5 effect of rejects on the time taken for the production of air ducts
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5.1
5. EFFECT OF REJECT ON PRODUCTIONTIME
5.1 Introduction
The effect of the rejects on the production time, are major, on the production
time, which will increase in the time taken for the production of the automobile air ducts.
Before considering the effects of rejection on production, time, the parameters
causing the rejection should be very well known, to the individual. These parameters
should be well characterized, and thus its effect on the production time can be predicted.
After the characterizing, we found out that the parameters are of three types.
1. Parameters, that causes defects, but cannot be controlled by taking theprecautions, but the severity of such failure can be reduced by taking the
remedies.
Example: Blow molding machine malfunction, & receiving of raw
material, and failure of transport during dispatch of the finished Goods
2. Parameters, that causes defects, but can be controlled by taking theprecautions, and the occurrence of such failure can be avoided by taking
precautions
Example: rejection due to wrong clamping
If the above parameters are taken care of, the production time will increase that
will increase the yield of the company, generating more revenues of the company.
For, further examination of the effect of rejects on the production time a detailed
fishbone is to be constructed, which will help us, to understand the failures that causes
the rejection, Main causes that creates those failures, and the sub causes that are
responsible for the main cause. The tabular for mat of the same is shown in Table 5.1.
The fishbone of the problem will be constructed and then, studied in figure 5.1.,
and the parameters will then be identified under the above category.
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5.2
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5.3
Table 5.1.1 Effect of rejection on Product Manufacturing time
Cause: 02 Cause: 03 Cause: 04
Wrong or improper die setting Improper excess material removal Wrong clamp fitting Wrong a
Unskilledworker
Dimensions notknown toworker
Unskilledworker
Inexperience worker
difficultyinidentification dueVerysimilarlookingclamp LH &RH
Burdononworkerdue torepetitive task
in shorttime
Workerdonthaveknowledge ofassembl
processs
Wrong clamp usage Wrong foam / glue used
Damagedclampused forassembly
Wrongmaterialsupplied bysupplier
Wrongmaterialordered
Wrongmaterialsuppliedby supplier
Wrongmaterialordered
Damaged Die used Machine Breakdown
Impropermaintenance of die
Improperstorageof Die
Improperpreventivemaintenan
ce ofmachines
Partsnot
available atstore
In-housemaintenance person
notavailable
Improper excess material
removal
Dimension
s not
known to
worker
Unskill
ed
worker
Over heating of blow molding
machineImproper Goods storage
Ventilationis not proper
Machinecooling system
not working
improperstoragetemperatur
e
excess moisture inthe air damages thegoods
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5.4
Wrong process
parameters setting in
Blow molding machine
Wrong or improper die
setting
Wrong
Improper excess material
removal
People
Inexperience
worker
Machine operating
illiteracy
Unskilled
worker
Unskilled workerDimensions
not known to
worker
Inexperience
worker
Difficulty in
identification
due Very
similar looking
clamp LH & RH
Burdon on workre etitive task i
Wrong
selection ofsub parts for
assembly
Improper selecti
temp for heatin
Storage
Finished
at wrong
Wrong foam /
lue used
Wrong
material
ordered
Wrong materialsupplied by
supplier
Equipmen
Wrong process parameters setting
in Blow molding machine
Improper excess material
removal
heating of blow molding
ne
Raw material damaged
Method
Improper storage temperature
Excess moisture in the air damages the material
Ventilation is not proper
Machine cooling system not working
oper storage temperature
d clamp used for assembly
Process parameters are not validated
Process parameters are not available at machine
Unskilled worker
Dimensions not known to worker
Machine Malfunction
Non - calibrated machine
Wrong process Parameters
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5.5
Some, parameters are identified, and considered for the reducing the rejects, and
increasing the time taken for the production. They are as follows.
