Mba Facility Layout u Basic layouts u Some layout techniques u Assembly line balancing u Service Layout

Mba Inputs to the Layout Decision 1. Specification of objectives of the system in terms of output and flexibility. 2. Estimation of product or service demand on the system. 3. Processing requirements in terms of number of operations and amount of flow between departments and work centers. 4. Space requirements for the elements in the layout. 5. Space availability within the facility itself.

Mba Basic Production Layouts u Process Layout u Product Layout u Group Technology (Cellular) Layout u Fixed-Position Layout

Mba Process Layout (also called job shop or functional layout) u What factors might we consider when determining the locations of process areas, or departments?

Mba Process Layout: Interdepartmental Flow u Given – The flow (number of moves) to and from all departments – The cost of moving from one department to another – The existing or planned physical layout of the plant u Determine – The “best” locations for each department, where best means interdepartmental transportation, or flow, costs

Mba Process Layout: Cut-And-Try Approach - see pp u Involves searching for departmental changes to reduce overall flow cost u Difficult to determine correct moves u Non-optimal and based on limited criteria (cost, flow and distance)

Mba Process Layout: CRAFT Approach (computerized method) u It is a heuristic program; it uses a simple rule of thumb in making evaluations: – "Compare two departments at a time and exchange them if it reduces the total cost of the layout." u It does not guarantee an optimal solution. u CRAFT assumes the existence of variable path material handling equipment such as forklift trucks.

Mba Process Layout: Systematic Layout Planning u Useful when numerical flow of items between departments – Can be impractical to obtain – Does not account for the qualitative factors that may be crucial to the placement decision u Systematic Layout Planning – Accounts for the importance of having each department located next to every other department – Is also guided by trial and error » Switching departments then checking the results of the “closeness” score

Mba Systematic Layout Planning-- Example Reasons for Closeness Code Reason Type of customer Ease of supervision Common personnel Contact necessary Share same price Psychology

Mba Systematic Layout Planning-- Example Importance of Closeness Value A E I O U X Closeness Line code Numerical weights Absolutely necessary Especially important Important Ordinary closeness OK Unimportant Undesirable

Mba Systematic Layout Planning-- Example Relating Reasons and Importance From 1. Credit department 2. Toy department 3. Wine department 4. Camera department 5. Candy department 6 I -- U 4 A U U 1 I 1,6 A -- U 1 X 1 X To Area (sq. ft.) Letter Number Closeness rating Reason for rating

Mba Systematic Layout Planning-- Example Initial Relationship Diagram U U E A I

Mba Systematic Layout Planning-- Example Initial and Final Layouts Initial Layout Ignoring space and building constraints ft 20 ft Final Layout Adjusted by square footage and building size

Mba Station 1 Mins per Unit 6 Station 2 7 Station 3 3 Assembly Lines (Product Layout) What’s Going to Happen?

Mba Example--Line Balancing u You’ve just been assigned the job a setting up an electric fan assembly line with the following tasks:

Mba Precedence Diagram A C B DEF G H u Which process step defines the maximum rate of production?

Mba The bottleneck

Mba We want to assembly 100 fans per day What does this figure represent?

Why should we always round up? 20 © The McGraw-Hill Companies, Inc., 1998 Irwin/McGraw-Hill

Mba Some Rules We’ll Follow for Loading Workstations u Primary: Assign tasks in order of the largest number of following tasks. u Secondary (tie-breaking): Assign tasks in order of the longest operating time

A C B DEF G H Precedence Diagram 22 © The McGraw-Hill Companies, Inc., 1998 Irwin/McGraw-Hill

A C B DEF G H Station 1Station 2 Station 3 TaskFollowersTime (Mins) A62 C43.25 D31.2 B2 1 E20.5 F11 G11 H © The McGraw-Hill Companies, Inc., 1998 Irwin/McGraw-Hill

A C B DEF G H Station 1Station 2 Station 3 A (4.2-2=2.2) TaskFollowersTime (Mins) A62 C43.25 D31.2 B2 1 E20.5 F11 G11 H © The McGraw-Hill Companies, Inc., 1998 Irwin/McGraw-Hill

