information & 10% engineering……

Maintenance

Manager


Maintenance is dataMaintenance is data--drivendriven

A move to PM is a move to data management & paperwork!

Maintenance

Manager

ItIt’’s 90% information & 10% engineerings 90% information & 10% engineering……

You really need a computerised information system with mobile data gathering capability. The ideal is to use an AIDC system

which allows automatic identification of equipment and control points using, bar codes,

or RFID tags - according to individual needs

Automatic Identification &DataCollection


To conclude…


Another conundrumAnother conundrum……

Fact Despite its crucial importance, the majority of asset-intensive organisations don’t have a programme of systematic inspection (surveillance) of their equipment

Query What’s the problem?



Despite its crucial importance, the majority of asset-intensive organisations don’t have a programme of systematic inspection (surveillance) of their equipment

Fact

Query What’s the problem?

Sad answer A fundamental lack of:……………………………………………………………………………………………………

Stop thinking and GET ON

with it!

(Complete according to view!)


Despite its crucial importance, the majority of asset-intensive organisations don’t have a programme of systematic inspection (surveillance) of their equipment


Fact

I suppose I’d better make a start…

Query

Sad answer A fundamental lack of:……………………………………………………………………………………………………

What’s the problem?

(Complete according to view!)


The winning formulaThe winning formula……

BC + CI + DP + RS = P + S

basic

care

cond

ition i

nspe

ction

defec

t prio

ritisa

tion

repair

sche

dulin

gPROFITSAFETY

LubricationAdjustmentCleaning


Main pointsMain points……Reactive maintenance can easily double the cost of maintenance Reactive maintenance can easily double the cost of maintenance labour and materialslabour and materialsThe adverse consequences of nonThe adverse consequences of non--compliant equipment conditions compliant equipment conditions and sudden failures are almost without limit and sudden failures are almost without limit –– the severity of an the severity of an untoward event is just a matter of luckuntoward event is just a matter of luckEquipment problems are predominantly selfEquipment problems are predominantly self--inflictedinflictedProposals to resolve equipment problems by increasing the Proposals to resolve equipment problems by increasing the maintenance budget will rightly be resisted maintenance budget will rightly be resisted -- the manhours needed the manhours needed must be freed up from work planning and efficiency improvementsmust be freed up from work planning and efficiency improvementsCommitment and persistence alone are needed to change to better Commitment and persistence alone are needed to change to better organisation, reduced costs and higher equipment reliabilityorganisation, reduced costs and higher equipment reliabilityManagement cooperation is needed to introduce an inspection Management cooperation is needed to introduce an inspection programme, but full support will only be forthcoming when they sprogramme, but full support will only be forthcoming when they see ee what success looks likewhat success looks likeStrive to implement other initiatives to support the inspection Strive to implement other initiatives to support the inspection programme programme –– basic care and 5S, without these the PM inspection basic care and 5S, without these the PM inspection programme may well be underminedprogramme may well be undermined


Thank you!

<End>

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