Presented by:

Abhilasha Singh

Bhushan Salunke

Chetan Shah

Chanchal Gupta

Ruchi Shukla

Jagjit Singh Panesar

CONTENTS

INTRODUCTION

WHAT IS ERROR ?

POKA YOKE OVER ERRORS

IMPORTANCE

WHEN TO USE

HOW TO USE

METHODS

DAY 2 DAY EXAMPLES

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WHAT IS POKA YOKE ???3

a) Brother of PIKACHU

b) A new Chinese action hero

c) A diseaseIt’s a mistake proofing technique used by each of us

Pronunciation POH-KAH-YOH-KAY

YOKERU Avoid

POKA Mistakes

Coined in Japan during the 1960s by

as part of the Toyota Production System

INTRODUCTION4

Shigeo Shingo

Initially ‘BAKA-YOKE’ ‘fool-

proofing’

Dishonorable and offensive

Changed to ‘POKA-YOKE’ ‘mistake-

proofing’

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INTRODUCTION (Cont.)

WHAT IS ERROR ???

A mistake : deviation from what is correct, right, or true

How to prevent error

Old way Scold peopleRetrain them Tell them to be more careful…

New way Training and motivationEasy way to do a job

The potential for human error can be dramatically reduced

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What Causes Defects?

Errors lead to defects

1. Poor procedures or standards

2. Machines

3. Non-conforming material

4. Worn tooling

5. Human Mistakes

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Help operators avoid mistakes in their work caused by

choosing the wrong part, leaving out a part, installing a part

backwards, etc.

Involves the implementation of fail-safe ways methods that

detect or prevent human and machine error at or near the

source.

Provides instant feedback and prevention of quality problems

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Poka Yoke over Errors

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Poka-Yoke as a…

Poka Yoke as Prevention Device:

Examples: part locators, part present sensors.

Poka Yoke as Detection Device:

Examples: vision system, limit sensors

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Why is it important?

Helps people and processes

Refers to techniques that make it impossible to

make mistakes.

Helps drive defects out of products and processes

and substantially improve quality and reliability.

Thought of as an extension of FMEA.

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Contd…

Used to fine tune improvements and process

designs from six-sigma.

Use the ideas and methods in product and

process design which can eliminate both human

and mechanical errors.

When to use it?

It is a technique, a tool that can be applied to any

type of process be it in manufacturing or the

service industry.

Poka-yoke can be used wherever something can

go wrong or an error can be made.

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Contd…

Errors can be of any type-

i. Processing Error: Process operation missed or not performed per the SOP.

ii. Setup Error: Using the wrong tooling or setting machine adjustments incorrectly. 

iii. Missing Part: Not all parts included in the assembly, welding, or other processes.

iv. Improper part/item: Wrong part used in the process.

v. Operations Error: Carrying out an operation incorrectly; having the incorrect version of the specification.

vi. Measurement Error: Errors in machine adjustment, test measurement or dimensions of a part coming in from a supplier.  

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How to use it?

Step by step process in applying poka-yoke:

1. Identify the operation or process

2. Analyze the 5-Ws and understand the ways a process can

fail.

3. Decide the right Poka-yoke approach, such as using a,

Shut out Type: Preventing an error being made, or an

Attention Type: Highlighting that an error has been

made.

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Contd…

4. Determine whether a

Contact Method

Constant Number or Counting Method

Motion-Sequence Method

5. Trial the method and see if it works.

6. Train the operator, review performance and

measure success.

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Methods in Detail

Contact Methods:-

“Do not have to be high tech!”

These can be as simple as blocks that do not allow parts to be seated in the wrong position prior to processing.

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Methods in Detail

Take advantage of parts designed with an uneven shape.

This method signals to the operator right away that the part is not in proper position.

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Methods in Detail

Constant Number or Counting Method:-

Used when a fixed number of operations are required within a process.

When a product has a fixed number of parts that are attached to it.

A sensor counts the number of times a part is used or a process is completed and releases the part only when the right count is reached.

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Methods in Detail

Motion-Sequence Method:-

The third poka yoke method uses sensors to determine if a motion or a step in a process has occurred.

If the step has not occurred or has occurred out of sequence, the sensor signals a timer or other device to stop the machine and signal the operator.

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Day 2 Day Examples of Poka-Yoke

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Disk

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File cabinets, opening one drawer locks all the rest,

reducing the chance of the file cabinet tipping.

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Sinks

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Microwaves

Washing machines

Central locking in modern cars

Key locks in mobiles

Refrigerators

Beeps in automobiles if key is left in ignition

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Okay, So This Is Not An Everyday Example For

Anybody. I Hope You'll Find It Interesting …

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Submarine

The bathyscaph is a deep water submarine used to explore the very lowest parts of the ocean. It is electrically powered. Once at the bottom, if the batteries or electrical system fail the best outcome would be for the sub to return to the surface. The designers made this outcome occur by holding the ballast in place with electromagnets. When power is lost, the ballast drops off automatically and the sub starts its ascent.

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Characteristics of PokaYoke devices

Simple and cheap

Part of the process, permitting 100% inspection

Placed close to where the mistakes occur,

providing quick feedback

Designed to stop a particular mistake

A detection device cannot provide a complete

error proof solution

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TO ERR IS HUMAN NATURE

BUT

INTELLIGENCE IS ALSO HUMANNATURE

SO

NEVER STOP FINDING WAYS OFNOT MAKING MISTAKES

REMEMBER

Thanks For Keeping Patience

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