1. Raw material receiving & transportation of the finished goods to the customer.2. Blow Molding Machine functionality3. Reduction in the rejects due to wrong clamping
The first two parameters are characterized in category one, while the third
parameter is characterized in category two. The effect of category two on the process is
much more severe than the category one, but the occurrence level is low, thus it results in
moderated RPN. Similarly the category two has less severity, but its occurrence is high,
so, RPN value will be moderate, but both these parameter has impact on the time for
production, so cannot be neglected. After the FMEA implementation, its impact can be
observed in the production time, by calculating the initial and final production time.
5.2 Receiving raw material from the supplier and transporting
of the finished goods to the customer
5.2.1 Receiving raw material from the supplier
The process of manufacturing of the air ducts starts from the receiving of raw
material from the supplier to the transportation of the finished goods to the customer.
The first and the last operation are major operations that should be taken care.
Completing the whole operation of manufacturing and dispatch of the goods is not
possible, if these two major operations are avoided.
No manufacturing of any product can start if the raw material is not received on
time. If inventory management, is not followed by any organization, the late receiving of
the raw material will directly add in the idle time of the company, which will directly add
in the losses of the company, and no operation can be started can be started without raw
material receiving.
In the FMEA, as the occurrence of this type of potential failure is less, also, the
detection is easy, both the occurrence an detection are rated low. The severity of this
kind of failure will be rated high, as it will have severe effect on the operation followed.
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5.6
The RPN, i.e. the product of severity, occurrence and detection comes out to be low
again, due to low ratings of occurrence and detection. But the severity in this operation
is very high, which cannot be neglected due to adverse effects on other operations.
The effect of the failure mode will be different at different levels of production.
The next operation will be impossible to perform, at assembly the material will not
available for the assembly, at customer level more time taken to fulfill the orders that
will cause dissatisfaction, while the end customer will be dissatisfied.
There are two potential causes to the failure due to material not received on time
1. Transport malfunction2. Material not dispatched by the supplier on timeThe current process control or prevention method for the potential failure of raw
material not received on time would be asking the delivery well before the time of its
utilization; also proper intimation should be given to the supplier for delivering the raw
material on time. This creates a chance that will avoid such a situation to rise.
5.2.2 Transportation of the finished goods to the customerThe dispatching procedure, in which the finish goods are dispatched from the
industry to the customer, should be taken particular care. There are many disadvantages
if proper care is not taken; some of them are as follows
a. The late dispatch will result into late delivery, which will result in an unhappyand dissatisfied customer.
b.
Industry will lose its reputation on its punctuality, in the market, and spoils itsmarket value.
c. If the product gets spoiled during dispatching, then the market value of thecustomer will be spoiled, also, it will result in customer dissatisfaction.
d. It can also affect further relationship with the customer company, due to latedelivery, or product getting spoiled during the process of dispatching.
The reasons which can cause these types of disadvantages should be concerned
about, and proper precautions should be taken to make sure that these types of
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5.7
disadvantages do not occur. This has to be done as the severity of these disadvantages
are very high and can create major problems to the company and its reputation in a long
run.
Table5.2.1 FMEA analysis for the Raw material not received on time
ProcessFunction
Requireme
nts
Actions
Taken
S e v
Oc c
D et
RPN
Raw
ma
teri
lal
no
t
rece
ive
don
time
NextOperation-
im
poss
ible
toperform
nex
tope
ration
Assly
-
ma
teria
lno
tava
ila
ble
for
theassem
bly
.
Customer-
more
time
tak
en
tofulfil
ltheorders
disa
tis
fation
.
