Darcy–Weisbach Pressure Drop Calculator

ΔP = f × (L/D) × (ρ·v²/2)

Pipe Flow Rate ↔ Velocity Calculator

Q = A·v  and A = π·D²/4

Reynolds Number Calculator

Re = (ρ·v·D)/μ

Pump Power Requirement Calculator

P = (ρ·g·Q·H) / (η × 1000)

Pipe Wall Thickness Calculator (ASME B31.3)

t = (P·D) / (2·S·E + P·Y)

Head Loss from Fittings (K-Factor Method)

h_f = (ΣK · v²) / (2·g)

Thermal Expansion Stress & Elongation

ΔL = L·α·ΔT  and  σ = E·α·ΔT

Hydraulic Power & Efficiency Calculator

P_hyd = (ρ·g·Q·H) / 1000  η = (P_hyd / P_shaft) × 100

Valve Flow Coefficient Calculator (Cv ↔ Kv)

Kv = 0.865 × Cv   Cv = 1.156 × Kv

Actuator Torque & Sizing (Quarter-Turn)

Running torque is estimated from ΔP acting on the obturator area with a type-dependent coefficient.
Breakaway adds packing/seating effects. Then a safety factor is applied for actuator sizing.

Actuator Check (optional)

Note: Estimates for quarter-turn valves. For gate/globe (linear) valves, use a thrust calculator (different model) — I can add that next.

Pick the service and constraints; the app suggests valve type(s), materials, seat/trim, actuator, and a target Cv/Kv. Optional flow inputs compute Cv/Kv exactly.