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How to Size and Replace a Pneumatic Cylinder

4 min read

A pneumatic (air) cylinder produces linear force and motion. Two numbers define what it does — bore and stroke — and a few more decide whether a replacement bolts straight in.

Bore and stroke

  • Bore: the piston diameter — it sets the force. Force ≈ air pressure × piston area, so a bigger bore pushes harder at the same pressure.
  • Stroke: how far the rod travels.
  • Single-acting (air one way, spring return) or double-acting (air both ways).

Standards make cylinders interchangeable

Many cylinders are built to ISO standards, so brands interchange when the standard, bore and stroke match:

  • ISO 15552 (profile / tie-rod) — the common industrial size.
  • ISO 6432 (round-body / mini) for small bores.
  • Plus compact, guided, and rodless styles.

Mounting and connections

  • Mounting: foot, front/rear flange, clevis, trunnion, or pivot.
  • Rod-end thread (male/female) and port size (e.g. G1/8, 1/4 NPT).
  • Cushioning (adjustable air cushions) and any sensor slots for reed/Hall switches.

We'll match it

Cylinders from Festo, SMC, Parker, Bosch Rexroth and Camozzi cross-reference when the standard, bore, stroke and mounting match. Send us the part number or those dimensions and we'll quote a replacement.

Need a part sourced?

Tell us the brand and part number — we source industrial parts from 4,000+ brands and reply with a written quote.

How to Size and Replace a Pneumatic Cylinder | AllPartsIn