Upload
le-ban
View
215
Download
0
Embed Size (px)
Citation preview
8/6/2019 1 Ban Hiep Lens MPL Term Project AITVN
1/14
Term project: Solution for delayded delivery of Eyeglass lens manufacturing 1
Subject: Modern Production Logistic
Term Project:
SOLUTION for DELAYED
DELIVERY OF EYEGLASS LENS
MANUFACTURING
Subject: Modern Production Logistic
Students:
LE NGOC BAN (Mr)
NGUYEN THI MY HIEP (Ms)
Instructor: Prof.Voratas Kachitvichyanukul
8/6/2019 1 Ban Hiep Lens MPL Term Project AITVN
2/14
Term project: Solution for delayded delivery of Eyeglass lens manufacturing 2
Subject: Modern Production Logistic
TABLE OF CONTENTS
I. Statement of the problem. ........................................................................................... 3
II. Objective of project ..................................................................................................... 3
III. Methodology. ............................................................................................................ 3
1. Root cause analysis ................................................................................................ 3
2. Eyeglass lens manufacturing diagram and process data: ....................................... 4
3. Methodology. ......................................................................................................... 5
a) Sale forecast for the year of 2011. ...................................................................... 5
b) Methodology. ...................................................................................................... 8
IV. Analysis of result ..................................................................................................... 12
V. Conclusion and Recommendation: ........................................................................... 13
1. Conclusion: .......................................................................................................... 13
2. Recommendations: ............................................................................................... 14
8/6/2019 1 Ban Hiep Lens MPL Term Project AITVN
3/14
Term project: Solution for delayded delivery of Eyeglass lens manufacturing 3
Subject: Modern Production Logistic
I. Statement of the problem.Eyeglass lens manufacturing company is in a state of delayed delivery, we are
hired as a consultant group to determine the root cause of the problem and to find a
remedy to improve this situation. Base on the historical sale report and by using a
fishborn diagram, we found the root cause and proposed a best solution to help the
factory deal with their problem.
II. Objective of projectThe first priority is to determine the root cause that made the company fall in
delayded delivery situation, after the cause was found, combining with the historical
report, we give them the best solution and more than that we provide insight to operate
the plant with maximizing throughput.
III. Methodology.1. Root cause analysisBase on the information that was given from the plant and by using the fishborn
diagram method, we conclude that the problem of delayded delivery is due to poor
production planning.
Delayded
delivery
Mis- schedulin
Product shortage
Poor lo istic
Poor forecast
Poor production plan
8/6/2019 1 Ban Hiep Lens MPL Term Project AITVN
4/14
Term project: Solution for delayded delivery of Eyeglass lens manufacturing 4
Subject: Modern Production Logistic
2. Eyeglass lens manufacturing diagram and process data:Process diagram:
Process data:
Step
Time Lense (Pairs/Hour)
Mould Preparation 3.0 minutes/Rack 240Clean Moulds 3.4 minutes/Rack 212Dry Moulds 1.3 minutes/Rack 554Assemble Moulds
-Gasket (more
expensive) 1.3 minutes/Rack 554-Tape (Cheaper) 4.8 minutes/Rack 150
Install Clamp 30 seconds/Rack 1440Fill with Polymer 40 seconds/Rack 1080Bake 20 hours/Rack 160Cool down 4 minutes/Rack 180Disassemble 2.2 minutes/Rack 327Clean and Inspect 4.0 minutes/Rack 180Annealing 3 Hours/Rack 266Measure & Pack 8 minutes/Rack 90
23.5 hours/Rack 90
8/6/2019 1 Ban Hiep Lens MPL Term Project AITVN
5/14
Term project: Solution for delayded delivery of Eyeglass lens manufacturing 5
Subject: Modern Production Logistic
There are some technical information from subject given:
There are a total of 6 ovens. The capacity of the oven is 600 pairs and the policy isto fill the oven to capacity before starting.
The lens are removed from the oven and cooled rack by rack. The oven is occupied when the first rack is loaded but the bake process cannot
start until the oven is filled.
The oven is freed when all racks of lenses are removed. The annealing oven has unlimited capacity. It is preferable to assemble moulds by using gasket. Tape is used only when there
is no gasket available to be used.
