by austenite.org

The corrosion tool that thinks like a metallurgist
and speaks in probabilities.

Microstructure-aware, probabilistic prediction of pitting, chloride-SCC and sour cracking — plus cost-aware CRA selection. Runs entirely in your browser.

composition → PRENσ-phase couplingCPT + credible interval Cl-SCC · sour SSCcost-aware selectionCCUS / H₂
PitCast · pitcast.austenite.org · screening estimate — not a substitute for qualified engineering

Material

Service conditions

Advanced — thermal / weld history (σ-phase)

e.g. 850 °C for 4 h precipitates σ-phase and sharply lowers CPT.

Enter conditions →

Service conditions

Recommends the cheapest grade whose overall risk clears the threshold — avoiding over-specification.

Set a service →
Side-by-side evaluation of up to 5 candidate grades against one set of service conditions. Best / worst values per metric highlighted; cheapest grade that clears the risk threshold marked. Industry workflow: shortlist for FEED material-selection memos.

Candidate grades (up to 5)

Service conditions (shared)

Each grade is run through PitCast.assess() with the same service. Green cell = best in that column, red cell = worst. The ★ row is the cheapest grade that clears the threshold.

Pick grades and conditions →

All real measured records from the cited open database (Nyby et al., Scientific Data 2021, CC BY 4.0). Search by alloy or UNS, filter by metric, and click Assess → to load any record's composition into the tool.

Probabilistic Material Selection Diagram — sweeps the validated engine across a service window and overlays the safe operating limit on the ISO 15156-3 boundary. The physics-vs-code diff (right) is the part no off-the-shelf calculator gives you.

Alloy

Diagram

Operating point

Pick an alloy and a map →
Sweet CO₂ corrosion of carbon steel — five canonical models on one operating point · de Waard 1975/1995 · NORSOK M-506:2017 · NESC · Multicorp · cited

Environment preset

Operating point

Corrosion allowance

Set an operating point →
Cathodic-protection criteria (AMPP SP0169) + AC-corrosion screening (ISO 18086) for buried carbon-steel pipe · holiday spread-resistance model · cited

AC interference (at a coating holiday)

CP criteria (mV vs Cu/CuSO₄)

Instant-off (IR-free) is the value the −850 mV criterion is judged on; the ON potential includes IR drop and can falsely "pass".

Sacrificial anode sizing (DNV-RP-B401 / NACE SP0387)

Galvanic couple (ASTM G82 / MIL-STD-889)

Groundbed (Dwight / Sunde — NACE SP0169 / IEEE 81)

Enter AC + CP data →
Pipeline integrity — ASME B31G / Modified B31G corroded-pipe fitness-for-service + general remaining-life. PE-grade screening for axial external metal-loss defects (ILI / inspection patches).

Pipe geometry

External metal-loss defect

Remaining-life (uniform CR)

CUI risk (API 583 / NACE SP0198)

MIC risk (NACE TM0194 / TM0212 / SP0775)

HIC / SOHIC risk (NACE MR0103 / TM0284 / ISO 15156-2)

HIC needs free water + pH₂S > 0.34 kPa (ISO 15156). SOHIC adds tensile-stress amplification — dominant above ~250 HV.

RBI screening (API RP 581 — 5×5 matrix)

Reuses pipe geometry (tnom, tmin) from above. Screening only — full API 581 uses detailed damage-factor tables.

Set pipe geometry →
In-Line Inspection (ILI) batch screen. Upload a CSV of corrosion defects from your ILI vendor (e.g. ROSEN, Baker Hughes, NDT Global), apply pipeline-level geometry + grade + MAOP defaults, and the engine runs ASME B31G / Modified-B31G on every defect, returns a sortable color-coded grid (PASS / MONITOR / REPAIR / IMMEDIATE), with summary stats and severity histogram. Industry workflow: ILI run → defect triage → repair-priority list.

