Sistem Produksi Tepat Waktu – IND7472Laks – IE UAJY©2010

ALIRAN PRODUKSI &

FASILITASI ALIRAN

Tujuan

Mengetahui dan memahami peran dan

karakteristik aliran produksi yang

diperlukan dalam JIT

Sasaran

• Syarat JIT dalam mencapai aliran proses yang rata

• Karakteristik aliran yang “rata” dan “halus”

• Memahami karakteristik aliran kontinyu pada JIT

• Memahami perbedaan antara tipe aliran batch

(shis kabob) dengan tipe aliran pada JIT

• Memahami pengaruh organisasi fasilitas produksi

terhadap aliran produksi pada JIT

Syarat JIT : Perancangan Aliran Proses

• Hubungan/keterkaitan operasi

• Reduksi ukuran lot/batch

• Laju produksi stasiun kerja seimbang

• Tata letak ulang fasilitas untuk aliran

• Penekanan pada preventive maintenance

• Reduksi setup (changeover time)

Tujuan Fasilitasi Aliran• Fleksibilitas

– Kemampuan organisasi untuk bereaksi terhadap perubahan– Kemampuan untuk bisa memproduksi beberapa jenis

produk pada beberapa urutan• Koordinasi

– Kemampuan menyesuaikan permintaan produk dengan tingkat komponennya dengan penyesuaian terhadap permintaan item yang dependent

• Volume– Konsep simplifikasi dan repetisi

• Visibilitas– Sederhana, sistem pengendalian yang mudah

• Aksesabilitas– Akses proses, peralatan, dan perkakas yang tidak terputus– Pekerjaan dapat mengalir pada jalur yang tidak terhambat

• Disiplin– Sesuatu terjadi dengan cara yang sama, pada waktu yang

sama, setiap waktu

Aliran Terencana

Karakteristik Aliran Terencana

• Smoothly Aliran material rata sepanjang lini produksinya

• BrisklyAliran material yang “rapi” dan “halus”sepanjang lini produksinya

Finished Good Inventory & Smooth Production Activities

Fabrication Subassembly Final Assembly Warehouse Market

FinishedGoods

Inventory

Fabrication Subassembly Final Assembly Warehouse Market

IV.Continuous

Flow

III.Assembly

Line

II.Batch

I.Job

Shop

LowVolumeOne of a

Kind

MultipleProducts,

LowVolume

FewMajor

Products,HigherVolume

HighVolume,

HighStandard-

ization

CommercialPrinter

French Restaurant

HeavyEquipmentCoffee Shop

AutomobileAssembly

Burger King

SugarRefinery

Flexibility (High)Unit Cost (High)

Flexibility (Low)Unit Cost (Low)

Functional Layout dan Flow

L

L

L

L

L

L

L

L

L

LM

M

M

M

D

D

D

D

D

D

D

D

G

G

G

G

G

G

A A AReceiving andShipping Assembly

Painting Department

Lathe DepartmentMilling

Department Drilling Department

GrindingDepartment

P

P

Raw Stock Q C Rec Ship

ShearScrew 

MachineQ C

Stamp

AssemblyBrake MillLathe

Weld FinishGrind Parts Stock

Drill

Value‐Added Time : MinutesTime in Plant :          Weeks

ORDER CASH

Functional Plant Layout

Batch dan Job Shop Production

1

6

3

5

2

4

Batch of part A (route: 1 - 5 - 3 - 4 - 2 - 6)

Batch of part B (route: 4 - 2 - 5 - 6 - 3)

Route part A dan B digambarkan berikut

Aliran Produksi Pada Job Shop(Shish Kabob)

Saw

Saw

Lathe

Lathe

Mill

Paint

Paint

Grinde

r

Assembl

y

Assembl

yPlating

Building Service

Storage

Missc.

Assembly

: Material Flow

: Material Flow

Saw

Mill

Paint

Grinde

r

Plating

Supplier – Production –Distribution System

Supplier DistributionInventories

Raw materialin-transit

Sub-assemblyparts in-transit

Maintenance,repair, and orderingsupplies in-transit

Raw MaterialInventory

Work-in-processInventory

FactoryFinished

GoodsInventory

ComponentInventory

MROInventory

PurchasingProduction and

Inventory ControlShipping and

Traffic

RetailerInventory

Orders

WarehouseInventory

Productions InventoriesCustomer

DistributionInventories

Orders

Continuous Flow(Aliran Kontinyu)

Produksi dan pergerakan satu item pada suatu waktu(atau batch/lot item yang kecil dan konsisten) melalui serangkaian tahapan proses secara kontinyu(sekontinyu mungkin), dengan setiap tahapan menghasilkan apa yang diminta oleh tahap berikutnya.

Hal ini juga disebut:– one-way product flow– one-piece flow– single-piece flow– make one– move one

Flow Production(Continuous Flow)

• Pada mekanisasi flow line, semua operasi digerakkan oleh laju lintas produksi.

• Tidak ada operasi dapat menghasilkan lebih daripada diperlukan oleh operasi downstream berikutnya.

• Hal yang tidak mungkin untuk membentuk WIP.

Gambaran Continuous Flow Production

Flow with JIT

Traditional Flow

CustomersSuppliers

Customers

Suppliers

Production Process

(stream of water)

Inventory (stagnant ponds)

Material(water in stream)

Perubahan Batch Production keFlow Production

• Pada produksi massal, batch/lot tidak teratur menghasilkan aliran produksi yang beragam dan rendah kinerjanya.

