--- name: neqsim-equipment-cost-estimation version: "1.0.0" description: "Equipment and process CAPEX estimation — Turton/Peters/Ulrich/Seider correlations, CEPCI escalation, material/pressure factors, bare-module to grass-roots, AACE class 1-5, location factors, currency conversion, CostEstimateResult reconciliation, and mechanical-design-driven topsides/SURF/well rollups. USE WHEN: a task requires a +30%/-30% Class-3/4 estimate for equipment, a process flowsheet, topsides, SURF, wells, or reservoir-to-market CAPEX. Anchors on CostEstimationCalculator and ProcessCostEstimate." last_verified: "2026-06-28" requires: java_packages: [neqsim.process.costestimation] --- # NeqSim Equipment Cost Estimation Skill Class-3/4 (AACE 18R-97) order-of-magnitude to study estimates for individual process equipment and early process/facility CAPEX rollups - the bridge between sized equipment and a project economics model. Wraps Turton (5e), Peters–Timmerhaus, Ulrich, and Seider correlations with CEPCI escalation, material factors, pressure factors, and Lang/Hand factors. The preferred NeqSim path is mechanical-design driven: call each unit's `initMechanicalDesign()`, `calcDesign()`, then `getMechanicalDesign().getCostEstimate().calculateCostEstimate()` or let `ProcessCostEstimate.calculateAllCosts()` do that rollup for a full flowsheet. ## When to Use - Quickly cost a sized vessel, column, HX, pump, compressor, filter, reactor, mixer, splitter, or manifold - Build a **bare-module** → **total-module** → **grass-roots** stackup - Apply CEPCI to escalate published correlations to current year - Compare alternatives (e.g. centrifugal vs reciprocating compressor) - Produce a scope-safe `CostEstimateResult` for equipment, process, topsides, SURF, subsea, well, or field-development estimates - Reconcile located process totals against located equipment rows while retaining base equipment costs - Feed equipment cost into NPV / IRR via [`neqsim-field-economics`](../neqsim-field-economics/SKILL.md) > For project-level economics, asset valuation, or fiscal regimes, use > [`neqsim-field-economics`](../neqsim-field-economics/SKILL.md). This skill is > the CAPEX basis skill that feeds those economics workflows. ## AACE Cost Estimate Classes | Class | Maturity | Accuracy | Method | | ----- | ------------- | ------------- | ----------------------------- | | 5 | Concept | −50% / +100% | Capacity-factor (six-tenths) | | 4 | Pre-FEED | −30% / +50% | Equipment-factored (this skill) | | 3 | FEED | −20% / +30% | Sized equipment + bulk MTOs | | 2 | Detailed | −15% / +20% | Detailed quantity takeoff | | 1 | Final | −10% / +15% | Vendor quotes | ## Correlation Validity Range (READ THIS FIRST) The Turton correlations are fitted over a stated capacity range. NeqSim does **not** refuse a capacity outside that range — it evaluates the polynomial anyway and returns a number that looks ordinary. Observed case: a 239 MW compression duty evaluated against a correlation valid to 3000 kW returned about 6 MUSD — roughly **80× too low**, with no warning. In the same study the weight-based `calcColumnShellCost` returned ~500 MUSD for a single contactor because it feeds a shell **weight** into coefficients fitted on **volume**. The two errors partly cancelled, and the study total was wrong by a factor of three while appearing internally consistent. Rules: 1. **Check the range before calling.** Compressors 450–3000 kW; pumps 1–300 kW; vessels by volume. 2. **Oversized duties are parallel units, not extrapolation.** Split the duty into `ceil(capacity / max_capacity)` units at `capacity / n` each and cost each inside the range. `CostEstimationCalculator` now does this internally for compressors and pumps. 3. **Never use the weight-based vessel/column methods.** `calcVerticalVesselCost`, `calcHorizontalVesselCost` and `calcColumnShellCost` are deprecated: their capacity basis is volume, not shell weight. Use `calcVerticalVesselCostByVolume` and pass the actual volume. 4. **Anchor the total.** Cross-check specific CAPEX against a published comparable for the concept type before believing the sum. A result outside the expected band by more than a factor of 1.5 is a bug until proven otherwise. ## Pattern 1 — Bare-module Cost for a Vessel ```java import neqsim.process.costestimation.CostEstimationCalculator; CostEstimationCalculator cost = new CostEstimationCalculator(); cost.setCurrentCepci(CostEstimationCalculator.CEPCI_2025); // 840 cost.setMaterialOfConstruction("SS316"); // sets Fm = 2.1 cost.setLocationByRegion("Norway"); // location factor double shellWeight_kg = 8500.0; // from mechanical design double designP_barg = 110.0; double Cp = cost.calcVerticalVesselCost(shellWeight_kg); double Cbm = cost.calcBareModuleCost(Cp, designP_barg); // applies Fp & Fm double Ctm = cost.calcTotalModuleCost(Cbm); // + contingency + fees double Cgr = cost.calcGrassRootsCost(Ctm); // + auxiliary facilities ``` ## Pattern 2 — End-to-end via `calculateCostEstimate` ```java cost.calculateCostEstimate( Cp, // purchased equipment cost designP_barg, // for Fp shellWeight_kg, // for installation man-hours "vertical_vessel" // equipment category ); String json = cost.toJson(); // structured output for results.json ``` ## Pattern 3 — Volume-Based Vessel Cost For screening work, use the volume-based methods when the mechanical design knows vessel diameter and length but the shell weight is not yet reliable. These are now the preferred basis for separator, absorber, column, filter, and reactor vessel screening. ```java double vesselVolume_m3 = Math.PI * diameter_m * diameter_m / 4.0 * tanTanLength_m; double verticalCp = cost.calcVerticalVesselCostByVolume(vesselVolume_m3); double horizontalCp = cost.calcHorizontalVesselCostByVolume(vesselVolume_m3); ``` Keep the legacy `calcVerticalVesselCost(weight_kg)` and `calcHorizontalVesselCost(weight_kg)` methods for cases where the mechanical design has already produced a defensible shell weight. ## Pattern 4 — CEPCI Escalation ``` C_today = C_published × CEPCI_today / CEPCI_published ``` Built-in indices: `CEPCI_2019` (607.5) through `CEPCI_2025` (840). Escalate any literature correlation that's published with a base year. ## Pattern 5 — Equipment-Specific Methods | Equipment | Method | Sizing input | | ------------------------ | -------------------------------------- | --------------------- | | Vertical pressure vessel | `calcVerticalVesselCost(weight_kg)` | shell weight | | Horizontal vessel | `calcHorizontalVesselCost(weight_kg)` | shell weight | | Vertical vessel screening | `calcVerticalVesselCostByVolume(volume_m3)` | vessel volume | | Horizontal vessel screening | `calcHorizontalVesselCostByVolume(volume_m3)` | vessel volume | | Distillation column | `calcColumnShellCost(weight_kg)` + `calcSieveTraysCost(D, N)` | weight + diameter + tray count | | Shell-tube HX | `calcShellTubeHeatExchangerCost(area_m2)` | area | | Plate HX | `calcPlateHeatExchangerCost(area_m2)` | area | | Air cooler | `calcAirCoolerCost(area_m2)` | bare-tube area | | Centrifugal pump | `calcCentrifugalPumpCost(power_kW)` | shaft power | | Centrifugal compressor | `calcCentrifugalCompressorCost(power_kW)` | shaft power | | Reciprocating compressor | `calcReciprocatingCompressorCost(power_kW)` | shaft power | | Piping | `calcPipingCost(D_m, L_m, schedule)` | diameter, length | | Control valve | `calcControlValveCost(Cv)` | Cv | ## Pattern 6 — Mechanical-Design Estimator Wiring Equipment-specific mechanical designs own their estimator selection. This is what makes full-process rollups work: `ProcessCostEstimate` does not need to know every unit's detailed sizing correlation; it asks the unit for its mechanical design and cost estimate. ```java unit.initMechanicalDesign(); MechanicalDesign design = unit.getMechanicalDesign(); design.calcDesign(); design.getCostEstimate().calculateCostEstimate(); double grassRootsCostUSD = design.getCostEstimate().getGrassRootsCost(); ``` Current topside coverage includes specialized mechanical-design/cost paths for separators, scrubbers, columns, absorbers, adsorbers, mercury removal, pumps, compressors, expanders, ejectors, heat exchangers, BAHX units, tanks, pipelines, valves, mixers, splitters, filters, reactors, and manifolds. Header-like units such as mixers and splitters should calculate dry weight during `calcDesign()`; filter/reactor/manifold estimators reuse the mechanical design outputs instead of duplicating sizing logic. ## Pattern 7 — Material and Pressure Factors (Turton) ```java double Fp = CostEstimationCalculator.getPressureFactor(designP_barg); // ~1.0–3.0 // Fm constants: FM_CARBON_STEEL=1.0, FM_SS304=1.8, FM_SS316=2.1, // FM_SS316L=2.3, FM_MONEL=3.2, FM_HASTELLOY_C=3.8, FM_TITANIUM=4.5 ``` ## Pattern 8 — Stackup Convention ``` Cp = purchased equipment, FOB factory (input) Cbm = Cp × (B1 + B2 × Fm × Fp) bare module Ctm = Cbm × 1.18 + contingency 15% + fees 3% Cgr = Ctm × 1.30 + 30% auxiliary (utilities, storage, OSBL) ``` ## Pattern 9 — Cost Estimate for a Whole Process ```java ProcessCostEstimate processCost = new ProcessCostEstimate(process); processCost.calculateAllCosts(); double totalCgr = processCost.getTotalGrassRootsCost(); ``` Use this rollup for reservoir-to-market screening once the flowsheet contains unit operations for the major equipment. It initializes each unit's mechanical design, runs `calcDesign()`, calls the attached estimator, and aggregates the result by equipment category. ## Pattern 10 — Result Schema and Reconciliation Use `CostEstimateResult` when handing estimates to reports, agents, or downstream economics. The map names