Why does mounting an abrasive wheel need a procedure?
A wheel with the wrong speed rating, a hidden crack or a bad mounting can burst at full speed. HSE's guidance HSG17 covers the training people need before they mount wheels and the checks to make before a new wheel is run. Writing the steps down, with a photo of the machine's speed plate and guard settings, means everyone appointed to do the job does it the same way.
This is a template, so adapt it to your own procedure, equipment and risk assessment, and have a competent person approve it, before anyone uses it.
When: mounting a new wheel on a bench or pedestal grinder. Only people who have been trained and appointed to mount abrasive wheels should do this.
Before you start
The replacement wheel, the correct flanges and blotters, the right spanner, and eye protection.
Steps
- Isolate the grinder and lock it off.
- Check the wheel's markings. Its maximum operating speed must be the same as or higher than the spindle speed on the machine's plate, and its size and bore must match the machine.
- Check the expiry date if the wheel is resin-bonded and has one marked.
- Inspect the wheel for chips, cracks and damage. For a vitrified wheel, do a ring test: hold it by the bore and tap it lightly with a non-metallic tool. A clear ring is good; a dull sound means it must not be used.
- Check the flanges. Clean, flat, undamaged and matching in diameter.
- Mount the wheel with the blotters in place. It should slide onto the spindle without forcing. Never enlarge the bore.
- Tighten the nut only enough to hold the wheel firmly, following the manufacturer's instructions.
- Refit and adjust the guards. Set the work rest as close to the wheel as practicable and set the tongue guard to the manufacturer's setting.
- Run it up. Remove your lock, stand to one side and run the wheel at full speed for at least a minute with everyone clear of the line of the wheel.
- Sign off and record the wheel change.
Stop and report if the wheel's speed rating is lower than the spindle speed, the ring test sounds dull, or a guard is missing or damaged.
Toolbox talk
- Why do we stand to one side when a new wheel is first run up?
- Who on this site is appointed to change wheels?
- What happens if the work rest gap is too wide?
Further reading: HSE HSG17, Safety in the use of abrasive wheels. PUWER 1998.
These templates are general outlines for UK workplaces, provided free and without warranty. They do not replace your own risk assessment, training, supervision, permit systems or manufacturers' instructions. You are responsible for checking and approving any guide before it is used.