Pneumatic Cylinder Force & Air Consumption Calculator

Works out the theoretical push and pull force of an air cylinder from its bore and pressure, checks the load ratio, estimates the air used per cycle and per minute, and gives a rough speed from the supply flow.

How to use

1. Pick the "Cylinder bore" from the ISO list or choose "Other bore…". Untick "Use the standard rod diameter for this bore" to enter your own rod.
2. Enter the "Working pressure (gauge)", the "Stroke" and the "Cycles per minute".
3. Under "Load", enter the force or mass to move and a "Target load ratio" to see the smallest standard bore that meets it.
4. Optionally add the tube size and the "Available supply flow (ANR)" for the tubing air and an average speed.
5. Read the force, air consumption and speed, and compare other bores in the table below.

How it works

• Force = pressure × piston area: push uses π × D² ÷ 4, pull uses π × (D² − d²) ÷ 4 with the rod diameter d. 1 MPa × 1 mm² = 1 N.
• Air per cycle (litres, ANR) = (push area + pull area) × stroke × (P + 0.1013) ÷ 0.1013 ÷ 10⁶. Tubing adds 2 × tube volume × P ÷ 0.1013.
• Rod diameters follow ISO 6432 and ISO 15552; a maker's cylinder may differ. Real force is lower by seal friction, and the speed ignores pressure drops and valve response.

Questions and answers

How much force does a 50 mm air cylinder give at 0.5 MPa?

About 982 N pushing and, with a 20 mm rod, about 825 N pulling. At 0.6 MPa the push force is about 1,178 N.

What load ratio should I design for?

Common practice is 50 % or less for normal motion, up to 70 % for clamping or slow movement, and about 30 % for fast motion.

How do I calculate the air consumption of a cylinder?

Multiply the swept volume of both strokes by (P + 0.1013) ÷ 0.1013. A Ø50 × 100 mm cylinder at 0.5 MPa uses about 2.14 L per cycle, 43 L/min at 20 cycles.

Why is the pull force smaller than the push force?

On the retract side the rod covers part of the piston, so the pressure acts on a smaller area.