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Part Production

Communication

PART PRODUCTION COMMUNICATION MODEL

MANAGEMENT

DESIGN

TOOLING

PRODUCTION

INSPECTION

ASSEMBLY

ROUTING

PLANNING

PRICING

SERVICE

PURCHASING

SALES

CUSTOMERS

VEND

ORS

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IMPORTANCE OF

INSPECTION In quality control, inspection is the means

by which poor quality is detected andgood quality is assured

Traditional method to inspect after theprocess may cause time delay and extracost

The cost is due to rework and defective

part that have to be scrapped

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New approaches in

inspection

100% automated inspectionOn-line sensor systemduring/immediately after process

Feedback control on the processitself

Mechanism to track and analyze

the measurements

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Inspection Fundamental Refers to the activity of examining the

product or part or material To determine whether they conform to

design specifications

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ass ca ons oInspection

Inspection for variables- Measurements using appropriate

measuring equipment

Inspection for attributes- Part/product is inspected to determine

whether it conforms to the accepted

quality standard

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Examples (Inspection for

Variables)

Measuring dia of a cylindrical part Measuring the temperature Measuring the electrical resistance

Measuring the specific gravity of a fluidchemical product

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Example (Inspection by

Attributes)

Gaging a part with GO/NO GO gauge todetermine if it is within tolerance

Determine the defect rate of a sample of

production parts Counting the no. of defects per car Counting the no. of imperfections in a

production run

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Comparison of Inspection

For Variables For Attributes

More information (quantitativevalue) is obtained

Only to know whether the part isacceptable or not (G/NG)

Quality characteristics data canbe collected over time to observethe trend

Quantity data can be collectedover time to observe the trend

More time is required Done quickly and less time isrequired

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Inspection Procedure Presentationthe item is presented for

examination Examinationcheck for nonconforming

features Decisionjudgement whether to accept

or not Actionaccept/reject/sorting/rectify

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Inspect ion method

1) Manual Inspection

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Inspect ion method2) Automated Inspection The inspection is done by 100% screening or

sampling Time consuming & costly inspection can be

minimized by checking on the keycharacteristics or the critical point of dimensions

CMM automated inspection

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Testing

Testing refers to assessment of thefunctional aspects of the product.

QC Testing is a procedure in which the

item being tested is observed during actualoperation

2 types1) Destructive Testing (DT)2) Nondestructive Testing (NDT)

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en an ere oInspect

Receiving Inspection (Incoming) During the manufacturing (Production) Before delivery (Outgoing)

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Inspection Techniques -Categories

Contact

- Physical contact is made

between the object andinstrument

Non-contact- No physical contact is made

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CONTACT INSPECTION Widely used in manufacturing To obtain physical dimensions of the part Typically use mechanical probe or other

device that enable contact with the object

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P i i l C t t

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Principal Contact

Inspection Technologies

Conventional and gauging instruments1) Manual2) Automated

Coordinate measuring machines (CMM) Stylus type surface texture measuring

machines

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u a y ase on par svariety & quantity

DirectComputerControlled

CMMsMotor-drivenand manualCMMs

Flexible inspectionsystems

Manualmeasurementand gauging

Manual and semi-automaticmeasurement andgauging

Dedicationautomaticmeasurement,machine vision

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Parts

Variety

PartsQuantity

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inspect ion method is

impor tant

Most widely used inspection technologies Accurate and reliable In many cases, they represent the only

methods available to accomplishinspection

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