CONCEPT DEMONSTRATION
66Phillips 66Vessel Integrity Intelligence
← Vessel Registry

V-1255 — Hot Hydrocarbon Vapor Drum V-1255

Crude Distillation Unit · Hot Hydrocarbon Vapor service · Installed Aug 23, 2020 (6 yrs in service)

Low-Medium
Current Min. Thickness
0.210 in
t-min 0.107 in
Measured Corrosion Rate
0.50 mpy
ML-predicted: 0.32 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. 2
Joint Efficiency1.00
Design Pressure60 psig
Design Temperature336 °F
Operating Pressure53 psig
Operating Temperature258 °F
Diameter71 in
Nominal Thickness0.228 in
Corrosion Allowance0.0938 in
H2S / Chloride45 / 245 ppm
Flow Velocity2.8 ft/s
Process pH6.82
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
0.10 mpy
Predicted corrosion rate under these conditions (-0.40 mpy vs. current measured rate)
Implied Remaining Life
60+ yrs
Implied Reinspection Interval
10.0 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 — Corrosion Under Insulation (CUI)

API 571 §4.3.5

Localized external corrosion beneath insulation where moisture is trapped, most severe in the 140–250°F operating band.

Recommended inspection approach: Insulation removal at high-risk locations (nozzles, low points), profile radiography, or guided-wave UT screening per API 570/RP 583.

Inspection History

UT thickness readings, most recent first

DateMethodCML CountAvg ThicknessMin CML Thickness
Aug 22, 2026UT Grid + RT60.2269 in0.2105 in
Oct 14, 2025UT Grid + RT60.2227 in0.2067 in
Apr 15, 2023UT Spot60.2249 in0.2149 in