Presentation is loading. Please wait.

Presentation is loading. Please wait.

9-1 Operations Management Layout Strategy Chapter 9.

Similar presentations


Presentation on theme: "9-1 Operations Management Layout Strategy Chapter 9."— Presentation transcript:

1 9-1 Operations Management Layout Strategy Chapter 9

2 9-2 Outline  Strategic Importance of Layout Decisions.  Fixed-Position Layout.  Office Layout.  Process-Oriented Layout (Flow graphs).  Retail Layout.  Warehouse Layout.  Product-Oriented Layout (Assembly line balancing).

3 9-3 What is Facility Layout  Location or arrangement of everything within & around buildings.  Objectives are to maximize:  Utilization of space, equipment, & people.  Efficient flow of information, material, & people.  Employee morale & safety.  Trend is towards flexible and dynamic layouts.

4 9-4 Facility Layout  Helps achieve competitive advantage:  Better, faster, cheaper.  Determines productivity, cost, quality, flexibility, image, etc.  May involve a blend of strategies.

5 9-5 Six Layout Strategies  1. Fixed-position layout.  For large unique projects such as ships and buildings.  2. Office layout.  Positions workers, equipment, and spaces/offices to provide for movement of information and material.  3. Process-oriented layout.  For low-volume, high-variety production.

6 9-6 Six Layout Strategies - continued  4. Retail/service layout.  Arranges facility and allocates shelf space in light of customer behavior.  5. Warehouse layout.  Addresses trade-offs between space utilization and material handling.  6. Product-oriented layout.  For repetitive or continuous production.

7 9-7 Layout Strategies Project (fixed-position) Job Shop (Process-oriented) Office Examples Problem Ingal Ship Building Pittsburgh Airport Shouldice Hospital Olive Garden Allstate Insurance Microsoft Move material to limited storage areas at the site. Manage varied material flow for each product. Locate workers requiring contact close to each other.

8 9-8 Layout Strategies Retail Warehouse (storage) Repetitive /Continuous (Product-oriented) Examples Problem Kroger’s Supermarket Famous-Barr Federal-Mogul’s Warehouse The Gap’s distribution center Sony’s TV Assembly Line Dodge Caravans Expose customer to high-margin items. Balance cost for storage and material handling. Equalize the task time at each workstation.

9 9-9 Requirements for a Good Layout  Understand capacity and space requirements.  Understand information flows.  Understand cost of people and product flows.  Select appropriate material handling equipment.  Consider environment and aesthetics.  Consider safety and regulations.

10 9-10 Constraints on Layout Objectives  Product/service design.  Volume of business.  Process equipment & capacity.  Quality of work life.  Building and site.

11 9-11 1. Fixed-Position Layout  Project is stationary.  Special purpose: Construction, shipbuilding, etc.  Workers and equipment come to site.  Complicating factors.  Limited space at site.  Changing material needs.  Unique projects.

12 9-12 2. Office Layout  Positions people, equipment, & offices.  Usually for maximum information flow.  Also can consider material flow.  Arranged by process or product.  Example: Payroll dept. is by process.  Different cultures have different expectations for space.  Relationship (or proximity) chart used.

13 9-13 Relationship (Proximity) Chart  Uses 6 levels to express desired proximity. A = Absolutely necessary E = Especially important I = Important O= Ordinary importance U = Unimportant X = Not desirable

14 9-14 Relationship (Proximity) Chart 1 President O 2 CostingU EA 3 EngineeringI U 4 President’s Secretary 5 Photocopiers U E A X

15 9-15 Relationship (Proximity) Chart 1 President O 2 CostingU EA 3 EngineeringI U 4 President’s Secretary 5 Photocopiers U E A X 1 4 3 2 5 A A E E I X Can determine layout using proximity diagram

16 9-16 Office Layout 1 President O 2 CostingU EA 3 EngineeringI U 4 President’s Secretary 5 Photocopiers U E A X 1 4 3 2 5 A A E E I X Locate 5 offices in a rectangular space. Offices 2-5 are to be same size. Office 1 (President’s) is twice as large.

