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1
PEOPLE SUPPORTIVE PRACTICE
LEAD TIME
20
REDUCTION
KEYS
LEVELING/ SMALL LOT
EMPLOEE INVOLVEMENT/ WHITE SHIRT
People Excellence Production Excellence
Business Excellence

PROCESS CAPABILITY SIX SIGMA

Pull System

Quick Set-up
TOTAL PRODUCTIVEMAINTENANCE
CONTAINER
-IZATION/ TRANSPOR- TATION
WPO VISUALMANAGEMENT
Error Proofing Error
2
Goals

• To understand the principles of
• ERROR PROOFING, the reasoning
• behind it, and the processes of developing Error
  Proofing (poka-yoke) devices

3
Objectives

• Improve quality (reduce PPM scrap)
• Make the processes easier and more capable
• Analyze cell for possible Error Proofing
  opportunities
• Develop Error Proofing devices and ideas

4
Error Proofing Is

• The process of anticipating, preventing,
  detecting errors which adversely affect customers
  result in waste

5
Questions

• Will Error Proofing be more work to complicate
  our jobs even further?
• How does Error Proofing fit in the AMPS program?

6
Answer

• Error Proofing will make your job easier
• and safer!

7
How can the Error Proofing class be used?

• Catalyst for improvement
• Tool for reaching measurables
• Learning device

8
What Measurables does Error Proofing affect?

• PPM
• Scrap
• Process Capability

9
Other Benefits

• Safety Improvements
• Quality Improvements
• Ergonomic Benefits
• Promotes Design for Manufacturing

10

• Therefore
• Error Proofing Classes only help us reach our
  measurables for the overall goals established in
  our 20 Keys.

11
Error Proofing
Think Quality Think Right First Time Think
Zero Defects
12
Why Error Proofing?

• Maintain customer satisfaction
• Reduce cost
• Ability to maintain Continuous Improvement
  production methods and smaller inventories

13
Why Error Proofing?

• Safety
• Quality
• Scrap
• PPM
• Repairs

14
Safety Examples

• Light curtains

15
Safety Examples

• Light curtains

16
Safety Examples

• Palm buttons

17
1-100-1000 Rule

• If it takes 1 hour to fix a problem where
• it occurs, it may take 100 hours
  
• downstream, and it may take 1000 hours
  
  
• at the customer
• What are cost implications?

18
Error Proofing Directly Affects
World Class Benchmarks

• PPM 25 or less
• Scrap Less than 2
• Suggestions per employee 15 per year
• of suggestions implemented 85
• of employees on teams 100
• WIP hours Less than 4 hrs.
• Employees Cross Trained 100
• Supplier Days Inventory Less than 4 days

19
Parts Per Million

• PPM of 25
• 22,000 credit cards will have incorrect
• cardholder information on the magnetic
  strips.
• 55,000 pieces of mail mishandled each
  month.
• 18 unsafe plane landings at OHare each
  year.

20
Parts Per Million

• PPM of 25
• 19,000 spent annually on CDs and
• tapes that dont play.
• 4,000 checks deducted from the wrong
• bank accounts each day
• 50,000 documents lost by the IRS
• each year

21
Parts Per Million

• If 75,000 Total shocks and struts go out the door
  per day, then only 1.875 can be defective to meet
  the goal of 25 PPM
• When the customer gets that defective shock or
  strut, do they care that the other 74,998 were
  good?

22
Parts Per Million

• If 1000 exhaust systems are produced per shift.
  How many defects can we have and still be at 25
  PPM or less? .025
• When the customer gets that defective part or
  assembly, do they care that the other 999 were
  good?

23
3 Zeros

• Zero defects
• Zero waste
• Zero delays

24
Error Proofing

• Error Proofing
• 1. Simple and inexpensive
• 2. Automatic, or part of process
• 3. Placed close to mistake, minimizing
• damage

25
Error Proofing

• What are some everyday examples?

26
Examples

• Cannot start the car without it being in park

27
Examples

• Dryer stops when you open the door

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Examples

• Mower stops when you release the handle

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Inside the Refrigerator
Light goes out when you shut the door
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Exercise 1
List examples of error proofing in room
31
(No Transcript)
32
Module 2

• Error Proofing Devices
• and Defects

33
Error Proofing

• Uses techniques that prevent errors by
• Designing processes and products that cannot be
  incorrectly performed, manufactured, or assembled
• Using devices or inspection techniques that
  detect errors during the work process rather than
  at the end of the process

34
Error Proofing Devices

• Simple and inexpensive devices that are used to
  prevent errors about to occur or detect errors
  and defects that have occurred.