Pipeline-level defaults

Defect CSV

Required columns: id, length_mm, depth_mm. Optional: chainage_m, clock_pos, width_mm, defect_type. Download sample CSV (15 defects, real-shape distribution)

Verdict bands per ASME B31G §3.6 + Kiefner 1989: PASS (Psafe ≥ MAOP, d/t < 50%) · MONITOR (50–80% wall loss, frequent re-insp.) · REPAIR (Psafe < MAOP) · IMMEDIATE (≥80% wall, replace before re-pressurise).

Upload or paste an ILI defect CSV →

How it works

Thirteen cited engines across four engineering workflows — every output traceable to a primary standard (ASME · NACE · DNV · ISO · API · ASTM · MIL-STD). 5,500+ in-Chrome assertions verify known-answer worked examples, monotonicity invariants, and boundary gates against published values.

① CRA selection & pitting

Composition → PRENN16 → CPT (Nyby 2021 LOO-calibrated, MAE 6.6 °C) → P(pit) with credible interval. σ-phase and sensitization from thermal/weld history; effective-local-PREN coupling degrades CPT — the microstructure-aware link no off-the-shelf tool carries. Cl-SCC + sour SSC envelopes per ISO 15156-3. Multi-grade compare; cost-aware "cheapest grade that clears." Assess · Select · Compare · Selection map · Browse data tabs

② Pipeline integrity (FFS)

ASME B31G / Modified B31G (Kiefner & Vieth 1989 — RSTRENG-derived 0.85 dL) corroded-pipe fitness for service with the Folias bulging factor. Remaining-life per API 570 / 510 conventions. ILI batch upload: paste a vendor CSV (ROSEN / Baker Hughes / NDT Global), get a sorted color-coded grid of PASS / MONITOR / REPAIR / IMMEDIATE per defect. CUI risk per API 583 + NACE SP0198 with ASTM C871 leachable-chloride amplifier for SS ext-CSCC. RBI 5×5 screen per API RP 581. Integrity · ILI batch tabs

③ CP, coatings & galvanic

Sacrificial anode sizing per DNV-RP-B401 §6/§7/§10 across 31 environments (T / depth / salinity / O₂ / ρ context), 15 coating systems, 11 NACE SP0387 anode alloys. AC corrosion (ISO 18086 holiday model) + AMPP SP0169 CP-criteria check. Galvanic couple from a 68-alloy ASTM G82 / MIL-STD-889C series with mixed-potential Tafel I_corr (ASTM G102) returning actual mm/yr penetration on the anode. Groundbed resistance per Dwight 1936 (vertical / horizontal) + Sunde 1949 (n-rod). CP / AC tab

④ Damage-mechanism screens

CO₂ corrosion: 5-model comparator (de Waard 1975 + 1995, NORSOK M-506:2017, Nesic Multicorp, Multicorp-FreeCorp) plus API RP 14E erosional-velocity check. HIC / SOHIC per NACE MR0103-2018 + TM0284-2016 + ISO 15156-2 (0.34 kPa pH₂S gate) with explicit mitigation hierarchy. MIC families (SRB / APB / IRB / SOB) per NACE TM0194 / TM0212 / SP0775. Sour-service envelope per NACE MR0175 / ISO 15156 with H₂S-CO₂ regime mapping. Energy-transition coverage: scCO₂ + H₂ embrittlement. CO₂ · Integrity tabs

Outputs are downloadable: print-to-PDF (clean single-card layout per tab), per-tab XLSX (multi-sheet: Inputs / Results / Citations), or CSV. Pure calculation + cited reference — no stamp ceremony.

About & honest limits

PitCast began as the CRA-selection layer of a validated Python research package and grew into a pipeline / materials / corrosion-engineering screening console — the kind a working PE or AMPP Corrosion Specialist keeps open in a browser tab next to AutoCAD, Caesar II, and the spec book. Every engine is in-browser vanilla JS; no server, no account, no telemetry. Every dataset entry is either cited to a primary standard or flagged as screening.

