Presented To;CUMI-Bonded

Presented By:E&T

Why Why Benjamin Franklin's 5-Why Analysis: For want of a nail a shoe was lost, for want of a shoe a horse was lost, for want of a horse a rider was lost, for want of a rider an army was lost, for want of an army a battle was lost, for want of a battle the war was lost, for want of the war the kingdom was and all for the want of a little horseshoe nail. lost,

OVERVIEW OF DEFECT/FAILURE Dr JURAN STATED THE FOLLOWING IN HIS MORDERN QUALITY MANAGEMENT(JUSE) DEFECTS/FAILURES ARE CLASSIFIED INTO : SPORADIC CHRONIC

OVERVIEW OF DEFECT/FAILURESPORADIC DEFECT : Undesirable changes that occur in the present state Requiring treatment designed toRestorethe present state (exchange of jigs that have worn off) Thinking that present state should be maintained

OVERVIEW OF DEFECT/FAILURE CHRONIC Defects Continued undesirable state , REQUIRING Treatment that changes the presentstate and Thinking to break through the current state

Types of LossesLosses

Sporadic Losses

Chronic Losses

Due to specific and Assignable causes

Due to common and unassignable causes

Infrequent Larger Magnitude Recognizable Easy methods of analysis Definitive countermeasures

Single cause One of several causes Combination of several causes Frequent Smaller magnitude Difficult to understand

WHEN TO USE WHY WHY ANALYSIS It is an analytical tool used for identifying single assignable cause leading to defect / breakdown/ loss.

BREAKDOWN CAUSES

NAKANO SAN HAS COMPILED IN HIS PLANNED MAINTENANCE BOOK THE FACTORS FOR FAILURE

Analysis of Stress and StrengthThree major causes Factors of failure 1 Neglected Deterioration Inadequate compliance with basic requirements Cleaning, Oiling and tightening are not carried out properly. Strength analysis Operators perform routine maintenance improperly or not at all. Neglected deterioration Safety margin Detection of natural and accelerated deterioration and proper restoration Failure : a are neglected. In other words, inspection, examination and preventive repair to correctly restore the equipment are not carried out. Time Indifferent / no awareness to the stress 2 Uncontrolled stress Non-compliance with usage requirements Equipment and machinery posses operating limitations based on design considerations. Sometimes these are ignored. Failure : b Example: Current, Voltage,RPM, Velocity, Temperature etc. Lack of skill Repair error by maintenance personnel or operators. Equipment Time operation error (Parts replacement error, operation without license) Inherent design weaknesses Insufficient strength can be inherent due to poor design, fabrication and installation caused by lack of engineering skills or error.Stress and strength

3 Insufficient StrengthStress and strength

Stress and strength

Failure : c Time

15

Subdivision of Failure Factors FOR MACHINES

Uncontrolled stress

Inadequate compliance with basic requirements Neglected deterioration

Neglected deterioration

Non-compliance with usage requirements Lack of skill

Insufficient strength

Inherent Design weaknesses

16

Five Countermeasures to Achieve Zero Failures

Five Factors1

Five Countermeasures1

Inadequate compliance with basic requirements

Adequate compliance with basic requirements Compliance with usage requirements Restoration of deteriorated equipment condition Rectification of design weaknesses Improvement of operation and maintenance skills

2

Non-compliance with usage requirementsNeglected deterioration Inherent design weaknesses Lack of skill

2

3 3

4

4

5 5

18

Fig.1.6 Procedures to Achieve Zero Failure Failure analysis of stress and strength1.Abnormal stress that exceeds the equipment strength is applied (Uncontrolled stress) 2.The equipment strength weakness to the extent that it is unable to bear stress during operation (neglected Deterioration) 3.The equipment inherently possesses weaknesses created during design and fabrication of the equipment (insufficient strength)

Failure analysis Factor analysis

Five countermeasure to achieve zero failure 1.Adequate compliance with basic requirements 2.Compliance with usage requirements 3.Restoration of deteriorated equipment condition 4.Rectification of design weakness 5.Improvement of operation and maintenance skills Five phases to achieve zero failures1. Eliminate the causes of accelerated deterioration and carry out restoration and improvement of equipment conditions

Concept level

Approach analysis

2. Extend inherent service-life of the equipment 3. Research natural deterioration process 4. Search for deterioration parameters 5. Implement predictive maintenance

Concrete zero failure activities

Build the Jishu-Hozen system Seven Steps to Jishu-Hozen 1.Initial cleaning 2.Countermeasures against contamination sources and areas with difficult access 3. Tentative cleaning and oiling standard procedure 4. Total inspection 5. Autonomous inspection 6. Standardisation 7. Autonomous management

Build the maintenance system

Seven steps to Keikaku-Hozen 1.Analysis of present status 2.Restoration and improvement of the deteriorated equipment condition 3. Tentative standard maintenance procedure 4. Overall inspection of quality function 5. Improvement of inspection and maintenance efficiency 6. Execution of predictive maintenance 7. Horizontal replication

