Cylinder Size Calculator
Enter the force you need, the working pressure, the rod diameter and the stroke. The calculator works out the bore needed, picks the next standard bore and gives the push force, pull force and oil to extend.
- Bore size
- Push and pull force
- Oil volume
Allow 10 to 20% extra force for friction and pressure losses.
Bore area = force ÷ pressure. To push 50 kN at 150 bar, the piston needs 3,333 mm², a bore of about 65 mm. The next standard bore is 80 mm, which pushes about 75 kN. With a 36 mm rod it pulls about 60 kN.
Hydraulic cylinder chart
At 150 bar. Search for a force.
| Force (kN) | Bore needed (mm) | Standard bore (mm) |
|---|---|---|
| 5 | 20.6 | 25 |
| 10 | 29.1 | 32 |
| 20 | 41.2 | 50 |
| 30 | 50.5 | 63 |
| 50 | 65.1 | 80 |
| 75 | 79.8 | 80 |
| 100 | 92.1 | 100 |
| 150 | 112.8 | 125 |
| 200 | 130.3 | 160 |
| 300 | 159.6 | 160 |
Next standard bore.
Force and bore
150 bar. Slide the force.
The cylinder grows with the force.
How to size a hydraulic cylinder
Force to bore. Step through it.
Force
What it must push.
Long thin rods can buckle. Check the rod size for long strokes.
Single acting, double acting or telescopic
Cylinder types. Compare them.
Push only.
Both ways.
Long stroke.
Pull force is always less than push force because the rod takes up area.
Before you order
Cylinder checks. Tick each item.
Tick each item as you go.
Never exceed the cylinder's rated pressure, even briefly.
What you get
Cylinder sizing. Each tile explains one result.
Needed.
Size.
Force.
Force.
Volume.
Oil flow sets speed. More bore needs more oil for the same speed.
Frequently Asked Questions
No question matches that search.
How do I size a hydraulic cylinder?
Divide the force by the pressure to get the piston area, then work out the bore diameter.
What bore do I need for fifty kilonewtons?
At one hundred and fifty bar, about sixty-five millimetres, so an eighty millimetre standard bore.
Why is pull force lower than push force?
The rod takes up part of the piston area on the pull side.
How much oil does a cylinder need?
The piston area times the stroke.
What are standard cylinder bores?
Common metric bores include forty, fifty, sixty-three, eighty and one hundred millimetres.
How do I convert bar to psi?
Multiply by fourteen point five.
Should I add a safety margin?
Yes, about ten to twenty per cent for friction and losses.
Force where you need it
Size the bore from the force and pressure, and the cylinder moves the load smoothly every time.
More size calculators
Each one has its own calculator, worked examples and answers to common questions.