PERENCANAAN AGREGAT (DISAGREGASI) & TEORI KAPASITAS Kuliah 4 LSiPro – FT Untirta Muhammad Adha Ilhami 3rd Edition 2014 Muhammad Adha Ilhami

Tujuan Pembelajaran Mahasiswa mampu menggunakan teknik disagregasi Mahasiswa mampu menyusun Master Production Schedule (MPS) atau Jadwal Induk Produksi (JIP). Muhammad Adha Ilhami

Definisi Work Center Section of a production facility where all task associated with a particular process (such as assembling, painting, welding) are performed. It usually has more than one machine. Sumber: http://www.businessdictionary.com/definition/work-center.html#ixzz11xhyQTXS Muhammad Adha Ilhami

Ilustrasi Work Center Welding Work Center Assembly Work Center WELDING CUTTING MACHINE WELDING CIRLING MACHINE SAFETY EQUIPMENT Main Assembly Table Support Assembly Table Welding Work Center Boxes Assembly Work Center Muhammad Adha Ilhami

Workstation Assigned location for an employee to perform his or her job, and which is equipped with all the required tools and facilities. It usually has one main working component. It is specifically dedicated to one employee only. Workstations are commonly networked together. Muhammad Adha Ilhami

Workstation Illustration Main Machine Incoming WIP Outgoing WIP Muhammad Adha Ilhami

Takt Time Takt Time = Total Daily Operating Time / Total Daily Customer Requirements Where Operating Time does not include TPM, 5S, meeting times, breaks, etc… So… Takt time is calculated and not measured. It can help to determine process capabilities Contoh: Customer A requires 5000 pieces per week or 1000 pieces per day. Operating time is 8 hours – breaks = 7,5 hours/shift Tak time = (7,5 hours x 3600 seconds/hours) / (1000 pieces) = 27 seconds/piece Muhammad Adha Ilhami

Definisi Kapasitas the rate of output from an OM system per unit of time the rate at which the firm withdraws work from the system Jumlah masukan sumberdaya-sumberdaya yang tersedia relatif untuk kebutuhan keluaran pada waktu tertentu. Satuan unit : jumlah/waktu atau waktu/unit Muhammad Adha Ilhami

Definisi Kapasitas Produksi In general, production capacity is the maximum production rate of an organization (or maximum conversion rate of a production system) in any given period. Sustainable practical capacity is the greatest level of output that a plant can maintain: within the framework of a realistic work schedule taking account of normal downtime assuming sufficient availability of inputs to operate the machinery and equipment in place Muhammad Adha Ilhami

Definisi Macam-Macam Kapasitas (1) Design Capacity : tingkat keluaran per satuan untuk mana pabrik dirancang. Rated Capacity ; tingkat keluaran per satuan waktu yang menunjukkan bahwa fasilitas secara teoritik mempunyai kemampuan memproduksi. Standard capacity : tingkat keluaran per satuan waktu yang ditetapkan sebagai sasaran pengoperasian bagi manajemen, supervisi dan para operator mesin, dapat digunakan sebagai dasar bagi penyusunan anggaran. Muhammad Adha Ilhami

Definisi Macam-Macam Kapasitas (2) Actual dan atau operating capacity : tingkat keluaran rata-rata per satuan waktu selama periode waktu yang telah lewat = kapasitas standar ± cadangan-cadangan, penundaan, tingkat sisa nyata. Peak capacity : jumlah keluaran per satuan waktu yang dapat dicapai melalui maksimisasi keluaran dengan kerja lembur, menambah tenaga kerja, mengurangi jam istirahat dan sebagainya. Muhammad Adha Ilhami

How a plant/system is organized Level of output of a plant or system is dependent on how it is organized capacity in sequence: linear operations, is based on the operation with the lowest amount of capacity capacity in parallel: multiple alternative operations any machine can be used Muhammad Adha Ilhami

Capacity in Sequence capacity in sequence: linear operations, is based on the operation with the lowest amount of capacity. Contoh: Operasi 1 : 20 unit/jam Operasi 2 : 10 unit/jam Operasi 3 : 15 unit/jam Maka kapasitas sistem adalah 10 unit/jam Muhammad Adha Ilhami

Capacity in Sequence (Illustration) Meski mampu menghasilkan 15 unit dalam 1 jam. Namun karena hanya ada inputan 10 unit maka dalam 1 jam hanya menghasilkan 10 unit Meski ada inputan 20 unit dalam 1 jam. Stasiun ini hanya mampu menghasilkan 10 unit Dalam 1 jam menghasilkan 20 unit Dalam satu jam hanya akan dihasilkan 10 unit 20/jam 10/jam 15/jam Muhammad Adha Ilhami

Capacity in Parallel capacity that is based on the sum of the capacities of the various machines that make up the operation. Contoh: Operation 3 has 4 machines machine 1 - 90 pieces per minute machine 2 - 110 pieces per minute machine 3 -120 pieces per minute machine 4 - 80 pieces per minute Total capacity for operation 3 = 400 pieces/min Muhammad Adha Ilhami

