CONCEPT DEMONSTRATION
66Phillips 66Vessel Integrity Intelligence
← Vessel Registry

V-1135 — Vacuum Resid Drum V-1135

Delayed Coker · Vacuum Resid service · Installed Aug 31, 1991 (35 yrs in service)

High
Current Min. Thickness
0.688 in
t-min 0.928 in
Measured Corrosion Rate
9.29 mpy
ML-predicted: 8.84 mpy
Remaining Life
0.0 yrs
Next Inspection Due
Feb 20, 2027
Interval: 0.5 yrs (API 510)

UT Thickness Trend

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

Vessel Specification

MaterialSA-240-316L Stainless
Design CodeASME BPVC Section VIII, Div. 1
Joint Efficiency1.00
Design Pressure507 psig
Design Temperature568 °F
Operating Pressure440 psig
Operating Temperature347 °F
Diameter60 in
Nominal Thickness1.017 in
Corrosion Allowance0.0625 in
H2S / Chloride47 / 7 ppm
Flow Velocity1.4 ft/s
Process pH7.99
InsulatedNo

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
8.41 mpy
Predicted corrosion rate under these conditions (-0.88 mpy vs. current measured rate)
Implied Remaining Life
0.0 yrs
Implied Reinspection Interval
0.5 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 — High-Temperature Sulfidation

API 571 §4.2.11

Reaction of sulfur compounds with steel at high temperature (>500°F) in the absence of water; rate governed by sulfur content, temperature, alloy content.

Recommended inspection approach: UT thickness per Modified McConomy-curve risk ranking; RT/UT at known high-rate locations identified by process simulation.

Inspection History

UT thickness readings, most recent first

DateMethodCML CountAvg ThicknessMin CML Thickness
Aug 22, 2026UT Grid + RT40.6922 in0.6878 in
Oct 28, 2025UT Spot40.6970 in0.6951 in
May 31, 2024UT Spot40.7139 in0.7096 in
Jul 8, 2022UT Grid + RT40.7269 in0.7152 in
Feb 7, 2020UT Grid + RT40.7519 in0.7516 in
Jan 11, 2018UT Grid + RT40.7673 in0.7529 in
Jul 22, 2016UT Spot40.7832 in0.7765 in
Oct 3, 2014UT Grid + RT40.7988 in0.7815 in
Apr 23, 2013UT Grid + RT40.8138 in0.8072 in
Jun 7, 2011UT Grid + RT40.8335 in0.8298 in
Feb 12, 2009UT Spot40.8542 in0.8491 in
Apr 12, 2006UT Grid (API 572)40.8808 in0.8662 in
Oct 16, 2004UT Spot40.8953 in0.8770 in
Dec 27, 2001UT Grid (API 572)40.9212 in0.9064 in
Sep 20, 1999UT Spot40.9407 in0.9402 in
Apr 19, 1997UT Grid (API 572)40.9633 in0.9494 in
Sep 7, 1994UT Grid (API 572)40.9852 in0.9818 in
Feb 20, 1993UT Grid + RT41.0000 in0.9943 in