Activity level

20

REACTIVE ZERO IN DEFECT/BREAKDOWN IN ORDER TO ACHIVE AND SUSTAIN TPM TARGET OF ZERO DEFECT AND BREAKDOWN , EVERY FAILURE IS ANALYSED TO PREVENT THE RECURRENCE OF THE PHENOMENON There by achieving ZERO defect/breakdown

why why approach for Machine breakdown

WHERE TO DO WHY WHY ANALYSIS

IN TPM ACTIVITIES , GREAT IMPORTANCE IS ATTACHED TO THE THREE ACTUALITIES

WHERE TO DO WHY WHY ANALYSISACTUAL LOCATION-Where the actual process is taking place/ machine location ACTUAL OBJECT-With the defective product/ machine part ACTUAL PHENOMENON-Details of how the problem manifested( Provide the best clues for locating their sources)

HOW TO CONDUCT FAILURE ANALYSIS CLARIFICATION OF PHENOMENAimmediately after occurrence of failure Check the state of stoppage The kind of malfunctioning part Time of last failure Ask operator any pre-stoppage symptoms

How to conduct failure analysis TEMPORARY STEP REPLACE PARTS THIS IS NOT COUNTERMEASURE BUT A NATURAL STEP

PREPARATION FOR THE INVESTIGATION OF CAUSE It is necessary to understand the function, structure, proper operating method, using illustrations or system diagrams of equipment and part pertaining to the failure

HOW TO CONDUCT FAILURE ANALYSIS PREPARATION FOR THE INVESTIGATION OF CAUSE Knowledge & Understanding the desirable conditions of functional parts as seen from engineering principles, rules, and inspection of equipment from viewpoint of weather necessary and sufficient conditions are satisfied. It is important to thoroughly examine listed inspection items and identify malfunction

Pursuit of Causes Use why why analysis Understand equipment mechanism, details of malfunctions and the method of inspection Promote understanding through the so called set of 3 items Broken parts Analysis document and one point lessons

WHY WHY ANALYSIS ACTION SIDE1. Problem Phenomena 2. What is the final action taken. After taking action is it yield result Yes / No If Yes 3. Why 1. Why the action is taken Investigation/Confirmation Before countermeasure Photo

Investigation/Confirmation

Why ?Investigation/Confirmation

4. Why 2. Why did "why 1" occur ?Why ? 5. Why 3. Why did "why 2" occur ? Let us do this 6. countermeasure Investigation/Counfirmation

After Countermeasure

Photo

Why Why Analysis Report From Action Side

Problem description Final action taken to make the thing OK After countermeasure is problem eliminated

Spots gets shifted during the operation time Electrode alignment corrected Yes

Date and time of the countermeasure WHY why alignment corrected why electrodes are not Co-axial why play observed between key and piston rod why wear of piston and key ANSWER electrodes are not Co-axial play observed between key and piston rod wear of piston and key ACTION TAKEN Alignment Corrected Screw tightened key replaced and piston rod grinded

Why 1 Why 2 Why 3

Why 4 Why 5

natural deterioration

To be check and adjusted during the PM

Root cause: natural deterioration Root cause is one of the following five items 1 Poor condition 2 Poor operating condition 3 deterioration 4 week design 5 poor skill JH PM Design E&T

Why Why AnalysisExample 1Cylinder Does Not Operate Smoothly Question What is Your Final Action After Cleaning Strainer, Is it OK WHY Why did you clean strainer Why Strainer was Clogged Why Oil was Dirty Why does dirt get in Why was hole made Answer Cleaning Strainer Yes ANSWER Strainer was clogged Oil was Dirty Dirt entered the tank upper plate of tank has hole and gap Repair error during maintenance work Clean Strainer Drain Oil and Clean Prevent Scattering of chips and cutting fluid Plug hole and gap Standardise repairs

ACTION

Example 2Oil leaks from cylinder rod each time it operates Question What is Your Final Action After replacing the o-ring is it OK? WHY Why did you replace o-ring Why o-ring out? why rod has scratch o-ring cut rod has scratch chips were scattered and attached to rod Cylinder located within scattering range of chips and rod cover is not plaed Replacing the o-ring Yes ANSWER Answer

ACTION o-ring changed scratch removed measures taken to prevent chips from scattering cyliners position changed and cover fixed standard design and installation

Why chips were attached on rod Why cylinder located within scatterign range of chips and rod cover not replaced defective design and installation

A Sample Why-Why AnalysisCylinder does not operate smoothly Final action taken: Cleaned the strainer Is it OK, now? Yes

Why? Why did you clean strainer?

Reason

Action required

Strainer was clogged

Clean strainer

Why was strainer clogged?

Oil was dirty

Drain oil and clean

Why was oil dirty?

Dirt entered the tank

Stop contamination

Why did dirt enter tank?

A hole and gap in the lid

Plug the hole and gap

Why there is a hole / gap?

