Pressure Vessel RBI – intro

RISK-BASED INSPECTION

Risk-Based Inspection (RBI) ensures you are performing the right inspections (procedure), on the right assets, in the right areas, at the right frequency. With thousands of assets to monitor, it can be challenging to properly prioritize inspection investments in efforts to reduce loss of containment risks to acceptable levels. Whether dealing with pressure vessels, pressure relief devices, piping segments, pipelines, check valves, or pump casings, loss of containment risks should be identified and mitigated before they happen. Risk-Based Inspection (RBI) can help these risks be proactively mitigated.

RBI is an approach used to assign risk to particular assets within a facility, and thus use that risk to prioritize and drive inspection strategies. In the oil and gas industry, it is guided by the American Petroleum Institute (API) RP 580, “The Recommended Practice for Risk-Based Inspection.”

PRESSURE RELEASE DEVICE (PRD) RISK-BASED INSPECTION (RBI)

Pressure Relief Devices (PRDs) are safety devices designed to protect pressurized vessels or systems during an overpressure event. Also known as pressure safety valves (PSVs), pressure relief valves (PRVs), safety relief devices (SRDs) and relief valves (RVs), PRDs serve as the last line of defense for pressure vessels, boilers, and other structures with pressurized containment. Due to their critical nature, it is vital to have a reliable inspection program – approved procedure in place to ensure availability of PRDs, in the case of overpressure events.

TANK RISK-BASED INSPECTION (RBI)

A tank RBI analysis will be performed for each atmospheric storage tank, utilizing with Tank RBI software tool. Design and process information, as well as inspection history, will be reviewed and input into the software. A corrosion assessment will be performed, risk will be calculated for the floor, shell courses and roof of the tank, and a report will be provided identifying the inspection plans for each tank. As a result of Tank RBI solution, facilities are able to achieve cost savings and reduced tank downtime through extended inspection intervals.

What can be defined using an Equipment Risk-Based Inspection?

Usefulness of RBI Inspection

The combination of both the assessments in an equipment risk-based inspection helps to define the following:

The type of future inspection (external/internal/on-stream) to be included in the inspection plan.
The appropriateness of non-destructive examination on the equipment.
The parts of equipment that ought to be examined in the future inspection.
The use of pressure testing if require
The use of repair techniques (whether it will be permanent or temporary)

Role of a Certified Inspector

A certified inspector is accountable to the equipment user to ensure the maintenance and QA/QC inspection programs in accordance with appropriate design codes and standards. He is to perform the visual inspections in order to determine all the factors which are required in both probability and consequence assessments.

Note:

Once an RBI assessment is conducted on a vessel, it should be revised after every vessel inspection, process change and repair work and whenever an unpredictable breakdown takes place.

References

American Petroleum Institute API 510; 3.1.65, 5.2

American Petroleum Institute API 580 Section 1.1.1

American Petroleum Institute API 581