EndCustomer-
dissa
tifa
ction
8
1.
transporta
tion
ma
lfun
tion
2.
ma
teria
lno
t
dispa
tch
ed
on
time
by
the
supp
lier
1
supp
lier
sh
ou
ldb
e
given
regu
lar
inima
tion
rece
iving
departmen
t
info
rms
the
pro
duc
tion
superv
isor
2
16
ActionResults
10Receiving
inspectiono
f
raw
materia
l
Current
Process
controls
Prevention
Current
Process
controls
Detection
D et e
R P N
Recom
mended
Action(s
)
Respon
sibility&
Target
Complet
Potential
FailureMode
PotentialEffect(s)o
fFailure
S e v
Cl a s
Potentialcause(s)/
Mechanism(s)of
Failure
Occ
ur
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5.8
5.3 Blow Molding Machine functionality
As blow molding is the main manufacturing process that is being considered inthe manufacturing of the air ducts. It is a process that is to be taken special care. If any
one out of the five blow molding machine fails in the industry, it will cause 20 % loss to
the total production and process, for the manufacturing of the Air Ducts. This will also
contribute a huge amount in the down time and the total losses incurred to the company.
To avoid this kind of failure or similar kind of failure to occur, the proper
maintenance schedule as directed by the blow molding machine manufacturer, should be
adopted and followed, for the proper functioning of the machine, also to avoid the
unwanted situation such as total machine repair time, to occur.
Though in FMEA, which we have done earlier, I have not considered a lot
potential causes in the blow molding machine functionality, since the occurrence is less,
bit the same cannot be neglected as the severity ratings are very high and cannot be
ignored.
The following the hydraulic circuit for the blow molding machine operation, the
maintenance schedule chart will depend on this hydraulic circuit.
When the solenoid 1 will be actuated, the first stage of the 4/2 DCV, will be
actuated, in that case the pressure will be in line 1. The line 1 consist of 3/2 DCV which
is roller actuated, and the closed position will be actuated, when the cylinder expands in
the forward position till platens 2. When the solenoid 2 will be actuated, the second
stage of the 4/2 DCV, will be actuated, in that case the pressure will be in line 2. The line
2 does not contain any 3/2 DCV so the cylinder will directly be actuated and will move
in the reverse direction.
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5.9
Figure5.3.1 control circuit for the Blow Molding Machine
Table 5.3.1 Maintenance steps for the blow molding machines
Repair Indicators
Service Options
Possible Causes Service Options
Leaks System pressure too high
Scored or bent cylinder rod
Failed or incorrect seals
Improperly torqued hose
connection
Worn or damaged hoses,
tubes and fittings
Missing guards
Hose service
Thorough visual machine
inspection
Maintenance and diagnostic
services
SOS Services
Custom Hydraulic Service
Excessive cylinder
drift
Valve adjustment needed
Scored cylinder
Failed seal or seals
Scored valve
Identification and
measurement
Diagnostic services
SOS Services
um
Line 1Line 2
4 2 DCV
3 2 DCV
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5.10
Contaminated oil Custom Hydraulic Service
Slow cycle times Engine performance
Faulty valve
Low fluid level
Worn system components
Contaminated oil
Machine measurements
compared to specs
Diagnostic services
SOS Services
Custom Hydraulic Service
Noisy operation Engine performance
Low fluid level
Restriction in system
Aeration
Worn system components
Faulty relief valve
Thorough visual machine
inspection
SOS Services
Custom Hydraulic Service
System overheating Faulty oil cooler
Low fluid level
Plugged filter
Worn system components
Faulty relief valve
Wrong viscosity or
contaminated oil
Restriction in system
Poor operator habits
Thorough visual machine
inspection
Maintenance and diagnostic
services
SOS Services
Custom Hydraulic Service
Loose cylinder joints Worn rod or cylinder Component inspection/repair
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5.11
eye/trunnion
Poor lubrication
Improper preventive
maintenance schedule
Custom Hydraulic Service
SOS Services High levels of wear
elements, dirt and
other contaminants in oil will
accelerate
component wear and erodesystem efficiency
Preventive maintenance
schedule consultation
Custom Hydraulic Service
5.3.1 Trouble shooting for the blow molding machines
Dirty Oil
1) Components not properly cleaned after servicing.
2) Inadequate screening in fill pipe.
3) Air breather left off. (No air breather provided or insufficient protection of air
breather).