17 9-17 Office Layout Costing (3) Photocopiers (5) President’s Secretary (4) (2) President (1) Engineering Corridor

18 9-18 3. Process-Oriented Layout  Place departments with large flows of material or people close together.  Similar processes and equipment are located in close proximity.  For example, all x-ray machines in same area.  Used with process-focused processes.  Low volume, high variety.

19 9-19 Emergency Room Layout Surgery Radiology E.R. bedsPharmacyBilling/exit E.R.Triage room E.R. Admissions Patient B - erratic pacemaker Patient A - broken leg Hallway

20 9-20 Process-Oriented Layout Advantages  Flexibility.  Allows wide variety of products.  Low fixed costs for general purpose equipment.  Breakdown of one machine or worker does not stop processing.

21 9-21 Process-Oriented Layout Disadvantages  Scheduling is difficult.  High variable cost.  High work-in-process inventory and waiting.  High labor skills required.

22 9-22 Developing a Process-Oriented Layout by Hand Goal: Minimize cost of moving between departments. 1 Construct a “from-to matrix”. 2 Determine space requirements for each department. 3 Develop an initial layout and try to place departments with large flows close together. 4 Determine the cost of this initial layout. 5 Improve the initial layout (by hand or more sophisticated means). 6 Consider factors in addition to transportation cost.

23 9-23 Cost of Process-Oriented Layout

24 9-24 123456 1 2 3 4 5 6 4010000 0 10 40 10 0 0 0 80 50 0 0 10 0 0 0 20 10 0 0 20 0 0 0 0 Flows of Parts (loads/week) from to

25 9-25 Interdepartmental Flow of Parts 123456 1 2 3 4 5 6 501000020 30 50 10 0 200 100 50 0 0 Number of loads/week between departments

26 9-26 Initial Layout Room 1Room 2Room 3 Room 4Room 5Room 6

27 9-27 Initial Layout Flow Graph Showing Loads/Week 100 5030 10 20 50 20 100 50 1 2 4 5 6 3

28 9-28 Cost of Initial Layout 100 5030 10 20 50 20 100 50 1 2 4 5 6 3 1-2 50 = 50*1 1-3 200 = 100*2 1-6 40 = 20*2 2-3 30 = 30*1 2-4 50 = 50*1 2-5 10 = 10*1 3-4 40 = 20*2 3-6 100 = 100*1 4-5 50 = 50*1 Total = $570 Cost per load for adjacent locations = $1 Cost per load for non-adjacent locations = $2

29 9-29 Large Flows in Initial Layout 100 5030 10 20 50 20 100 50 1 2 4 5 6 3 Largest Flows:100 for 1-3 & 3-6, so put 3 close to 1 and 6. 50 for 1-2, 2-4 & 4-5,

30 9-30 Improved Layout Flow Graph 100 50 30 10 20 50 20 50 2 4 31 56

31 9-31 Improved Layout Printing Department (2) Assembly Department (1) Machine shop Department (3) Receiving Department (4) Shipping Department (5) Testing Department (6) Room 1Room 2Room 3 Room 4Room 5Room 6

32 9-32 Cost of Improved Layout 1-2 50 = 50*1 1-3 100 = 100*1 1-6 20 = 20*1 2-3 60 = 30*2 2-4 50 = 50*1 2-5 10 = 10*1 3-4 40 = 20*2 3-6 100 = 100*1 4-5 50 = 50*1 Total = $480 Cost per load for adjacent locations = $1 Cost per load for non-adjacent locations = $2 10050 30 10 20 50 20 50 2 4 31 56 100

33 9-33 Alternative Improved Layout 50 100 20 50 30 50 1 2 63 45 10

34 9-34 Cost of Alternative Improved Layout 1-2 50 = 50*1 1-3 100 = 100*1 1-6 40 = 20*2 2-3 30 = 30*1 2-4 50 = 50*1 2-5 20 = 10*2 3-4 20 = 20*1 3-6 100 = 100*1 4-5 50 = 50*1 Total = $460 Cost per load for adjacent locations = $1 Cost per load for non-adjacent locations = $2 50 100 20 50 30 50 1 2 63 45 10 Is this best?

