inspection and testing of quality in TQM

inspection and testing of quality in TQM

1. Unit: 2 Lecture: 12
Dr.JayantaKr.Mahato
Associate Professor
Mechanical Engineering Dept.
ShobhitUniversity, Meerut
Inspection and testing of
quality

2. ®
-:Content:-
•ObjectiveofQuality
•ProcessandInspection
•ProcessTurtlediagram
•ProcessControl
•Inspectionobjectiveand
purpose
•Stagesofinspection
•Methodsofinspection
•Drawbacksofinspection
•QualityCost
•Qualityimprovement

3. ®
-:ObjectiveofQuality
:-(1)Todecideaboutthestandardof
Quality of a product that is easily
acceptabletothecustomer.
(2)Tocheckthevariationduring
manufacturing.
(3)Topreventthepoorquality
productsreachingtothecustomer.

4. ®
-:ProcessandInspection :-
WhatisProcess?
Ans: A series of actionsor steps
takeninordertoachieveaparticular
product.
Whatisaninspection?
Ans:Aninspectionistheverification
of process/product qualityto pre-
identified quality specifications
before, during or after the production
process.
Benefits of inspection: It helps to
control quality, reduces
manufacturingcosts,eliminatescrap
lossesandassignablecausesof
defectivework.

5. ®
-:ProcessTurtle Diagram:-
PROCESS
NAME/DESCRIPTION:
Whatstepsareinvolvedinthe
process?
Whathappensateach stepinthe
process?
Whatdocumentsandrecordsare
generated?
Istheprocessimplementedin
accordance with procedures,
instructionsorplans?
Arecontrolsappliedas described?
PROCESSINPUTS:
Whattriggerstheprocess?
Whatinputsarerequired?
Wheredotheinputscomefrom?
Are they received in a timely
manner?
Aretheyfitforpurpose?
PROCESSOUPUTS:
What is theproductproducedbythis
process?Are product measures in
place to ensure that product meets
requirements? How are processes
measured? Are product and process
measuresachieved?
Whatfeedbackisreceivedfrom
customers?
EQUIPMENT&FACILITIES:
What equipmentandresourcesare
required?
Isequipmentsuitableandproperly
maintained?
Is the work environment maintained?
Is there evidence of appropriate
maintenanceofallequipmentusedby
thisprocess?
INSTRUCTIONS&
PROCEDURES:
Review the documents that
describe and control the process.
Reviewalltheimportantstepsand
activities of the process being
audited. This info must be
documented. Evaluate how
effectively the processflows
throughthesteps.
Do youseeroadblocksorissues?
SUPPORTPROCESSES:
Asyouaudit,youwillseehow it
connects and interacts with other
processes. Interactions with other
processes are always important. Audit the
relevant links to related processes and
supportprocesses.
KEYPERFORMANCE
INDICATORS:
Reviewmetrics andperformancewith
Managers, Supervisors and operators.
They should know how things are
running,objectives,customerissues,
problem areas. If they do not, the
requirements were not met. Is there
evidencethatqualityobjectivesand
targets affected by this process are
beingachieved?
PERSONNEL:
Review employee skill lists for the
process.Are therelistsofskillsforeach
position? Do they show enough detail?
This is often a finding, where lists are
generic with inadequate detail. Training
isa keyprocessofanysystem.Are there
particularskillsyouwant toevaluate?
CONTROLPROCESSES:
Howistheprocessdefinedandwho
is responsible? How are customer
requirements defined? What
specificationsapplydefined?
What objectives and targets apply
process?Whatcontrols/checkpoints
arethere?
What acceptancecriteriaexist?

6. ®
ProcessControl
(6) Taking action, if any, on the
difference.
•ProcessControl:Theprocessthroughwhichthestandardsare
establishedandmetwithstandardsiscalledProcessControl.
Thecontrolprocessinvolvesa
universalsequenceofstepsas
follows:
(1)Choose thecontrolsubjectand
unitof measure.
(2)Setastandardvaluei.e.,specify
thequalitycharacteristics
(3)Chooseasensingdevicewhich
canmeasure.
(4)Measureactualperformance.
(5)Interpret the difference between
actualandstandard.