3. Methodology.From the data record of the monthly sales for the past three years, we forecast
demand of product for the next year and our target is to meet this demand by providing
the best production planning.
a) Sale forecast for the year of 2011. Past sales record:
Pairs of Lenses
2008 2009 2010
Jan 24596 27082 29788
Feb 19712 21714 23914
Mar 21692 19624 23804
Apr 20042 22044 24310
May 21516 23738 26180
Jun 22396 24662 20372
Jul 33638 37026 40788Aug 30008 33066 36300
Sep 25520 30116 29931
Oct 17688 19492 18123
Nov 21010 23100 25388
Dec 21890 24090 26422
Total 279708 305754 325320
8/6/2019 1 Ban Hiep Lens MPL Term Project AITVN
6/14
Term project: Solution for delayded delivery of Eyeglass lens manufacturing 6
Subject: Modern Production Logistic
Sesonal index table :Pairs of Lenses
2008 2009 2010 Monthly average Seasonal index
Jan 24596 27082 29788 27155 1.073
Feb 19712 21714 23914 21780 0.861
Mar 21692 19624 23804 21707 0.858
Apr 20042 22044 24310 22132 0.875
May 21516 23738 26180 23811 0.941
Jun 22396 24662 20372 22477 0.888
Jul 33638 37026 40788 37151 1.468
Aug 30008 33066 36300 33125 1.309
Sep 25520 30116 29931 28522 1.127Oct 17688 19492 18123 18434 0.729
Nov 21010 23100 25388 23166 0.916
Dec 21890 24090 26422 24134 0.954
Total 279708 305754 325320
Yearly
Average23309 25480 27110 25300
Applying the Winters forecast method with Alpha: 0.7; Beta: 0.53 and Gamma:
0.2, we forecast Ft (total demand of 2011) approximately equal to 374525 pair of lens.
With the alpha, Beta and Gamma above, we got TS = 0.09 is the minimum value.
In theory, TS ranging from positive 1 to minus 1, TS here is very small compared with 1,
so this result is acceptable.
The monthly demand forecast of 2011
8/6/2019 1 Ban Hiep Lens MPL Term Project AITVN
7/14
Term project: Solution for delayded delivery of Eyeglass lens manufacturing 7
Subject: Modern Production Logistic
Demand forecast year of 2011 compare with last 3 years
30560
24713 2486426117
2855227230
46410
41905
36673
23999
3088032622
0
5000
10000
15000
20000
25000
30000
35000
40000
45000
50000
1 2 3 4 5 6 7 8 9 10 11 12
Monthly Demand 2011
Monthly Demand Monthly average: 31210.
0
20000
40000
60000
80000
100000
120000
140000
160000
180000
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Year 2011
Year 2010
Year 2009
Year 2008
8/6/2019 1 Ban Hiep Lens MPL Term Project AITVN
8/14
Term project: Solution for delayded delivery of Eyeglass lens manufacturing 8
Subject: Modern Production Logistic
b) Methodology.In detail, well solve the problem as following steps:
Forecasting the next year demand 2011 from the record data of the monthly salesfor the past three years 2008, 2009, 2010 that we already have done above.
Calculating the amount of lens needs to be produced a day to meet the demand. Planning of production in detail for each stage, every hour, every day, month and
year to ensure optimal production.Nghec ng m
Re-check the production plan that satisfies:Delivering goods on time, adequate output to the customer.
Reduce inventory in the stock.
The working schedules are reasonable, optimal.
Not only planning production to meet market demand, distribution goods on timein 2011, but also need to advise the ability to maximize the plant throughput in the
future.
Year 2011 forecast demand is 374 525 pairs per year equal to 1440 pairs per day
with suppose that the plant runs 5 days per week and 52 weeks per year. Based on data
forecast for year 2011, average amount needs to be produced is 1440 pairs of lens per
Year 2008:
279708Year 2009: 305754
Year 2010:
325320
Year 2011:
374525
8/6/2019 1 Ban Hiep Lens MPL Term Project AITVN
9/14
Term project: Solution for delayded delivery of Eyeglass lens manufacturing 9
Subject: Modern Production Logistic
day. With the global bottleneck capacity of production line of Measure & Packing is 90
pairs of lens per hour, if we work 8 hours per day the amount will be 720 (90 multiply by
8) pairs of lens per day. This amount is a haft of demand requirement which is less than
the requirement so we should arrange the production plan in order to ensure demand perday, that means well supply the finished goods on time. Because of capacity of each
stage is fixed so we choose to increase the number of working hours for Measure &
Packing up to double of 16 hours per day. With the production planning for Measure &
Packing stage of 90*16 = 1440 pairs of lens per day, other stages are always satisfy this
capcity.
