Engineering Calculators

Shell and head thickness to ASME VIII-1 (UG-27, UG-32), the plate to buy, the MAWP it gives you and the hydrotest pressure — with the formulas shown.

Working stress and factor of safety against yield for a loaded member, with a pass/warn/fail band and the allowable load for a target factor.

Friction loss for water in a pipe — velocity, Reynolds number, Swamee–Jain friction factor, Darcy–Weisbach head loss in feet and psi.

Resistance, power and conductance from a voltage and a current — V = I·R and P = V·I, solved for a DC circuit.

Open-belt length for two pulleys at a centre distance, the wrap angle on the small pulley, and the speed ratio.

Hydraulic horsepower, brake horsepower and motor input kW for a pump from flow, head, specific gravity and efficiencies.

NEC copper ampacity for AWG 14–2 at 60/75/90 °C, plus the voltage drop and percent drop over a run at your load current.

Series and parallel totals for any list of resistors — add or remove resistors and both equivalents update live.

Compression-spring rate from wire size, coil diameter and active coils, plus the load at a deflection, spring index, Wahl factor and shear stress.

Gallons in a horizontal or vertical cylindrical tank — total capacity, the liquid at a measured level, and percent full.

Sheet-metal bend allowance, bend deduction and flat-pattern length from thickness, inside radius, bend angle and two flange lengths.

Length change of a steel, aluminum, copper or stainless member over a temperature change, and the stress if it is restrained.

Gear or pulley ratio from tooth counts or diameters, with the output speed and torque for a given input rpm, torque and efficiency.

Deflection, bending moment and stress for a simply supported or cantilever beam under a point or uniform load — rectangular or round section, with an L/360 check.

Output voltage of a two-resistor divider, plus the loop current and the power dissipated in each resistor.

Tightening torque and clamp load for UNC ¼–1 in and M6–M20 bolts by grade or class, dry or lubricated — T = K·F·d.

Itemized operating-torque calculator for concentric (resilient-seated) butterfly valves: seating + bearing + packing, with manufacturer calibration and actuator sizing. Built around the AWWA M49 component method.