OptimalIntegrity Studio™ Wiki / Asset integrity
The frame
Asset integrity
Asset integrity is keeping equipment fit to contain and carry its process safely through its whole life, by understanding how it degrades and inspecting so that degradation is caught before it becomes a failure. On fixed equipment the failure that matters most is loss of containment.
Integrity, and loss of containment
Reliability engineering keeps an asset running; integrity keeps it from leaking, rupturing or bursting. For pressure vessels, piping, tanks, exchangers and relief systems, the dominant risk is loss of primary containment, with consequences that can be safety, environmental and financial at once. Integrity management, the mechanical-integrity element of process safety, exists to keep that from happening, and risk-based inspection is how it is targeted.
The disciplines
| Risk-based inspection | RBI to API 580 and 581. Ranks equipment by risk and sets the inspection plan against it. |
|---|---|
| Damage mechanisms | API 571. The credible ways materials degrade in a given service, which is what RBI must screen for. |
| Thickness and condition monitoring | CMLs and TMLs, corrosion rates and remaining life from repeated measurement. |
| Fitness-for-service | API 579. Whether equipment with known damage is fit to keep operating, and for how long. |
| Integrity operating windows | API 584. The process limits that keep degradation within what the design assumed. |
| Inspection codes | API 510 for vessels, API 570 for piping, API 653 for tanks: the in-service inspection rules. |
The measures
| Risk | Probability of failure times consequence of failure. The currency of RBI and the thing being managed down. |
|---|---|
| Corrosion rate | Metal loss per year, short-term and long-term, from thickness history. Drives remaining life. |
| Remaining life | Time until a component reaches its minimum required thickness at the current rate. |
| Inspection effectiveness | How well an inspection actually detects the expected damage, graded A to E in API 581. |
Where OptimalIntegrity Studio™ fits
OptimalIntegrity Studio™ is the workbench for all of the above as one connected model: the equipment register and corrosion circuits, the screened damage mechanisms, the risk assessment, the inspection plan and the fitness-for-service checks live together, so a new thickness reading or a process change updates the risk and the plan rather than sitting in a separate file.