IENG 471 - Lecture 06

1. IENG 471 - Lecture 06 Flow: Quantitatively and Qualitatively Measured IENG 471 Facilities Planning

2. Depends on cell production rate and on production control policy for material flow Space Considerations • Equipment footprint • Utilities space • Maintenance space • Operating space • (Operator space is discussed AFTER Exam I) • Material space • Tooling space • Scrap space • Work-In-Process (WIP) • Receiving Space • Shipping Space • Plus Material Transportation! IENG 471 Facilities Planning

3. Production Control of Flow • Push Production: • Traditional • Build To Schedule • Cell Efficiency Effects – Optimal • Overall Efficiency Effects – Sub-Optimal • Pull Production: • JIT • Kanban • Production Card (POK) • Withdrawal Card (WLK) • Minimizes WIP (and a host of other problems!) IENG 471 Facilities Planning

4. Flow Factors • What makes moving a thing difficult? • Shape awkward/compact • Weight mass per unit • Size L x W x H • Value wood / gold • Fragility delicate / sturdy • Condition sticky / hot / wet / frozen • Equipment fork truck / cart / crane • Distance short / long / elevation change IENG 471 Facilities Planning

5. Flow Intensity • Four Basic Factors of All Moves (Phillips) • Materials • Methods of handling • Moves (distance & elevations) • Money cost of mfg. philosophy cost of materials movement cost of handling equipment IENG 471 Facilities Planning

6. Flow – Quantitative • Equivalent Load Unit • Accounts for volume and method • Approximates cost (macro-level) • ELUs become the unit of measure for flow between pairs of areas (dept.s) • Flow is tracked on a square matrix • Seek to minimize the sum of the flow volume and distance product for each pair of areas IENG 471 Facilities Planning

7. From – To Chart • Similar to Map Mileage Charts: • Matrix of Departments (Mfg. Cells) • Cell entries quantify flow AND direction of flow between departments • Steps to Create: • List departments in OPC sequence • From department is listed vertically • To department is listed horizontally • Establish Equivalent Load Unit measure • Distance Qty Cost/Trip* • Record flow volume in chart • Above diagonal is forward flow • Below diagonal is back-track flow IENG 471 Facilities Planning

8. Data Collection: From – To Chart • Set up a spreadsheet with extra wide / tall cells • Define ELU units between departments • Could be different in each cell! • Use tally marks to track trips • Could scale for high trip counts • Final tally is ELU trips per unit time IENG 471 Facilities Planning

9. From – To Chart: Flow Qty • Order according to OPC flow • Above diagonal is forward flow: • From Dept. is on Left • To Dept. is on top • ELU volume (number of trips) is entered in the cell • Below diagonal is back flow: • Often rework / scrap IENG 471 Facilities Planning

10. Flow – Qualitative • Closeness Ratings • Accounts for info transfer & contact frequency and intangibles … • Noise tolerance, control needs, aesthetics, security, dirt control, safety issues, etc. • Rating Scale for closeness: • A – absolutely necessary • E – especially important • I – important • O – ordinary closeness OK • U – unimportant to be close • X – closeness is not desirable • Examples: • Machining Center for magnesium parts and: • First aid station • Raw materials supply for the center • Fire suppression station • Packaging (cardboard) storage • Next workstation on Operations Process Chart if next operation is • Assembly • Inspection • Liquid paint IENG 471 Facilities Planning

11. Relationship Chart • Qualitative Flow • Obtained from Interviews • List departments • Conduct interviews • Define criteria • Establish relationship value & reason for all pairs • Review chart with ALL involved parties for evaluation & discussion IENG 471 Facilities Planning

12. Relationship Chart - Example IENG 471 Facilities Planning

13. Evaluating Flow Information IENG 471 Facilities Planning

14. Estimating Dept. Space • Space must be allowed for the activities carried out in the departments • Typical Information to capture for Equipment: • Machine Data (manufacturer, type, model, s/n) • Location of safety stops (big red buttons, …) • Floor loading (weight of machine) • Height, width, depth (static – non-operating) • Maximum operating travel (up, left, right, back, fwd) • Maintenance space and location (remove & repair) • Plant service spaces and locations (utilities) IENG 471 Facilities Planning

15. Estimating Dept. Space • Space must be allowed for the activities carried out in the departments • Typical Information to capture for Materials: • Receiving and In-bound storage • Work In-Process • Out-bound storage and Shipping • Waste storage and Shipping • Storage for unused tools, fixtures, jigs, … • Storage for maintenance equipment IENG 471 Facilities Planning

16. Estimating Dept. Space • Space must be allowed for the activities carried out in the departments • Typical Information to capture for Operators: • Operator while working • Operator while resting • Operator while handling material • Operator while entering (ingress) and leaving (egress) • Remember Ergonomic considerations! IENG 471 Facilities Planning

17. Space – Production Floor • Personnel need space for: • Operating equipment • Dependent on operation • Interview operators, observe similar cells • Material Handling • Dependent on material and sizes • See Tables 3.3 & 3.4 (see next slide) from Bozier, et. al. • Ingress & Egress • Dependent on safety, equipment footprint: • 30 inches between static objects • 36 inches between static object & operating equipment • 42 inches between two operating pieces of equipment IENG 471 Facilities Planning

18. Estimating Aisle Space • Flow Analysis allows us to estimate space required for the materials going through the departments • Also need to allow for space for moving materials moving between departments • Typically, this is based on the size of the From department (footprint), the size (of load) and the method of movement (equipment size) IENG 471 Facilities Planning

19. Aisle Space Example • Assume a reaction-injection molding (RIM) cell handling car bumpers: • Cell dimension is 50 ft x 15 ft = 750 ft2 • Bumper size is 6 ft x 1 ft = 6 ft2 • Aisle is desired between two operating cells (lengthwise): • Using Table 3.3: (15%)(750 ft2) = 2.25 ft = 27 inches 50 ft • But, subject to OSHA, use the 42 inch width between operating equipment! IENG 471 Facilities Planning

20. Aisle Space Example – Cont. • Assume a RIM cell handling car bumpers – and a pallet of bumpers at the end of the cell that is moved by a pallet-jack (manual platform truck) • Using Table 3.4: Aisle width is 5 ft = 60 inches • OSHA Requirement: 42 inches (worst case) – met! • Bumper size is 6 ft x 1 ft: so increase to 6 ft = 72 inches • But, the aisle is blocked while loading pallet, must allow for two-way flow of bumper pallets: so increase to 2 x 6 ft = 144 inches • And then add some space for clearance! IENG 471 Facilities Planning

21. Questions & Issues IENG 471 Facilities Planning