• Efisiensi Aliran Produksi dapat dicapai melalui:

– small-lot production

– uniform production schedules

Karakteristik Shish Kabob & Flow Production

Karakteristik Shish Kabob& Flow Production (lanjutan)

Point ComparisonType of production

Shish-kabob production Flow production

Profiency Worker repeats the same operation

Worker repeats a group of operations

In-process inventory

A lot Almost none

Lead-time Long Short

Equipment High-speed, general purpose, large, costly, emphasis on capacity utilization

Slow, specialized, small, inexpensive, emphasis capacity utilization

Production orientation

Narrow variety and large lots Wide variety and small lots

Space Takes up a lot of space Does not take up as much space

Approach to Efficiency

Emphasis of efficiency within process

Emphasis of efficiency within process

Conveyance Required Not required

Quality Quality problems discovered only after the lot is prouce

Minimization of defects that cause quality problem

Pengaruh Layout dan Ukuran Lot pada Waktu Operasi

A B C D

A

A

A

A

B

B

B

B

C

C

C

C

D

D

D

D

Time Elaspe

d (min.)

0

5

10

15

20

Processing Time = 1 min./unit

Process-Oriented Layout with Transfer Lot Size of

Five

5 min.

5 min.

5 min.

5 min.

Time Elasped (min.)

A B C D

A

A

A

A

B

B

B

B

C

C

C

C

D

D

D

D

0

1

2

3

8

Processing Time = 1 min./unit

Product-Oriented Layout with Transfer Lot Size of

One

1 min.

1 min.

1 min.

1 min.

4

A B C D

10 minutes

10 minutes

Batch & Queue Processing

Lead Time 30+ minutes for total order21+ minutes for first piece

10 minutes

ProcessA

ProcessB

ProcessC

ProcessB

ProcessA

ProcessC

Continuous Flow Processing

12 min. for total order3 min. for first part

Dampak Reduksi Ukuran Batch

Batch Size Reduction

The best batch size is one piece flow, or

make one and move one!

Tahap Perencanaan Aliran Tunggal(One‐piece) Flow Production

(4) Create U‐shaped 

manufacturing cells

(6) Synchronization

(5) Multi‐process 

operations

(2) Lay out (line up) equipment according to sequence of processing

(1) Establish one‐piece flow

(3) Standing while working

Train multi‐process w

orkers

Preparation:•Production analysis

•Intall casters on equipment•Select model line

Groundwork:•Awareness revolution

•The 5S’s

The Five Steps of Lean Production/Toyota Production System

Implementation• Step 1: Specify Value

Define value from the perspective of the final customer. Express value in terms of a specific product, which meets the customer's needs at a specific price and at a specific time.

• Step 2: Value Stream Mapping.Identify the value stream, the set of all specific actions required to bring a specific product through the three critical management tasks of any business: the problem-solving task, the information management task, and the physical transformation task. Create a map of the Current State and the Future State of the value stream. Identify and categorize waste in the Current State, and eliminate it!

The Five Steps of Lean Production/Toyota Production System

Implementation• Step 3: Create Continuous Flow

Make the remaining steps in the value stream flow. Eliminate functional barriers and develop a product-focused organization that dramatically improves lead-time.

• Step 4: Create Pull ProductionLet the customer pull products as needed.

• Step 5: PerfectionThere is no end to the process of reducing effort, time, space, cost, and mistakes. Return to the first step and begin the next lean transformation, offering a product which is ever more nearly what the customer wants.

Value Stream Mapping

• A simple diagram of every step involved in the material and information flows needed to bring a product from order to delivery.

• Value stream maps can be drawn for different points in time as a way to raise consciousness of opportunities for improvement.

Value Stream Map Symbols

Spot weld

ABCplating

C/T = 30 sec

C/O = 10 min

3 shifts

2% scrap rate

Process

Finishedgoods

Vendor Data box

3,000 units

= 1 day

Inventory

Push Supermarket: the location of a predetermined

standard inventory

Physical pull

Monand

Wed

Shipment

C/T = Cycle Time

C/O = Change over or setup time

Current Value Stream Map

Future Value Stream Map

Aliran Tunggal Transfer Manual

Aliran Tunggal Multi Proses

U-Shaped Layout

Manufacturing Cell

Contoh Cellular Manufacturing

Functional Layout Cellular Layout

Market Demand = 220,000 Units Per YearTakt Time = 27 Seconds

Lathe Mill Mill InspectDrill

Drill

TestDrillPack

1 2 3 4 5

10 9 8 7

6

27 Seconds 27

Seconds

Inspect

27 Seconds

Cellular Layout

Perbandingan Straight Line dan U Shaped Flow Production

Cellular Layout

Kesimpulan

• Aliran produksi yang rata dan halus terwujud dengan membentuk aliran kontinyu dengan ukuran lot atau batch yang kecil

• Aliran tunggal dan kontinyu merupakan cara dan sekaligus tujuan untuk membentuk sistem produksi yang efisien dan mereduksi bentuk pemborosan dalam hal perpindahan material (moving)

• Tata letak fasilitas yang tepat sangat diperlukan untuk membentuk aliran kontinyu dan tunggal

Malu BertanyaBingung Selamanya