Plastic Production Planning

Cheatsheet Content

I. Core Production Planning Concepts Master Production Schedule (MPS): High-level plan for specific products, quantities, and dates. Drives MRP. Material Requirements Planning (MRP): Calculates raw material and component needs based on MPS and BOM. Capacity Requirements Planning (CRP): Assesses if available resources (machines, labor) can meet production demand. Shop Floor Control (SFC): Manages and monitors production orders on the factory floor. Just-In-Time (JIT): Minimize inventory by producing only what is needed, when it is needed. Lean Manufacturing: Focuses on eliminating waste (Muda) in all forms. II. Key Data for Excel Sheet A. Product & Bill of Materials (BOM) Product ID: Unique identifier (e.g., PROD-001 ) Product Name: (e.g., "Plastic Bottle 500ml") Standard Cycle Time: Time per unit (e.g., "15 seconds/unit") BOM Structure: Component ID: (e.g., RESIN-001 , CAP-002 ) Component Name: (e.g., "PET Resin", "Screw Cap") Quantity per Unit: How much of each component for one finished product (e.g., "0.02 kg", "1 pc") Unit of Measure (UoM): (e.g., "kg", "pcs", "grams") B. Inventory Data Raw Material Inventory: Material ID , Current Stock , Safety Stock , Lead Time (days) , Supplier Finished Goods Inventory: Product ID , Current Stock , Safety Stock C. Production Resources & Capacity Machine ID: (e.g., INJ-M-01 - Injection Molding Machine 01) Machine Type: (e.g., "Injection Molding", "Extrusion", "Blow Molding") Available Hours/Day: (e.g., "20 hours" for 2 shifts) Maintenance Schedule: Planned downtime. Labor: Available shifts, skill sets. D. Sales Orders/Demand Forecast Order ID: (e.g., SO-001 ) Product ID: Quantity Ordered: Due Date: Forecasted Demand: (per product, per period) III. Excel Sheet Structure & Formulas A. MPS Sheet (Master Production Schedule) Week/Date Product A Demand Product A Forecast Product A MPS Product B Demand ... Wk 1 1000 950 1000 500 ... Wk 2 - 1100 1100 600 ... Formulas: MPS = MAX(Demand, Forecast) - Current_FG_Stock (adjust for safety stock) B. BOM & Material Requirements Sheet Product ID Component ID Qty per Product UoM Weekly MPS (from MPS sheet) Total Component Req. Current Stock Net Req. Order Qty Order Date PROD-001 RESIN-001 0.02 kg kg 1000 (Wk 1) 20 kg 50 kg 0 kg 0 kg - PROD-001 CAP-002 1 pc pcs 1000 (Wk 1) 1000 pcs 200 pcs 800 pcs 800 pcs (Due Date - Lead Time) Formulas: Total Component Req. = Qty per Product * Weekly MPS Net Req. = MAX(0, Total Component Req. - Current Stock) Order Qty = Net Req. (adjust for supplier MOQ/batch size) C. Capacity Planning Sheet Machine ID Machine Type Available Hrs/Day Prod. Orders (Units) Total Cycle Time (Hrs) Required Hrs Available Hrs (Weekly) Capacity Utilization Overload/Underload INJ-M-01 Injection 20 1000 (PROD-001) (1000*15/3600) 4.17 hrs 100 hrs 4.17% Underload Formulas: Total Cycle Time (Hrs) = SUM(Units_from_MPS * Cycle_Time_per_Unit / 3600) Available Hrs (Weekly) = Available Hrs/Day * 5 (or 7) Capacity Utilization = Required Hrs / Available Hrs (Weekly) Overload/Underload = Available Hrs - Required Hrs IV. Optimization & Considerations Batch Sizing: Determine optimal production batch sizes to balance setup costs and inventory holding costs. Changeover Times: Account for time lost changing molds/setups between different products. Scrap Rates: Factor in expected material loss during production. Adjust material requirements accordingly. Machine Downtime: Plan for preventive maintenance and unexpected breakdowns. Bottleneck Identification: Use capacity planning to identify overloaded machines/processes. Supplier Reliability: Consider supplier lead time variability and quality. Data Validation: Use Excel's data validation features to ensure consistent data entry (e.g., dropdowns for Product IDs). Conditional Formatting: Highlight critical values (e.g., low stock, overloaded capacity, overdue orders). Solver Add-in: For complex optimization problems (e.g., minimizing costs, maximizing throughput). V. Metrics & KPIs On-Time Delivery (OTD): Percentage of orders delivered by due date. Production Attainment: Actual production vs. planned production. Capacity Utilization: Percentage of available capacity used. Inventory Turnover: How many times inventory is sold/used in a period. Scrap Rate: Percentage of material wasted. Lead Time: Time from order placement to delivery.