A C B DEF G H A (4.2-2=2.2) B (2.2-1=1.2) TaskFollowersTime (Mins) A62 C43.25 D31.2 B2 1 E20.5 F11 G11 H01.4 Station 1Station 2 Station 3 25 © The McGraw-Hill Companies, Inc., 1998 Irwin/McGraw-Hill

A C B DEF G H A (4.2-2=2.2) B (2.2-1=1.2) G (1.2-1=.2) Idle=.2 TaskFollowersTime (Mins) A62 C43.25 D31.2 B2 1 E20.5 F11 G11 H01.4 Station 1Station 2 Station 3 26

A C B DEF G H C ( )=.95 TaskFollowersTime (Mins) A62 C43.25 D31.2 B2 1 E20.5 F11 G11 H01.4 A (4.2-2=2.2) B (2.2-1=1.2) G (1.2-1=.2) Idle=.2 Station 1Station 2 Station 3 27

A C B DEF G H C ( )=.95 Idle =.95 TaskFollowersTime (Mins) A62 C43.25 D31.2 B2 1 E20.5 F11 G11 H01.4 A (4.2-2=2.2) B (2.2-1=1.2) G (1.2-1=.2) Idle=.2 Station 1Station 2 Station 3 28

A C B DEF G H C ( )=.95 Idle =.95 D ( )=3 TaskFollowersTime (Mins) A62 C43.25 D31.2 B2 1 E20.5 F11 G11 H01.4 A (4.2-2=2.2) B (2.2-1=1.2) G (1.2-1=.2) Idle=.2 Station 1Station 2 Station 3 29 © The McGraw-Hill Companies, Inc., 1998 Irwin/McGraw-Hill

A C B DEF G H C ( )=.95 Idle =.95 D ( )=3 E (3-.5)=2.5 TaskFollowersTime (Mins) A62 C43.25 D31.2 B2 1 E20.5 F11 G11 H01.4 A (4.2-2=2.2) B (2.2-1=1.2) G (1.2-1=.2) Idle=.2 Station 1Station 2 Station 3 30 © The McGraw-Hill Companies, Inc., 1998 Irwin/McGraw-Hill

A C B DEF G H C ( )=.95 Idle =.95 D ( )=3 E (3-.5)=2.5 F (2.5-1)=1.5 TaskFollowersTime (Mins) A62 C43.25 D31.2 B2 1 E20.5 F11 G11 H01.4 A (4.2-2=2.2) B (2.2-1=1.2) G (1.2-1=.2) Idle=.2 Station 1Station 2 Station 3 31 © The McGraw-Hill Companies, Inc., 1998 Irwin/McGraw-Hill

A C B DEF G H C ( )=.95 Idle =.95 D ( )=3 E (3-.5)=2.5 F (2.5-1)=1.5 H ( )=.1 Idle =.1 Which station is the bottleneck? What is the effective cycle time? TaskFollowersTime (Mins) A62 C43.25 D31.2 B2 1 E20.5 F11 G11 H01.4 A (4.2-2=2.2) B (2.2-1=1.2) G (1.2-1=.2) Idle=.2 Station 1Station 2 Station 3 32 © The McGraw-Hill Companies, Inc., 1998 Irwin/McGraw-Hill

Mba Efficiency of the Assembly Line

Mba Group Technology Benefits 1. Better human relations 2. Improved operator expertise 3. Less in-process inventory and material handling 4. Faster production setup

Mba Group Technology Transition from Process Layout 1. Grouping parts into families that follow a common sequence of steps. 2. Identifying dominant flow patterns of parts families as a basis for location or relocation of processes. 3. Physically grouping machines and processes into cells.

Mba Fixed Position Layout u What are our primary considerations for a fixed position layout?

Mba Retail Service Layout u Goal--maximize net profit per square foot of floor space u What about the humanistic considerations? – The “servicescape”

Mba Servicescapes u Ambient Conditions u Spatial Layout and Functionality u Signs, Symbols, and Artifacts