Exactly, from the production line, we divide the line into two loops: first loop
from beginning to Baking; and second loop after Baking to the end. From the global
bottleneck capacity of 90 pairs of lens of second loop, firstly we calculate production
planning for the 2nd
loop .
We have production planning of 2nd
loop to get 1440 pairs of lens/day as below:
Time Loop 2 (after baking)
Time inorder
InputFrom
loop 1
Cool
Down
Disass
embly
Clean &
Inspection
Preapare
forannealing
Anneal
Measure
&Package
End
Products
180 327 180 266 90
0 1440 720
1 1260 180 180 180 180
720
90 90
2 1080 180 180 180 360 90 180
3 900 180 180 180 540 90 270
4 720 180 180 180 720 90 360
5 540 180 180 180 180
720
90 450
6 360 180 180 180 360 90 540
7 180 180 180 180 540 90 630
8 0 180 180 180 720 90 720
9 90 810
10 90 900
11 90 99012 90 1080
13 90 1170
14 90 1260
15 90 1350
16 90 1440
Total 1440 1440 1440 1440 1440 1440
8/6/2019 1 Ban Hiep Lens MPL Term Project AITVN
10/14
Term project: Solution for delayded delivery of Eyeglass lens manufacturing 10
Subject: Modern Production Logistic
From the table above, we see the stages of Cool Down, Disassemly, Clean &
Inspection, Annealing will run 8 hours per day, but Measure & Packing will run 16 hours
per day, and well get 1440 pairs per day to suply on time.
Now we consider production planning of 1st
loop:
We have the bottleneck rate of 1st
loop is rb = 212 pairs per hours of Cleaning
stage, if we work 8 hours per day so the production amount of 1st
loop will be 212 x8 =
1696 pairs per day. This value is higher than the nescessary input of 2nd
loop (1440 pairs
per day) so we should control how many pairs should be produced per day, may be two
Ovens run to get 600 pairs x 2=1200 pairs per day or may be three Ovens run to get 600
pairs x 3 = 1800 pairs per day, we calculate to optimize the number of Ovens need to be
run per day in a week as below:
1 st Loop Bake 2 rd Loop
Time of
working/day
(h)
ProductionInventory
(+/- )WIP
Number of
OvensInventory
(+/- )
Input
to loop 2
Monday 8 1696 1800+ 104 3 1440
Tuesday 8 1696 - 496 1200 2 360 1440
Wednesday 6.15 1304 +496 1800 3 120 1440
Thursday 5.66 1200 0 1200 2 480 1440
Friday 6.15 1304 1200-104 2 240 1440
Monday 0 1440
From the table above, we see:
On Monday, we run full time of 8 hours per day to produce 1696 pairs, add 104pairs produced excess from last Friday to have total of 1800 pairs, so we run 03
Ovens on Monday.
On Tuesday, we run full time of 8 hours per day to produce 1696 pairs, but set tobake only 1200 pairs to agree with capacity of loop 2 on next day; 496 pairs left
will be added in production amount of Wednesday.
On Wednesday, we run 6,15 hours is enough, the correlative amount produced is1304 pairs per day, add 496 pairs produced excess from last Tuesday to have total
of 1800 pairs, so we run 03 Ovens on Wednesday.
8/6/2019 1 Ban Hiep Lens MPL Term Project AITVN
11/14
Term project: Solution for delayded delivery of Eyeglass lens manufacturing 11
Subject: Modern Production Logistic
On Thursday, we run 5,66 hours, correlative amount produced is 1200 pairs perday and we run two Ovens on Thursday.
On Friday, we run 6,15 hours , the correlative amount produced is 1304 pairs perday, but set to bake only 1200 pairs to agree with capacity of loop 2 on next day;
104 pairs left will be added in production amount of next Monday. And now you
know why we can run 03 ovens from 104 pairs extra from Friday.
For detail, we make the production time scheduling for the first loop as below:
Time
in
order
Capacity
pairs/hPreparation
Clean Dry AssembleInsta
ll
Fill
Polyme
Cumu
lativeBake
212 554 554 1440 1080
0 8AM 0 0 0 0 0 0 0
6001 9AM 212 212 212 212 212 212 212
2 10AM 212 212 212 212 212 212 424
2,83 10h50' 176 176 176 176 176 176 600
3 10h60' 36 36 36 36 36 36 36
600
4 12AM 212 212 212 212 212 212 248
13PMLunch
break
5 14PM 212 212 212 212 212 212 460
5,66 14h39' 140 140 140 140 140 140 600
6 14h60' 72 72 72 72 72 72 72
600
6,15 15h9' 32 32 32 32 32 32 104
7 15h60' 180 180 180 180 180 180 284
8 17PM 212 213 214 215 216 217 496
29' 29' 104 104 104 104 104 104 600
According to above production time scheduling, we see:
Monday and Tuesday, we have to work 8hours per day that we product 1696 pairsper day.
