Hydraulic Cylinder & Pump Sizing Engine

Calculate required bore diameter, fluid displacement, pump GPM, and engine shaft horsepower for log splitters and presses.

1. Enter Build Requirements

Standard log splitters: 20–28 tons. Shop presses: 12–50 tons.
Continuous relief valve setting on directional control valve.
Time required for the ram to push fully outward under no-load high flow.

2. Hydraulic Engineering Specs

Recommended Standard Cylinder Bore:
4.0" Bore × 24" Stroke
Actual Output Force: 18.8 Tons @ 3,000 PSI
Required Pump Delivery Flow (GPM):
16 GPM (2-Stage Hi-Lo)
Extension: 9.0s | Retraction: 6.8s (w/ 1.75" Rod)
Fluid Displacement Per Extension Stroke:
1.31 Gallons
Minimum hydraulic oil tank reservoir size: ~5.0–6.5 Gallons.
Minimum Gas Engine Horsepower (Shaft HP):
8.5 HP (Gas Engine)
Based on 2-stage unloader kick-down @ 650 PSI transition.

Verified Hydraulic System Components

Hydraulic Ram

Welded Hydraulic Cylinder

Heavy-duty welded cylinder sized to match your calculated bore, stroke, and continuous pressure rating.

View Matching Cylinders
Power Unit

2-Stage Hydraulic Gear Pump

Hi-Lo rapid-advance gear pump delivering rapid cycle times with high-pressure kick-down when splitting knots.

View Matching Hydraulic Pumps
Flow Control

Auto-Return Detent Valve

Heavy-duty log splitter directional control valve with hands-free pressure-release detent and built-in relief valve.

Shop Auto-Return Valves

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Fluid Dynamics & Safety Disclaimer: High-pressure hydraulic circuits operate under hazardous energy capable of severe structural fatigue, component burst, and fatal fluid injection injuries. Calculations provided by this software are theoretical mathematical estimations for design planning only. All hydraulic cylinders, pumps, hoses, fittings, and reservoir tanks must be physically rated to safely exceed peak circuit relief pressures. Never inspect pressurized hydraulic lines with bare hands, and always use certified safety relief valves in hydraulic circuits.