engineering-toolbox
Engineering Toolbox
Hydraulic · Pneumatic · Mechanical · Electrical · Fluid Power — All calculations run in-browser
Units:
Hydraulic Cylinder Calculators Bore Area · Rod Area · Force · Pressure · Speed · Flow · Continuity · Rod Buckling
Rod End Area in²
in²
in
Must be less than bore diameter
—
A_rod-end = A_blind − π × (d_rod / 2)²
Extension & Retraction Force
psi
Typical: 1,500 – 5,000 psi
in²
in²
—
F_ext = P × A_blind | F_ret = P × A_rod-end
Pressure to Lift a Load
lbf
in²
—
P = F / A
Cylinder Speed
gpm
in²
—
v = 231 × Q / (60 × A) → in/s
Flow for Stroke Time
in²
in
sec
—
Q = (A × L / 231) × (60 / t) → gpm
Retraction Continuity rod-in → blind-out
in²
in²
gpm
—
Q_blind = (A_blind / A_rod) × Q_rod
Rod Buckling Check Euler
in
in
lbf
—
F_cr = π²×E×I / (K×L)² [Steel: E=30×10&sup6; psi]
Disclaimer: Results are for engineering guidance only. Always validate against OEM specifications and applicable safety standards before use in safety-critical applications.
Gear Pump Calculators Displacement · Horsepower · Flow · Replacement Sizing
Replacement tip: Match displacement (in³/rev) for equal flow at the same drive speed. Measure gear width W, bore diameter D, and bore-to-bore center length L. See tutorial video below.
Gear Pump / Motor Displacement in³/rev
in
in
in
in
—
Precise (root dia. known): Disp = (π/4) × (D² − d²) × W
Quick approx. (center distance only): Disp ≈ (π/2) × W × (D² − L²) (±10–15% typical)
Shop Gear Pumps → Quick approx. (center distance only): Disp ≈ (π/2) × W × (D² − L²) (±10–15% typical)
Hydraulic Horsepower
gpm
psi
Typical gear pump max: 3,000 psi
—
HP = Q × P / 1714
Flow from Displacement & Speed
in³/rev
RPM
Typical: 600 – 3,000 RPM
—
Q = Disp × RPM / 231
Displacement from Flow & Speed
gpm
RPM
—
Disp = Q × 231 / RPM
Video Tutorial — How to Measure a Gear Pump for Replacement
Disclaimer: Displacement figures are engineering estimates for cross-reference purposes. Always confirm against the OEM part number or nameplate before ordering a replacement.
LSHT Motor Calculators Low-Speed High-Torque · HP · Speed · Torque · Flow · Displacement
Motor Speed from HP & Torque
HP
lbf·ft
—
RPM = HP × 5252 / T
Torque from HP & Speed
HP
RPM
—
T = HP × 5252 / RPM
Torque from Displacement & Pressure
in³/rev
psi
0 – 1
—
T = (P × Disp × η) / (2π × 12) → lbf·ft
Pumps & Power Unit Calculators Flow Rate · Power · Reservoir · Complete HPU Sizing
Hydraulic & Shaft Power
gpm
psi
0 – 1
—
HP_hyd = Q×P/1714 | HP_shaft = HP_hyd/η
Reservoir Sizing
gpm
×
—
V_tank ≈ (3 – 5) × Q
Complete HPU Sizing Worksheet Full System
Enter your cylinder and cycle requirements — get a complete pump, motor, and tank specification in one step.
lbf
in
in
sec
RPM
0 – 1
—
Pneumatic Calculators Cylinder Force · Speed · Air Consumption · Hose Burst Pressure
Pneumatic Cylinder Force
psi
Typical shop air: 60 – 120 psi
in
in
—
F_ext = P×π×(D/2)² | F_ret = P×(A_bore−A_rod)
Shop Pneumatic Cylinders → Air Consumption per Cycle
in
in
in
psi
—
Full extend + retract cycle. Multiply SCF × cycles/min for required SCFM.
Hose / Pipe Burst & Working Pressure Barlow
in
in
psi
× (min 4:1)
—
P_burst = 2×t×S/ID | P_work = P_burst/SF
Shop Hose & Fittings → Note: Pneumatic calculations assume dry air at standard conditions (14.7 psia, 68°F). Actual performance varies with temperature, humidity, and system efficiency. This Barlow formula convention (using inside diameter) matches SAE J517 hose practice; for rigid pipe per ASME B31.3, use outside-diameter based calculations instead.
Electrical Calculators Ohm’s Law · 1Φ/3Φ Motor Power · NEC Voltage Drop
Ohm’s Law Solve Any Unknown
Leave exactly one field blank — the missing value is solved automatically.
