Flow, Space, and Activity Relationship FLOW, SPACE, AND ACTIVITY RELATIONSHIP DEPARTMENTAL PLANNING 11/03/2014. Data requirement for layout decisions

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FLOW, SPACE, AND ACTIVITY RELATIONSHIP

Mata Kuliah: Tata Letak Fasilitas (TKI 4215)

www.aeunike.lecture.ub.ac.id

Flow, Space, and Activity Relationship

• In determining the requirements of a facility, three important considerations are:

–Flow

•Depends on lot sizes, unit load sizes, material handling equipment and strategies, layout arrangement, and building configuration –Space

•Is a function of lot sizes, storage system, production equipment type and size, layout arrangement, building configuration, housekeeping and organization policies, material handling equipment, and office, cafetaria, and resttoom design –Activity relatioships

•Are defined by material or personal flow, environmental considerations, organizational structure, continous improvement methodology (teamwork activities), control issues, and process requirements

Data requirement for layout decisions

• Frequency of flow of material / some other measure of interaction between

departments

• Shape and size of departments

• Floor space available

• Location restrictions for departments, if any

• Adjacency requirements between pairs of departments, if any

DEPARTMENTAL PLANNING

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Types of Departments/Layouts

Volume High

Medium

Low

Low Medium High Variety Product

Department

Fixed Materials Location Department

Process Department Product

Family Department Product

Layout

Fixed Location Layout

Group Technology Layout

Process Layout

Source: John S. Usher class notes

Five types of layout

• Product layout

• Process layout

• Fixed-position layout

• Group-technology layout

• Hybrid layout

Product layout

Product Layouts

L L

L M

M

M D

D

D G

G

G A

A

Product C Department Product A Department

P P

P Product B Department

A

Shipping Department

Receiving Department

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Process layout

TM

TM TM

TM

DM

DM DM

VMM VMM BM BM

The Process Layout

L L L L L

L L L L

L M

M M

M D

D D

D

G

G G

G

A A A

Receiving and

Shipping Assembly

Painting Department Lathe Department Milling

Department Drilling Department

Grinding Department

P

Flow of Materials in Process Layouts

L L L L L

L L L L

L M

M M

M D

D D

D

G

G G

G

A A A

Receiving and

Shipping Assembly

Painting Department Lathe Department Milling

Department Drilling Department

Grinding Department

P

Source: Russell & Taylor, 2007

Group technology layout

TM

TM TM DM

DM

VMM

BM BM

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Product Family (Cellular) Layout

L L

L

L L

L M

M

M D D

D D

D

D G

G G G

G

G A A

Receiving and Shipping

Special Department Rotational

Parts Cell

P P

Rectangular Parts

Cell

A Manufacturing Cell

Key:

S = Saw L = Lathe

HM = Horizontal milling machine VM = Vertical milling machine G = Grinder

Paths of three workers moving within cell Material movement

In Out

Worker 1 Worker 2

Worker 3

Direction of part movement within cell

S L

HM

VM

G VM L

Final inspection

Finished part

Project (Fixed-Position) Layout

L

L L L

M

D D D

G G G

G

A A

Receiving and Shipping P

Storage

Hybrid layout

TM

TM TM

TM

DM

VMM BM

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Hybrid Layouts

• Combination of the layouts discussed.

• A combination of group layout in manufacturing cells, product layout in assembly area, and process layout in the general machining and finishing section is used.

TM

TM TM

DM

BM

General Characteristics

Characteristic Product Process Product

Family Project

Throughput Time Low High Low Medium

Work in process Low High Low Medium

Skill Level Choice High Med-High Mixed

Product Flexibility Low High Med-High High

Demand Flexibility Medium High Medium Medium

Mach Utilization High Med-Low Medium-High Medium

Worker Utilization High High High Medium

Reliability Can be low

High High Medium

Unit production cost

Low High Low High

Exercise – What Type of Layout?

