IENG 471 - Lecture 03

1. IENG 471 - Lecture 03 Product & Process Design IENG 471 Facilities Planning

2. Product Design • Must meet the needs of the customer • QFD • Must be communicated (internally) • Product Drawings (Assembly, Detail) • Parts List • Part Structure • Indented BOM covers both the parts list and part structure IENG 471 Facilities Planning

3. Indented Bill of Materials • A “BOM” is a document that: • Lists all parts in an assembly • Shows the quantity of all components • Allows for the roll-up of costs • Shows the sequence of assembly • Each indentation shows the components of the sub-assembly IENG 471 Facilities Planning

4. Example: Manual Juicer IENG 471 Facilities Planning

5. Example: Manual Juicer IENG 471 Facilities Planning

6. Example: Manual Juicer • Function of the product: • Obtain seed-free juice from produce • Principle(s) of operation: • Lever (Class 2) to provide pressure • Grating to stop seeds • Gravity to drain the juice IENG 471 Facilities Planning

7. Example: Manual Juicer • Materials of construction: • Aluminum (sandcast) body • Rubber feet • Cost of the artifact: • $ 0.32 in aluminum • $ 0.04 in rubber • $ ??? in labor, shipping, packaging, etc. IENG 471 Facilities Planning

8. Example: Manual Juicer • Indented BOM & Cost Roll-up: (1) Juicer Assembly $ 0.36 (1) Body Sub Assembly $ 0.18 (1) Body Casting $ 0.14 (4) Rubber Feet $ 0.01 (1) Strainer Casting $ 0.05 (1) Lever Casting $ 0.10 (1) Hinge Pin $ 0.03 IENG 471 Facilities Planning

9. BOM Example in Excel IENG 471 Facilities Planning

10. Process Design • Steps in Process Identification • Define elemental operations • Identify alternative process(es) for each operation • Analyze alternative processes for each operation • Standardize processes for each operation • Evaluate alternative processes for overall production • Select processes for overall production IENG 471 Facilities Planning

11. Routing Example IENG 471 Facilities Planning

12. Operation Process Chart • Circles represent operations • Number in circle represents standard operation • Prefix in circle identifies: • Subassemblies (SA) – child levels • Assemblies (A) – parent level in this view • Circles are annotated with operation description • Boxes represent inspections • Number in box represents standard operation • Boxes are annotated with inspection description • Arcs (lines) represent component(s) • Arcs are annotated with part number & description for introduced components • (See Figure 2.12 in text, p. 44) IENG 471 Facilities Planning

13. Body Casting 4001 Rubber Feet 4021 Strainer Casting 4002 Lever Casting 4003 Hinge Pin 4004 Trim, inspect Trim, sand, inspect Trim, sand, inspect Trim, sand, inspect Trim, sand, inspect 0101 0101 0102 0101 0101 A1 SA1 I1 Plastic Bag 4031 A2 Example: Manual Juicer Operations-Process Chart IENG 471 Facilities Planning

14. Standard OPC Symbols IENG 471 Facilities Planning

15. Process Design Result • The result of the process design can be a precedence diagram: • Take the OPC and turn it on its’ side. Connect the component arcs with a single operation (START), and you have a Precedence Diagram • The precedence diagram can be converted to a PERT chart for SCHEDULE DESIGN IENG 471 Facilities Planning

16. 0101 4004 0101 4003 0100 0101 A1 I1 A2 4002 4021 0102 SA1 4001 0101 4031 Example: Manual Juicer Precedence Diagram IENG 471 Facilities Planning

17. PERT: Scheduling Terminology • Activity - A specific task or set of tasks that are required by the project, use up resources, and take time to complete • Event - The result of completing one or more activities. An identifiable end state occurring at a particular time. Events use no resources. • Network - The combination of all activities and events define the project and the activity precedence relationships Meredith, J. R. & Mantel, S. J. (2006) IENG 471 Facilities Planning

18. PERT: Scheduling Terminology • Path - The series of connected activities (or intermediate events) between any two events in a network • Critical - Activities, events, or paths which, if delayed, will delay the completion of the project. A project’s critical path is understood to mean that sequence of critical activities that connect the project’s start event to its finish event Meredith, J. R. & Mantel, S. J. (2006) IENG 471 Facilities Planning

19. L X Y Z Y Z X C M K A B PERT: Activity-on-Node Network Fundamentals J, K, & L can all begin atthe same time, if you wish(they need not occursimultaneously) J A is preceded by nothingB is preceded by AC is preceded by B but All (J, K, L) must becompleted before M canbegin (1) (3) Y and Z are preceded by X Z is preceded by X and Y Y and Z can begin at the same time, if you wish AA is preceded by X and Y AA (2) (4) Meredith, J. R. & Mantel, S. J. (2006) IENG 471 Facilities Planning

20. PERT: Activity on Node Notation Early Start (ES) Early Finish (EF) Activity Duration (D) Late Start (LS) Late Finish (LF) IENG 471 Facilities Planning

21. PERT: Calculating ES and EF • Forward Pass Through Network: • Move left to right, covering each simultaneous activity in order • ES = maximum of EF for all immediate predecessor activities (0 for START activity) • EF = ES + Duration • Critical Time = EF of the END activity IENG 471 Facilities Planning

22. PERT: Calculating LS and LF • Backward Pass Through Network: • Move right to left, covering each simultaneous activity in order • LF = minimum of LS for all immediate successor activities (Critical Time for END activity) • LS = LF – Duration • Slack (Float) Time: • LS – ES Note: Slack = 0 for Critical Activities IENG 471 Facilities Planning

23. PERT: Critical Path Example 1 4 4 5 5 6 B 3 F 1 G 1 3 6 6 7 7 8 0 1 1 4 8 9 9 11 C 3 A 1 H 1 Z 2 0 1 1 4 8 9 9 11 1 3 4 8 D 2 E 4 2 4 4 8 Critical Time = 11 sec Slack D = 1 sec Slack B, F, G = 2 sec Critical Path = A, C, E, H, Z IENG 471 Facilities Planning

24. PERT: Critical Path Management • CP are those activities where ES = LS • Any delay in these activities will delay production! • Wrong to say that these activities are the most important, though: • Frequently, activities with slack are put off until too late if not monitored! • Other paths may be near-critical, and will also delay the project if not monitored! IENG 471 Facilities Planning

25. Tying Critical Path to Facilities • Critical Path is connected to Makespan • If this were a repetitive operation environment: • Makespan is the total time for a single, physical unit to go through all operations • In manufacturing, the time difference between the start and finish of a sequence of jobs or tasks • In health care, the duration of a patient’s medical experience for a treatment episode • Team exercise • Suppose that you had to schedule people to produce a product • What would you do to operations on the CP? • What might you do with non-CP operations? Skorin-Kapov, J. & A. J. Vakharia IENG 471 Facilities Planning

26. Questions & Issues • HW 2: • Hands on assignment to develop: • BOM • Operations Process Chart • Precedence Diagram • Team exercise • Teams must be different from Project Teams • Semi-randomly assigned • 4 people per team (5 people, if necessary) • Other tools are in MIL Lab (IER 310) • Leave the tools there, but OK to take the product parts IENG 471 Facilities Planning