35 9-35 Alternative Improved Layout Printing Department (2) Assembly Department (1) Machine shop Department (3) Receiving Department (4) Shipping Department (5) Testing Department (6) Room 1Room 2Room 3 Room 4Room 5Room 6

36 9-36 Layout Example 2 Given the following tables of interdepartmental flows and distances between locations A-E, locate the five departments to minimize the total distancexflow. Interdepartmental flows 1 2 3 4 5 1 - 13 18 3 0 2 - 15 0 6 3 - 0 4 4 - 4 A B C D E A - 9 8 12 14 B 9 - 9 6 7 C 8 9 - 4 9 D 12 6 4 - 14 Distances between locations E 14 7 9 14 -

37 9-37 Layout Example 2 Largest flow 1-3 (flow=18) should be in closest locations: C&D Could have: Solution 1: C=1 and D=3 or Solution 2: C=3 and D=1 Interdepartmental flows 1 2 3 4 5 1 - 13 18 3 0 2 - 15 0 6 3 - 0 4 4 - 4 A B C D E A - 9 8 12 14 B 9 - 9 6 7 C 8 9 - 4 9 D 12 6 4 - 14 Distances between locations E 14 7 9 14 -

38 9-38 Layout Example 2 Next largest flow is 2-3, so 2 should be placed in location closest to 3. Solution 1: D=3 and closest open location to D is B, so B=2, C=1, D=3. Solution 2: C=3 and closest open location to C is A, so A=2, C=3, D=1. Interdepartmental flows 1 2 3 4 5 1 - 13 18 3 0 2 - 15 0 6 3 - 0 4 4 - 4 A B C D E A - 9 8 12 14 B 9 - 9 6 7 C 8 9 - 4 9 D 12 6 4 - 14 Distances between locations E 14 7 9 14 -

39 9-39 Layout Example 2 Next largest flow is 1-2, but 1 and 2 are already located. So consider next largest flow 2-5. Solution 1: B=2 and closest open location to B is E, so A=4,B=2,C=1, D=3,E=5. Solution 2: A=2 and closest open location to A is B, so A=2,B=5,C=3, D=1,E=4. Interdepartmental flows 1 2 3 4 5 1 - 13 18 3 0 2 - 15 0 6 3 - 0 4 4 - 4 A B C D E A - 9 8 12 14 B 9 - 9 6 7 C 8 9 - 4 9 D 12 6 4 - 14 Distances between locations E 14 7 9 14 -

40 9-40 Layout Example 2 Solution 1: A=4,B=2,C=1, D=3,E=5. Distance = 13x9 + 18x4 + 3x8 + 15x6 + 6x7 + 4x14 + 4x14 = 457 Solution 2: A=2,B=5,C=3, D=1,E=4. Distance = 13x12 + 18x4 + 3x14 + 15x8 + 6x9 + 4x9 + 4x7 = 508 Interdepartmental flows 1 2 3 4 5 1 - 13 18 3 0 2 - 15 0 6 3 - 0 4 4 - 4 A B C D E A - 9 8 12 14 B 9 - 9 6 7 C 8 9 - 4 9 D 12 6 4 - 14 Distances between locations E 14 7 9 14 - Solution 1 is best!

41 9-41 Computer Programs for Layout  Many different programs:  CRAFT  SPACECRAFT  CRAFT 3-D  CORELAP  ALDEP  All are heuristic - not necessarily optimal!!

42 9-42 Work Cells in Process Layouts  Special case of product-oriented layout - in a process-oriented facility.  Different machines brought together to make a product.  Use when high volume warrants special arrangement.  For 1 product or a small group of products.  Temporary arrangement.  Example: Assembly line set up to produce 3000 identical parts in a job shop.