4) Tank not properly sealed.
5) Pipe lines not properly covered while servicing machine.
6) Improper tank baffles not providing settling basin for heavy materials.
7) filter dirty or ruptured.
Fire resistant fluids
1) Incorrect seals cause binding spools.
2) Paint, varnish or enamel in contact with fluids can cause sludge deposits on
filters and around seal areas.
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5.12
3) Electrolytic action is possible with some metals. Usually, zinc or cadmium.
4 ) Improve mixtures can cause heavy sludge formations.
5) High temperatures adversely affect some of the fluids, particularly the water
base fluids.
6) Adequate identification of tanks containing these fluids should be provided so
that they will be refilled with the proper media.
7) As with mineral base oils, nuisance leaks should be remedied at once.
8) Make certain replacement parts are compatible with fluid media.
Foaming Oil
1) Tank line not returned below fluid level.
2) Broken pipe.
3) Line left out between a bulkhead coupling and the bottom of the tank after
cleaning.
4) Inadequate baffles in reservoir.
5) Fluid contaminated with incompatible foreign matter.
6) Suction leak to pump aerating oil.
7) Lack of anti-foaming additives.
Moisture in Oils
1) Cooling coils not below fluid levels.
2) Cold water lines fastened directly against hot tank causing condensation
within the tank.
3) Soluble oil solution splashing into poorly sealed tanks or fill pipes left open.
4) Moisture in cans used to replace fluid in tanks.
5) Extreme temperature differential in certain geographical locations.
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5.13
6) Drain not provided at lowest point in tank to remove water collected over
possibly long operating periods.
Overheating of System
1) Relief valve set too close to compensator pressure setting.
2) Water shut off or heat exchanger clogged.
3) Continuous operation at relief setting.
a. Stalling under load, etc.
b. Fluid viscosity too high or too low.
4) Excessive slippage or internal leakage.
a. Check stall leakage part pump, motors and cylinders.
b. Fluid viscosity too low.
5) Reservoir sized too small.
6) Case drain line from pressure compensated pump returning oil too close to
suction line.
a. Re-pipe case drain line to opposite side of reservoir baffling.
7) Pipe, tube or hose I.D. too small causing high velocity.
8) Valving too small, causing high velocity.
9) Improper air circulation around reservoir.
10) System relief valve set too high.
11) Power unit operating in direct sunlight or ambient temperature is too high.
Oil leakage around pump
1) Shaft seal worn.
2) Head of oil on suction pipe connection connection leaking
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5.14
3) Pump housing bolts loose or improperly torque.
4) Case drain line too small or restricted (shaft seal leaking).
Excessive pump wear
1) Abrasive dirt in the hydraulic oil being circulated through the system.
2) Oil viscosity too low.
3) System pressure exceeds pump rating.
4) Pump misalignment or belt drive too tight.
5) Air being drawn in through inlet of pump.
Troubleshooting Solenoid Valves
Solenoid failures
1) Voltage too low. If voltage is not sufficient to complete the stroke of the
solenoid, it will burn out the coil.
2) Voltage too high. Excessive voltage can also burn out coils.
3) Signal to both solenoids of a double solenoid valve simultaneously. One or
both of the solenoids will be unable to complete their stroke and will burn out. (Make
certain the electrical signal is interlocked so that this condition cannot exist).
4) Mechanical damage to leads. (Short circuit, open connections, etc.)
5) Tight spool or other mechanical parts of the valve being actuated can prevent
the solenoid from completing its stroke and subsequently burning out.
6) Replacement springs too heavy in valve. Overloads solenoid and shortens
life.
7) Dirty contacts may not supply sufficient current to solenoid to satisfy inrush
demands.
8) Low voltage direct current solenoids may be affected by low battery capacity
on cold mornings directly after starting cold engine. (DC)
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5.15
9) Long feed lines to low voltage solenoids may cause sufficient voltage drop
to cause erratic operation.
