Risk-Based Inspection for Polymers

A Risk-Based Inspection (RBI) work process has been developed for above-ground, fiberglass reinforced polymer (FRP) storage tanks.  The process complies with API's Recommended Practice 580 – Risk-Based Inspection which was developed for fixed equipment and piping in the hydrocarbon and chemical process industries. However the method has potential application to any class of industrial equipment such as FRP equipment.

Damage mechanism documentation was developed for five chemical / tank construction combinations.  A damage mechanism is any deterioration that causes equipment or process unit failure to meet specified performance targets such as Safety, Health and Environmental (S/H/E) performance, production capacity, and product quality.  The damage mechanism documentation guides the cross functional RBI team, typically consisting of a facilitator, plant operators, turnaround planners, plant maintenance and subject matter experts (SMEs). If damage mechanism documentation is not available, the failure scenarios can be developed by the team through plant history records, personnel experience and input from SMEs.

The RBI work process includes a benefit-cost analysis which compares the economic benefit of mitigation with the cost of the selected mitigating actions and reports mitigation of S/H/E risk. This RBI work process allows reliability monitoring while delivering a task-focused, cost effective inspection and maintenance plan for an FRP storage tank.