1. The Tools we use

2. Course Content Course Duration - 1hr
Hazards and risks arising from use of Abrasive
Wheels and the Control Measures.
Inspection and Test.
Functions of Components - flanges, guards etc.
Proper PPE/RPE.
Health Risks - Noise Dust Vibration.

3. This course will give advice on the
prevention of accidents when using
Abrasive Wheels, in particular:-
Injury from breakage
Injury from contact
Injury from noise
Injury from dust & Fume
The impact of Noise, Vibration and
Dust will also be discussed.

4. An abrasive wheel is usually defined as a wheel consisting of abrasive particles bonded together using organic or inorganic substances such as resin. 4 4

5. The Risk of Breakage is inherent in every Abrasive Wheel
It is prevented by:-
Care exercised in design, in manufacture and testing
Safe measures by users.
Injury statistics show that nearly half of
accidents are due to an unsafe system of
work or operator error.

6. SAFETY - Wheel Breakage
Abrasive Wheel Manufacturers
carry out tests and inspection to
ensure the integrity of their wheels.
They will also reinforce wheels.
Resin coated glass fibre mats are
used in organic wheels to help
withstand high stresses and to
contain fragments

7. Bad storage and handling Incorrect selection of wheel
SAFETY - Wheel Breakage
Breakage may occur in service due to:-
Bad storage and handling
Incorrect selection of wheel
Improper mounting
Excessive imbalance
Excessive speed
Grinding machine defects
Malpractice
Two or more factors may act together.

8. Examination of Wheels
Visual check
Check classification for
suitability
Ensure suitability for
grinder - depressed centre or flat?
Ensure suitability for task
grinding or cutting?
If in doubt consult Supervisor

9. Safety and PPE

10. HAZARDS
Noise
Dust and Fume
Vibration
Contact with Wheel
Wheel Breaking
Risk to others

11. Noise
Depends on workplace
Depends on material
Grinders Always
Above 70db
Use protection
Think of others in area
Manage PPE

12. Dust and Fume
depends on environment
depends on material
paint removal
chemicals, temperature
wear PPE/RPE

13. use low vibration tools
keep hands warm
don’t grip too hard
maintain circulation
report problems
do not apply excessive
pressure

14. Contact with Wheel & Job
plan the job
get in a good balanced position
don’t over reach or stretch
don’t use unsuitable access

15. Wheel Breaking
Chose, right wheel for the task.
don’t bend or stress wheel.
ensure disc is compatible with grinder.
ensure disc is correctly fitted.
wear correct PPE for the task

16. Risk to others
plan the job
consider barriers
use sheeting or tents if possible

17. SPINDLE SPEED
Peripheral speed on a fixed speed spindle
will decrease as diameter of wheel shrinks.
Tendency to use more force - may cause
breakage, Change disc before it gets to low.
SPEED REDUCES
TEND TO USE MORE PRESSURE

18. Stresses on an Abrasive Wheel are greater nearer the hole.
FLANGES
Stresses on an Abrasive Wheel
are greater nearer the hole.
Hence flanges are fitted.
Flanges should be at least one
third diameter of wheel.
Therefore if unreasonable side
force is applied disc may break
Or disintegrate near centre.
STRESS
INCREASES

19. Reinforced resin bonded wheels Cutting or Grinding
Flat or depressed centre
Up to 230mm diameter
Portable Machines
May have smaller flanges G
Type 41
Type 42

20. Securing the Wheel
Fit freely but not loosely - if tight, spindle
could expand and crack wheel.
Central nut fixing - only tight enough to
prevent wheel slipping
After mounting
check speed
marked on wheel
or blotter is not
exceeded by
that marked on
spindle.
WHEEL
KEYS

21. Summary of Wheel Mounting Procedures
Trained Person
Compatible Machine
Inspect for damage
Flanges correct for wheel
Wheels and flanges free from
foreign matter

22. GUARDS - three main functions
To contain wheel if it bursts
2. To prevent operator coming in
contact with wheel.
3. Also protects wheel from damage
and prevents fitting of oversize
wheel.

23. Guards - for portable machines
Enclosure 1750
Front Lip 5mm

24. PORTABLE AND
HAND HELD GRINDING
MACHINES

25. Only organic bonded wheels to be used.
PORTABLE AND HAND HELD GRINDERS
Only organic bonded wheels to be used.
Cutting wheels should have fibreglass
reinforcement.
Machine guards must be securely in place
Guard between user and rotating wheel.
Serious often fatal incidents, when guard
removed to allow larger wheel to be
fitted.

26. ELECTRIC GRINDERS
Damaged cables are not to repaired
under any circumstances
Plug and sockets compatible
Regular Inspections by competent
electrician
Do not try to repair, return to stores
Always inspect daily before use

27. MZ12A768 CHOP SAW - maximum peripheral speed REINFORCED ORGANIC
ACME
MZ12A768
Type 41
REINFORCED ORGANIC
BOND m/s

28. SUMMARY OF PRECAUTIONS
Training
Housekeeping
Mounting of Wheels
Speed
Guards
Rests
Lubrication
New Wheels
Stopping Wheels
Overhang on Mounted Wheels

29. Thank you