Wednesday and Friday, we have to work 6,15 hours per day, so we stop workingat stages at 15h9PM to get 1304 pairs per day before Baking.
8/6/2019 1 Ban Hiep Lens MPL Term Project AITVN
12/14
Term project: Solution for delayded delivery of Eyeglass lens manufacturing 12
Subject: Modern Production Logistic
Thusday, we have to work 5,66 hours per day, so we stop working at stages at14h39PM, to get 1200 pairs per day, before Baking.
We can devide production calendar as below:
Day in week
1st loop Bake 2nd loop
Mould
Preparatio to
Fill Polyme
Cool down to
Cleanning &
Inspec
AnneallingMeasure
& Packing
Monday 8:00 - 17:00
12:00-8:00
15:00-11:00
17:00-13:00
8:00 - 17:008:00-11:00
13:00 -16:00
8:00-17:00
20:00-5:00
Tuesday 8:00 - 17:0012:00-8:00
15:00-11:008:00 - 17:00
8:00-11:00
13:00 -16:00
8:00-17:00
20:00-5:00
Wednesday 8:00 - 15:09
12:00-8:00
15:00-11:00
17:00-13:00
8:00 - 17:008:00-11:00
13:00 -16:00
8:00-17:00
20:00-5:00
Thursday 8:00 - 14:3912:00-8:00
15:00-11:008:00 - 17:00
8:00-11:00
13:00 -16:00
8:00-17:00
20:00-5:00
Friday 8:00 - 15:0912:00-8:00
15:00-11:008:00 - 17:00
8:00-11:00
13:00 -16:00
8:00-17:00
20:00-5:00
Monday 8:00 - 17:00
12:00-8:00
15:00-11:00
17:00-13:00
8:00 - 17:008:00-11:00
13:00 -16:008:00-17:0020:00-5:00
IV.
Analysis of result
According to the scheduled working calendar above, the plant can produce 374400
pairs of lens per year. Meanwhile, annual demand forecast 2011 around : 374525 pairs of
lens per year, the deviation between quantity of production and demand is negligible, so
this production capacity is acceptable.
8/6/2019 1 Ban Hiep Lens MPL Term Project AITVN
13/14
Term project: Solution for delayded delivery of Eyeglass lens manufacturing 13
Subject: Modern Production Logistic
Meet demand of the year 2011 with:- 1st loop: working from 8 am to 5 pm everyday to run 2 or 3 oven/day- 2nd loop: working from 8 am to 5 pm everyday, except Mrs&Pack works
16hours per day.
- Bake: running 20 hours- Only Measure&Pack process needs 2 working shifts.- 1st loop has no need to be operated all entire 2011.- Only 3 out of 6 ovens needed at Bake at 80C process
Production plan scheduled Delayed delivery solved, customer service is satisfied
The problem of delayded delivery was solved. But, be aware of critical monthly
demand during the year of 2011, from the monthly forecast diagram the highest demand
period is from July to September. To offset this peak, the plant have to make to stock
from January to June.
Solution for maximizing the plant throughput:
Cycle WIP = 7200 pairs per week. Cycle time = 123 hours
From the Littles law Throughput = , we get:
Throughputactual = 7200/123 = 58.53 pairs per hour. Throughputbest case = rb = 90 pairs per hour. ThroughputPWC = +1 = 69.57 pairs/h, where Wo = rb * To = 90*23.5 = 2115
Throughputactual < ThroughputPWC, So still room for improvement.
V. Conclustion and Recommandation:1. Conclustion:
8/6/2019 1 Ban Hiep Lens MPL Term Project AITVN
14/14
Term project: Solution for delayded delivery of Eyeglass lens manufacturing 14
Subject: Modern Production Logistic
The problem of delayded delivery was solved with the strict timely workingcalendar required
Steady-state assumed Unable to improve the bottleneck speed Unlimited mould supply Unlimited gasket supply 12:00 13:00 is a lunch break Throughput can be improved for greater demand of the next years.
2. Recommendations: Logistics system should be checked. Forecast system should be checked. Capacity of Measure&Pack process should be improved. Hidden capacity in many processes can be yielded in the future.
The end!