encode whether rows are additive, summary totals, or non-cost quantities: | Map | Meaning | Reconciliation Rule | | --- | ------- | ------------------- | | `capitalCosts_USD` | Additive direct capital-cost lines | Sum only inside the same scope | | `capitalCostBreakdown_USD` | Supplementary detail behind a capital line | Do not add to the parent line | | `capitalCostSummary_USD` | Capital subtotals/totals | Show as totals; do not re-sum | | `projectCosts_USD` | Additive project-cost lines | Sum only inside the matching project scope | | `projectCostSummary_USD` | Project subtotals/totals | Show as totals; do not re-sum | | `quantityBasis` | Non-cost quantities with units | Never mix into USD totals | | `weightBasis_kg` and `materialTakeOff` | Physical basis and MTO traceability | Keep separate unless building a controlled MTO rollup | Examples of intended placement: - Unit estimators: `purchasedEquipmentCost` in `capitalCosts_USD`; `bareModuleCost`, `totalModuleCost`, and `grassRootsCost` in `capitalCostSummary_USD`; `installationManHours` in `quantityBasis`. - `ProcessCostEstimate`: process PEC/BMC/TMC/grass-roots in `capitalCostSummary_USD`; `totalProjectCost` in `projectCostSummary_USD`; `totalInstallationManHours` in `quantityBasis`. - Topsides facilities: direct field cost and excluded non-topsides scope in `capitalCostSummary_USD`; `totalTopsidesCapex` in `projectCostSummary_USD`; module detail in `capitalCostBreakdown_USD`. - SURF/development: `totalSURF` and `totalDevelopment` in `capitalCostSummary_USD`; vessel days in `quantityBasis`. `ProcessCostEstimate.toJson()` reports equipment rows with location-adjusted costs in the standard `*_USD` fields, because those rows must reconcile with the process totals and `costByEquipmentType_USD`. Base, unlocated rows remain under `basePurchasedEquipmentCost_USD`, `baseBareModuleCost_USD`, `baseTotalModuleCost_USD`, and `baseGrassRootsCost_USD`, with `locationFactor` shown explicitly. ## Common Mistakes | Mistake | Fix | | ------------------------------------------------- | ------------------------------------------------------------------- | | Using outdated CEPCI | Always set `setCurrentCepci(CEPCI_)` before calculating | | Hardcoding Fm = 1 | Pick from `FM_*` constants based on actual material of construction | | Missing pressure factor at high P | Use `getPressureFactor(P)` — silently × the cost at HP/HIPPS service | | Reporting Cp as "installed cost" | Cp is FOB only; installed = at minimum Cbm | | Mixing currencies | Use `setCurrency(code, rate)` then read all costs through `convertFromUSD/convertToUSD` | | Adding `capitalCostSummary_USD` into `capitalCosts_USD` totals | Summary rows are already subtotals/totals; show them separately | | Treating `quantityBasis` rows as USD costs | Quantity rows carry units like man-hour or vessel-day, not currency | | Comparing located process totals to base equipment rows | Use located `*_USD` equipment fields for reconciliation, base fields for pre-location analysis | | Claiming Class-3 accuracy on capacity-factored | Capacity factor (six-tenths) → Class 5; named in AACE 18R-97 | | Ignoring location | `setLocationByRegion("Norway")` ≈ 1.3× US Gulf Coast for offshore | | Adding a new mechanical design but leaving the base estimator | Assign the unit-specific `costEstimate` in the mechanical design constructor | | Passing shell weight to a volume correlation | Use `calc*ByVolume(volume_m3)` only with vessel volume | ## Validation Checklist - [ ] CEPCI year matches the project base year - [ ] Material of construction set per stream service (e.g. SS316L for wet sour) - [ ] Pressure factor applied for design P > 10 barg - [ ] AACE class declared in report (5/4/3) with stated accuracy band - [ ] Stackup shown: Cp → Cbm → Ctm → Cgr with each multiplier - [ ] Currency and location factor stated - [ ] Additive cost rows, summary totals, supplementary breakdowns, and non-cost quantities are kept in separate `CostEstimateResult` maps - [ ] Process equipment rows reconcile on the same basis as totals: located-to-located or base-to-base - [ ] JSON saved via `cost.toJson()` to `results.json` under `capex` section - [ ] Sensitivity to ±20% on key drivers (compressor power, column trays) reported - [ ] Full-process screens include major reservoir-to-market equipment rather than only topside separators and compressors - [ ] New equipment classes expose a specialized mechanical design and estimator before relying on `ProcessCostEstimate` ## Related Skills - [`neqsim-field-economics`](../neqsim-field-economics/SKILL.md) — project NPV / IRR / fiscal - [`neqsim-api-patterns`](../neqsim-api-patterns/SKILL.md) — `CompressorDesignFeasibilityReport` includes integrated cost - [`neqsim-standards-lookup`](../neqsim-standards-lookup/SKILL.md) — AACE 18R-97