29/10/2026
You have an ultrasonic gauge reading on a Class 2 piping line. Which maximum inspection intervals do you sign off on? ⏱️👇
Hello Professionals,
Calculating Remaining Life under API 570 is straightforward, but candidates often lose marks under exam pressure by applying the Half-Life value across both inspections and overlooking the Class 2 limits in Section 6 (Table 1).
CIRCUIT DATA:
• Service: Class 2 Process Piping
• Measured Wall Thickness (t_actual) = 8.5 mm
• Required Thickness (t_req) = 4.5 mm
• Corrosion Rate (CR) = 0.25 mm/year
• Condition: No RBI assessment
What are the maximum permitted intervals for:
Thickness Measurement (UT) / External Visual Inspection?
[A] UT: 8 yrs / Ext: 8 yrs
[B] UT: 5 yrs / Ext: 5 yrs
[C] UT: 16 yrs / Ext: 5 yrs
[D] UT: 8 yrs / Ext: 5 yrs
Drop [A], [B], [C], or [D] in the comments with your reasoning! We will break down the exact step-by-step code clauses in the replies.
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