oee-calculator

OEE Calculator

Overview

The OEE Calculator skill provides comprehensive capabilities for calculating and analyzing Overall Equipment Effectiveness. It supports availability, performance, and quality tracking, six big loss categorization, and world-class benchmarking.

Capabilities

• Availability calculation
• Performance rate tracking
• Quality rate measurement
• OEE trending and dashboards
• Six big loss categorization
• Pareto of losses
• Improvement target setting
• World-class benchmarking

Used By Processes

• LEAN-001: Value Stream Mapping
• SIX-002: Statistical Process Control Implementation
• CI-003: Benchmarking Program

Tools and Libraries

• MES integration
• OEE software
• Real-time dashboards
• Data collection systems

Usage

skill: oee-calculator
inputs:
  equipment: "CNC Machine 5"
  period: "2026-01-15"
  shift_data:
    planned_production_time: 480  # minutes
    downtime:
      - type: "breakdown"
        minutes: 30
      - type: "changeover"
        minutes: 20
    ideal_cycle_time: 0.5  # minutes per unit
    total_count: 800  # units
    good_count: 780  # units
outputs:
  - oee_score
  - availability
  - performance
  - quality
  - loss_breakdown
  - improvement_opportunities
  - trend_analysis

OEE Calculation

Formula

OEE = Availability x Performance x Quality

Where:
Availability = Run Time / Planned Production Time
Performance = (Total Count x Ideal Cycle Time) / Run Time
Quality = Good Count / Total Count

Example Calculation

Planned Production Time: 480 minutes
Downtime: 50 minutes
Run Time: 430 minutes
Ideal Cycle Time: 0.5 minutes
Total Count: 800 units
Good Count: 780 units

Availability = 430 / 480 = 89.6%
Performance = (800 x 0.5) / 430 = 93.0%
Quality = 780 / 800 = 97.5%

OEE = 89.6% x 93.0% x 97.5% = 81.3%

Six Big Losses

| Loss Category | OEE Factor | Examples |

|---------------|------------|----------|

| Breakdowns | Availability | Equipment failures |

| Setup/Adjustments | Availability | Changeovers, warm-up |

| Small Stops | Performance | Jams, minor issues |

| Reduced Speed | Performance | Running below ideal rate |

| Startup Rejects | Quality | Scrap during start-up |

| Production Rejects | Quality | In-process defects |

OEE Benchmarks

| OEE Level | Classification | Typical Range |

|-----------|----------------|---------------|

| World Class | Best in class | 85%+ |

| Good | Above average | 70-85% |

| Average | Typical | 60-70% |

| Low | Needs improvement | 40-60% |

| Poor | Significant issues | <40% |

World-Class Targets

| Factor | World Class | Typical |

|--------|-------------|---------|

| Availability | >90% | 85% |

| Performance | >95% | 90% |

| Quality | >99.9% | 98% |

| OEE | >85% | 60% |

Loss Analysis Process

1. Collect accurate loss data
2. Categorize by six big losses
3. Create Pareto chart
4. Focus on top losses
5. Apply appropriate methodology
6. Track improvement

Integration Points

• Manufacturing Execution Systems
• PLC/SCADA systems
• Quality Management Systems
• Maintenance management (CMMS)