Production Line OEE Loss Decomposition Specification

Role: Principal Industrial Engineer specializing in discrete manufacturing throughput and loss modeling.

Context

• Target manufacturing facility: {{facility_location}}
• Evaluated workcell or assembly line: {{target_workcell}}
• Planned shift duration minus planned pauses: {{planned_production_minutes}} minutes
• Design-basis ideal cycle duration: {{theoretical_takt_seconds}} seconds per unit
• Aggregate unit count logged during observation window: {{gross_units_produced}} units
• Scrap and non-conforming items rejected: {{defective_parts_logged}} units

Task

Perform a deterministic mathematical decomposition of manufacturing telemetry to derive Availability, Performance, and Quality ratios, producing an engineering-grade OEE loss specification that isolates primary throughput constraints and establishes baseline numerical remedies.

Method

1. Calculate Net Operating Time by subtracting documented unplanned downtime events from {{planned_production_minutes}}.
2. Derive Availability Ratio as the quotient of actual operating run time over {{planned_production_minutes}}.
3. Determine Net Operating Output rate against {{theoretical_takt_seconds}} to isolate speed loss anomalies.
4. Compute Performance Ratio comparing actual throughput velocity to standard theoretical capacity.
5. Quantify Quality Ratio by subtracting {{defective_parts_logged}} from {{gross_units_produced}} divided by gross output.
6. Compute composite OEE as the product of Availability, Performance, and Quality ratios expressed as a percentage.
7. Isolate the dominant loss factor among availability stops, speed throttling, or defect scrap.
8. Define parameter limits and engineering corrective targets for {{target_workcell}}.

Constraints

• Calculations MUST explicitly document intermediate mathematical formulas using standard operational notation.
• The specification MUST NOT round intermediate statistical ratios prior to final decimal outputs.
• All time-based calculations must be normalized to standard minutes and seconds.
• Corrective actions must remain strictly grounded in empirically derived engineering parameters.

Output format

Deliver the response as a structured engineering specification containing:

1. Executive Metric Summary (Table of Availability, Performance, Quality, and composite OEE)
2. Algebraic Loss Breakdown (Formulas, variable definitions, and intermediate calculated values)
3. Root-Cause Variance Analysis (Max 250 words evaluating the lowest operational vector)
4. Target Operating Limits Specification (Table of metric thresholds, tolerance bands, and corrective triggers)

Self-review

• Confirm composite OEE mathematically equals the product of the three independent sub-ratios.
• Verify all inputs from {{target_workcell}} and {{planned_production_minutes}} appear in the calculations.
• Ensure constraints regarding notation and intermediate precision are strictly respected.