7. ®
Factors Affecting Quality

8. ®
Factors Affecting Product Design

9. ®
-:Inspection objectivesandPurpose:-
ObjectivesofInspection
(1)Tocollectinformationregarding
the performance of the product
withestablishedstandardsfortheuse
of engineering production,
purchasingandqualitycontroletc.
(2)To sort out poor quality of
manufacturedproductandthusto
maintainstandards.
(3)Toestablishand increasethe
reputationbyprotectingcustomers
from receiving poor quality
products.
(4)Detectsourceof weakness and
failureinthefinishedproducts

10. ®
-:Inspection objectivesandPurpose:-
PurposeofInspection
(1)To distinguish good products
frombadproducts
(2)Todetermineiftheprocessis
changing.
(3)Todetermineiftheprocessis
approachingthespecificationlimits.
(4)Toratequalityofproduct.
(5)Torateaccuracyofinspectors.
(6)Tomeasuretheprecisionof
measuringinstrument.
(7)To secure products –design
information.
(8)Tomeasureprocesscapability.

11. ®
-:Types of Quality Inspection:-
4 types of inspection in quality control:
Pre-production Inspection
During Production Inspection
Pre-shipment Inspectionand
Container Loading/Unloading Inspections

12. ®
-:Types of Quality Inspection:-
Pre-productionInspection:Itisconductedbeforetheproduction
processbeginsandhelpstoassessthequantityandqualityofthe
rawmaterialsandcomponentsandwhethertheyconformtothe
relevantproductspecifications.

13. ®
-:Types of Quality Inspection:-
DuringProductionInspection:Itisaqualitycontrolinspection
conductedwhileproductionisunderway.Thisstepisparticularly
usefulforproductsthatareincontinuousproductionandhave
strictrequirementsand/orwhenqualityissueshavebeenfound
priortomanufacturingduringanearlierPPI

14. ®
-:Types of Quality Inspection:-
Pre-ShipmentInspection:Theseareimportantstepinthequality
controlprocessandthemethodforcheckingthequalityofgoods
beforetheyareshipped.Itensuresthatproductioncomplieswith
thespecificationsofthebuyer.Itisconductedonfinishedproducts
whenatleast80%oftheorderhasbeenpackedforshipping.
Randomsamplesareselectedandinspectedfordefectsagainst
therelevantstandardsandprocedures.

15. ®
-:Types of Quality Inspection:-
ContainerLoading/LoadingSupervision(LS):Itensureyour
productsareloadedandunloadedcorrectly.Inspectorswill
supervisethroughoutthewholeprocessandensureyourproducts
arehandledprofessionallytoguaranteetheirsafearrivaltotheir
finaldestination.

16. ®
-:Types of Quality Inspection:-
Piece-by-PieceInspections:Itinvolvescheckingeachandevery
itemtoevaluatearangeofvariablesincludinggeneralappearance,
workmanship,function,andsafety.Thisinspectionprocesscanbe
carriedouteitherbeforeorafterthepackaginginspection.Inthe
circumstancewherethegoodsrequireparticularattentionto
ensurecompliancetospecificationorwhenthegoodsarehigh-
value,a100%inspectionserviceshouldbeperformed.

17. ®
-:StagesofInspection:-
(1) Inspection of incoming
materials:Itisalsocalledreceiving
inspection. It consists of inspecting
and checkingof all the purchased
raw materials and parts that are
supplied before they are taken on to
stock or used in actual
manufacturing.Inspection
may take place either at supplier’s
endoratmanufacturer’sgate.Ifthe
incoming materials are large in
quantity and involve huge
transportation cost it is economical
to inspect them at the place of
vendororsupplier.

18. ®
-:StagesofInspection:-
(2)Inspection of production process:
The work of inspection is done while
theproduction processis
simultaneouslygoingon.Inspectionis
done at various work centers of men
and machines and at the critical
production points. This is having
advantage of preventing wastage of
time and money on defective units and
preventingdelaysinassembly.
(3)Inspection of finished goods: This
isthelaststagewhen finishedgoodsare
inspected and carried out before
marketingtoseethatpoorquality
productmaybeeitherrejectedorsoldat
reducedprice.

