1. • EQUIPMENT FAILURES - PM
• SETUP & ADJUSTMENT
• TOOL CHANGE
• START-UP
• MINOR STOPS
• REDUCED SPEED
• DEFECT & REWORK -
QM
• SCHEDULED DOWN TIME -PM
• MANAGEMENT -OTPM
• OPERATING MOTION
• LINE ORGANISATION
• LOGISTICS
• MEASUREMENT & ADJUSTMENT
• YIELD
• ENERGY -PM
• TOOL DIE AND JIG
16 Major Losses16 Major Losses
2. Loss Structure During Production Activities (16 MajorLosses)
Operating Man-hours
Net Operational
Man-hours
Effective Man-
hours
Valued Man-
hours (Man-
hours for turnout)
Loading Man-hours
Working Hour
Operating Time
Net Operating
Time
Valued Operating
Time
Loading Time
9. Management loss
10. Operating motions
loss
11. Line organization loss
12. Logistics loss
13. Measurement and
adjustment loss
5MajorLossesObstructingManpowerEfficiency
Excluding man-hours
(Supported by other
departments)
Production
Man-hour
Line
organization
man-hour loss
Defects in man-
hour loss
Defects quality
loss
8. Shutdown loss
1. Equipment
Failure loss
2. Set-up and
adjustment loss
3. Cutting blade
and Jig change
loss
4. Start-up loss
5. Minor stoppage
idling loss
6. Speed loss
7. Defects and
rework loss
Other downtime
loss
Clearing
checking
Awaiting
instruction
Awaiting
materials
Awaiting
personnel
distribution
Quality
confirmation
(Adjustment of
measurement)
8Majorlossesobstructingequipmentefficiency
Scheduled
downtime
Downtime
Performance
loss
Start-up loss
Overload loss
Temperature
loss
14. Energy loss
Input energy
Effective
energy
No. of qualified
products
Input materials
(Number, weight)
Weight of
qualified
products
Defects quality loss
Start-up loss
Cutting loss
Losses in weight
Losses in overages
(Increased
commission)
16. Yield loss
15. Die, tool & jig
loss
Efficiency of material, die, jig, tool and energy requirement per product unit
....
3 Major losses obstructing efficiency of material, Die, Jig & energy requirement per
product unit
3. (1) Failure losses
The definition of failure loss is set as follows:
Cases accompanied by function stoppage or decline (normally or typically
accompanied by production stoppage or output decline)
Cases requiring replacement of parts or repair in order to recover function
Cases requiring 5-10 minutes or more for repair
• At any rate, failures must be reduced to zero. This can be attained
at little cost, although some short-term investment may be
necessary. To attain zero failures, it is necessary to correct the
conventional misconception about BM (breakdown maintenance)
that failures are unavoidable
4. GENERAL PROBLEMS WITH FAILURES
Low interest by production sector
• Production thinks failures should be handled by maintenance.
Weak attitude toward failure analysis.
• Phenomena are not observed in details.
• Broken locations and places nearby are not examined fully.
• Enough ‘Genbutsu’ is not collected and analyzed.
• Causes are not pursued fully and only actions are taken.
• Measures for preventing recurrence are not taken.
• Failures are not analyzed at on-site.
Maintenance system and operation of it are weak.
• Check criteria are not defined, eg., checking frequency, locations, method and criteria.
• Maintenance calendar easily showing parts replacement and overhauling periods, oiling and
oil
change, and other items and operation system for it are week.
• Failure history system.
Attitude toward predictive maintenance (CBM) is weak.
• Measured values fluctuate greatly and re not reliable.
• Measured values do not change for a long time and lose confidence in audit results.
• Periodic measurement and trend control are not implemented.
6. (2) Setup and adjustment losses
"Setup and adjustment losses" refers to time losses from the end of the
production of a previous item through product-change adjustment to the
point where the production of the new item is completely satisfactory.
Setting up means a series of operations from the removal of jigs and
fixtures following the end of production, clearing up and cleaning, through
the preparation of jigs/tools and metal fixtures necessary for the next
product, to their attachment, adjustment, trial processing, readjustment,
measurement, production, and finally the ability to produce excellent
products
Contd…..
7. Adjustment means the following:
Taking measures to implement optimum solutions/values
for specific purposes, for instance, steps to restrict quality
within a target value range or to prevent other problems.
Attaining certain aims through repeated trial and error.
