1. Process Selection and Facility Layout

2. Process selection – Deciding on the way production of goods or services will be organized Major implications – Capacity planning – Layout of facilities – Equipment – Design of work systems Introduction

3. Forecasting Product and Service Design Technological Change Capacity Planning Process Selection Facilities and Equipment Layout Work Design Process Selection and System Design Inputs Outputs

4. Key aspects of process strategy – Capital intensive – equipment/labor – Process flexibility – Adjust to changes – Design – Volume – Technology Process Strategy

5. Variety – How much Flexibility – What degree Volume – Expected output Job Shop Batch Repetitive Continuous Process Selection

6. Process types

7. Job shop – Small scale, wide variety of goods Batch – Moderate volume, flexible Repetitive or assembly line – High volumes of standardized goods or services Continuous – Very high volumes of non-discrete goods Projects – Nonroutine work, uniqe set ob objectives, limited timeframe and resources Process types and volume

8. Product – Process Matrix The diagonal of the matrix represents the ideal choice of processing system for a given sets of circumstances.

9. Functions/activities affected by process choice Job variety, process flexibility, unit cost Volume Limited (not ongoing)

10. Product and service life cycles Alongside the life cycle the sales and with it the producion volume can change. So managers must be aware of the change in the optimal processing system. (the necessity of change is highly dependent on the particular good or service)

11. Product/Service Profilig Linking key product or service requirements to process capavilities. Design the process with taking into consideration the following: – Range of products/services – Expected order size – Pricing – Expected frequency of changes in schedules etc. – Order-winning requirements – …

12. Sustainable production Non-polluting Conserving natural resources & energy Economically efficient Safe and healthful for workers, communities and consumers Socially and creaqtively rewarding for workers

13. Automation: Machinery that has sensing and control devices that enables it to operate – Fixed automation – Programmable automation Automation of production and services

14. Advantages of automation Low variability in performance and quality Machines do not – get bored or distracted – go out on strike or ask for higher wages – lower variable costs

15. Disadvantages Higher initial (investment) cost and Higher fixed costs Lower felxibility Higher skills needed Lower morale of human workforce Need for standardisation – Products – Processes – Equipment and materials etc.

16. Computer-aided design and manufacturing systems (CAD/CAM) Numerically controlled (NC) machines Computerized numerical control (CNC) Direct numerical control (DNC) Robot: mechanical arm + power supply + controller Manufacturing cell Flexible manufacturing systems (FMS) Computer-integrated manufacturing (CIM) Automation

17. Layout: the configuration of departments, work centers, and equipment, with particular emphasis on movement of work (customers or materials) through the system Facilities Layout

18. Requires substantial investments of money and effort Involves long-term commitments Has significant impact on cost and efficiency of short-term operations Importance of Layout Decisions

19. The Need for Layout Decisions Inefficient operations High (variable) Cost Bottlenecks Changes in the design of products or services The introduction of new products or services Safety Changes in environmental or other legal requirements Changes in volume of output or mix of products Changes in methods and equipment Morale problems

20. Objectives of facility layout Main: smooth flow of work, material and information Supporting objectives:

21. Product layouts Process layouts Fixed-Position layout Hybrid types: Combination layouts Basic Layout Types

22. Product layout – Layout that uses standardized processing operations to achieve smooth, rapid, high-volume flow Process layout – Layout that can handle varied processing requirements Fixed Position layout – Layout in which the product or project remains stationary, and workers, materials, and equipment are moved as needed Basic Layout Types

23. Used for Repetitive or Continuous Processing Product Layout

24. High rate of output Low unit cost Labor specialization Low material handling cost High utilization of labor and equipment Established routing and scheduling Routing accounting and purchasing Advantages of Product Layout

25. Creates dull, repetitive jobs Poorly skilled workers may not maintain equipment or quality of output Fairly inflexible to changes in volume Highly susceptible to shutdowns Needs preventive maintenance Individual incentive plans are impractical Disadvantages of Product Layout

26. A U-Shaped Production Line

27. Advantages/disadvantages of U-shaped lines Shorter distances for workers & machines Permits communication thus facilitates teamwork More flexible work assignments Optimal is the facility has the same entry and exit point If lines are highly automated, there is no need for communication and travel If entry points are on the opposite side as exit points Noise and contamination factors are increased in the U-shape