Solenoid valve fails to operate
1) Is there an electrical signal to the solenoid or operating device? Is the
voltage too low? (Check with voltmetertest light in emergency.)
2) If the supply to the pilot body is orificed, is the orifice restricted? (Remove
orifice and check for foreign matter. Flushing is sometimes necessary because of floating
impediment.)
3) Has foreign matter jammed the main spool?
(Remove end caps and see that main spool is free in its movementremember
that there will be a quantity of fluid escaping when the cap is removed and provide a
container to catch it.)
4) Is pilot pressure available? Is the pilot pressure adequate? (Check with
gauge on main pressure input port for internally piloted types and in the supply line to
the externally piloted type.)
5) Is pilot drain restricted? (Remove pilot drain and let the fluid pour into an
open container while the machine is again tried for normal operation. Small lines are
often crushed by machine parts banging against them causing a subsequent restriction to
fluid flow.)
6) Is pilot tank port connected to main tank port where pressures are high enough
to neutralize pilot input pressure? (Combine pilot drain and pilot tank port and check for
operation with the combined flow draining into an open containerblock line to main
tank from pilot valveif this corrects the situation, reroute pilot drain and tank line.)
7) Are solenoids improperly interlocked so that a signal is provided to both
units simultaneously? (Put test light on each solenoid lead in paral lel and watch for
simultaneous lightingcheck electrical interlock. This condition probably burns out
more solenoids than any other factor.)
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5.16
8) Has mounting pad been warped from external heating? (Loosen mounting
bolts slightly and see if valve functions. End caps can also be removed and check for
tight spool.)
9) Is fluid excessively hot? (Check for localized heating which may indicate an
internal leakcheck reservoir temperature and see if it is within machine specifications.)
10) Is there foreign matter in the fluid media causing gummy deposits? (Check
for contaminationmake certain seals and plumbing are compatible with the type of
fluid being used.)
11) Is an adequate supply of fluid being delivered to actuate the load? (Many
times there is sufficient pressure to shift the valve but not enough to actuate the work
load. Check pump supply pressure and volume if necessaryphysical measurement of
flow through relief valve with units blocked may be necessary.)
12) Check circuit for possible interlocks on pressure sources to valve or to pilot.
5.4 Rejects Due To Wrong Clamping
For, constructing Fishbone, there should an identified problem, on which the
work to reduce it has to be done. From the database, of previous FMEA, and also
considering the accounts for the rejects, it has been found out that the maximum rejects
were contributed by mainly one failure that is, Rejection due to wrong clamp fitting in
the air duct. Even if the problem is minor in its size, but is major, when it comes to the
rejection rate calculation.
The main parameters that are contributing to this problem are people, material,
equipment, method, and environment. There are different causes that are been identifiedwith the help of brain storming sessions that were held between the cross functional team
that was formed for the FMEA implementation in the Delta Blow Packs. The following
table 5.1 shows the main parameters and the causes that are contributing to these
parameters, which in whole contributes to the main failure and cause the problem.
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5.17
Table: 5.4.1EFFECT: Rejection due to wrong clamp fitting
(direction)
Sr.
NoParameters Cause: 01 Cause: 02 Cause: 03
1. PeopleInexperience
worker
difficulty in
identification due
Very similar looking
clamp LH & RH
Burdon on
worker due to
recitative task in
short time
2. Material
Only LH or RH
side clamp
available /
purchased
No color coding or
demarcation on
clamp
-
3. Equipment Manual fitting
No separate bins to
store LH & RH
clamp
-
4. Method
Storage clamps
RH &LH) on same
side only
- -
5. EnvironmentLess space for
fitting area- -
From the above table the fishbone diagram or the cause and effect diagram will
be constructed. The skeleton of the fishbone, has different parts that are reserved for the
different parameters that will lead to come across the cause of the failure. The mainspine of the fishbone should be used to show the main failure for which the fishbone is
being constructed. Along the spine bone, of the fishbone, various other bones are
connected, which will be drawn as the branches that will indicate the main parameters
that are contributing to the fishbone. Some of them are people, material, equipment,
method, and environment. The sub branches which are attached to branches that are
drawn earlier will indicate the main causes that are being contributed to the failure to the
medium of parameters.
