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Lampiran 1 Penjelasan hubungan antar pemborosan (waste)
O_I : Over production comsumes and needs large amounts of raw material causing stocking of raw material and producing more work-in process that consume floor space, and are considered as a temporary form of inventory that no customer (process) that may order it O_D : When operators are producing more, their concern about the quality of the parts produced will decrease, because of the senses that there exists enough material to substitute the defect
O_M : Over production leads to non ergonomic behavior, which leads to non standardized working method with a considerable amount of motion losses.
O_T : Over production leads to higher transportation effort to follow the overflow of materials O_W : When producing more, the resources will be reserved for longer times, thus other
customer will be waiting and larger queues to form.
I_O : The higher level of raw materials in store can push workers to work more, so as to increase the profitability of th company.
I_D : Increasing inventory (RM, WIP, and FG) will increase the probability of become defected due to lack of concern and unsuitable storing conditions.
I_M : Increasing inventory will increase the time for searching, selecting, grasping, reaching, moving, and handling.
I_T : Increasing inventory sometimes block the available aisles, making a production activity more transportation time consuming.
D_O : Over production behavior appears in order to overcome the lack of parts due to defects. D_I : Producing defective parts the need to be reworked means that increased levels of WIP
exist in the form of inventory.
D_M : Producing defects increases the time of searching, selection, and inspection of parts, not to mention that reworks station will increase transportation intensity (back streams) i.e. wasteful transportation activites.
D_W : Reworks will reserve workstations so that new parts will be waiting to be processed. M_I : Non standardized work method lead to high amounts of work in process,
M_D : Lack of training and standardization means the percentage of defects will increase. M_P : When jobs are non standardized, process waste will increase due to the lack of
understanding the available technology capacity.
M_W : When standards are not set, time will be consumed in searching, grasping, moving, assembling, which result in an increase in part waiting parts.
T_O : Items are produced more than needed based in the capacity of the handling system so as to minimize transportating cost per unit.
T_I : Insufficient number of material handling equipment (MHE) leads to more inventory that can affect other processes.
T_D : MHE plays a considerable role in transportation waste. Non suitable MHE can sometimes damage items that and being defect.
T_M : When items are transported anywhere this means a higher probability of motion waste presented by double handing and searching.
T_W : If MHE is insufficient, this means that items will remain idle, waiting to be transported. P_O : In order to reduce the cost of an operation oer machine time, machines are pushed to
operate full time shift, which finally result in overproduction
P_I : Combining operations in one cell will result directly to decrease WIP amounts because of eliminating buffers.
P_D : If the machines are not properly maintained defects will be produced.
P_M : New technologies of processes that lack training create the human motion waste. P_W : When the technology use is unsuitable, setup times and repetitive downtimes will lead to
higher waiting times.
W_O : When a machine is waiting because its supplier is serving another customer, this machine may sometimes be forced to produce more, just keep it running.
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W_I : Waiting means more items than needed at a certaing point, whether they are RM, WIP, or FG
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Lampiran 2 Pertanyaan kuesioner keterkaitan antar pemborosan Kolom jawaban:
Memilih jawaban a, b, atau c pada no.1-4 dan 6 Memilih jawaban a, b, c, d, e, f, atau g pada no.5
No Pertanyaan Bobot
1 Apakah i mengakibatkan j ?
a. Selalu 4
b. Kadang-kadang 2
c. Jarang 1
2 Apakah tipe keterkaitan antara i dan j?
a. Jika a naik, maka b naik 2
b. Jika a naik, b pada level konstan 1
c. Acak, tidak tergantung 0
3 Dampak j dikarenakan oleh i ?
a. Terlihat langsung dan jelas 4
b. Butuh waktu agar terlihat 2
c. Tidak terlihat 0
4 Bagaimana cara mengeliminasi akibat i terhadap j ?
a. Melalui metode teknik 2
b. Melalui metode sederhana dan langsung 1
c. Melalui metode solusi instruksi 0
5 Dampak j dikarenakan oleh i, berpengaruh pada :
a. Kualitas produk 1
b. Produktivitas 1
c. Waktu tunggu 1
d. Kualitas dan produktivitas 2
e. Produktivitas dan waktu tunggu 2
f. Kualitas dan waktu tunggu 2
g. Kualitas, produktivitas, dan waktu tunggu 4
6 Pada tingkat apa i berdampak pada j dalam meningkatkan waktu tunggu? a. Tingkat tinggi 4 b. Tingkat menengah 2 c. Tingkat rendah 0 Keterangan : i merupakan pemborosan 1 j merupakan pemborosan 2 contoh : Over production_Inventory i = Over production j = Inventory
25 Lampiran 3 Jawaban kuesioner keterkaitan pemborosan dan konversi
No Hubungan antar pemborosan Jawaban dari pertanyaan Jumlah Konversi 1 2 3 4 5 6 1 Over production_Inventory 2 2 4 0 4 2 14 E 2 Over production_Defect 1 0 2 0 4 2 9 I 3 Over production_Motion 4 0 2 0 1 2 9 I 4 Over production_Transportation 4 2 4 0 4 4 18 A 5 Over production_Waiting 4 0 4 0 4 4 16 E 6 Inventory_ Over production 1 2 0 0 4 4 11 I
7 Inventory_Defect 2 0 2 1 2 2 9 I 8 Inventory_Motion 1 0 2 1 4 2 10 I 9 Inventory_Transportation 1 2 4 0 1 2 10 I 10 Defect_Over production 1 0 0 0 4 0 5 O 11 Defect_Inventory 1 0 2 2 2 4 11 I 12 Defect_Motion 2 0 2 1 2 4 10 I 13 Defect_Transportation 1 0 4 0 2 4 11 I 14 Defect_Waiting 2 0 4 0 4 0 10 I 15 Motion_Inventory 2 0 0 0 1 0 3 E 16 Motion_Defect 1 0 4 0 4 0 9 I 17 Motion_Waiting 1 0 4 2 4 4 15 E 18 Motion_Process 2 2 2 0 2 4 12 I 19 Transportation_Over production 2 0 2 1 4 4 13 E 20 Transportation_Inventory 2 0 4 0 4 4 14 E 21 Transportation_Defect 2 0 0 0 1 2 5 O 22 Transportation_Motion 4 0 4 2 2 2 14 E 23 Transportation_Waiting 1 2 4 0 4 4 15 E 24 Process_Over production 1 2 2 0 4 4 13 E 25 Process_Inventory 1 0 2 0 4 2 9 I 26 Process_Defect 1 0 2 2 2 4 11 I 27 Process_Motion 4 2 4 2 4 2 18 A 28 Process_Waiting 2 0 1 2 4 4 13 E 29 Waiting_Over production 2 0 2 1 2 2 9 I 30 Waiting_Inventory 1 2 4 2 4 2 15 E 31 Waiting_Defect 1 0 2 2 4 4 13 E
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Lampiran 4 Pembobotan awal pertanyaan WAQ berdasarkan WRM
No Aspek
pertanyaan Jenis pertanyaan
Bobot awal untuk setiap jenis waste
O I D M T P W