• Ford Louisville Assembly Plant ___________

• Suburban Hospital ___________

• Louisville International Airport ___________

• KFC Restaurant ___________

• Boeing Aircraft ___________

Automated Manufacturing Cell

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Flexible Manufacturing Systems

Automated machining operations, tool changers

Automated material handling, computer control

Designed around size of parts processed & average processing time for parts

Can process wide variety of items quickly

Very few large systems exist

• Progressive layout – all parts same route

• Closed loop – larger variety, alternative routes

• Ladder layout – two machines work on same part

• Open field layout – most complex

Flow diagram

MESIN FRAIS MESIN BUBUT

MESIN BOR MESIN BOR

MEJA

PENERIMAANPENYIMPANANALAT

MEJAPERAKITAN Peluncur

Bahan

Peluncur Bahan

PEMANGGANG

PAINTING PENGEMASAN

Peluncur Bahan

Peluncur

Bahan 1

1

2

2 1

3

MEJA

3

2 5

4

6

3 6

5

7

6 8

4

9

5

11 712 8

13 6

149

15 7

1016 17

11

18

8 18

12

2013 PENGIRIMAN FINISHING ASSEMBLING

GUDANG

DIAGRAM ALIR (FLOW DIAGRAM)

FLOW PATTERN

Flow pattern at 800-acre Nissan plant in Smyrna, TN (1989)

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Flow Within Departments:

(a). End-to-end; (b). Back-to-back; (c). Front-to-front;

(d). Circular; (e). Odd angle

Flow Between Departments:

Straight Line atau pola aliran lurus ( I Flow)

• Proses yang berlangsung singkat

• Proses produksinya relatif sederhana

• Item tunggal/sedikit, jumlah produksi yang besar.

• Pola aliran bahan ini akan memberikan : –Jarak perpindahan yang pendek antar proses.

–Proses berlangsung lurus sesuai urutan mesin

• Jarak perpindahan bahan total akan kecil

O-1 O-2 O-3 O-4 O-5

Serpentine atau zig-zag (S Flow)

(A) O-1

O-2 O-3

O-4 O-5

O-6

O-1 O-2

O-4 O-3

O-5 O-6

(B)

Pola aliran seperti huruf “S” diatas sangat baik diterapkan bilamana aliran proses produksi lebih panjang dibandingkan dengan panjang area yang tersedia. Untuk itu aliran bahan dibelokkan untuk mengurangi panjangnya garis aliran yang ada.

Pola aliran menyerupai huruf “U”

(U Flow)

O-1 O-2 O-3

O-4 O-5

O-6

Pola aliran ini dipakai bilamana dikehendaki akhir dari proses produksi akan berada pada lokasi yang sama dengan awal proses produksi. Hal ini meningkatkan pemanfaatan fasilitas transportasi dan mudah untuk mengawasi keluar masuknya material dan produk jadi. Aliran perpindahan bahan relatif panjang .

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O-1 O-2

O-3 O-4

O-5 O-6

Pola aliran circular ini sangat baik diterapkan pada proses yang mengkehendaki pengembalian material atau produk jadi pada titik awal produksi. Pola ini juga dapat diterapkan pada proses yang menempatkan proses penerimaan bahan/material dan pengiriman barang jadi pada area yang sama.

Circular (O Flow)

O-1 O-2

O-3

O-4

O-5 O-6

• Tujuannya adalah untuk memperoleh garis aliran produk melewati suatu kelompok kerja dari area yang saling berkaitan.

• Proses perpindahan bahan (Material handling) secara mekanik.

• Terbatasnya ruang dan dikehendaki adanya pola aliran yang tetap

ODD angle

AT THE SAME LOCATION

ON ADJACENT SLIDES

AT THE SAME LOCATION

ON ADJACENT SLIDES

POLA ALIRAN MENURUT KELUAR-MASUK BAHAN

ON THE SAME SIDE BUT AT OPPOSITE ENDS ON THE SAME SIDE BUT AT OPPOSITE ENDS

ON OPPOSITE SIDES ON OPPOSITE SIDES

POLA ALIRAN MENURUT KELUAR-MASUK BAHAN

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A B E

D C

H

F G

UNINTERRUPTED FLOW PATHS

A F

E

H C

G

B D

INTERRUPTED FLOW PATHS

MACAM POLA ALIRAN YANG BERSILANGAN

POLA ALIRAN BAHAN UNTUK PROSES PERAKITAN (ASSEMBLY)

Pada pola aliran ini main assembly line akan disupplai dari sejumlah sub-assembly atau part line. Sub-assembly berada pada sisi yang sama.