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5.18
The Cause & Effect Analysis of the main failure, i.e. wrong clamp fitting, gives
us the main parameters, causes, etc., of the failure, causing it to happen. After the Cause
& Effect Analysis, it is necessary to perform the FMEA, to eradicate the problem.
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5.19
Figure 5.4.1 Fishbone for the Rejection due to Wrong Clamping
5.4.1 Customizing FMEA as a Problem Solving Tool
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5.20
To start FMEA, the main requirement is the cross functional team, and some of
the experts that are require, who are involved in the process, causing these failure. A
sample sheet of FMEA in this process is prepares and is given in the Table 5.3.2
Table 5.4.1.1 FMEA sample sheet
The parameters which were defined in the Fishbone diagram, has been classified
according to the department. The department classification of the parameters, makes it
easy to identify, the cause that is related and plays an important role causing the problem,
as the problem gets restricted to only one department.
The failure mode for the particular department is identified, and the effect of that
failure mode is decided, henceforth. The severity, occurrence and detection is rated by
the brain storming sessions, and the RPN is calculated which is the product of Severity,
Occurrence and Detection.
In analysis, the acceptance or the rejection of the process is taken care off, in
which the processes with more than 200 RPN is not acceptable and needs to be
controlled. The control, action or the actions which are taken to reduce the failure are
introduced and applied for the process with higher RPN only, i.e. about 200. A detailed
FMEA is done and shown in Table 5.3.2
CategoryFailure
ModesEffects Severity Probability Detection RPN Analysis
Action
to
reduce
failure
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5.
21
Table5.4.1.2FMEAbasedontheFishbon
eDiagramofrejectsduetowrongclamp
ing
Category
FailureModes
Effects
Severity
Probability
Detection
RPN
Analysis
Actiontored
ucefailure
Delayinfitting
4
3
2
24
Accept
People01
(Manufacturin
g)
Workerdonthaveknowledgeof
clamp-LH&RHside
Wrongclampfitting
10
3
6
1
80
Control
Alwaysdeploytrainedworkersfor
thejob
People02
(Manufacturin
g)
difficultyinidentificationdueVery
similarlookingclampLH&RH
Wrongclampfitting
10
7
6
4
20
Control
1.Usecoloredbins
tostoreclamps
i.e.Red-LH&Blue-RH
2.Displayvisualsf
orright/wrong
fitting
Delayinwork
4
4
2
32
Accept
People03
(Manufacturin
g)
Burdononworkerduetorepetitive
taskinshorttime
Wrongclampfitting
10
2
6
1
20
Accept
People01
(QC)
Workerdonthaveknowledgeof
clamp-LH&RHside
Wrongclampfitting/dispatched
10
3
9
2
70
Control
Alwaysdeploytrainedworkersfor
thejob
People02
(QC)
difficultyinidentificationdueVery
similarlookingclampLH&RH
Wrongclampfitting/dispatched
10
7
9
6
30
Control
Displayvisualsfor
right/wrong
fitting
Assemblystoppage
4
2
2
16
Accept
Material01
OnlyLHorRHsideclampavailable
/
purchased
Fittingofsameclamponboth
side
10
2
2
40
Accept
Material02
Nocolorcodingordemarkingon
clamp
Fittingofsameclamponboth
side
10
7
7
4
90
Control
Usecoloredbinsto
storeclamps
i.e.Red-LH&Blue-RH
Equipment01
Manualfitting
Moretimetofitclamps
4
2
2
16
Accept
Equipment02
NoseparatebinstostoreLH&RH
clamp
Wrongclampfitting
10
9
7
6
30
Control
SeparatebinsforLH&RH
Method
Storageofclamps(RH&LH)onsam
e
sideonly
Wrongclampfitting
10
5
7
3
50
Control
Prepareassemblya
reainsucha
waythatonLHsideofworkerLH
clampbinandRHsideRHclamp
bin
Environment
Lessspaceforfittingarea
Discomforttoworker
4
6
5
1
20
Accept
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5.23
= 6 + 6 + 6 + 8
= 26 minutes.... (i)
1 product takes 26 minutes, so we have 2250 minutes, i.e. essential tomanufacture 86 products per day.
