Inspection and Maintenance Flashcards
7 cards from real API practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Inspection and Maintenance flashcards as text
Under API 570, which condition would classify a piping circuit as requiring an 'on-stream' inspection rather than an internal inspection?
Answer: Piping that cannot be isolated and cleaned for internal access
When piping cannot be safely isolated, depressured, and cleaned to allow internal access, on-stream inspection methods such as UT thickness scanning are used as an alternative.
In the context of API inspection, what is a 'corrosion circuit' or 'inspection circuit'?
Answer: A group of piping or equipment sections with similar corrosion characteristics and rates
A corrosion circuit is a defined segment of piping or equipment expected to corrode at similar rates due to similar process conditions, used to rationalize inspection point selection.
Which API standard provides guidance on risk-based inspection methodology for pressure vessels and piping?
Answer: API 580
API 580 provides the framework and principles for implementing Risk-Based Inspection (RBI) programs for pressure-containing equipment in the refining and petrochemical industries.
What is the significance of the 'T-min' value in API inspection standards?
Answer: The minimum allowable thickness below which equipment must be repaired or retired
T-min is the minimum allowable thickness calculated to safely contain the operating pressure, and equipment must be repaired or taken out of service when measurements fall at or below this value.
Which inspection technique is best suited for detecting laminations and internal flaws in pressure vessel plate without removing the vessel from service?
Answer: Straight-beam Ultrasonic Testing (UT)
Straight-beam UT sends sound waves perpendicular to the surface and can detect internal laminations and subsurface flaws without requiring vessel shutdown or surface preparation for ferrous detection.
According to API 653, how is the maximum fill height of a repaired storage tank typically determined after bottom repairs?
Answer: Through engineering calculations considering new floor condition, shell condition, and foundation
Maximum fill height after repairs is determined through engineering calculations that account for the repaired floor's condition, shell integrity, and the foundation's load-bearing capacity.
What is the primary purpose of cathodic protection systems on buried or submerged piping per API inspection standards?
Answer: To apply an electrical current that counteracts electrochemical corrosion
Cathodic protection applies a protective electrical current (or uses sacrificial anodes) to counteract the electrochemical reactions that cause corrosion on buried or submerged metal surfaces.