35
Errors and Defects

• An example of an ERROR would be
• Loading a part incorrectly in a fixture
• A DEFECT would be
• if that machine were cycled and a bad part
  produced

36
Error Proofing

• Five Manufacturing examples
• Guide pins
• Error detection and alarms
• Limit switches
• Counters
• Checklists

37
Examples

• Guide pins allow only the correct baffle to be
  loaded in the press

38
Examples

• Guide pins are used to check alignment of the
  flange.

39
Examples

• Assembly/Mounting Error

40
Examples

• Limit Switch

41
Ten Causes of Errors

• Processing omissions
• Leaving out one or more process steps.
• Processing errors
• Process operations not performed according to the
  standard work procedures.
• Error in setting up the work-piece
• Using the wrong tooling or setting machine
  adjustments incorrectly for the current product

42
Ten Causes of Errors

• Missing parts
• Not all parts included in the assembly, welding,
  or other processes
• Improper part/item
• Wrong part installed in assembly
• Processing wrong work piece
• Wrong part machined

43
Ten Causes of Errors

• Operations errors
• Carrying out an operation incorrectly having the
  incorrect revision of a standard process or
  specification
• Adjustment, measurement, dimension errors
• Errors in machine adjustments, testing
  measurements or dimensions of parts and gages

44
Ten Causes of Errors

• Errors in equipment maintenance or repair
• Defects caused by incorrect repairs or component
  replacement
• Errors in preparation of blades, jigs, or tools
• Damaged blades, poorly designed jigs, or wrong
  tools

45
Five Causes of Human Errors

• New worker
• Not familiar with operation
• Forgetfulness
• Lack of concentration and standards from one part
  to the next
• Willful errors
• Operator thinks his/her way of doing things is
  best
• Lack of standards
• No standardization of work implemented
• Surprise errors - equipment
• Equipment failures or wrong setup

46
Traditional Management Cycle

• Error takes place
• A defect occurs as a result
• This information is fed back
• Corrective action is taken accordingly

47
Traditional Alternatives

• 100 Inspection
• SPC

SPC
48
Error Proofing

• 100 Inspection
• -Costly
• -Non-Value Added
• -Not fail-safe

49
SPC
Good Part
Are These Acceptable?
50
Error Proofing

• 99.9 Good
• 20,000 incorrect drug prescriptions
• will be written in next 12 months
• 12 babies will be given to the wrong
• parents every day
• 291 pacemaker operations will be
• performed incorrectly this year

51
Error Proofing

• 99.9 Good
• 811,000 faulty rolls of 35mm film will
• be loaded this year
• 268,500 defective tires will be shipped
• this year

52
Error Proofing

• So if SPC is not acceptable..
• Then?
• 100 inspection AUTOMATICALLY
• ERROR PROOFING

53
Exercise 2

• Existing error proofing
• Possible defects

54
(No Transcript)
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Module 3

• Inspection
• and Zero Defects

56
Who is the best inspector?
57
YOU
The User
58
Types of Inspection

• Self-checking - Before handoff
• Joint-inspection - During handoff
• Successive check - After handoff
• Source inspection - Immediately after mistake,
  but before it results in a defect

59
Types of Inspection

• Three Approaches
• Judgment
• Discovers defects after they have happened
• Informative
• Reduces defects but doesnt prevent them
• Source
• Catches errors before they cause defects

60
Source Inspection

• An error takes place
• Feedback is carried out at error stagebefore it
  becomes a defect
• Corrective action is taken accordingly

61
Source Inspection

• 1. Source inspection to PREVENT errors
  before they cause defects2. 100 inspection
  using inexpensive devices3. Action to stop
  operations when defect is detected

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The Eight Principles of Basic Improvement For
Error Proofing and Zero Defects

• 1. Build quality into the processes

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The Eight Principles of Basic Improvement For
Error Proofing and Zero Defects

• 2. All inadvertent errors and defects can be
  eliminated

64
The Eight Principles of Basic Improvement For
Error Proofing and Zero Defects

• 3. Stop doing it wrong and start doing it right-
  NOW!

65
The Eight Principles of Basic Improvement For
Error Proofing and Zero Defects

• 4. Dont think up excuses, think about how to
  do it right

66
The Eight Principles of Basic Improvement For
Error Proofing and Zero Defects

• 5. A 60 chance of success is good enough,
  Implement your idea NOW!