Pola aliran bahan untuk proses perakitan:

Combination Assembly Line Patern

Tree Assembly Line / Spine Flow Patern

Sub-assembly line akan berada pada kedua sisi dari aliran main assembly. Biasanya pada penerapan pola aliran ini, main assembly akan berada ditengah bagian pabrik.

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Pola ini akan lebih tidak teratur dibanding dengan pola aliran sebelumnya.

Pada pola aliran ini, setiap bagian berlangsung operasi sepanjang lintasan produksi, menuju proses produksi yang lengkap untuk proses assembling.

Dendretic Assembly Line Patern

Overhead Assembly Line Patern

2nd Floor

1st Floor

Pola aliran ini merupakan model pola aliran untuk lantai produksi yang lebih dari satu lantai.

FLOW PLANNING

Flow planning hierarchy

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Flow Measurement

String Diagram merupakan alat untuk menggambarkan aliran bahan/material dalam layout, dengan menggunakan tali, benang, kawat, dan sebagainya.

A. STRING DIAGRAM

OTahapan pembuatan :

•Tusukkan paku, baut atau jarum pentul pada fasilitas- fasilitas dalam layout (pada titik proses dimulai atau berhenti)

•Hubungkan paku atau jarum yang telah dipasang sesuai dengan keterkaitan proses atau alur proses.

•Gunakan penghubung antar paku/titik menggunakan benang, karet, tali yang berwarna-warni

1

3

2

7

W/H FINISH GOOD

5 6

W/H MATERIAL 8 9 10 11 12

13

4 PENGOLAHAN

LIMBAH

Kemungkinan terjadinya kemacetan aliran

B. FROM TO CHART

ODikenal juga sebagai Travel Chart OSuatu teknik konvensional yang umum

digunakan untuk perencanaan tata letak pabrik dan pemindahan bahan dalam suatu proses produksi.

OSangat berguna dalam menganalisa aliran bahan pada proses dengan banyak item yang mengalir melalui suatu area.

OTeknik ini akan menunjukkan total berat beban yang harus dipindahkan, jarak perpindahan dan volume perpindahan

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LANGKAH PENYELESAIAN

PRODUK VOLUME OF HANDLING

% VOLUME OF

HANDLING ALUR PROSES

P1 2000 Kg 20 A-B-C-D-E-F-G-H-I

P2 2000 Kg 20 A-C-D-F-G-I

P3 2500 Kg 25 A-D-B-E-H-F-I

P4 2000 Kg 20 A-C-D-B-E-G-I

P5 500 Kg 5 A-E-F-G-H-I

P6 500 Kg 5 A-D-C-B-F-G-H_I

P7 500 Kg 5 A-C-D-H-D-G-I

OKumpulkan data “Volume of Handling”, luas area/departemen & alur proses produksi tiap produk

DIMENSI DEPARTEMEN

DEPARTEMEN DIMENSI (meter )

A 10 x 10

B 5 x 5

C 8 x 10

D 10 x 5

E 25 x 10

F 5 x 5

G 5 x 10

H 8 x 8

I 16 x 16

O Buatlah from to chart berdasarkan % volume handling (jarak untuk sementara dianggap sama)