Validation & accuracy

5,500+
in-Chrome assertionsacross 13 capabilities
100+
cited primary sourcesASME · NACE · DNV · ISO · API · ASTM
6.6 °C
CPT LOO mean abs. errorNyby 2021, n=51, RMSE 8.5 °C
250
cited material options8 industry-grade dropdowns

Each capability is validated against its standard's worked example where one exists: ASME B31G Appendix B Ex 1 (54.3 / 55.6 bar Psafe); NACE SP0169 Appendix-A groundbed (13.72 Ω); DNV-RP-B401 1-km × 12-in offshore pipeline (4,754 kg Al-Zn-In); LaQue marine 316L bolt in CS flange (~1.16 mm/yr CR); Nyby et al. 2021 Scientific Data 8, 58 (CC BY 4.0) LOO calibration on n=51 G48 records. Monotonicity invariants enforced everywhere (deeper defect ↓ Psafe, more chloride ↑ pitting, more cathode area ↑ galvanic rate, higher pH₂S ↑ HIC, etc.).

What each engine cites

B31G FFS: ASME B31G-2012 §2-3 · Kiefner & Vieth 1989 (Battelle PR-3-805) · Folias 1965 Int J Fract Mech 1, 104 · API 5L · API 570/510.

Anode sizing: DNV-RP-B401 §6/§7/§10 (Tables 7-1, 10-1, 10-2) · NACE SP0387 (offshore cast anodes) · NACE SP0169 (buried steel) · NACE SP0572 (Mg anodes) · NACE SP0490 / SP0492 / SP0212 + ISO 21809 + AWS C2.18 (FBE / 3LPE / TSA).

CUI: API RP 583 §4.3-4.4/§5 · NACE SP0198-2017 · API RP 581 (intervals) · ASTM C871 leachable Cl · ASTM C449/C547/C552/C591/C610/C612/C1126/C1728/C1136 · ISO 9223.

Galvanic: ASTM G82-98(2014) · ASTM G102-89(2015) · MIL-STD-889C · NACE TM0394 · LaQue 1975 Marine Corrosion Ch.6 · Stansbury & Buchanan 2000 Ch.4 (mixed-potential) · Trethewey & Chamberlain 1995 Tab 3.4 · ISO 12473.

Groundbed: Dwight 1936 AIEE Trans 55, 1319 · Sunde 1949 (Van Nostrand) · NACE SP0169 §6.5 · IEEE Std 81.

HIC / SOHIC: NACE MR0103-2018 · NACE TM0284-2016 (CLR ≤ 15% / CTR ≤ 5% / CSR ≤ 2%) · ISO 15156-2 §A.2/§B · API RP 571 §5.

RBI: API RP 581 (3rd ed., 2016) Parts 1-3 · API RP 580 · API 510 / 570 interval caps.

MIC: NACE TM0194 (planktonic) · NACE TM0212 (sessile/pipeline) · NACE SP0775 (coupons) · NACE SP0106 §6.

CRA / CPT: Nyby et al. 2021 Sci Data 8, 58 (LOO calibration n=51) · ASTM G48 (6% FeCl₃) · ISO 15156-3 · NACE MR0175 · WRC-1992 ferrite diagram.

CO₂ corrosion: de Waard & Milliams 1975/1995 · NORSOK M-506:2017 · Nesic Multicorp · Crolet & Bonis 1983 (in-situ pH) · API RP 14E (erosional velocity).

CP / AC: AMPP SP0169 · ISO 18086 (AC-corrosion holiday spread-resistance model).

Cited measured anchors

Independent literature data points the models are checked against — each row links to its primary source.

⚠ Screening / research-grade. The CRA-selection CPT correlation is statistically calibrated (Nyby 2021 LOO MAE 6.6 °C — close to the intrinsic lab-to-lab scatter of CPT measurement). Other engines reproduce their cited standard's worked examples within ~2% but are flagged as screening where vendor-batch polarisation data, full-table damage factors (e.g. API 581 detailed DFM tables), or site-specific environmental measurements would normally be used in detailed design. Not a substitute for qualified materials engineering, standards compliance, or testing. Do not use unsupervised for design.

© austenite.org · PitCast — corrosion & integrity console for metallurgists, FEED engineers, AMPP corrosion specialists, and PE pipeline-integrity engineers.