CONCEPT DEMONSTRATION
66Phillips 66Vessel Integrity Intelligence
← Vessel Registry

V-1274 — Vacuum Gas Oil Column V-1274

Fluid Catalytic Cracker · Vacuum Gas Oil service · Installed Aug 26, 2010 (16 yrs in service)

Low-Medium
Current Min. Thickness
2.259 in
t-min 2.110 in
Measured Corrosion Rate
1.69 mpy
ML-predicted: 3.21 mpy
Remaining Life
60+ yrs
Next Inspection Due
Aug 19, 2036
Interval: 10.0 yrs (API 510)

UT Thickness Trend

Minimum CML reading per inspection vs. ASME Sec. VIII t-min

Vessel Specification

MaterialSA-516-70 Carbon Steel
Design CodeASME BPVC Section VIII, Div. 1
Joint Efficiency1.00
Design Pressure479 psig
Design Temperature706 °F
Operating Pressure374 psig
Operating Temperature590 °F
Diameter141 in
Nominal Thickness2.298 in
Corrosion Allowance0.1250 in
H2S / Chloride30 / 96 ppm
Flow Velocity11.0 ft/s
Process pH6.49
InsulatedYes

Corrosion & Remaining-Life What-If

Adjust operating conditions to see the live model-predicted corrosion rate and implied remaining life

Live Prediction — What-If Model
9.21 mpy
Predicted corrosion rate under these conditions (+7.52 mpy vs. current measured rate)
Implied Remaining Life
16.2 yrs
Implied Reinspection Interval
8.1 yrs

What-if model: standardized Ridge regression, R² 0.56 on held-out fleet data (3.25 mpy MAE). Runs entirely client-side for instant feedback — see Model Insights for the full fleet-scale ensemble model used for official predictions.

Governing Damage Mechanism — Naphthenic Acid Corrosion

API 571 §4.2.10

Aggressive, velocity-assisted corrosion in high-TAN crude fractions, most severe 450–750°F; low-alloy/carbon steel is far more susceptible than Mo-bearing or 316 SS.

Recommended inspection approach: UT thickness at high-velocity/turbulent locations; feed TAN monitoring; consider alloy upgrade per API 571 guidance.

Inspection History

UT thickness readings, most recent first

DateMethodCML CountAvg ThicknessMin CML Thickness
Aug 22, 2026UT Grid (API 572)42.2718 in2.2587 in
Apr 24, 2025UT Grid (API 572)42.2731 in2.2730 in
Jan 17, 2023UT Grid + RT42.2778 in2.2757 in
Jun 15, 2020UT Grid (API 572)42.2857 in2.2842 in
Dec 25, 2018UT Spot42.2846 in2.2675 in
Mar 22, 2017UT Grid + RT42.2856 in2.2702 in
Nov 25, 2014UT Spot42.2914 in2.2887 in
Jun 23, 2013UT Spot42.2961 in2.2844 in