FROM

A B C D E F G H I

TO

A

B 20 5 25+2

0

C ²⁰⁺²⁰⁺5 20 5

D 25+5 20+20+20+5 5

E 5 25+20 20

F 5 20

20+

5 25

G 5 20 20+20+5+5

H 5 25 20+5+5

I 25 20+20+5 20+5+

5

Perpindahan P1 dari A ke B Sebesar 20

FROM

A B C D E F G H J

TO

A 0

B 20 5 45 70

C 45 20 5 70

D 30 65 5 100

E 5 45 20 70

F 5 20 25 25 75

G 5 20 50 75

H 5 25 30 60

J 25 45 30 100

100 70 70 100 70 75 75 60 0 620

KONDISI AWAL

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Volume Aliran Dari Jarak Diagonal

FORWARD

Koefisien Jarak

BACKWARD Jarak dari

diagonal Moment Moment

Jarak dari diagonal (20+20+65+20+25+50+30+

30)

= 260 (260 x 1)

= 260 1

(10 x 1)

=10 ⁽⁵⁺⁵⁾

=10 (45+20+20+45)

=130 (130 x 2)

= 260 2

(70 x 2)

=140 (45+25)

=70 (30+45+5+25+25)

=130

(130 x 3)

= 390 3 0 0

(5+5+5)

=15 ^{(15 x 4)}= 60 4

(5 x 4)

=20 5

0 0 5 0 0

0 0 6 0 0

970 1140 170

85% 15%

BACK TRACKING

•Pada From to Chart diketahui adanya Back Tracking sebesar 15% dari total aliran bahan (ditandai dengan warna merah).

•Semakin kecil back tracking akan semakin baik

•Sehingga diperlukan evaluasi aliran proses yang mengalami back tracking, dalam kasus diatas adalah pada produk P3 dengan aliran awal A-D- B-E-H-F-I

•Kemudian dilakukan perubahan terhadap aliran P3 menjadi A-B-D-E-F-H-I

•Besarnya perubahan terhadap aliran P3 dapat dilihat pada tahap berikut ini.

FROM

A B C D E F G H I

TO

A

B 20+25 5 20

C ²⁰⁺²⁰⁺5 20 5

D 5 25 20+20+20

+5 5

E 5 20 20+2

5

F 5 20

20+5+2

5

G 5 20

20+20+5+

5

H 5 25 20+5+5

I 20+20+

5 20+5+5+2

5

Kondisi setelah perubahan aliran A-B-D-E-F-H-I

FROM

A B C D E F G H I

TO

A

B 45 5 20

C 45 20 5

D 5 25 65 5

E 5 20 45

F 5 20 50

G 5 20 50

H 5 25 30

I 45 55

KONDISI PERBAIKAN

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Volume Aliran Dari Jarak Diagonal

FRWD

Koefisien Jarak

BCWD Jarak dari

diagonal Moment

Jarak dari diagonal Moment

360 360 1 10 10

180 360 2 40 20

30 90 3 0 0

15 60 4 20 5

0 0 5 0 0

0 0 6 0 0

0 0 7 0 0

0 0 8 0 0

870 940 70

93% 7%

C. ACTIVITY

RELATIONSHIP CHART

O Prosedur pembuatan Activity Relationship Chart (ARC) sebagai berikut :

1. Identifikasi semua fasilitas kerja / departemen / mesin 2. Definisikan kriteria hubungan antar fasilitas kerja 3. Tentukan nilai hubungan antar fasilitas 4. Plot hasil perumusan nilai hubungan dalam ARC

Teknik kualitatif yang sederhana dalam merencanakan tata letak fasilitas atau mesin. Berdasarkan derajat hubungan aktivitas dari masing-masing fasilitas atau

mesin tersebut.

Kode Derajat Hubungan Antar Fasilitas

Value A E I O U X

Closeness Line code

Numerical weights

Absolutely necessary Especially important

Important Ordinary closeness OK

Unimportant Undesirable

16 8 4 2 0 80

OPercentages of A, E, I, O, U and X ratings

O A 2-5%

O E 3-10%

O I 5-15%

O O 10-25%

O U 25-60%

O X depends OColor coding relationships

O A Red

O E Orange or Yellow O I Green O O Blue O U Uncolored O X Brown

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I X

O

FASILITAS A FASILITAS B FASILITAS C 1

2 3

1 3 2

Derajat hubungan Alasan kedekatan

hubungan

ACTIVITY RELATION CHART

Contoh Alasan Kedekatan Hubungan

KODE

ALASAN DESKRIPSI ALASAN KEDEKATAN 1 Penggunaan data hasil proses secara besamaan 2 Penggunaan man power sharing 3 Penggunaan space area sharing 4 Tingginya tingkat hubungan personil 5 Keterkaitan pemakaian worksheet 6 Keterkaitan urutan proses kerja 7 Kesamaan proses kerja