43 9-43 Work Cell Floor Plan Office Tool Room Work Cell SawsDrills

44 9-44 Work Cell Advantages Lower: Inventory. Floor space. Direct labor costs. Higher: Equipment utilization. Employee participation. Quality.

45 9-45 Work Cells, Focused Work Centers and the Focused Factory Work Cell A temporary assembly-line-oriented arrangement of machines and personnel in what is ordinarily a process-oriented facility. Focused Work Center A permanent assembly-line-oriented arrangement of machines and personnel in what is ordinarily a process-oriented facility. Focused Factory A permanent facility to produce a product or component in a product-oriented facility.

46 9-46 4. Retail/Service Layout  Maximize product exposure to customers.  Maximize profitability per square foot of floor space or per linear foot of shelf space.  Decision variables:  Arrangement of store.  Store flow pattern.  Allocation of (shelf) space to products. Video

47 9-47 Retail Layouts - Rules of Thumb  Locate high-draw items around the periphery.  Use prominent locations (end aisle locations; first or last aisle) for high-impulse and high margin items.  Remove crossover aisles to prevent customers from moving between aisles.  Distribute “power items” (that dominate a shopping trip) around store to increase the viewing of other items.  Locate far apart.  Locate on both sides of an aisle.

48 9-48 Grocery Store Layout

49 9-49 Retail Store Shelf Space  Consider prominence of shelf location and number of facings.  Can use computerized tools to manage shelf-space.  Track sales and product location (scanner data). 5 facings PERT

50 9-50 Servicescape Considerations  Ambient conditions.  Background characteristics such as lighting, sound, smell, and temperature.  Spatial layout and functionality.  Customer circulation, aisle width, shelf spacing, etc.  Signs, Symbols, and Artifacts.  Various other characteristics of design (carpeting, greeters, etc.).

51 9-51 5. Warehouse Layout  Balance space utilization & handling cost.  Similar to process layout.  Items moved between loading docks & various storage areas.  Optimum layout depends on:  Variety of items stored.  Number of items picked.

52 9-52 Space Utilization vs. Handling Costs  High space utilization (for storage).  Small, narrow aisles.  Product stacked high and deep (not easily accessible).  Ease of material handling.  Wide, short aisles.  Product easily accessible.  Design facility to optimize space utilization and handling costs tradeoff.

53 9-53 Assigned vs. Random Stock Locations  Assigned locations for products:  May be inefficient use of space.  Easier order picking and re-stocking.  Random locations:  More efficient use of space.  Added costs to track location of inventory and “open” space.  More difficult order picking and re-stocking.  Stock products to optimize cost and efficiencies tradeoffs.

54 9-54 Cross Docking (Wal-Mart)  Transferring goods:  From incoming trucks at receiving docks.  To outgoing trucks at shipping docks.  Avoids placing goods into storage.  Requires suppliers provide effective addressing (bar codes) and packaging for rapid transshipment. In- coming Outgoing

55 9-55 Order Picking Collecting items on a customer order from various locations in the warehouse.  Sequence items to minimize travel time in warehouse to pick order.  Also, should locate items to be efficient to pick.  Combine several orders to reduce picking time.  Zoning : Assign separate pickers to different zones in the warehouse.  Split order among several pickers.

56 9-56 6. Product-Oriented Layout  Used with product-focussed processes.  Facility organized around product.  High volume, low variety.  Types:  Fabrication line - Builds components.  Assembly line - Assembles components into products.

57 9-57 Product-Oriented Layout  Divide work into small tasks. To be done by workers or machines.  Assign tasks to workstations.  Balance output of each workstation.  To smooth operations of the line.  To make workload equal.  To minimize idle time.  To achieve desired output.

58 9-58 Product-Oriented Requirements  Standardized product.  High production volume.  Stable production quantities.  Uniform quality of raw materials & components.

