How to read an old pneumatics part number

A part number copied from an old label, with no document beside it, fails as a buying instruction. Match the characters to a document you hold, and write down what that document says the number is.

Match the characters to a document you hold, and write down the title, date, language and any standard that document prints. Earlier use of this domain is described on the about page.

A similar string of digits is not an equivalent part. The legacy documents section is this one note.

Copy the fields that are already on the paper

Write the document title, the date printed on it, the language, and any standard the page names. Two standard numbers that show up in public cylinder writing, not in a catalog on this site, are ISO 15552 and ISO 21287.

Josh Cosford’s “A designer’s guide to pneumatic cylinders” (Pneumatic Tips, 26 January 2026) mentions ISO 21287 as a compact, square-body construction. He writes that such cylinders are normally unique designs and are not interchangeable between manufacturers. A Fluid Power World article, “Time-honored process embraces food-safe pneumatics” (published 10 August 2018), states that the cylinders discussed there meet ISO 15552 and ISO 21287. Those sentences show that public cylinder writing names those two standards. The old number still has to be read from the document that printed it.

Match the digits to the paper

If the document you hold explains its own fields, copy that explanation onto your note and keep the page number. If it does not, stop. A neighbouring number in a list is not a substitute.

Keep the new notes separate

The current notes ask different questions. The cylinder page wants load, port pressure, stroke and mount. The air preparation page wants a purity class written as particles, water and oil. Neither page accepts an old catalog number as a specification.