The neqsim.process.materials package provides a process-wide review layer for material selection, corrosion and degradation screening, integrity checks, and lifetime considerations. It orchestrates the existing point calculators in neqsim.process.corrosion and mechanical-design utilities into one auditable report per equipment or line-list item.

The main use case is to support and challenge projects or producing assets using normalized data from STID, piping classes, equipment registers, inspection databases, material certificates, and process simulations. The examples below are synthetic and must not be replaced with real asset names, document IDs, or internal database rows in public documentation.

What It Does

Capability Implementation
CO2 corrosion rate NorsokM506CorrosionRate
Material selection and corrosion allowance NorsokM001MaterialSelection
Sour service SourServiceAssessment
Chloride SCC ChlorideSCCAssessment
Dissolved oxygen corrosion and pitting OxygenCorrosionAssessment
Dense phase CO2 impurity and free-water risk DensePhaseCO2Corrosion
Hydrogen embrittlement and HTHA HydrogenMaterialAssessment, NelsonCurveAssessment
Ammonia service compatibility AmmoniaCompatibility
Corrosion under insulation CUIRiskAssessment
Erosion-corrosion, MIC, galvanic corrosion, fatigue/FIV Screening rules in MaterialsReviewEngine
Remaining life Wall-thickness and corrosion-rate screening in IntegrityLifeAssessment

Core Classes

Class Purpose
MaterialsReviewEngine Runs the review from normalized input or a ProcessSystem plus material register
MaterialsReviewInput Holds project metadata, design life, and review items
MaterialReviewItem One tag, line, vessel, exchanger, or other asset to assess
MaterialServiceEnvelope Flexible service-condition map for process and integrity data
StidMaterialsDataSource Normalized STID/technical database JSON bridge
MaterialReviewResult Item-level findings, mechanisms, recommendation, and life result
MaterialsReviewReport Process-wide JSON report

STID and Technical Database Workflow

NeqSim does not connect directly to STID from the Java core. Retrieval, OCR, and document parsing remain in devtools and skills. The Java engine consumes normalized JSON, which keeps the core deterministic and testable.

Typical workflow:

  1. Extract or retrieve STID, line-list, material-class, inspection, and certificate data.
  2. Normalize rows into materialsRegister, lineList, equipment, inspectionData, or materialCertificates arrays.
  3. Include source references such as document names, row IDs, tag IDs, or database keys.
  4. Optionally provide processJson so NeqSim can calculate pressure, temperature, and composition before the review.
  5. Run MaterialsReviewEngine directly or the MCP tool runMaterialsReview.

Records with the same tag are merged, so material data and inspection data can come from different extracts.

Before committing review inputs or outputs to an open repository, strip or pseudonymize source document names, tag numbers, database IDs, asset names, and sensitive inspection comments. The engine echoes item tags, source references, metadata, and service values in its JSON report for traceability.

JSON Input Shape

{
  "projectName": "Synthetic materials review",
  "designLifeYears": 25,
  "materialsRegister": [
    {
      "tag": "DEMO-LINE-001",
      "equipmentType": "Pipeline",
      "existingMaterial": "Carbon Steel API 5L X65",
      "sourceReferences": ["synthetic STID line-list row 1"],
      "service": {
        "temperature_C": 85.0,
        "pressure_bara": 95.0,
        "co2_mole_fraction": 0.04,
        "h2s_mole_fraction": 0.0008,
        "free_water": true,
        "chloride_mg_per_l": 55000.0,
        "pH": 5.2,
        "flow_velocity_m_per_s": 7.5,
        "nominal_wall_thickness_mm": 18.0,
        "current_wall_thickness_mm": 15.2,
        "minimum_required_thickness_mm": 11.0
      }
    }
  ]
}

Java Usage

MaterialsReviewInput input = new MaterialsReviewInput();
MaterialServiceEnvelope service = new MaterialServiceEnvelope()
    .set("temperature_C", 85.0)
    .set("pressure_bara", 95.0)
    .set("co2_mole_fraction", 0.04)
    .set("h2s_mole_fraction", 0.0008)
    .set("free_water", Boolean.TRUE)
    .set("chloride_mg_per_l", 55000.0);

input.addItem(new MaterialReviewItem()
    .setTag("DEMO-LINE-001")
    .setEquipmentType("Pipeline")
    .setExistingMaterial("Carbon Steel API 5L X65")
    .setServiceEnvelope(service));

MaterialsReviewReport report = new MaterialsReviewEngine().evaluate(input);
System.out.println(report.toJson());

This pattern is covered by MaterialsReviewEngineTest.

Process Simulation Overlay

When a ProcessSystem is supplied, the engine extracts each unit operation’s temperature, pressure, and selected component mole fractions. The material register is then merged by tag.

MaterialsReviewReport report = new MaterialsReviewEngine().evaluate(processSystem, materialRegister);

Use this when the process model is the source of operating conditions and STID is the source of material, wall-thickness, coating, insulation, and inspection data.

MCP Tool

The MCP server exposes the same workflow as runMaterialsReview.

{
  "materialsReviewJson": "{\"projectName\":\"Synthetic materials review\",\"materialsRegister\":[...]}"
}

The MCP output includes:

Output Interpretation

The report is intended for screening, challenge, and decision-support workflows. A FAIL means at least one mechanism or integrity-life check needs engineering attention. A PASS_WITH_WARNINGS means the material may be acceptable, but the review found inspection, operating-envelope, data-quality, or mitigation actions to close.

Final material selection, corrosion management strategy, and integrity decisions still require discipline engineer review, project technical requirements, and verified STID/source data.