Piping & Head Loss
Equivalent Length
Equivalent length Le = (Le/D) x D. Typical Le/D: 90 elbow 30, tee run 20, gate 8, globe 340.
Open calculatorCalculator category
Piping & Head Loss calculators
Piping head loss, velocity, and friction calculators for water-like and viscous screening. Enter pipe ID, length, roughness, fittings, and flow to estimate velocity, Reynolds regime, Darcy-Weisbach friction loss, equivalent lengths, and the system curve. Every output carries its formula and units, with links to the head-loss guides for pump-head matching and NPSH verification.
Piping & Head Loss
Friction Loss (Darcy-Weisbach)
Darcy-Weisbach screening: laminar f=64/Re, turbulent Blasius f=0.316/Re^0.25.
Open calculatorPiping & Head Loss
Gas Pipeline Pressure Drop (Screening)
Single-pass gas line drop with Haaland friction.
Open calculatorPiping & Head Loss
Hydraulic Diameter
Dh = 4A/P plus equivalent circular diameter.
Open calculatorPiping & Head Loss
Minor Loss (Fittings & Valves)
Minor loss dP = sumK x rho v^2 / 2. Enter K from table help.
Open calculatorPiping & Head Loss
Pipe Diameter from Velocity
Required inner diameter from flow and target velocity, round up to standard DN.
Open calculatorPiping & Head Loss
Pipe Velocity
Mean velocity from flow and inner diameter: v = Q/A.
Open calculatorPiping & Head Loss
Pipe Wall Thickness (Barlow)
Barlow wall with mill and corrosion allowance.
Open calculatorPiping & Head Loss
Reynolds Number
Reynolds number Re = rho v D / mu. Regime: 0 laminar, 1 transitional, 2 turbulent.
Open calculatorPiping & Head Loss
System Curve Builder
System curve H = H_static + kQ^2. Calibrate k from one known duty point.
Open calculator