The same signed cards as the trainer above, in one list to read or print.
- How is the long-term corrosion rate worked out?
- Thickness loss between the first and the latest reading, divided by the years between them.API 510, the part on evaluating inspection data (corrosion rate and remaining life)
- How is the short-term corrosion rate worked out?
- Thickness loss between the two most recent readings, divided by the years between them.API 510, the part on evaluating inspection data (corrosion rate and remaining life)
- Long-term and short-term rates differ. Which one governs?
- The one the inspector judges best reflects current and expected process conditions. It is a judgement, not automatically the higher or lower.API 510, the part on evaluating inspection data (corrosion rate and remaining life)
- How is remaining life calculated?
- Remaining life = (actual thickness - required thickness) / corrosion rate.API 510, the part on evaluating inspection data (corrosion rate and remaining life)
- Readings 0.552 in. then 0.504 in. six years apart. Short-term rate?
- (0.552 - 0.504) / 6 = 0.008 in./yr.API 510, the part on evaluating inspection data (corrosion rate and remaining life)
- Actual 0.504 in., required 0.440 in., rate 0.008 in./yr. Remaining life?
- (0.504 - 0.440) / 0.008 = 0.064 / 0.008 = 8.0 years.API 510, the part on evaluating inspection data (corrosion rate and remaining life)
- A rate is given in mpy. How do you use it with thicknesses in inches?
- Divide by 1,000: 1 mpy is 0.001 in./yr. 5 mpy is 0.005 in./yr.API 510, the part on evaluating inspection data (corrosion rate and remaining life)
- A vessel has several CMLs. Which one sets the vessel's remaining life?
- The CML with the shortest remaining life, which is not always the thinnest or the fastest-corroding one.API 510, the part on evaluating inspection data (corrosion rate and remaining life)
- Actual 0.300 in., rate 0.010 in./yr. Projected thickness in 4 years?
- 0.300 - 4 x 0.010 = 0.260 in. Compare it with the required thickness before setting the next date.API 510, the part on evaluating inspection data (corrosion rate and remaining life)
- What is the default internal or on-stream inspection interval?
- Half the remaining life or 10 years, whichever is less.API 510, the part on inspection and testing intervals
- Remaining life 8 years. Default internal interval?
- Half of 8 is 4 years, which is under 10, so 4 years.API 510, the part on inspection and testing intervals
- Remaining life 30 years. Default internal interval?
- Half is 15 years, but the cap is 10, so 10 years.API 510, the part on inspection and testing intervals