Abrasives Have an Expiry Date Too: Markings, Stock Rotation and Storage

Cut-off wheels and grinding discs carry an expiry date, and it is written into the standard rather than offered as advice. This article covers which markings to check at goods-in, why only one family of bonds expires, how to run stock first in first out, and the three environmental factors that actually damage them in storage.

1. Start with the part fewest people know: they expire

Products for hand-held grinding whose bond type is B or BF — in other words the everyday cut-off wheels and grinding discs — must not be used after the marked expiry date, under EN 12413.

🔴 That is a requirement of the standard, not a maker's recommendation. The date is marked as month/year (04/2026, for example), and the bond type is always on the label; both pieces of information sit on the same label.

📌 Why only that family expires: these resinoid bonds absorb moisture and age over time, and once strength has fallen there is a burst risk at speed. Vitrified-bond products do not share the problem and carry no expiry date — the difference is the bond, not what the product looks like.

2. What to check on the marking at goods-in

With the expiry date included, incoming inspection comes down to four items:

🔴 And one rule with no exceptions: a tool whose marking cannot be clearly identified must never be used. If it cannot be read, do not gamble on it — this goes straight into the goods-in criteria.

For reading the code fields, see Reading Grinding Wheel Markings: Grain, Grit, Grade, Structure and Bond. For coated specs, see Reading Coated Abrasive Specs: Grain, Grit, Coating, Bond and Backing.

3. Which standard covers what

The three numbers are not versions of each other; they cover different things:

📌 oSa is not a standard but an organisation: leading makers joined it voluntarily and commit to continuous monitoring of product safety and quality. The mark means the product passed that system, and its testing requirements are set above the EN thresholds.

4. Stock has to be rotated first in first out

Once there is an expiry date, stock is managed differently:

🔑 What makes this awkward is that there is no symptom: an expired cut-off wheel looks entirely normal and spins up perfectly well. Only the strength has changed — and strength is verified at the moment it bursts.

5. Storage: three things actually damage it

Time is not the only factor; the environment ages it too. The rules are short:

📌 "Never bend" is aimed at thin products: once a cut-off wheel or a coated disc has been bent, the internal damage does not show from outside and only reveals itself on the machine. Same principle as the expiry date — what you can see is the appearance; what you cannot see is the strength.

6. Two more gates before it reaches the machine

Marking, stock age and storage all cleared, two things remain. They belong to other articles; this one only points at them:

For the first, see Mounting and Balancing a Grinding Wheel: Clearance, Flanges, Two-Stage Balancing and Amplitude Limits and Why Grinding Wheels Burst: Strength, Unbalance and the Checks Before Mounting. For the second, see How Fast Can an Abrasive Run: Same Sheet of Abrasive, Seven Times the Limit. For choosing a handheld cut-off wheel for the job, and what to do before and after cutting, see Choosing and Using Handheld Cut-Off Wheels: Abrasive, Grade, Reinforcement, and What to Do Before and After Cutting.

This article is part of Deburring and Surface Finishing: The Complete Guide - Which Tool, Which Material, and What to Do in Volume; that guide shows how the whole topic fits together.

Published: 2026-09-24 | Last updated: 2026-10-24