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AshToolbox Oil & Gas Petroleum Engineering Suite
Upstream Petroleum Engineering Suite • 100% In-Browser Privacy

Oil & Gas Engineering Calculation Suite

Enterprise-grade reservoir volumetrics, stochastic Monte Carlo estimation, Arps decline curve forecasting, multiphase pipe hydraulics, drilling ECD rheology, and upstream well economics.

✓ 100% Client-Side Field Confidential ✓ Literature Validated (Craft & Hawkins, Bourgoyne, Lee) ✓ Offline-Ready & Web Worker Multithreaded
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Petroleum Data Confidentiality Guarantee

Your well logs, production decline data, reservoir dimensions, drill string geometry, and fiscal price decks never leave your device. All calculations, regressions, and simulations execute 100% locally.

Typical Upstream Engineering Workflow

From fluid characterization to drilling hydraulics and financial valuation, our local in-memory bus pipes figures seamlessly across tools.

STAGE 1

Fluid PVT & Z

API, Bo, Bg, Z-factor

→ Z & Density
STAGE 2

Volumetrics

STOIIP & OGIP Monte Carlo

→ P50 In-Place
STAGE 3

Decline (DCA)

Arps decline fit & EUR

→ EUR & Profile
STAGE 4

Pipe & Pump

Flow hydraulics & BHP

→ Operating dP
STAGE 5

Drilling & ECD

Rheology & TVD trajectory

→ Safe Mud Window
STAGE 6

Well Economics

Cash flows, NPV10 & IRR

→ Hurdle Decision

Petroleum Engineering Workbenches 7 flagship engines

Beginner ~5 min read

API Gravity & Oilfield Unit Converter

Convert between API gravity, specific gravity, and density at 60°F with ASTM D1250 thermal VCF correction, multi-crude blending, and 150+ oilfield/SI units.

Formula: ext{API} = rac{141.5}{ ext{SG}_{60/60}} - 131.5, quad ext{VCF} = e^{-alpha_{60}Delta T (1 + 0.8alpha_{60}Delta T)}
Launch Workbench →
Advanced ~8 min read

Gas Z-Factor & PVT Optimizer

Calculate natural gas compressibility Z-factor using DAK, Hall-Yarborough, Papay, and Beggs-Brill correlations with Sutton/Standing pseudo-criticals and Wichert-Aziz sour gas correction.

Formula: Z = 1 + left(A_1 + rac{A_2}{T_{pr}} + dots ight) ho_r + dots, quad B_g = 0.028279 rac{Z T}{P}
Launch Workbench →
Intermediate ~8 min read

Pipe Flow Hydraulics & Pump Sizing

Model single-phase liquid flow via Colebrook-White, compressible gas flow (Weymouth/Panhandle), Beggs-Brill multiphase screening, erosional velocity, and centrifugal pump TDH/BHP operating points.

Formula: Delta P_f = f rac{L}{D} rac{ ho v^2}{2 g_c}, quad ext{BHP} = rac{Q cdot ext{TDH} cdot ext{SG}}{3960 cdot eta}
Launch Workbench →
Advanced ~9 min read

Drilling Hydraulics & ECD Simulator

Compute Equivalent Circulating Density (ECD) with annular pressure losses for Bingham Plastic, Power Law, and Herschel-Bulkley fluids from Fann viscometer readings and 3D Minimum Curvature directional surveys.

Formula: ext{ECD} = ext{MW} + rac{Delta P_{annular}}{0.052 cdot ext{TVD}}, quad au = au_0 + K gamma^n
Launch Workbench →
Intermediate ~8 min read

Arps Decline Curve Analysis (DCA) & EUR

Fit production histories to Arps Exponential, Hyperbolic, Harmonic, and Modified Hyperbolic models with terminal decline switches (Dmin) to forecast EUR and remaining reserves.

Formula: q(t) = rac{q_i}{(1 + b D_i t)^{1/b}}, quad ext{EUR} = Q_{cum} + Q_{remaining}
Launch Workbench →
Advanced ~9 min read

STOIIP / OGIP Monte Carlo Simulator

Calculate deterministic and probabilistic oil & gas in place with 10,000–100,000 Monte Carlo iterations, multi-parameter correlation matrices, and petroleum industry standard P90/P50/P10 exceedance curves.

Formula: ext{STOIIP} = 7758 cdot A cdot h cdot NTG cdot rac{phi(1 - S_w)}{B_{oi}} quad (P90 < P50 < P10)
Launch Workbench →
Intermediate ~8 min read

Well Cash Flow, NPV/IRR & Fiscal Economics

Model monthly and annual well cash flows, CAPEX/OPEX schedules, royalties, severance taxes, depreciation, and discounted cash flow metrics (NPV10, IRR, DPI, payout, breakeven oil price) with simple PSC templates.

Formula: ext{NPV} = sum rac{ ext{NCF}_t}{(1 + r)^t}, quad ext{IRR} implies ext{NPV}(r) = 0
Launch Workbench →
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Formula Library

Catalog of DAK, Arps, Colebrook, Fann rheology, and STOIIP equations with full proofs.

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Petroleum Glossary

A-to-Z dictionary of SPE, API, drilling hydraulics, PVT, and petroleum fiscal terminology.

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Validation Vectors

Automated unit-test benchmark reports matching Craft & Hawkins, Bourgoyne, and Standing-Katz.

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Engineering Disclaimer

Critical safety limits, non-substitution for certified software, and screening use terms.