V
A
Ω
—
V = I×R | I = V/R | R = V/I
Motor Power 1Φ / 3Φ
V
Common: 120, 240, 480 V
A
0 – 1
0 – 1
—
P_3Φ = √3×V×I×PF | HP ≈ P×η / 746
Voltage Drop Copper · NEC
ft
A
V
—
Ω/1000 ft at 75°C Cu, NEC Ch.9 Table 8 · Loop = 2 × length · Ampacity: NEC 310.16
Mechanical Calculators Gear Ratio · Beam Deflection · Torque · Shaft Sizing
Gear Ratio
—
i = N_out / N_in | output RPM = input RPM / i
Beam Deflection Simply Supported · Center Load
lbf
ft
psi
in&sup4;
—
δ = F × L³ / (48 × E × I)
Torque
lbf
ft
—
T = F × r
Shaft Diameter Torsion Sizing
lbf·in
psi
—
d = ∛(16 × T / π × τ)
Advanced Fluid Tools Viscosity · Pressure Drop · Cv · Orifice · Heat Rejection · Hoop Stress · Accumulators · Line Velocity
Fluid Viscosity vs. Temperature ASTM D341
°F
Normal operating range: 100 – 160°F
—
Uses ASTM D341 Walther equation: log·log(ν+0.7) = A − B·log(T_K)
Pressure Drop Darcy–Weisbach
gpm
in
ft
lb/ft³
cP
AW-46 at 100°F ≈ 46 cP · at 140°F ≈ 20 cP
in
—
Swamee–Jain (turbulent) | f=64/Re (laminar, Re < 2300)
Line Velocity & Recommended ID
gpm
ft/s
—
Rules: Suction 2–4 ft/s · Pressure 10–20 ft/s · Return 6–10 ft/s
Orifice Flow Liquids
in
psi
lb/ft³
—
Q = Cd × A × √(2ΔP / ρ)
Heat Rejection & Cooler Sizing
gpm
psi
0 – 1
—
HP_loss = HP_in×(1−η) | BTU/h = HP_loss×2545
Shop Coolers → Pipe / Hose Hoop Stress & Safety Factor
psi
in
in
psi
—
σ_hoop ≈ P×ID/(2t) | SF = S_ult / σ
Accumulator Sizing & Energy
psi
psi
gal
—
Energy Stored
psi
psi
gal
—
Disclaimer: Always validate against OEM data and applicable engineering and safety standards before use in safety-critical applications.
Unit Conversions Length · Pressure · Temperature · Flow · Force · Torque · Power · Viscosity
Length
—
Pressure
—
Temperature
—
Flow Rate
—
Force
—
Torque
—
Power
—
Viscosity
—
For oil: cP ≈ cSt × SG. SSU ≈ 4.635 × cSt (for cSt > 32).
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Contact Information
Product / System Requirements
psi
gpm
—
Or contact us directly: 734-479-9641 | [email protected]
Note: "Send Quote Request" opens your email app pre-filled with your details. If that doesn't work on your device, use "Copy Details" and paste into any email. Your entries are saved locally so you won't lose them if you switch tabs.
Note: "Send Quote Request" opens your email app pre-filled with your details. If that doesn't work on your device, use "Copy Details" and paste into any email. Your entries are saved locally so you won't lose them if you switch tabs.
Help & Usage Notes
How to Use This Toolbox
- Select a category tab at the top, fill in the input fields, then tap Calculate or press Enter.
- Tap Copy on any result box to copy the value to your clipboard.
- Use the US / Metric toggle in the header to switch unit systems instantly.
- Tap the ? icons next to labels for context, typical ranges, and engineering notes.
- On the Hydraulic tab, → Send to buttons pass an area result into another calculator automatically.
- All calculations run entirely in your browser — no data is sent to any server.
- Ohm’s Law: Leave exactly one field blank — the solver fills it in automatically.
- Accumulator: n=1.0 isothermal (slow), n=1.4 adiabatic (fast), n=1.2 typical.
- Darcy–Weisbach: Swamee–Jain for turbulent flow; f=64/Re for laminar (Re < 2300).
- Voltage Drop: NEC 310 copper table at 75°C; loop = 2 × one-way length. Ampacity: NEC 310.16.
- Rod Buckling: Euler column formula, steel E=30×10&sup6; psi. For slenderness ratio < 120, Johnson’s formula may be more accurate.
- Hose Burst: Barlow thin-wall formula. SAE J517 requires minimum 4:1 safety factor.
- Viscosity: ASTM D341 Walther equation. ISO VG grade = kinematic viscosity in cSt at 40°C.
Disclaimer: This toolbox is for engineering guidance only. Patriot Hydraulics / Federal Fluid Power assumes no liability for errors in data nor in the safe and/or satisfactory operation of equipment designed from this information. Always validate results against OEM data and applicable engineering and safety standards. Results do not substitute for qualified engineering judgment.