Download to read offline
MANUFACTURING RESOURCE PLANNING Basics and concepts
- 1.
- 2. Hierarchical Planning Process HierarchicalPlanning Process Items Items Product lines Product lines or families or families Individual Individual products products Components Components Manufacturing Manufacturing operations operations Resource Resource Level Level Plants Plants Individual Individual machines machines Critical Critical work work centers centers Production Production Planning Planning Capacity Capacity Planning Planning Resource requirements plan Rough-cut capacity plan Capacity requirements plan Input/ output control Aggregate production plan Master production schedule Material requirements plan Shop floor schedule All All work work centers centers Figure 9.5 Figure 9.5 Forecast Forecast
- 3. Material Requirements Material Requirements Planning Planning Computerized inventory control & Computerized inventory control & production planning system production planning system Schedules component items when Schedules component items when they are needed - no earlier and no they are needed - no earlier and no later later
- 4. STRUCTURE OF MRP STRUCTUREOF MRP Material requirements planning Planned order releases Work orders Purchase orders Rescheduling notices Item master file Product structure file Master production schedule Figure 12.5 Figure 12.5
- 5. Master Production Master Production Schedule Schedule Drives MRP process with a schedule of Drives MRP process with a schedule of finished products finished products Quantities represent production not Quantities represent production not demand demand Quantities may consist of a combination of Quantities may consist of a combination of customer orders & demand forecasts customer orders & demand forecasts Quantities represent what needs to be Quantities represent what needs to be produced, not what can be produced produced, not what can be produced
- 6. Master Production Master Production Schedule Schedule PERIOD PERIOD MPSITEM MPS ITEM 1 1 2 2 3 3 4 4 5 5 Clipboard Clipboard 85 85 95 95 120 120 100 100 100 100 Lapdesk Lapdesk 0 0 50 50 0 0 50 50 0 0 Lapboard Lapboard 75 75 120 120 47 47 20 20 17 17 Pencil Case Pencil Case 125 125 125 125 125 125 125 125 125 125
- 7. BILL OF MATERIAL BILLOF MATERIAL (BOM) (BOM) Top clip (1) Bottom clip (1) Pivot (1) Spring (1) Rivets (2) Finished clipboard Pressboard (1) Clipboard
- 8. Product Structure Tree ProductStructure Tree Clipboard Level 0 Level 0 Level 1 Level 1 Level 2 Level 2 Spring (1) Bottom Clip (1) Top Clip (1) Pivot (1) Rivets (2) Clip Ass’y (1) Pressboard (1)
- 9. INVENTORY RECORD FILE INVENTORYRECORD FILE DESCRIPTION DESCRIPTION INVENTORY POLICY INVENTORY POLICY Item Item Pressboard Pressboard Lead time Lead time 1 1 Item no. Item no. 734 734 Annual demand Annual demand 5000 5000 Item type Item type Purch Purch Holding cost Holding cost 1 1 Product/sales class Product/sales class Comp Comp Ordering/setup cost Ordering/setup cost 50 50 Value class Value class B B Safety stock Safety stock 0 0 Buyer/planner Buyer/planner RSR RSR Reorder point Reorder point 39 39 Vendor/drawing Vendor/drawing 07142 07142 EOQ EOQ 316 316 Phantom code Phantom code N N Minimum order qty Minimum order qty 100 100 Unit price/cost Unit price/cost 1.25 1.25 Maximum order qty Maximum order qty 500 500 Pegging Pegging Y Y Multiple order qty Multiple order qty LLC LLC 1 1 Policy code Policy code 3 3 Table 12.4 Table 12.4
- 10. Item Master File ItemMaster File PHYSICAL INVENTORY PHYSICAL INVENTORY USAGE/SALES USAGE/SALES CODES CODES On hand On hand 100 100 YTD usage/sales YTD usage/sales 1100 1100 Location Location W142 W142 MTD usage/sales MTD usage/sales 75 75 On order On order 100 100 YTD receipts YTD receipts 1200 1200 Allocated Allocated 75 75 MTD receipts MTD receipts 0 0 Cycle Cycle 3 3 Last receipt Last receipt 8/25 8/25 Last count Last count 9/5 9/5 Last issue Last issue 10/5 10/5 Difference Difference -2 -2 Cost acct. Cost acct. 00754 00754 Routing Routing 00326 00326 Engr Engr 07142 07142 Table 12.4 Table 12.4
- 11. Basic MRP Basic MRP Processes Processes 1. 1.Exploding the bill of material Exploding the bill of material 2. 2. Netting out inventory Netting out inventory 3. 3. Lot sizing Lot sizing 4. 4. Time-phasing requirements Time-phasing requirements
- 12. The MRP Matrix TheMRP Matrix Gross Requirements Gross Requirements Derived from MPS or planned Derived from MPS or planned order releases of the parent order releases of the parent Scheduled Receipts Scheduled Receipts On order and scheduled to be On order and scheduled to be received received Projected on Hand Projected on Hand Beg Inv Beg Inv Anticipated quantity on hand at Anticipated quantity on hand at the end of the period the end of the period Net Requirements Net Requirements Gross requirements net of Gross requirements net of inventory and scheduled inventory and scheduled receipts receipts Planned Order Receipts Planned Order Receipts When orders need to be When orders need to be received received Planned Order Releases Planned Order Releases When orders need to be placed When orders need to be placed to be received on time to be received on time ITEM NAME OR NO. ITEM NAME OR NO. LLC - LOW LEVEL CODE LLC - LOW LEVEL CODE PERIOD PERIOD LOT SIZE QTY MADE IN LOT SIZE QTY MADE IN LT - LEAD TIME LT - LEAD TIME 1 1 2 2 3 3 4 4 5 5 Table 12.5 Table 12.5
