Inspection effectiveness and risk in process industries

Conference · Sun Dec 01 04:00:00 EST 1996

OSTI ID:404245

Conley, M J; Tallin, A G ^[1]

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1. DNV, Houston, TX (United States)

Failures occasionally occur in refinery and petrochemical process equipment due to in-service damage such as internal corrosion, external corrosion, or stress corrosion cracking. Many of these failures should be preventable by detection of the damage prior to failure. However, selection of an inspection method for detection of damage has not always been based upon an evaluation of the required inspection effectiveness. Resources can be wasted by using an inspection method that is incapable of detecting damage, or is so unlikely to detect damage that it may be considered to be ineffective. Another waste of resources is excessive inspection, where the amount of inspection effort is not matched to the benefit. This paper outlines an approach to quantify the effectiveness of the complete inspection method, here defined as all of the elements that determine the mechanical integrity of an equipment item. This paper demonstrates the use of simple statistical tools or experimental techniques for estimating the effectiveness of an inspection method, and using this estimate in a risk evaluation. The approach is used to update the estimated severity of damage in process equipment after an inspection has been performed. The result of the analysis can be used in a risk assessment to estimate the risk associated with equipment failure before and after an inspection, thus providing a powerful tool to realistically set priorities for inspection planning.

• OSTI ID: 404245
• Report Number(s): CONF-960706--; ISBN 0-7918-1786-5
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
DECISION MAKING
IN-SERVICE INSPECTION
MAINTENANCE
NONDESTRUCTIVE TESTING
PETROCHEMICAL PLANTS
PETROLEUM REFINERIES
PROBABILISTIC ESTIMATION
RELIABILITY
RISK ASSESSMENT
SYSTEM FAILURE ANALYSIS