59 9-59 Product-Oriented Layout Advantages  Lower variable cost per unit.  Lower material handling costs.  Lower work-in-process inventories.  Rapid throughput.  Easier training & supervision.

60 9-60 Product-Oriented Layout Disadvantages  Higher capital investment for special equipment.  Any work stoppage stops whole process.  Lack of flexibility in volume and product.

61 9-61 Repetitive Layout Note: 5 tasks or operations (T1-T5); 3 work stations (orange rectangles)

62 9-62 Assembly Line Balancing Steps 1.Determine tasks (operations) & task times. 2.Determine sequence of tasks. 3.Draw precedence diagram. 4.Calculate cycle time. 5.Calculate minimum number of work stations, N. 6.Assign tasks. 7.Calculate efficiency.

63 9-63 Assembly Line Balancing Data Usually we are given:  Production rate.  Units of product to be produced per unit time.  Production time available per day.  Tasks (operations) & task times.  Sequence of tasks.

64 9-64 Assembly Line Balancing General Procedure 1. Determine cycle time - The time between production of successive units. (May be measured in seconds, minutes, etc.) 2. Calculate the theoretical minimum number of workstations, denoted N. (May not be achievable.) 3. Assign tasks to workstations to “balance” the line. Compute the efficiency.

65 9-65 Assembly Line Balancing Equations Cycle time = Production time available Production rate Minimum number of work stations  Task times Cycle time Efficiency = =  Task times * (Cycle time) (Actual number of work stations) = N Rounded up

66 9-66 Assembly Line Balancing Example TaskTime Predecessor A 0.1 min.- B 0.7 min.A C 1.0 min.B D 0.5 min.C E 0.2 min.D 2.5 min. Immediate AB C D E 0.1 0.2 0.71. 0 0.5 Suppose we want to produce 300 units/day and 8 hours are available each day.

67 9-67 Assembly Line Balancing Example TaskTime Predecessor A 0.1 min. - B 0.7 min. A C 1.0 min. B D 0.5 min. C E 0.2 min. D 2.5 min. Immediate Suppose we want to produce 300 units/day and 8 hours are available each day. So assign tasks A-E to 2 workstations, where neither workstation should exceed 1.6 minutes.

68 9-68 Assembly Line Balancing Example AB C D E 0.1 0.2 0.71. 0 0.5 Suppose we want to produce 300 units/day and 8 hours are available each day. Can not use only 2 workstations! Must use 3. Efficiency=2.5/(3*1.6) = 52.1% TaskTime Predecessor A 0.1 min. - B 0.7 min. A C 1.0 min. B D 0.5 min. C E 0.2 min. D 2.5 min. Immediate

69 9-69 Assembly Line Balancing Example AB C D E 0.1 0.2 0.71. 0 0.5 Both of these can produce 300/day in 8 hours. Efficiency=2.5/(3*1.6) = 52.1% AB C D E 0.1 0.2 0.71. 0 0.5 Efficiency=2.5/(3*1.6) = 52.1% Better balance! Note: this line could produce 300 units in 5 hours (1 per minute) Efficiency=2.5/(3*1.0) = 83.3%

70 9-70 Assembly Line Balancing Example AB C D E 0.1 0.2 0.71. 0 0.5 If 2 workstations were required, then it will take more than 8 hours to produce 300 units. Cycle time = 1.7 minutes Efficiency=2.5/(2*1.7) = 73.5% Time to produce 300 units 1.7 min/unit*300 units = 510 minutes = 8.5 hours

71 9-71 Assembly Line Balancing Heuristics  Longest (or shortest) task time.  Choose task with longest (or shortest) operation time.  Most following tasks.  Choose task with largest number of following tasks.  Ranked positional weight.  Choose task where the sum of the times for each following task is longest.  Least number of following tasks.  Choose task with fewest subsequent tasks.