The approach to be adopted should be to study the adjustment
mechanism and seek time reduction. The ultimate goal of the
approach is "minimisation.' The final objective of set-up &
adjustment losses is to realise “one-shot machining in which quality
production is possible ”.
To realize one-shot arrangements, it is essential to reduce adjustment
to zero.
9. Why can’t we achieve One-step defect free change over ?
•We assume that adjustments are simply inevitable in a high
precision process
•Our equipment and replaceable parts have poor precision so we
make adjustments to compensate
•The standards mounting points are not clearly defined with
numerical values so people have to guess at the setting.
•We don't know the proper machining conditions or if we do we
aren’t applying that knowledge during set-up. (No standards
procedures)
10. Steps of promoting single step defect free change over
Understand the
current process &
condition
Clarify the problem
areas in changeover
adjustment & test runs
Check the
precision of the
equipment and
replaceable parts
Improve your
positioning
methods
Take care of
remaining
adjustments
Carry out PM analysis
( systematic thinking using the
principles & stds of the process)
Look again
at stds
values &
check the
items
related to
eqpt
precision
Look
again at
the
machining
condition.
Look again
at
durability.
Look again
at the
quality of
pervious
machining
Create
changeover
Stds:
Maintain &
management
11.
12. (3) Cutting-blade losses
These are time losses due to regular cutting-blade exchanges and
extraordinary replacement necessitated by blade damage and volume
losses (defects and rework) that arise before and after blade replacement.
Cutting-blade losses are dropping due to material and shape studies
yielding longer blade life, but they still pose a problem requiring further
study.
In the case of transfer machines, cutting- blade losses may account for
10% to 12% of overall efficiency impedance, because the number of
operators is few in relation to the number of the machines.
The reduction of cutting-blade losses requires study in both the fields
of relevant technology (material changes, shape alteration, etc.) and
software (vibration measurement and pursuit of optimum cutting
conditions). The target is the maximisation of blade life
13. (4) Start-up losses
Start-up losses are defined as time losses from
•start-up after periodic repair,
•start-up after suspension (long-time stoppage),
•start-up after holidays,
•start-up after lunch breaks,
to the time when it is possible to produce excellent products of reliable quality,
free from machine problems (minor stoppages, small problems, and blade
breakdown) in a specified cycle time operation, as.well as volume losses
(defects/ rework) that arise during that period.
14. • Method of reducing start-up losses
– Time-series data at the time of start-up
– Examination of working oil/lubricating oil
– Examination of related equipment portions
– Adjustment of thermal displacement occurrence
portions
– Measurement of thermal displacement values
– Countermeasures
15. 5) Minor stoppage & idling losses
The definition of these losses is as follows:
• Losses that are accompanied by temporary functional stoppage
• Losses allowing functional recovery through simple measures
(removal of abnormal work pieces and resetting)
• Losses that do not require parts exchange or repair
• Losses that require from 3-5 seconds to less than 5 minutes for
recovery.
Unlike failures, minor stoppage/idling losses represent the condition in
which equipment stops or idles because of temporary problems; for
example, a work piece clogs a chute, or a sensor is triggered by a quality
defect, temporarily stopping the machine. In this case, if the work piece
is removed and resetting is done, the machine will operate normally.
Thus, this condition is different in character from equipment failure
16. GENERAL PROBLEMS ON MINOR STOPPAGES
• Efforts to actualize as losses are not sufficient.
• Actions taken are poor
- Only emergency measures are taken as temporary measures.
• Phenomena are not discerned fully.
• Obstruction to un-attended operation.
- Operators are used for restoration.
- Minor stoppages keep operators from operating multiple stations or
machines.
- One minor stoppage will ruin the effects of unattendance operation during
breaks
17.
18. 7) Defect / Rework losses
Defect/rework losses are defined as volume losses due to
defects and rework (disposal defects), and time losses
required to repair defective products to turn them into
excellent products.
Generally, sporadic defects are easily fixed, so they are rarely
left uncorrected. Chronic defects, in contrast, are often left as
they are, because their causes are difficult to perceive and
measures to correct them are seldom effective. Rework and
repair items are also regarded as chronic defects, because
modification worker-hours are required
19.
20. Basic principle of quality maintenance
Quality Defects
Defects due to
equipment
precision
Defects due to
Machining
conditions
Defects due to
People
involved
Creation of equipment that
doesn’t produce defects
Train operators who know
their equipment well
Setting std: conditions for
equipment that doesn’t
produce defects
Fostering maintenance
management ability
Management of std: condition that doesn’t produce defects
Zero defects
21.
