Production Capacity Constraint & Bottleneck Analyzer
Identify production bottlenecks, calculate system capacity using Theory of Constraints for throughput optimization
Worked Examples
Example 1: Manufacturing Line Capacity Analysis
Problem: 4-station line: Cutting 100/hr, Assembly 80/hr, QC 120/hr, Packing 90/hr. Current load 85/hr. Target 100/hr. Can we meet target?
Solution: Capacity Analysis:\n- Cutting: 100/hr capacity, 85/hr load (85% utilization)\n- Assembly: 80/hr capacity, 85/hr load (106% - IMPOSSIBLE)\n → Actual load limited to 80/hr\n- QC: 120/hr capacity, 85/hr load (71%)\n- Packing: 90/hr capacity, 85/hr load (94%)\n\nBottleneck: Assembly (80/hr)\n - Lowest capacity\n - Limits entire system to 80/hr\n\nCurrent Output: 80/hr (system capacity)\nTarget: 100/hr\nGap: 20/hr (25% short)\n\nCan meet target? NO\n- Assembly constrains to 80/hr\n- Must increase Assembly capacity by 20/hr (+25%)\n\nOptions:\n\nOption 1: Upgrade Assembly\n- Add equipment or worker\n- Increase 80 → 100/hr\n- Cost: $50K (new station)\n- New bottleneck: Packing (90/hr)\n- System capacity: 90/hr (still short 10/hr)\n- Need to also upgrade Packing 90 → 100\n- Additional cost: $30
Result: System capacity: 80/hr (Assembly bottleneck) | Target: 100/hr (25% short) | Need $25K to reach 90/hr via Assembly + Packing optimization
Frequently Asked Questions
What is a production bottleneck?
Bottleneck is the slowest step in production process limiting overall output. Example: Assembly line has Cutting (100/hr), Assembly (80/hr), Packing (120/hr). Assembly is bottleneck (80/hr). System can only produce 80/hr regardless of other stations' capacity. Theory of Constraints (Goldratt): System output = bottleneck capacity. Improving non-bottleneck stations doesn't increase output. Only improving bottleneck does.
How do I identify bottleneck?
Methods: (1) Observation (queue builds up before bottleneck station), (2) Utilization (station running at 95-100% while others are 60-70%), (3) Cycle time (longest processing time), (4) WIP (work-in-progress accumulates before bottleneck). Example: Parts pile up before Assembly (queue = bottleneck). Assembly workers never idle (high utilization). Other stations have downtime. Assembly is bottleneck. Measure capacity at each stage; lowest capacity = bottleneck.
Should I optimize bottleneck or non-bottleneck?
Always optimize bottleneck first. Theory of Constraints: Hour lost at bottleneck = hour lost for entire system. Hour saved at non-bottleneck = meaningless (just creates more idle time). Example: Assembly (bottleneck) produces 80/hr. Cutting produces 100/hr. Improving Cutting to 120/hr changes nothing (Assembly still limits to 80). Improving Assembly to 90/hr increases system output to 90/hr (+12.5%). Focus: Bottleneck utilization (keep it running), non-bottleneck subordination (support bottleneck).
What happens when I eliminate bottleneck?
Eliminating bottleneck reveals next bottleneck. Example: Assembly 80/hr (bottleneck). Upgrade to 100/hr. Now Packing (90/hr) becomes bottleneck. System capacity: 80 → 90 (+12.5%). Continuous improvement: Identify bottleneck → Improve → New bottleneck emerges → Repeat. Never-ending. But diminishing returns eventually: improving capacity from 80 to 200 may not be valuable if demand is only 150. Match capacity to demand, not infinite optimization.
How do I calculate production capacity?
Capacity = Bottleneck capacity (units/time). Example: Assembly line with 5 stations: A (100/hr), B (80/hr), C (90/hr), D (120/hr), E (85/hr). Bottleneck: B (80/hr). System capacity: 80/hr. Daily capacity (8 hours): 640 units. Accounting for: Downtime (10% breaks, maintenance), efficiency (85% actual vs. theoretical) → Effective capacity: 640 × 0.9 × 0.85 = 490 units/day. Use effective capacity for planning (not theoretical).
What is the cost of bottleneck downtime?
Bottleneck downtime stops entire system. Example: Assembly (bottleneck 80/hr) down for 1 hour. Lost output: 80 units. At $50 profit/unit = $4,000/hour. Non-bottleneck downtime: Only affects that station. Cutting down 1 hour = 0 lost output (Assembly still runs from WIP buffer). Prioritize: Preventive maintenance on bottleneck (minimize downtime), backup for bottleneck (redundancy), less maintenance on non-bottleneck (tolerate occasional downtime).