8 Penggunaan jig and tools secara bersama 9 Ketidaknyamanan ketika berdekatan

A I E E U O O U I U O O A A E U O E U E X A O A O E O I E I A I E O I A U A I U O U U O U X O O U E X A U A U I

U

O O U U U U E UI

CNC Machine (10 x 25) Punch Press 2 (15 x 15) Vertical Turret Lathe (10 x 10) Lathe (10 x 15) Drill 1(10 x 10) Mill (20 x 20) Punch Press (15 x 15) Centerless Grinder (15 x 15) Shaper (10 x 20) Planer (10 x 20) Drill 2(10 x 10) Mill 2(15 x 20) 10 11 12 1 2 3 4 5 6 7 8 9

3 4

2

1 3

7 1

5 4

2 7

4 6 5

8 1

2 4

6 2

1

1 5

3 1 4 9

2

2 3 4 4

8 2 7

7

2 2

4 3

5

7 4

6 8

9 6 3 9

1 7 3

6

5 2 9

5 1 5 3 3 5

5

5 7

ACTIVITY RELATIONSHIP CHART

SPACE REQUIREMENT

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Space Requirements

• The most difficult determination in facilities planning

• The design year: 5-10 years

• Uncertainty –due to impact of technology, Changing product mix, changing demand levels, changing organization designs for the future

• Needs a systematic approach: “From the ground up”

• In manufacturing and office environments, space requirements should be determined first for individual workstations; next, departments, etc.

• Modern manufacturing approaches can reduce space requirements.

–Products are delivered to the points of use in smaller lot and unit load size

–Decentralised storage areas

–Less inventories (using a pulled system) –Manufacturing cells

–Companies are downsizing

Space Requirements

• Workstation Specification (space for equipment, materials, and personnel)

• Equipment Space consists of space for

–the equipment; machine travel;machine maintenance;

–plant services

• Materials Space consists of space for

–Receiving and storing materials; In-process materials;

–Storing and shipping materials; Storing and shipping waste and scrap; Tools, fixtures, jig, dies, and maintenance materials

• Personnel area consists of space for

–The operator; Material handling; Operator ingress and egress.

Space Requirements

• Department Specification

• Aisle Arrangement

• Visual Management and Space Requirement

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Space Requirements

Simple rules of thumb are used to determine the extra space that is required (Heragu, 1997)

 3 – 4 feet are added to the length and width of each machine or workstation

 The additional space is calculated as a percentage of the actual area occupied by a workstation, typically 200% to 300%

 Calculate the space required for the workstation, auxiliary equipment, operator space, incoming material and work in process space, and other additional space (e.g., load and unload acces, material handling carrier clearance) and add the separate quantities to determine the total space required (the preffered method of determining extra space)

Space Requirements

Workstation

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Aisle Allowance

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Departmental Service

Aisle Widths

Visual Management Visual Management

• Keterangan gambar:

A. Identification, housekeeping, and organization 1. Identification of the department 2. Identification of activities, resources, and products 3. Identification of the team

4. Markings on the floor 5. Markings of tools, racks, fixtures 6. Technical area 7. Communication and rest area 8. Information and instructions 9. Housekeeping tools B. Visual documentation

10. Manufacturing instructions and technical procedures area C. Visual production, maintenance, inventory, and quality control

11. Computer terminal 12. Production schedule 13. Maintenance schedule

14. Identification of inventories and work-in process 15. Monitoring signals for machines 16. Statistical process control 17. Record of problems D. Performance measurement