22. Overall Equipment Effectiveness -
OEE
• A Formula for measuring
Equipment Utilization and
Performance
• Uses an “Industry Standard” list
of Downtime Reasons
• The data required for accurate
OEE calculations can provide
MTBF’s, MTBE’s, and MTTR’s
information for equipment.
23. Overall Equipment Effectiveness
OEE = Availability x Performance x Quality
where:
Availability = Equipment Availability
Performance = Performance Efficiency
Quality = Quality Rate
(The OEE Equation)
24. Loading time - Downtime
Loading Time
= x 100Availability
Performance
efficiency
Processed amount
Operating Time/ Theoretical cycle time(@
100% eff & without Occ Time )
x 100=
Rate of quality
products
Processed amount - defect amount
Processed amount
= x 100
FOR OEE
25. Relationship between Six MajorLosses on Equipment and Overall Equipment Effectiveness
Availability
Loading time - Downtime
Loading Time
= x 100
= x 100 = 87%
460 mins. - 60 mins.
460 mins.
(e.g.) : Availability
Performance efficiency
Theoretical cycle time x processed amount
Operating Time
= x100
= x 100 = 50%
0.5 mins./unit x 400 units
400 mins.
(e.g.) : Performance efficiency
Rate of quality products
Processed amount - defect amount
Processed amount
= x 100 =
= x 100 = 98
%
400 units - 8 units
400 units
(e.g.) : Rate of quality products
Overall equipment effectiveness = Availability x Performance efficiency x Rate of quality products
(e.g.) 0.87 x 0.57 x 0.98 x 100 = 42.6%
Equipment
failure
1
Operating
time
Downtime
losses
Net
operating
time
Speedlosses
Valuable
operating
time
Defectlosses
Loading time
Setup and
adjustment
2
Idling and
minor stoppage
3
Reduced
speed
4
Defects in
process
5
Reduced
yield
6
Equipment Six Major Losses Calculation of overall equipment effectiveness
26. Relationship between Six MajorLosses on Equipment and Overall Equipment Effectiveness
Availability
Loading time - Downtime
Loading Time
= x 100
= x 100 = 87%
460 mins. X 60 mins.
460 mins.
(e.g.) : Availability
Performance efficiency
Theoretical cycle time x processed amount
Operating Time
= x100
= x 100 = 50%
0.5 mins./unit x 400 units
400 mins.
(e.g.) : Performance efficiency
Rate of quality products
Processed amount - defect amount
Processed amount
= x 100 =
= x 100 = 98
%
400 units - 8 units
400 units
(e.g.) : Rate of quality products
Overall equipment effectiveness = Availability x Performance efficiency x Rate of quality products
(e.g.) 0.87 x 0.57 x 0.98 x 100 = 42.6%
Equipment
failure
1
Operating
time
Downtime
losses
Net
operating
time
Speedlosses
Valuable
operating
time
Detectlosses
Loading time
Setup and
adjustment
2
Idling and
minor stoppage
3
Reduced
speed
4
Defects in
process
5
Reduced
yield
6
Equipment Six Major Losses Calculation of overall equipment effectiveness
9. Management loss
27. Overall Equipment Effectiveness =
A x P x Q
Processed amount - defect amount
Loading Time/ Theoretical cycle time(@ 100% eff &
without Occ Time )
28. For Calculating the OEE for the line,
the line is considered as one entity (machine)
1
3
2
4
5
7
6
8
IN
OUT
Std output of the line is taken
29. Overall Planned effectiveness
Availability
Loading time - Downtime
Loading Time
= x 100
= x 100
(e.g.) : Availability
Performance efficiency
Actual average Production
Standard production
= x
100
= x 100
(e.g.) : Performance efficiency
Rate of quality products
Production - 7 8
Production
= x 100 =
= x 100
(e.g.) : Rate of quality products
Overall planned effectiveness = Availability x Performance efficiency x Rate of quality
products
Planned Maintenance
& Equipment
failure
1
Running B
Hours
Lossby
Suspension
Operation C
Hours
Lossby
stoppage
Net
Operation
Hours
D
LossByCapacityCalander Hours
A
Production
control
2
Equipment
breakdown3
Process
breakdown4
Regular
Production5
Irregular
production6
Equipment Six Major Losses Calculation of overall equipment effectiveness
Valuable
operating
timeE
LossBy
Deficiency
Process
deficiency
7
Reprocessing
8
C
A
C
D
D
E
30. Loading time - Downtime
Loading Time
= x 100Availability
Performance
efficiency
Processed amount
Operating Time/ Theoretical cycle time(@
100% eff & without Occ Time )
x 100=
Rate of quality
products
Processed amount - defect amount
