line balancing & worker machine process chart
DESCRIPTION
Line balancingTRANSCRIPT
LINE BALANCING & WORKER AND MACHINE
PROCESS CHART
Definisi Line balancing merupakan suatu metode
penugasan sejumlah pekerjaan yang saling berkaitan dalam satu lini produksi sehingga setiap stasiun kerja memiliki waktu yang tidak melebihi waktu siklus dari stasiun kerja tersebut.
Line balancing berusaha menyeimbangkan seluruh lintasan yang ada dalam lini perakitan sehingga aliran produksi berjalan lancar.
Operator 1 Operator 2
Operator 3
Operator 4
Operator 5
Operator
Standard Minutes
to Perform
Operation
1 0.49
2 0.31
3 0.25
4 0.44
5 0.54
How to Calculate Line Efficiency ?
100
.
..
5
1
5
1 X
MA
MS
E
Operator
Standard Minutes
to Perform
Operation
Wait Time Based on
Slowest Operator
Allowed
Standard
Minutes
1 0.49 0.05 0.54
2 0.31 0.23 0.54
3 0.25 0.29 0.54
4 0.44 0.1 0.54
5 0.54 0 0.54
2.03 2.7
Line Efficiency ?
0.49 0.31
0.25
0.44
0.54
Operator
Standard Minutes
to Perform
Operation
Wait Time Based on
Slowest Operator
Allowed
Standard
Minutes
1 0.49 0.05 0.54
2 0.31 0.23 0.54
3 0.25 0.29 0.54
4 0.44 0.1 0.54
5 0.54 0 0.54
2.03 2.7
Efficiency 75.19%
Opportunities for Improvements ?
Operation Standard Minutes
1 1.5
2 2.25
3 1.25
4 2.5
5 3
6 2.75
7 1.75
Assembly Line
(7 operations)
Desired Rate of Production = 1000/day
Efficiency = 95%
1 day = 10 hours = 600 minutes
Thus R = 1000/600 = 1.67 units/minute
Numbers of Operator Needed
in Assembly Line?
E
SMRAMRN
27 operators
Operation Standard Minutes
1 1.5
2 2.25
3 1.25
4 2.5
5 3
6 2.75
7 1.75
minutes/unit 0.6
∑SM 15
R 1.67
E 0.95
26.36842105
Operation Standard Minutes
(standard
minutes)/(minutes/u
nit)
Operators
1 1.5 2.5 3
2 2.25 3.75 4
3 1.25 2.083333333 2
4 2.5 4.166666667 5
5 3 5 5
6 2.75 4.583333333 5
7 1.75 2.916666667 3
minutes/unit 0.6 27
Output? 1.5/0.6
2.25/0.6
Dst.
600/1000
Slowest One?
Operation Standard Minutes
(standard
minutes)/(minutes/u
nit)
Operators
1 1.5 2.5 3 0.5
2 2.25 3.75 4 0.5625
3 1.25 2.083333333 2 0.625
4 2.5 4.166666667 5 0.5
5 3 5 5 0.6
6 2.75 4.583333333 5 0.55
7 1.75 2.916666667 3 0.583333333
dayhouroutput /1000/1003
605
(2.5/3)*0.6
(3.75/4)*0.6
Dst.
Line Balancing Problem
A
B
C
4.1mins
D
1.7mins
E
2.7 mins
F
3.3
mins
G
2.6 mins
2.2 mins
3.4 mins
• 1. What process is the bottleneck?
• 2. How much is the maximum
production per hour?
• 3. How much the efficiency?
• 4. How to minimize work stations?
• 5. How should they be grouped?
• 6. New efficiency?
Question
Calculate efficiency • A. 73.2%
• B. 56.7%
• C. 69.7%
• D. 79.6%
• E. 81.2%
A
B
C
4.1mins
D
1.7mins
E
2.7 mins
F
3.3
mins
G
2.6 mins
2.2 mins
3.4 mins
(2.2+3.4+4.1+2.7+1.7+3.3+2.6)
4.1x7
20
28.7
69.7%
1-69.7%=30.3% Balance Delay
time cycle
times taskN
(bottleneck)
20
4.1 = 4.88 work stations
Number of Workstation
Line Balancing Solution
A
B
C
4.1
D
1.7
E
2.7
F
3.3
G
2.6
Station 1
Station 2
Station 3
Station 4
2.2
3.4
All under 6 minutes?
(6.0)
(5.6)
(5.8)
4 Stations 20/24=83.3%
Max prod./hour
60/6
10 units/hour
Line Balancing Problem
A
B
C
4.1mins
D
1.7mins
E
2.7 mins
F
3.3
mins
G
2.6 mins
2.2 mins
3.4 mins 5.6
5.0
20/5.6x5 = 20/28 = 71.4%
5 Stations
Max Prod./hour
60/5.6
10.7 units/hour
40 secs
59 secs
84 secs 34 secs
56 secs 45 secs
What is the minimum # of work stations?
Round down.
• 3
• 2
• 4
• 5
• 6
timecycle
task timesN
40+59+84+56+34+45 = 318
318/84 = 3.78 or 3 work stations
What is the efficiency with 6 operators?
100
timecyclestations ofnumber
task times%Efficency
318/6 x 84=
318/504 =
63%
100
timecyclestations ofnumber
task times%Efficency
40 secs
59 secs
84 secs 34 secs
56 secs 45 secs
99 secs
118 secs
3 Stations ?
318/3x118
318/354 = 89.8% 101 secs
40 secs
59 secs
84 secs 34 secs
56 secs 45 secs
4 Stations? 99 secs
84 secs
56 secs
79 secs
318/4 x 99 =
318/396 =
80.3%
Worker and Machine Process Chart
Worker and Machine Process Chart
Definisi dan Kegunaan
Menggambarkan hubungan waktu antara working cycle seseorang dengan operating cycle suatu mesin
membandingkan idle mesin dengan idle pekerja
Worker and Machine Process Chart
Contoh:
man Machine 1 Machine 2
loading loading
idle
walking press
loading loading
walking press
Worker and Machine Process Chart
wl
mlN1
N = jumlah mesin
m = total machine running time
w = walking time
l = loading and unloading time
Worker and Machine Process Chart
• total expected cost (TEC)
1
211 ))((1 N
KNKmlTECN
K1 = operator rate
K2 = cost of machine
))(( 2212KNKwlTECN
Worker and Machine Process Chart
• contoh soal
proses Time (minute)
Pick up plate into press dies 0,1
Lubricate dies in press 0,3
Press 1,2
Walk to next press 0,1
$ worker (K1) = $ 12 / hour
$ machine (K2) = $ 10 / hour
Worker and Machine Process Chart
• Ditanya:
• Jumlah mesin yang dibutuhkan
• TEC tiap kemungkinan jumlah mesin
Jawaban
• N = (l+m)/(l+w) = (0.4+1.2)/ (0.4+0.1) = 3.2
• Sehingga jumlah mesin yang mungkin adalah 3 atau 4 mesin
Jawaban
• TEC3 = (l+m)(K1+n1K2)/n1 = (0.4+1.2)(12+3 x 10)/3/60
= $ 0.3733/ unit
• TEC4 = (l+w)(K1+n2K2) = (0.4+0.1)(12+4x 10)/60
= $ 0.4333 /unit