Hydraulics Calculators

These tools size the fluid-power side of a machine from first principles rather than a generic pressure-times-area widget. The hydraulic cylinder force calculator returns push and pull force separately, because retract acts on the annulus area only: F_push = P·A_p on extend and F_pull = P·(A_p − A_r) on retract, with the rod-area differential and a standard cylinder force chart shown so the asymmetry is never a surprise. The hydraulic cylinder speed calculator focuses that flow side into extend/retract speed design, stroke time, oil volume, cycle rate and required flow for a target stroke time. The hydraulic cylinder rod buckling calculator checks the same actuator as a compression column, comparing Euler rod buckling with rod yield and returning safety factor, required rod diameter and maximum unsupported length. The pneumatic cylinder force calculator uses the same area logic at shop-air pressures and applies an efficiency allowance for seal friction.

Past the actuator, the pump flow and HP calculator turns displacement and shaft speed into output flow, then into hydraulic and shaft power (kW = Q·p/600, divided by overall efficiency) so you can pick a drive motor. The hydraulic fluid velocity calculator turns that flow and actual line ID into oil velocity, line-type target utilization, required ID and Reynolds number for suction, return, pressure and case-drain circuits before a pressure-drop model is trusted. The hydraulic oil cooler sizing calculator carries that flow and pressure into a heat-load screen, estimating pump loss heat, duty-cycle load heat, required catalog cooler rating, selected-cooler utilization and oil temperature rise through the cooler from user-entered ETD and oil data. The pump NPSH calculator checks suction-side head from absolute pressure, static lift/flooded head, vapor pressure and suction-line loss before the pump curve is trusted. The orifice flow rate calculator estimates incompressible liquid restriction flow from Q = Cd·A·√(2Δp/ρ), with velocity and mass-flow output. For water treatment and process dosing, the chemical feed rate calculator converts water flow, ppm dose, product strength and specific gravity into metering-pump L/h, mL/min, gpd, pump setting and day-tank runtime, while the water softener sizing calculator turns hardness, iron allowance, daily gallons, regeneration interval and peak service flow into resin volume, usable grain capacity, gallons between regenerations and salt use.

The hydraulic hose pressure drop calculator adds hose length, oil viscosity, roughness and fitting K values to the velocity screen so it can estimate pressure loss, Reynolds number and heat loss in hose runs, while the pipe size by flow velocity calculator back-solves required pipe ID from Q/v before the pipe flow pressure drop calculator applies Darcy-Weisbach to water-like plumbing, hydronic and process piping with head-loss output. The pipe rolling offset calculator covers the field-layout side for pipefitters, combining rise and roll into true offset, travel, cut length after takeout, advance and roll angle. The pipe bend developed length calculator covers adjacent bend layout, using centerline radius and bend angle to return arc length, developed cut length, chord, setback, radius-to-OD ratio and blank margin. The pipe miter cut calculator lays out fabricated mitered elbows from actual OD, total turn angle and piece count, returning cut angle, joint deflection, long-to-short difference and wrap-around template drops. The pipe saddle cut calculator lays out centered branch and lateral coping templates from header OD, branch OD and branch angle, returning saddle depth, long/short points and 16-mark drops. The HDPE bend radius calculator handles the route-layout side for PE and utility pipe, using actual outside diameter and an entered bend-radius multiplier to screen minimum radius, curve length, available deflection, chord length and offset. The pipe support span calculator checks pipe-plus-fluid weight, hanger spacing, simply supported deflection and bending stress from actual OD, wall thickness, material stiffness and fill condition. The pipe thermal expansion calculator checks free growth or shrinkage, movement allowance, center-anchor movement, fully restrained stress and anchor force from pipe length, temperature change, material, OD and wall. The pipe insulation heat loss calculator uses cylindrical insulation resistance plus outside film resistance to estimate insulated Btu/h, heat loss per foot, bare-pipe comparison, surface temperature rise, annual energy and rough cost. The pipe pressure rating calculator uses a Barlow thin-wall screen to compare OD, wall, allowable hoop stress, joint efficiency, derating and design factor against an entered design pressure, with required wall and OD/t context. The water hammer pressure calculator uses the same flow and actual-ID workflow to estimate surge pressure, wave speed, critical closure time and pressure-rating margin from a fast valve closure or pump trip. The pipe volume calculator uses the same actual-ID workflow to estimate line capacity, contained liquid, fluid mass and fill or drain time. The expansion tank sizing calculator carries closed-loop system volume, fluid expansion, cold fill pressure, relief margin and tank precharge into required acceptance volume, minimum hydronic tank volume, selected-tank utilization and predicted maximum pressure. The pipe trench backfill calculator turns trench length, bottom width, depth, side slope, actual pipe OD, bedding zone and material factors into excavation, bedding, import backfill and loose spoil haul-off quantities. The pipe slope calculator handles gravity-pipe layout: fall, end invert elevation, percent slope, inches per foot and 1:n pitch ratio from run length or measured inverts. The catch basin sizing calculator carries that drainage lane into site work, using Rational Method runoff, grate open area and Manning outlet-pipe capacity from user-entered rainfall intensity and local assumptions. The trench drain sizing calculator covers linear channel drains, checking known flow or runoff against grate open area, rectangular channel capacity, outlet pipe capacity and required channel depth. The French drain sizing calculator extends that site-drainage lane into trench storage, subtracting pipe OD displacement from the gravel envelope, adding pipe internal volume and checking perforated-pipe capacity against design runoff. The swale capacity calculator screens the surface-drainage alternative with trapezoidal open-channel Manning capacity, velocity, required depth, freeboard and limiting drainage area. The sump pump capacity calculator turns area-based and measured inflow into required pump capacity at installed head, basin drawdown volume, pump run time, cycle rate and high-water reserve time. The culvert capacity calculator compares Rational Method runoff with circular or box barrel full-flow Manning capacity, full-flow velocity, required size and limiting drainage area for a road or driveway crossing screen. The O-ring gland calculator checks squeeze, stretch and gland fill before you go to a seal handbook, and the pneumatic air consumption calculator scales swept volume by the compression ratio to give free-air demand per cycle and per minute for sizing a compressor. The compressed air receiver sizing calculator then carries free-air demand, compressor FAD, event duration and cut-in/cut-out pressure band into required receiver volume, stored free air, selected-receiver utilization, reserve time and recharge time. The compressed air leak cost calculator turns measured SCFM or a round-orifice leak estimate into wasted compressor kW, annual kWh, yearly cost and repair payback from user-entered specific power and electric rate. The compressed air pipe sizing calculator then checks whether the air main or branch can carry SCFM at the selected pressure, using actual pipe ID, run length, roughness and fitting K to return line velocity, Darcy pressure drop, outlet pressure and required actual ID.

Built for hydraulics technicians, machine builders and fluid-power designers who want the governing formula, not a black box. Every result is unit-flexible across metric and imperial. New to actuator sizing? The walkthrough on how to size a hydraulic cylinder ties bore, pressure and load together step by step.