5.5.1.2Calculation based on the capacity of the blow molding machines.One blow molding machine has the capacity of 0.75 tons
Five blow molding machine has an overall capacity of 0.75 x 5 tons, i.e. 3.75
tons
3.75* 907 *1000 grams = 3401250 grams a day
An assembled product weighs 600 grams, so considering 70% material losses,
1700 products considering only the blow molding time, without considering assembly
and with out the extra material removal time + clamp time.
Ideally, one part should require 2 minutes for the blow molding (Considering
the pauses taken for the die introduction and removal process), without considering
assembly and with out the extra material removal time + clamp time.
Considering an average time for the product removal from the Die + Extra
material removal from the part produced + clamping time per part, which can be taken
as 1 minute per operation.
Total time taken per part = blow molding time per part
+ Time for the product removal from the Die
+ Extra material removal from the part produced
+ clamping time per part
= 2 + 1 + 1 +1
= 5 minutes
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5.24
For each product production, i.e. time for production of center duct
+ Left hand side duct,
+ Right hand side duct,
+ Assembly of these parts, requires,
= 5 + 5 + 5 + 8
= 23 minutes. (ii)
Comparing the actual time and the ideal time there is a loss of 3 minutes per
product produced.
I have succeeded in lessening this gap of 3 minutes by 50 seconds, by different
methods introduced which will be discussed later, in this chapter.
By reducing 50 seconds now, my product will be ready in 25 minutes 10
seconds,
1 product will be produced in 25 minutes 10 seconds, so 2250 minutes will
produce 90 final products, i.e. increment of 4 products per day.
Increment of 4 product per day implies, in a month with 25 working days, will
yield 100 products per month as an increment, which further implies, 1200 product a
year increment.
The savings of 50 seconds per product will yield approximately around 0.18
million of rupees to the company annually.
5.5.2 Points applied, for 50 seconds reduction in total time, for the completemanufacturing of the Air Duct.
1. Implementing the FMEA has also helped in reducing the time, byreducing the potential failures.
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5.25
Reduction of rejects from in process inspection and finalinspection, results in to less re work, and time saving in achieving
the targets.
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5.26
Table 5.5.1 FAILURE MODE AND EFFECT ANALYSIS
e Modes Effects Severity Probability Detection RPN
arameters setting
machine
Defected first piece produced,
then re setting of parameters
8 3 5 120
per die settingDefected first piece produced,
then re setting of parameters10 2 5 100
material removaldefected first piece produced,
then re setting of parameters7 5 5 175
ting rejection and rework 5 8 3 120
rejection and rework 10 2 2 40
e Damage or brakage 4 3 2 24
Raw materialRejection 8 3 8 192
age rejection and rework 5 8 3 120
ue used rejection and rework 5 8 3 120
arameters settingmachine
nnel)
Defected first piece produced,
then re setting of parameters8 3 5 120
ed (Die personnel)Defected first piece produced,
then re setting of parameters
10 2 5 100
ownPersonnel)
Delay in production (production
Personnel)10 2 2 40
arameters settingmachine
nnel)
Defected first piece produced,
then re setting of parameters8 3 5 120
blow moldingtion Personnel)
machine breakdown and delay in
production (maintenance
personnel)
10 2 2 40
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5.28
o Weekly financial appraisalo Appraisal according to the number of product produced
after the target is achieved in the day
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