67
The Eight Principles of Basic Improvement For
Error Proofing and Zero Defects

• 6. Mistakes and defects can be reduced to ZERO
  when everyone works together to eliminate them

• Zero defects
• Zero waste
• Zero delays

68
The Eight Principles of Basic Improvement For
Error Proofing and Zero Defects

• 7. Ten heads are better than one

69
The Eight Principles of Basic Improvement For
Error Proofing and Zero Defects

• 8. Seek out the true cause using the 8D
  (disciplines) Process

70
The 8 Step Problem Solving Process

• Step 1 Use team approach
• Step 2 Describe the problem
• Step 3 Implement short-term corrective action

71
The 8 Step Problem Solving Process

• Step 4 Define and Verify root cause(s)
• Step 5 Implement permanent
• corrective action

72
The 8 Step Problem Solving Process

• Step 6 Verify effectiveness of corrective
  action
• Step 7 Prevent Recurrence
• Step 8 Congratulate team

73
Use Team Approach
Congratulate the Team
8-D
Implement Short-term Corrective Action
Verify Effectiveness of Corrective Action
Define and Verify Root Causes
Prevent Recurrence
Implement Permanent Corrective Action
74
Error Proofing

• Operator discovers error
• Stops process
• Quick fix (authorized by Q.A.)
• Submit operational problem
• Team formulated
• Run problem through 8D
• Arrive at solution
• Apply solution

75
Module 4

• Error Proofing Devices

76
Which Operations?

• High error potential
• Vital characteristics or damage potential
• Failure history
• Complex operation or much routine detail

77
Developing an Error Proofing Device

• Describe defect, show defect rate, form
  prevention team
• Identify location of the defect occurrence
• Detail current standards/operating procedures
  where defect was made
• Identify any deviation from standard

78
Developing an Error Proofing Device

• Identify red flag conditions (next slide), 5 whys
  error happens, until root problem discovered
• Identify error proofing device required
• Create error proofing device and test for results
• CONTINUALLY IMPROVE

79
Red Flag Conditions

• Adjustments
• Tooling and tooling changes
• Dimensions/ specifications/ critical conditions
• Many or mixed parts
• Multiple steps
• Infrequent production
• Lack of an effective standard

80
Red Flag Conditions

• Symmetry
• Asymmetry
• Rapid repetition
• High / extremely high volume
• Environmental conditions

81
Methods for Using Error Proofing Devices

• Contact method
• Fixed-value method
• Motion-step method
• Warning method

82
Methods for Using Error Proofing Devices

• Contact Methods
• Works by detecting whether a product makes
  physical or energy contact with a sensing device

83
Contact Method Example

• Guide pins align flange and also make it
  impossible to put the flange upside-down

84
Contact Method Example

• Tab aligns opening

85
Contact Method Example

• Notch in aligns flange

86
Contact Method Example

• Rubber O-ring centers tubing

87
Contact Method Example

• Notch ensures proper seam alignment for welding

88
Contact Method Example
Notch is not visible showing an incorrectly
loaded part

• Notch is visible showing a correctly loaded part

89
Contact Method Example

• Guide pins align blank for stamping

90
Methods for Using Error Proofing Devices

• Fixed-Value Method
• Can be used when a fixed number of parts or
  operations needs to be performed

91
Fixed Value Method

• Counter counts the number of welds made and
  lights after six welds

92
Methods for Using Error Proofing Devices

• Motion-Step Method
• Used to sense whether a motion or step in the
  process has been carried out within a certain
  expected time

93
Methods for Using Error Proofing Devices

• Warning Method
• Activate a light, buzzer, etc. to signal operator
  of abnormalities

94
Types of Sensing Devices

• Physical contact sensing devices
• Energy sensing devices
• Sensors that detect changes in physical conditions

95
Types of Sensing Devices

• Physical Contact Sensing Devices
• Detect the actual presence or lack of presence of
  a device or part

96
Physical Contact Sensor
No Part
Part Present

• Touch switch used to sense that the full length
  of stock has been fed into the press

97
Physical Contact Sensor

• Contact switch used to detect if a rod is too long

98
Types of Sensing Devices

• Energy Sensing Devices
• Use energy (photoelectric etc.) to determine
  whether an error is occurring

99
Energy Sensing Devices

• Photoelectric switches
• proper size or color
• passage of an object
• proper supply of parts
• proper feeding of parts
• Beam sensors
• Proximity switches

100
Photoelectric
101
Types of Sensing Devices

• Change in Physical Conditions
• Detect changes in pressure, temperature,
  electrical current, etc.