72 9-72 Ranked Positional Weight Heuristic Positional weight = Sum of times for a task and all tasks that must follow it. 1. Calculate positional weight for each task. 2. Assign task with largest positional weight to the earliest workstation where it fits. - Obey precedence relations. - Do not exceed cycle time. 3. Repeat step 2 until all tasks are assigned.

73 9-73 Line Balancing Example 2 TaskTime Predecessor A 0.2 min.- B 0.6 min. A,C C 0.5 min.- D 0.3 min.- E 1.0 min. B,D F 0.2 min.D G 0.9 min. E,F 3.7 min. Immediate Suppose we want to produce 450 units/day and 8 hours are available each day.

74 9-74 Line Balancing Example 2 TaskTime Predecessor A 0.2 min. - B 0.6 min. A,C C 0.5 min. - D 0.3 min. - E 1.0 min. B,D F 0.2 min. D G 0.9 min. E,F 3.7 min. Immediate Suppose we want to produce 450 units/day and 8 hours are available each day.

75 9-75 A B E C D F G 0.2 Precedence Diagram - Example 2 0.5 0.3 0.6 0.2 1.0 0.9

76 9-76 Example 2 - Positional Weight TaskTime Predecessor weight A 0.2 min.- 2.7 B 0.6 min. A,C 2.5 C 0.5 min.- 3.0 D 0.3 min.- 2.4 E 1.0 min. B,D 1.9 F 0.2 min.D 1.1 G 0.9 min. E,F 0.9 3.7 min. Immediate Positional

77 9-77 Example 2 - Assign Tasks TaskTime Predecessor weight A 0.2 min. - 2.7 B 0.6 min. A,C 2.5 C 0.5 min. - 3.0 D 0.3 min. - 2.4 E 1.0 min. B,D 1.9 F 0.2 min. D 1.1 G 0.9 min. E,F 0.9 3.7 min. ImmediatePositional Cycle time = 1.07 min. N = 4 workstations WS1WS2WS3WS4 C (0.5) A (0.2)

78 9-78 Example 2 - Assign Tasks (cont.) TaskTime Predecessor weight A 0.2 min. - 2.7 B 0.6 min. A,C 2.5 C 0.5 min. - 3.0 D 0.3 min. - 2.4 E 1.0 min. B,D 1.9 F 0.2 min. D 1.1 G 0.9 min. E,F 0.9 3.7 min. ImmediatePositional Cycle time = 1.07 min. N = 4 workstations WS1WS2WS3WS4 C (0.5) B (0.6) A (0.2) D (0.3)

79 9-79 Example 2 - Assign Tasks (cont.) TaskTime Predecessor weight A 0.2 min. - 2.7 B 0.6 min. A,C 2.5 C 0.5 min. - 3.0 D 0.3 min. - 2.4 E 1.0 min. B,D 1.9 F 0.2 min. D 1.1 G 0.9 min. E,F 0.9 3.7 min. ImmediatePositional Cycle time = 1.07 min. N = 4 workstations WS1WS2WS3WS4 C (0.5) B (0.6) E (1.0) G (0.9) A (0.2) F (0.2) D (0.3) Efficiency = 3.7/(4*1.07) = 86.4%

80 9-80 A B E C D F G 0.2 Precedence Diagram - Example 2 0.5 0.3 0.6 0.2 1.0 0.9 WS1 WS2 WS3 WS4

81 9-81 Example 2 - Final Comment TaskTime Predecessor A 0.2 min. - B 0.6 min. A,C C 0.5 min. - D 0.3 min. - E 1.0 min. B,D F 0.2 min. D G 0.9 min. E,F 3.7 min. Immediate Could use a cycle time of 1 minute & produce 450 units in 7.5 hours WS1WS2WS3WS4 C (0.5) B (0.6) E (1.0) G (0.9) A (0.2) F (0.2) D (0.3) Efficiency = 3.7/(4*1.0) = 92.5%


Download ppt "9-1 Operations Management Layout Strategy Chapter 9."

Similar presentations


Ads by Google