19. ®
1)100%Inspection:
This type will involve careful inspection in
detail of quality at each strategic point or
stage of manufacture where the test involved
is non-destructive and every piece is
separately inspected. It requires more number
ofinspectorsandhenceitisacostlymethod.
Thereisno samplingerror.Thisissubjected
to inspection error arising out of fatigue,
negligence,difficultyofsupervisionetc.
Hencecompleteaccuracyofinfluenceis
seldomlyattained.
Itissuitableonlywhenasmallnumberof
piecesarethereoraveryhighdegreeof
qualityisrequired.Example:Jetengines,
Aircraft,MedicalandScientificequipment.
-:StagesofInspection:-

20. ®
2)SamplingInspection:
Inthismethodrandomlyselectedsamples
areinspected.Samples takenfromdifferent
batches of products are representatives. If
the sample prove defective, the entire
concernedistoberejectedorrecovered.
Sampling inspectionischeaperandquicker.
It requires less number of Inspectors. Its
subjectedtosampling errorsbutthemagnitudeof
sampling error can be estimated. In the case of
destructivetest,randomor sampling
inspection is desirable. This type of inspection
governs for automatic machines which are less
susceptible to chance variable and hence require
lessinspection,suitableforinspectionofproducts
which have less precision importance and are less
costly.
-:StagesofInspection:-

21. ®
-: DrawbacksofInspection:-
(1)Inspectionaddstothecostoftheproduct
butnotforitsvalue.
(2)Itis partiallysubjective,oftentheinspector
has to judgewhetheraproduct passesor not.
Example : Inspector discovering a slight burnish
on a surfacemustdecidewhetheritisbadorit
canfit.
(3)Fatigueand Monotonymayaffectany
inspectionjudgment.
(4)Inspectionmerelyseparatesgoodandbad
items.Itisnowaytopreventtheproduction
of bad items.

22. ®
-: QualityCost :-
(A)Failurecosts:-
1)Internalfailurecosts:-Theyinclude,
a)Scrap:Thenetlossin laborandmaterialresultingfrom
defectiveswhichcannoteconomicallyberepairedorused.
b)Rework:Costofdefectcorrectiontomakethemfitforuse.
c)Retest:The costofinspectionandretestofproductsthat
haveundergonereworkorotherrevision.
d)Downtime:The costofidle facilitiesresultingfromdefects.
(Example:Printingpressdownduetopaperbreak).
e)Yieldlosses:Thecostofprocessyieldlowerthatmightbe
attainablebyimprovedcontrols.Includes‘‘overfill’’ofcontainers
(going to customers) due to variability in filling and measuring
equipment.

23. ®
-:QualityCost:-
2)Externalfailurecosts:-Theyincludes,
a)Complaint adjustment : All costs of
investigation and adjustment of justified
complaintsattributabletodefectiveproduct
orinstallation.
b)Returnedmaterial:Allcostsassociated
withreceiptsand returnedfromthefield.
c)Warrantycharges:Allcostsinvolvedin
service to customers under warranty
contracts.
d)Allowances:Costs ofconcessionsmade
to customers due to substandard products
being accepted by the customer as is include
lossinincomeduetodowngradingproducts
forsaleasseconds.

24. ®
-: QualityCost :-
(B)AppraisalCosts:Thesecostsinclude,
a)Incomingmaterialinspection:Thecost of
determiningthequalityofvendor/suppliermade
productsbyinspectionon receiptorat source.
b)Inspectionand test:Thecostofcheckingthe
conformance of the productthroughout its
progression,inthefactory,including finalacceptance
and checkof packing.Alsoincludestestingdoneat
customer’spremisespriorto giving up theproductto
thecustomer.
c)Maintainingaccuracyoftestequipment:Includes
the costofoperatingthesystemthatkeeps the
measuringinstrumentsandequipmentincalibration.
d)Materials andservicesconsumed:Includescosts
ofproductconsumedthroughdestructive tests,
materialsconsumedandserviceswheresignificant.
e)Evaluationofstock:Include thecostsoftesting
productsinfieldstorageorinstockto evaluate
degradation.

25. ®
-: QualityCost:-
(C)PreventionCosts:Itincludes:
a)Quality Planning:Thisincludesthebroadarray of
activitieswhichcollectivelycreatequality plan,the
inspection plan, reliabilityplan,datasystemand
numericspecializedplans. Itincludes alsopreparation
of themanualsand proceduresneededtocommunicate
theseplanstoall concerned.
b)New Product review:Includespreparationofbid
proposalsevaluationof newdesign,preparationoftest
and experimentprogramsandotherquality activities
associatedwiththelaunchingofnew designs.
c)Training:Thecostsofpreparingtrainingprograms
forattainingand improvingqualityperformance
includesthe costofconductingformaltraining
programsaswell.
d)Process control: Includes that part of process
controlwhichis conductedtoachievefitnessforuseas
distinguishedfromachievingproductivity,safetyetc.

26. ®
-:QualityImprovement:-