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API RP 14E
// DH-101 · Module 6 · Line Sizing Tools
API 14E Erosional Velocity
Line Sizing Calculator
Determine the erosional velocity limit and check actual flow velocity against API RP 14E criteria for liquid, gas, and multiphase flow in oil & gas production and process piping.
Input Parameters
Flow Regime
Empirical Constant Cdimensionless
API 14E: C=100 (continuous) | 125-150 (intermittent) | 75-80 (solids)
Fluid Densitylb/ft³
Liquid density at flowing conditions. Water≈62.4, crude≈50-55, condensate≈40-48.
Pipe Internal Diameterinches
2″ Sch40=2.067″, 4″ Sch40=4.026″, 6″ Sch40=6.065″, 8″ Sch40=7.981″
Volumetric Flow Rate QBBL/day
Results
Results: Erosional velocity Ve, Actual velocity Va, Erosion ratio Va/Ve, and verdict per API 14E.
Erosional Velocity Ve
—ft/s
Actual Velocity Va
—ft/s
Pipe ID Used
—in
Flow Area
—in²
Velocity Ratio Va/Ve—
Engineering Recommendation
Formula Reference
API RP 14E — Erosional Velocity
Ve = C / √ρm
Ve=Erosional velocity (ft/s) | C=Empirical constant | ρm=Fluid/mixture density (lb/ft³)
Mixture density: ρm = ρL·λL + ρG·(1−λL)
Actual velocity: Va = Q/A
Mixture density: ρm = ρL·λL + ρG·(1−λL)
Actual velocity: Va = Q/A
Gas Density
ρG = (P×M)/(z×R×T)
R=10.7316 psia·ft³/lb-mol·°R | T in °R=(°F+459.67)
API 14E — C Factor Guide
| Service / Condition | C Value | Notes |
|---|---|---|
| Continuous service — no solids | 100 | Standard default for clean production fluids |
| Intermittent service | 125–150 | Start-up lines, low-frequency operations |
| Solids/sand present | 75–80 | Use corrosion-resistant piping material |
| Corrosive service (H₂S, CO₂) | ≤100 | Consult NACE MR0175 / corrosion allowance |
| CRA / stainless lined pipe | 150–200 | With materials engineer approval only |
⚠ Engineering Disclaimer: For educational and preliminary design purposes only — DH-101 by Design Hub India. Verify with a qualified process engineer and simulation software (HYSYS, PIPESIM) before use in final design.
