6Three General Approaches to Production Make-to-stock: Items produced in anticipation of orders, often from a sales forecast (DiGiorno frozen pizza, Miller Lite beer)Make-to-order: Items produced to meet specific customer orders (Boeing 737s for Southwest Airlines)Assemble to order: Final product assembled from make-to-stock items (Dell desk top computer)IDES Manufacturing uses a “Make-to-stock” approach. Production of ore wagons will be driven by a sales forecast.
7Sales and Operations Planning. The “Rough-Cut” Plan screen for the SAP Sales and Operations Planning The “Rough-Cut” Plan screen for the SAP R/3 system. Sales and Operations Planning Jan Feb Mar Apr May 1) Sales Forecast ) Production Plan 3) Stock Level ) Working Days ) Capacity ) Utilization 55% 70% 73% 91% 78% 7) T-W101 (units) % ) T-W102 (units) % ) T-W103 (units) %
9Independent versus Dependent Demand Independent demand - demand for item is independent of demand for any other itemThe TW101A is an example of an independent demand item. It is scheduled for production as a result of a sales forecast.Dependent demand - demand for item is dependent upon the demand for some other itemThe TWB101A is an example of a dependent demand item. It is scheduled to be purchased because of the demand for its parent, the TW101A ore wagon.
10MRP Systems - Input and Output MasterProductionScheduleBill ofMaterialsMaterialRequirementsPlanning SystemInventoryStatusPlanned Order& OtherReportsItem MasterPurchasingDataIt is helpful here to briefly review the “contents” of each of the boxes - i.e., what is contained in an Item Master file, what purchasing data is expected, etc.
11Structure of the MRP System MRP by period reportMRP by date reportPlanned orders reportPurchase requirementsException reportsMRPProgramsMaster ProductionScheduleBOMLead Times(Item Master File)(Bill-of-Material)Inventory DataPurchasing dataEmphasize that this slide illustrates the overall technological structure of MRP - people and process are also extremely important in its actual success.
12Lead Times and Lot Sizing The BOM is used to determine how many of each component is required to produce a “parent”. For example, one wagon bed and two axle assemblies are required to produce on ore wagon (parent). Two wheels and one axle are required to produce one axle assembly (parent).To determine the timing and quantity for the purchase orders for the components requires information about lead-times and lot-sizing. This is found in the Material Master File (Item Master): Material Master File for T-W101A (Ore Wagon)Component Description Vendor Lot Size Lead TimeT-W101A Ore Wagon Internal Fabrication LFL 5 DaysT-WB101A Wagon Bed Minnesota Mfg Days T-AA101 Axle Assembly Internal Fabrication Days T-AX101 Axle Sooner Milling Days T-WH101 Wheel Minnesota Mfg Days
13Master Production Schedule The production plan starts with the Sales Forecast for the month of April. This is broken down into a Detailed Production Schedule for each week. Earlier, we determined that the total demand in April for model T101A is IDES Marketing Department wants these to be available for shipment at the end of each week as shown below. Model Week Week Week Week 17 T-W101A Once this has been agreed to, it becomes the Master Production Schedule (MPS).
14Information from the Material Master File T-W101A IDES Mfg has determined that the cost effective way to fabricate the ore wagon is to make exactly the number that are required. If 50 are needed, then make 50; If 38 are needed, then make 38. This is called “lot-for-lot” sizing (“Lot Size” = LFL). It takes 5 days to make ore wagons (“Lead-Time” = 5 days).T-WB101A IDES Mfg has determined that the cost effective way to purchase the wagon bed is to order in quantities of 200 (“Lot Size = 200). It takes 10 days to receive an order after it has been placed (“Lead Time = 10 days).
15The “MRP Record” for T-W101A Week 14: Independent Requirements 50Scheduled Receipts 0Projected on Hand (BI) 0Net Requirements 50Planned Order Receipts 50 (LFL)Planned Order Release ?To fabricate wagons in Week 14, a Planned Order Release must be made at the beginning of Week 14 (Lead Time = 5 days)Week 15: Independent Requirements 25Projected on Hand (BI)Net Requirements 25Planned Order Receipts 25 (LFL)
16The “MRP Record” for T-WB101A (Wagon Bed) Week 14: Dependent Requirements 50Scheduled Receipts 0Projected on Hand (BI) 0Net Requirements 50Planned Order Receipts (Lot Size)Planned Order Release ?To receive 200 wagon beds at the beginning of Week 14, a “Planned Order Release” must be made at the beginning of Week 12 (Lead Time = 10 days)Week 15: Dependent Requirements 25Projected on Hand (BI)Net Requirements 0Planned Order Receipts 0There are zero (0) net requirements in Week 15. No wagon beds must be received in Week 15. No Planned Order Release is necessary.
17Homework AssignmentBased on the Master Production Schedule for April 2003, complete the Material Requirements Planning for all materials.Have this assignment ready to turn in at the beginning of class on ThursdayMarch 13th.