Mistake while repairing

Standardize repairs

COUNTERMEASURES FOR BD-WHY WHY TO BE RECURRENCE PREVENTION KAIZEN POSITIVE INDIACTION SYSTEM JH/PM CHECK STANDARD DESIGN IMPROVEMENT TRAINING

REACTIVE APPROACH FOR ZERO DEFECT

SETTING CONDITIONS FOR ZERO DEFECTCaused by raw material conditions Producing materials and energy not to generate defects Quality Defect Factors Caused by equipment Caused by method precision conditions Caused by conditions of people involved Fostering operators proficient in equipment and job

Manufacturing equipment not to generate defect

Devising methods not to generate defects

Quality Assurance +Equipment and environment management

Jishu-Hozen activitiesMaterial Management +Skill Education and Training

Design check

PM Analysis

Pursue relationship between quality characteristics and material and energy condition / equipment precision / method conditions

Set conditions of equipment not to generate defects Management of conditions not to generate defects (Hinshitsu Hozen) Zero quality defects

Maintenance and management ability training (Ability to find cause system troubles and to quickly and correctly take actions)

JIPM, 1987

Ms that decide QualityManufacturing specification MachineOptimal conditio n setting Equipment Jigs, tools Measuring devices

MaterialMaterials Prior-Process machined parts

MethodMachined conditions Work methods Measuring methods

ManMorale Environment

Work standards Inspection standards Training, observance or work standards

Standardization

Machining

Machined products

Inspect

Inspection standard

Quality assurance

JIPM, 1987

Maintain & control of Quality

Measure, adjust

Quality improvement management

Defects classificationA - Type defectOK

B - Type defectOK

C - Type defectNOT OK

NOT OK

NOT OK

Action taken by operator

No action by operator

OK

Action taken by operator

LSL

OK

USL

LSL

OK

USL

LSL

OK

USL

The output is (OK) initially Becomes (NG) Corrective action is taken by operator Becomes (OK) Use Why Why Analysis

The output is (OK) initially Becomes (NG) No action taken by operator Becomes (OK) Use PM Analysis

The output is (NG) initially Action taken by operator Becomes (OK) (setting scrap)

Understanding quality defect phenomena

Clarity on the definition of the defect Frequency of occurrence and effect of defects

A - Type defect : ExamplesOK

NOT OK

Action taken by operator

OKLSL USL

B - Type defect : ExamplesOK

NOT OK

No action by operator

OKLSL USL

C - Type defect : Examples

NOT OK

OK

Action taken by operator

LSL

OK

USL

WHY WHY PROBLEM SIDEBefore countermeasure WHY ? 2.Why 1 why did the problem '' phenomenon'' occur WHY ? 2.Why 1 why did the '' Why-1'' occur?

1. Problem Phenomena

pho to

INVISTIGATION/ CONFIRMATION

INVISTIGATION/ CONFIRMATION

WHY ? 2.Why 1 why did the '' Why-2'' occur?

INVISTIGATION/ CONFIRMATION

INVISTIGATION/ CONFIRMATION LET US DO THIS TILL WE COME TO A LOGICAL SILLIEST WHY- BEYOND WHICH WE CANNOT PROBE- THAT WILL TAKE US TO THE ROOT OF THE PROBLEM After Phot countermeasure o

WHY WHY PHENOMENON (Problem side)Rejection Why ? Material Flow out of moulds as flashes Why ?Gap between upper and lower part of mould

Why ? Play generated in mould hinge pin Why ?

No provision to adjustWhy ? Fixed type hinge

Fixed type hinge

Adjustable type hinge

COUNTERMEASURES FOR DEFECT- WHY WHY

RECURRENCE PREVENTION KAIZEN POSITIVE INDIACTION SYSTEM JH/PM/WORK STANDARD TRAINING

KAIZEN - SHEETBrakes Division

Unit ACT

Sub Comm QM

Year

SL. No.

JiPm -TPM

Category: A

B

C

Providing

Changing

2000- 01 AU 087032505

Kaizen Theme & Target :Eliminate process scrap due to Component pull out in M270081 Cylinder in machine 032505

Machine No :

Team Members N.Kothandaraman Result / Benefit : 54 4Rejn Qty

Problem/Present Status :5 4 4Rejn Qty

Before improvement:

3 2 2 1 1 0 June July Aug Sep 2

3 2 2 1 1 0 0 June July Aug Sep Oct Nov 0 2

Analysis :Component damage duringmachining

After improvement:

Kaizen type

Reversible

Ir-reversible

Whycomponent pulled out

WhyTennon broken weaker section of the tennon

If reversible updated in Operation Standard / QCPC JH Check Sheet PM Check Sheet Eqpt / fixture DrawingScope & plan for Horizontal DeploymentSLNo. M/cNo. Target date Resp. Status

Why Why

Reduced thickness

Whyto avoid fouling with jaws

01 Tennon fouling with the jaws

032507

Oct,00

NKN

completed

Root Cause: Idea :

Poka Yoke type & Function

Shut Down Control Warning

Avoid tennon fouling with jaws

Prevention Detection

Counter measure Change the jaw design and tennon thickness :

Prerequisite for Why Why Analysis ENGINEERS MUST CULTIVATE THE FOLLOWING SKILL IN THEM ABILITY TO JUDGE ON-SITE WORK ABILITY TO JUDGE SETUP ADJUSTMENT ABILITY TO EVALUATE EQUIPMENT

How to Start Why why It starts from Action side or Phenomenon (Problem side)