Capacity in Parallel (Illustration) Dalam satu menit dihasilkan 90/menit 90 unit 90 + 110 + 120 + 80 = 400 unit/menit 110/menit 110 unit 120/menit 120 unit 80/menit 80 unit Muhammad Adha Ilhami

How about this one? 90/menit 100/menit 70/menit ? 110/menit 80/menit 60/menit 120/menit 150/menit 135/menit 80/menit 50/menit 90/menit 18.000 unit / jam Berapa Kapasitas Produksi Sistem ini dalam 1 jam? Muhammad Adha Ilhami

URGENSI DISAGREGASI Disagregasi diperlukan jika peramalan dilakukan dalam unit aggregate, namun jika peramalan tidak dilakukan dalam unit aggregate maka disagregasi tidak diperlukan. Sementara peramalan dalam unit aggregate dilakukan atas dasar simplifikasi (filosofi dari aggregate plan) Muhammad Adha Ilhami

Alur Proses Pengolahan Data – Peramalan – Rencana Agregat Item Family Family Data Data Produk A B C Peramalan Family Perancangan Agregat Disagregasi MPS Agregasi Data Data family A B C Peramalan Family Perancangan Agregat Disagregasi MPS Agregasi Muhammad Adha Ilhami

Perhitungan Persentase (dengan nilai penjualan) Periode Jan Feb Mar Apr Mei Jun Family X (hasil forecast 2010) 200 250 400 210 450 255 Data Penjualan Terdahulu (2009) Jul Agu Sept Okt Nov Dec Demand Records Produk A 100.00 80.00 65.00 180.00 90.00 150.00 Produk B 50.00 Produk C 120.00 115.00 85.00 110.00 300 260 240 340 Muhammad Adha Ilhami

Perhitungan Persentase (dengan nilai penjualan) Produk Harga Periode Jul Agu Sept Okt Nov Dec Total Persentase A 100.00 Demand Records Produk A 10,000.00 8,000.00 6,500.00 18,000.00 9,000.00 15,000.00 66,500.00 0.27 B 200.00 Produk B 16,000.00 13,000.00 20,000.00 85,000.00 0.34 C 150.00 Produk C 17,250.00 12,750.00 16,500.00 97,500.00 0.39   Family X 44,000.00 38,250.00 29,250.00 56,000.00 34,000.00 47,500.00 249,000.00 Disagregasi Hasil Peramalan Periode Jan Feb Mar Apr Mei Jun Family X 200 250 400 210 450 255 Demand Forecast Produk A 53.41 66.77 106.83 56.08 120.18 68.10 Produk B 68.27 85.34 136.55 71.69 153.61 87.05 Produk C 78.31 97.89 156.63 82.23 176.20 99.85 Example : MPS Januari (Produk A) = 200 x 0,27 = 53,41 MPS Januari (Produk B) = 200 x 0,34 = 68,27 MPS Januari (Produk C) = 200 x 0,39 = 78,31 Muhammad Adha Ilhami

Disagregasi Menggunakan Teknik Persentase (dengan pertimbangan nilai conversion) Data Penjualan Terdahulu Periode Jul Agu Sept Okt Nov Dec Demand Records Produk A 100.00 80.00 65.00 180.00 90.00 150.00 Produk B 50.00 Produk C 120.00 115.00 85.00 110.00 Family X 300 260 200 400 240 340 Perhitungan Persentase Produk Waktu Proses Conversion Periode Jul Agu Sept Okt Nov Dec Total % A 74.34 0.61 Demand Records Produk A 61.25 49.00 39.81 110.24 55.12 91.87 407.28 0.32 B 62.32 0.51 Produk B 41.07 33.37 25.67 51.34 218.21 0.17 C 121.38 1.00 Produk C 120.00 115.00 85.00 100.00 110.00 650.00   Family X 222.32 197.37 150.48 281.59 180.79 242.94 1,275.49 Muhammad Adha Ilhami

Disagregasi Menggunakan Teknik Persentase (dengan pertimbangan nilai conversion) Disagregasi (Persentase dari nilai penjualan) Periode Jan Feb Mar Apr Mei Jun Family X 200 250 400 210 450 255 Demand Forecast Produk A 63.86 79.83 127.73 67.06 143.69 81.43 Produk B 34.22 42.77 68.43 35.93 76.98 43.62 Produk C 101.92 127.40 203.84 107.02 229.32 129.95 Example : MPS Januari (Produk A) = 200 x 0,32 = 63,86 MPS Januari (Produk B) = 200 x 0,17 = 34,22 MPS Januari (Produk C) = 200 x 0,51 = 101,92 Muhammad Adha Ilhami

Hasil Disagregasi (MPS/JIP) Master Production Schedule / Jadwal Induk Produksi Periode Jan Feb Mar Apr Mei Jun Demand Forecast Produk A 64 80 128 68 144 82 Produk B 35 43 69 36 77 44 Produk C 102 204 108 230 130 Muhammad Adha Ilhami