28. Dept. A Dept. BDept. D Dept. C Dept. F Dept. E Used for Intermittent processing Job Shop or Batch Process Layout (functional) Process Layout

29. Work Station 1 Work Station 2 Work Station 3 Product Layout (sequential) Used for Repetitive Processing Repetitive or Continuous Product Layout

30. Can handle a variety of processing requirements Not particularly vulnerable to equipment failures Equipment used is less costly Possible to use individual incentive plans Advantages of Process Layouts

31. In-process inventory costs can be high Challenging routing and scheduling Equipment utilization rates are low Material handling slow and inefficient Complexities often reduce span of supervision Special attention for each product or customer Accounting and purchasing are more involved Disadvantages of Process Layouts

32. Fixed-position layouts The product or project remains stationary and workers, materials, and equipment are moved as needed. If weight, size, bulk, or some other factor makes it undesirable or extremely difficult to move the product. E.g. firefighting, road-building, home-building, drilling for oil etc.

33. Cellular Production – Layout in which machines are grouped into a cell that can process items that have similar processing requirements Group Technology – The grouping into part families of items with similar design or manufacturing characteristics – Makes cellular production much more effective Cellular Layouts

34. Traditional process layout Cellular layout

35. DimensionFunctionalCellular Number of moves between departments manyfew Travel distanceslongershorter Travel pathsvariablefixed Job waiting timesgreatershorter Throughput timehigherlower Amount of work in process higherlower Supervision difficultyhigherlower Scheduling complexityhigherlower Equipment utilizationlowerhigher Functional vs. Cellular Layouts

36. Use of flexible manufacturing systems Service layouts Warehouse and storage layouts – Minimizing movement & picking time and cost Retail layouts – Presence & influence of customers Office layouts: – Information is computerized, image of openness Other Solutions & Service Layouts

37. Design Product Layouts: Line Balancing Line Balancing is the process of assigning tasks to workstations in such a way that the workstations have approximately equal time requirements. This way the idle time will be minimized, utilization will be maximized Specialzation: dividing work into elematal tasks that can be performed quickly and routinely

38. Cycle Time Cycle time is the maximum time allowed at each workstation to complete its set of tasks on a unit. t max < Cycle time < ∑t

39. Determine the Minimum Number of Workstations Required

40. A diagram that shows elemental tasks and their precedence requirements. A Simple Precedence Diagram a b cd e 0.1 min. 0.7 min. 1.0 min. 0.5 min.0.2 min. Precedence Diagram

41. Assume that the desired output is 480 units per day. The facility is workint 8 hours a day. The elemental tasks and their connections are shown in the previous slide. Calculate the cycle time. Calculate the minimum number of workstations. Arrange the tasks into these workstations in the order of the greatest number of following tasks. Example 1: Assembly Line Balancing

42. Workstation Time RemainingEligible Assign Task Revised Time Remaining Station Idle Time 11.0 0.9 0.2 a, c * c ** none*** ac-ac- 0.9 0.2 21.0bb0.0 31.0 0.5 0.3 de-de- de-de- 0.5 0.3 Total: 0.5 Example 1 Solution * Tasks that have no predecessors. ** b is not eligible, because it needs more time than than the remaining. *** Every available task needs more time than 0.2.

43. Efficiency = 1 – Percent idle time Calculate Percent Idle Time and efficiency

44. Line balancing procedure

45. Assign tasks in order of most following tasks. – Count the number of tasks that follow Assign tasks in order of task time. Assign tasks in order of greatest positional weight. – Positional weight is the sum of each task’s time and the times of all following tasks. Line Balancing Heuristics

46. Example 2 Working day is 8 hours and the desired output rate is 400 units per day. Draw the precedence diagram. Compute the cycle time & the minimum number of workstations required. Assign tasks to workstations according to the greatest number of following tasks. Tiebreaker: longest processing time goes first. Calculate Percent idle time & efficiency.

47. Other approaches Paralell workstations Cross-train workers (dynamic line balancing) Mixed model line (more product on the same line)

48. 1 min.2 min.1 min. 30/hr. 1 min. 60/hr. 30/hr. 60/hr. 1 min. 30/hr. Bottleneck Parallel Workstations

49. Thank you for your attention