Friday, August 16, 2019
Donner Case
Order Size for drilling: * The Manual press needs 15 min for set up, in addition to 0. 08 min for every hole. Knowing that the typical circuit board has 500 drilled holes, then run time will be 0. 08*500 = 40 min / board. Therefore, time taken to drill N boards manually will be equal to : 15 + 40(N) * On the other hand the CNC drill needs 240 min for set up, in addition to 0. 004 min for every hole. So run time will be 0. 004*500 = 2 min / board.Then the time taken to drill N boards by CNC drill will be equivalent to : 240 + 2(N) * It is then logic to conclude that we will use CNC drill only in order sizes that will provide timing benefit over manual press. i. e. when 240 + 2N < 15 + 40N which means N 6 * However the shop floor policy dictates that only orders for more than 100 boards be drilled by CNC drill !!!!! Surely this must be changed * This means that they used the CNC drill in only 12 orders of the 60 orders received in September, while actually they should have used it in 3 5 orders ( all orders 6) !!Order Size for Profiling: * Set up time for Punch press is 50 min, while run time is 1 min / board. So Time taken to profile N orders will be 50 + N * While set up time for CNC routers reaches 150 min, in addition to 0. 5 min / board run time. So the time needed to complete profiling of N boards equals 150 + 0. 5(N) * Thus CNC reuters will produce time benefit if used only in orders more than 200 boards Capacity of Dry Film Photo Resist area: * Assuming order size equals 8 boards Then the panel preparation will take 5 + 0. = 5. 2 min Lamination & Exposure will take 20 + 2 = 22 min Development will take 20 + 0. 2 = 20. 2 min * This means that Lamination and exposure are the bottle neck of the process, and the cycle time for this step will be 22 min / panel. Which means that the capacity will be 2. 7 panels / hour * If we increased order size to 2 panels (16 boards) Panel preparation will take 5 + 0. 4 = 5. 4 min Lamination & Exposure will take 20 + 4 = 24 m in Development will take 20 + 0. 4 = 20. 4 min Lamination & exposure are still the bottle neck of the process, but the cycle time drops to 12 min / panel raising the capacity to 5 panels / hour.. Labor time for different order sizes: * Assuming four orders with one, eight, hundred and thousand boards each Operation| Setup| Run| One Board Order| Eight Board Order| Hundred Board Order| Thousand Boards order| PREPARATION| Ã | Ã | Ã | Ã | Ã | Ã | Artwork Generation| 29| 0| 29| 29| 29| 29| Inspect & Shear| 20| 0. 5| 20. 5| 20. 5| 26. 5| 82. 5| Punch Tooling Holes| 10| 0. 5| 10. 5| 10. 5| 16. 5| 72. | Ã | Ã | Ã | Ã | Ã | Ã | Ã | IMAGE TRANSFER| Ã | Ã | Ã | Ã | Ã | Ã | | Ã | Ã | Ã | Ã | Ã | Ã | Drill| Ã | Ã | Ã | Ã | Ã | Ã | Manual| 15| 0. 08| 55| Ã | Ã | Ã | CNC Drille| 240| 0. 004| Ã | 256| 440| 2240| Metallization| 10| 0. 75| 10. 75| 10. 75| 19. 75| 103. 75| Ã | Ã | Ã | Ã | Ã | Ã | Ã | Dry Film Photoresi st| Ã | Ã | Ã | Ã | Ã | Ã | 1. Panel| 5| 0. 2| 5. 2| 5. 2| 7. 6| 30| 2. Laminate & Expose| 20| 2| 22| 22| 46| 270| 3. Develop| 20| 0. 2| 20. 2| 20. 2| 22. 6| 45| Electroplate| 25| 8. 5| 33. 5| 33. 5| 135. 5| 1087. 5| Strip DFPR| 5| 0. 2| 5. 2| 5. 2| 7. 6| 30| Etch & Tin Strip| 10| 0. | 10. 2| 10. 2| 12. 6| 35| Ã | Ã | Ã | Ã | Ã | Ã | Ã | FABRICATION | Ã | Ã | Ã | Ã | Ã | Ã | | Ã | Ã | Ã | Ã | Ã | Ã | Soldermask| 45| 1. 5| 46. 5| 46. 5| 64. 5| 232. 5| Solder Dip| 30| 0. 5| 30. 5| 30. 5| 36. 5| 92. 5| | Ã | Ã | Ã | Ã | Ã | Ã | Profile| Ã | Ã | Ã | Ã | Ã | Ã | Punch Press| 50| 1| 51| 58| 150| Ã | CNC Router| 150| 0. 5| | | | 650| Inspect, Test, Pack| 45| 1. 5| 46. 5| 57| 145| 1545| | Ã | Ã | Ã | Ã | Ã | Ã | Total Labor Time| Ã | Ã | 397| 615| 1160| 6545| * Total Labor time is 397 minutes, 615 minutes, 1160 minutes, and 6545 minutes. * Large orders will best utilize the operationLabor distributio n for the operation considering minimum 8 boards per order: * One technician is assigned to inspection & shear, and Punch Tooling Holes Operation Time = 31 minutes * One technician is assigned to CNC drill, and MetallizationOperation Time = 27 minutes * One technician is assigned to panel prep, Develop, and Strip DFPROperation Time = 31 minutes * One technician is assigned to Laminate & Expose, and Etch & Tin StripOperation Time = 31 minutes * One technician is assigned to ElectroplatingOperation Time = 33. minutes * Two technicians are assigned to SoldermaskeOperation Time = 23 minutes * One technician is assigned to SolderdipOperation Time = 30. 5 minutes * Two technicians are assigned to Punch pressOperation Time = 25. 5 minutes * Two technicians are assigned to Inspect, test, packOperation Time = 24 minutes * Artwork generation, CNC drill diskettes, and CNC router diskettes are done with non productive stuff as soon as the order is issued and prior to the actual work start.Throu ghput rate for manufacturing process is equal to the largest operation time for processes = 34 min to produce a patch of eight boards Max idle time per technician is 10 minutes per patch Reduce lead time for order delivery: * Provide an initial inventory to reduce raw material delivery time * Provide a fixed schedule for operation to minimize bottlenecks and work piling * Assign experienced technicians for emergency rush orders, small sized orders, and return boards to perform work off the main production line. Introduce a job action sheet moving with every panel to check mark every finished process to eliminate any returned work due to unperformed processes. * For any stoppage order a complete reschedule for the complete order is mandatory * Create a WIP and schedule sheet visual for the president and sales department to consider while planning for a bid *
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