- 13. Basic MRP formulas BasicMRP formulas • Net Requirements = Gross Requirements – scheduled receipts – On-hand Inventory(previous period) • Planned Order Receipt = function (Net Requirements, order policy) • Planned Order Release = Planned Order Receipt backed up by the lead time – Planned Order Releasei-LT = Planned Order Receipti
- 14. More formulas More formulas •On-hand inventoryi = on-hand inventoryi-1 + scheduled receiptsi + Planned Order Releasei – Gross Requirementsi • Gross Requirements for next level down are determined from the Planned Order Releases at the level above
- 15. On-hand inventory On-hand inventory •Is always the amount of on-inventory at the end of the period • All other items (gross req., net req., scheduled receipts, planned order receipts) are amounts at the beginning of the period
- 16. MRP Outputs MRP Outputs Planned orders Planned orders Work orders Work orders Purchase orders Purchase orders Changes to previous plans or Changes to previous plans or existing schedules existing schedules Action notices Action notices Rescheduling notices Rescheduling notices
- 17. Planned Order Report PlannedOrder Report Table 12.6 Table 12.6 Item Item #2740 #2740 Date Date 9 - 25 - 02 9 - 25 - 02 On hand On hand 100 100 Lead time Lead time 2 weeks 2 weeks On order On order 200 200 Lot size Lot size 200 200 Allocated Allocated 50 50 Safety stock Safety stock 50 50 SCHEDULED SCHEDULED PROJECTED PROJECTED DATE DATE ORDER NO. ORDER NO. GROSS REQS. GROSS REQS. RECEIPTS RECEIPTS ON HAND ON HAND ACTION ACTION 50 50 9-26 9-26 AL 4416 AL 4416 25 25 25 25 9-30 9-30 AL 4147 AL 4147 25 25 0 0 10-01 10-01 GR 6470 GR 6470 50 50 - 50 - 50 10-08 10-08 SR 7542 SR 7542 200 200 150 150 Expedite SR 10-01 Expedite SR 10-01 10-10 10-10 CO 4471 CO 4471 75 75 75 75 10-15 10-15 GR 6471 GR 6471 50 50 25 25 10-23 10-23 GR 6471 GR 6471 25 25 0 0 10-27 10-27 GR 6473 GR 6473 50 50 - 50 - 50 Release PO 10-13 Release PO 10-13 Key: Key: AL AL = allocated = allocated WO WO = work order = work order CO CO = customer order = customer order SR SR = scheduled receipt = scheduled receipt PO PO = purchase order = purchase order GR GR = gross requirement = gross requirement
- 18. MRP Action Report MRPAction Report Table 12.7 Table 12.7 Current date 9-25-02 Current date 9-25-02 ITEM ITEM DATE DATE ORDER NO. ORDER NO. QTY. QTY. ACTION ACTION #2740 #2740 10-08 10-08 7542 7542 200 200 Expedite Expedite SR SR 10-01 10-01 #3616 #3616 10-09 10-09 Move forward Move forward PO PO 10-07 10-07 #2412 #2412 10-10 10-10 Move forward Move forward PO PO 10-05 10-05 #3427 #3427 10-15 10-15 Move backward Move backward PO PO 10-25 10-25 #2516 #2516 10-20 10-20 7648 7648 100 100 De-expedite De-expedite SR SR 10-30 10-30 #2740 #2740 10-27 10-27 200 200 Release Release PO PO 10-13 10-13 #3666 #3666 10-31 10-31 50 50 Release Release WO WO 10-24 10-24
- 19.
- 20. DEFINITION OF MRP-II& DEFINITION OF MRP-II & ITS FUNCTIONING ITS FUNCTIONING • MRP II stands for Manufacturing Resources Planning, a computer modelling technique for analysing and controlling complicated Manufacturing operations • When the manufacturing data has been collected (parts, assemblies, resources) the lead time and cost of every component can be predicted under any manufacturing conditions. • As soon as an order is received the workload on the manufacturing organisation and the delivery time can be calculated.
- 21. • MRP IIsystems also keep track of customers, suppliers and accounting functions. • Inventory can be purchased and assemblies made "Just in Time". The records kept by an MRP system highlight inadequacies such as overloaded production centres and delays by suppliers. • The effect of new orders, changes in capacity, shortages, delays and a myriad of other disturbances are calculated and tracked with confidence.
- 22. HOW MRP-II WORKS HOWMRP-II WORKS Forecast Aggregate production plan Customer orders Feasible? Master production schedule Material requirements planning Capacity requirements planning Feasible? Purchase orders Work orders Inventory Shop floor control Manufacture No No Yes Yes Feedback Feedback No No Yes Yes
- 23. BENEFITS OF MRP-II BENEFITSOF MRP-II - Reduced inventory. - Accurately predicted delivery times. - Accurate costing at every stage of the manufacturing process. - Improved use of manufacturing facilities. - Faster response to changing conditions. - Control of every stage of production