ISO 15552 cylinder interchange — what actually matches across brands
The standard fixes the mount, not the whole part. Here is exactly what you can swap, and what you still have to check.
ISO 15552 fixes the mounting dimensions and the rod-end thread of a profile cylinder for each bore. So any two cylinders that both declare ISO 15552 conformance — SMC C96 and AirTAC SAI, for example — share the mounting pattern and the rod-end for a given bore, and swap on the mount without re-drilling. What the standard does not fix, and what you still have to match, is the port thread, the seal compound, the minimum operating pressure, and cushioning detail.
What ISO 15552 standardizes
ISO 15552 (current edition 2018, revising the 2004 edition) sets a metric series of basic, mounting, and accessories dimensions “as required for interchangeability” of single- and double-rod pneumatic cylinders with detachable mountings, for bores 32 to 320 mm at a maximum rated pressure of 1000 kPa (10 bar). In practice that means, for a given bore, these are fixed and match across conforming brands:
- The mounting-interface dimensions and hole pattern
- The rod-end (male) thread — e.g. M10×1.25 at bore 32, M16×1.5 at bores 50 and 63
- The overall mounting envelope for the bore
What it does not standardize — so you still check these
The specs that decide whether a same-bore swap actually works in your line are the ones ISO 15552 leaves to the manufacturer:
- Port thread. Form and standard vary by maker and order option — see port threads: G (BSPP) vs NPT.
- Seal compound. NBR, TPU, or FKM/Viton — this decides the medium and temperature the cylinder tolerates.
- Minimum operating pressure and cushioning. These differ between makers even at the same bore.
Worked example: the SMC C96 to AirTAC SAI cross-reference matches on mount, rod-end, and pressure ceiling, and differs only on port thread, seal default, and minimum pressure — all of which you set when you order.
Reading a cylinder’s standard mark
A series that declares ISO 15552, ISO 6431, or VDMA 24562 is commonly treated as the same mounting family — the numbers are widely described as the same interface, with ISO 15552 the current designation. Do not assume a cylinder conforms just because it looks like a profile cylinder; confirm the maker’s own compliance statement for that series and bore.
Frequently asked
What does ISO 15552 actually guarantee?
ISO 15552 fixes the mounting dimensions and the rod-end thread for each bore of a detachable-mounting profile cylinder (bores 32 to 320 mm, up to 10 bar). So two cylinders that both declare ISO 15552 conformance share the mounting pattern and rod-end for a given bore — you can swap one for the other on the mount without re-drilling.
Can I swap any ISO 15552 cylinder for any other?
On the mounting, yes, for the same bore. But ISO 15552 does not fix the port thread, the seal compound, the minimum operating pressure, or cushioning detail — so those still have to be checked and matched. The mount is interchangeable; the full part is an equivalent-with-changes.
Does ISO 15552 cover the port thread?
No. The port thread is one of the things the standard leaves to the manufacturer. SMC ships a G (BSPP) port; other makers may default to a different thread with G as an option. Always confirm the port callout separately.
Is ISO 6431 the same as ISO 15552?
They are treated as the same mounting family. ISO 15552 is widely described as the successor to ISO 6431 and VDMA 24562, and many catalogs still reference the old numbers — AirTAC's own catalog labels its series 'ISO15552 (original ISO6431)'. If a cylinder is marked ISO 6431 or VDMA 24562, treat it as the same mount, but confirm the current ISO 15552 compliance statement.
Sources
- ISO 15552:2018 §1 (Scope) and §4.2 — metric mounting/accessories dimensions for interchangeability; bores 32–320 mm, 10 bar.
- SMC C96 product page — “Series C96 cylinders conform to ISO 15552”; AirTAC SAI catalog — “ISO15552 (original ISO6431) standard cylinder.”
Matching an ISO 15552 cylinder?
Send us the part you run today. We confirm the mount, the port thread, and the seal against the primary catalogs before you commit.