Processed amount
= x 100
FOR OPE
( Down time include Scheduled down time also )
31. PRODUCTIVITY
MEASUREMENT SYSTEM
Performance Efficiency
OEE
Quality Rate
Setup AdjustBreakdowns Tooling
Availability
Startup Losses
•Maintenance repair
histories
•Operator log sheets
•Equipment failure reports
•Process Controllers
Examples:
•Wear Part failure
•Utility failure
•Equipment jam
•Lubrication failure
•Process Controllers
•Production schedules
•Setup log sheets
•Tool changeover report
•Production control system
Examples:
•Part Changeover
•Die Change
•Tooling Change
•Limit Switch adjust
•Set point Adjustment
•Running of test Parts
•Process Controllers
•Production log sheets
•FMEA
Examples:
•Cutting tool wearout
•Injection Mold failure
•Stamping Die failure
•Operator log sheet
•Process Controllers
•Production count
•Start meters
Examples:
•Injection Molding
machine partial full on
initial run.
Idling & Minor
Stoppages
Speed Losses
•Process Controllers
•Operator log sheet
Examples:
•Running at less than
design speed to meet
quality specifications
•Not knowing the
capability of a machine
or line.
•Operator check off
document
•Process Controllers
Examples:
•Machine Jam
•Manual adjustment
•Material misalignment
•Machine reset
•Production Reports
•Quality Control
Charts
•Reject rates
Quality Defects
Major Losses
32. Set model
equipment
Organise the
project team
Improvementof
equipmentefficiency
Track Seven
major Losses
Select the theme
& plan
implementation
Individual
improvements
project activities
Individual
improvements
project
activities
Reliability in
use- prevention
stds & review
Autonomous
maintenance
system
Preventive
maintenance
system
Horizontal
deployment
Bottle neck process
Large loss
More H.D applicable
Matching with JH machine
Eqpt Failure loss
Minor stoppage loss
Set up and adjustment loss
Cutting tool & jig change loss
Start up loss
Reduced speed loss
Defect & rework loss
}
}
Function failure
loss( Failure
analysis technique)
Function
depression loss
(IE, QC, VE)
Challenge ‘0’ seven major losses through
project activities under each theme
Individual improvement
33. Sporadic & chronic losses
Division Sporadic loss Chronic loss
Loss Mode
Entirely new phenomenon suddenly
occurs. Phenomenon occurs suddenly
after exceeding a certain dispersion
range
Phenomenon occurs within a certain dispersion
range
-Repeated in short cycles
-Phenomenon always occurs with certain
quantitative dispersions
Actualization
Recognized as loss compared with
present level.
Actualize as loss compared between maximum
value and technical level
Cause
Casual sequence is relatively
monotonous. Can be guessed by past
experience and intuition in many cases
Casual sequence is not clear and cause system
is compounding. Past experience and intuition do
not work.
Countermeasure
Most cases can be solved on the spot.
Restorative measures will work.
Cannot be solved even if various actions are
taken. Renovating countermeasure are needed.
34. Chronic problems
Two types of chronic problem.
1) Problems produced by a single cause but the causes varies from
one occurrence to the next.
2) The problem is produced by a combination of causes,which also
varies from one occurrence to next
Cause
Cause
Cause
Cause
Cause
Cause
Cause
Cause
Difficulty in pin pointing the cause
35. Approach to Chronic Loss Reduction.
1. Analysis Phenomena
2. Review Potential
cause-and-effect relationships.
} Conduct P-M analysis
as part of this approach
3. Expose slight defects hidden
within causal factors
In exposing slight defects:
• Define optimal conditions
•Treat even the slightest
flaws as significant
•Restore optimal conditions
Editor's Notes
Sporadic losses are bound to attract attention, and therefore countermeasures are readily adopted. Frequent chronic losses, however, may remain un-amended because various countermeasures are ineffective. Since these losses account for the largest weight, each plant takes countermeasures on a priority basis, but the current status seems to be that correction cannot be achieved as desired. To address failure losses, it is necessary to study measures to raise the reliability of equipment and its maintainability to reduce downtime.