Field notes and methods

Guides for making a calculation operational.

These guides explain method choice, definition boundaries, and questions to ask before a metric becomes a decision.

Test learning

Reliability growth and Duane model

Plan and interpret a power-law growth program.

Accelerated testing

Accelerated life testing model selection

Match stress models to failure mechanisms and test decisions.

Metrics

MTBF vs MTTF vs MTTR

Definitions, use cases, and common misuse.

Readiness

Equipment availability

Choose the correct availability boundary.

Architecture

Reliability block diagrams

Model success paths and dependencies.

Life data

Understanding Weibull analysis

Shape, characteristic life, and uncertainty.

Performance

OEE loss categories

Turn a score into loss ownership.

Economics

Downtime cost framework

Build a traceable consequence model.

Decision

Repair vs replace framework

Compare future risk and economics.

MRO

MRO safety stock planning

Balance service risk and carrying cost.

Work management

Maintenance planning and scheduling

Keep planning, scheduling, execution, and review distinct.

Maintenance data

CMMS data readiness

Build trustworthy asset and work-order records before relying on KPIs.

Fault investigation

Intermittent fault and NFF investigation

Preserve transient evidence, compare history, and prepare bounded reproduction tests.

MRO forecasting

Intermittent spare-parts forecasting

Audit sparse history, validate baselines, and govern planner overrides.

Operating exposure

Equipment operating profile analysis

Reconstruct state, load, excursion, and rate evidence before interpretation.

Method before dashboard.

Use a calculator to make arithmetic transparent, then use a guide to test its decision boundary. The reference desk keeps core definitions close at hand.