102
Change in Physical Condition

• Pressure
• Temperature
• Electrical current
• pH

103
Error Proofing Case Study

• Problem 1
• Processing Omissions
• Problem
• An operator is responsible for drilling six
  holes. Sometimes he/she loses count and drills
  too few holes.
• Suggestions To Improve

104
Error Proofing Case Study

• Problem 2
• Processing Errors
• Problem
• In the final assemble/packaging of shocks,
  customer part numbers change several times a day,
  operators sometimes use the incorrect component
  package.
• Suggestions To Improve

105
Continuous Improvement Activity Sheet
Team
Line
Facility
Idea
Date Submitted
Date Required
Date Completed
Champion
Team Contact
Effect
W. O.
106
(No Transcript)
107
Exercise 3

• Brainstorming and proposed solutions

108
Module 5

• Tracking and Identification

109
(No Transcript)
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(No Transcript)
111
Tally Sheets
112
Multiple Counters

• Counters are attached to the point of use.

113
Ask Why Five Times
Problem The Cup wont fit on the Tail End of
The Tail Pipe. 1. Why? 2. Why is the tab too
wide? 3. Why does it flatten out? 4. Why is the
temp wrong? 5. Why set improperly?
114
Ask Why Five Times
Problem The bracket on the struts will not
hold. 1. Why? 2. Why is the weld breaking? 3.
Why is the bracket misaligned? 4. Why is the
fixture misaligning the bracket? 5. Why is the
weld slag built up?
115
B.O.S. Chart

• Is a one page chart showing data trends
  identifying key factors, tracking projects and
  monitoring improvements

116
Why Use The B.O.S. Chart Tool?

• B. O. S. charting is a standard tool used to
  support visual control
• One page summary which facilitates management at
  a glance
• Ensures real activities are occurring to improve
  the areas identified as important to the company
• Is an excellent communications tool
• to employees
• to management

117
B.O.S. Chart Format

• Key Measurable
• Target
• Trend Line

Improvement
Activities

• Data Analysis
• Pareto

Improvement
Tracking
118
B.O.S. Key Measurable PPM
300
Ref
Description
Resp.
End Date
250
1
Redesign finished goods packaging
AM
7/18/95
200
Procure new component parts
150
2
JK
6/30/96
containers
100
3
Improve weld in process weld
SL
7/24/95
monitoring system
50
4
Replace current controller on paint
GA
9/20/95
0
system
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Actual
Target
50
Ref
Description
Jan
Mar
May
Jul
Sept
40
Damaged
1
51
48
45
39
5
Assembly
30
2
20
20
18
20
19
Cracked Casing
20
3
Broken Weld
19
17
21
18
1
10
4
Paint Blister
14
19
18
10
14
0
Damaged Assembly
Cracked Casing
Broken Weld
Paint blister
119
Error Proofing Identification
Description of Error Proofing device
Description of Error Proofing device
Description of Error Proofing device
P1
P3
P2
120
Error Proofing Identification

• The P symbol shall be approximately 3inches
  (75mm) wide and 4 inches (100mm) tall, and
  attached on or near the Error Proofing device.

121
Error Proofing Identification SOURCE INSPECTION

• P1 Device
• (Green)
• An Error Proofing device that prevents an error
  from occurring

122
Error Proofing Identification INFORMATIVE
INSPECTION

• P2 Device
• (Purple)
• An Error Proofing device that detects an error in
  time to allow rework before it becomes a defect
  and prevents further errors of the same type

123
Error Proofing Identification JUDGEMENT
INSPECTION

• P3 Device
• (Blue)
• An Error Proofing device that detects a defect
  and eliminates it from the flow of good products
  before it reaches the customer.

124
Error Proofing

• Of the three types of Error Proofing devices
  mentioned, which is the best one to use?

125
Continuous Improvement

• P1
• This does not mean that they all have to be
  P1s, a P3 is better than nothing, but we should
  continually improve all of the error proofing
  devices

SOURCE INSPECTION
126
Critical Operations or Points

• Identify where a
• defect is most likely to occur
• error proofing device is needed but has not yet
  been developed

CRITICAL POINT (Gray)
127
What happens if an Error Proofing Device Fails?

• A lot of defective parts could be produced

128
Maintain the Error Proofing Devices

• Error proofing devices
• can and do sometimes fail
• need to be checked at the beginning of each shift
• need to be properly maintained

129
Testing Error Proofing Devices

• Keep safety in mind
• Understand the function of the device and what it
  detects
• May need to have a defective part to cycle and
  see if defect is detected

130
Exercise 4

• Label error proofing devices and critical
  operations
• Implementation plan

131
(No Transcript)