Variable Rotational Speed
Recommended Settings, Rota-
tional Speed
What happens when the
rotational speed changes?
Ordinary cut-off wheels, based on
bakelite-bonded siliciumcarbide
(SiC) or aluminiumoxide (Al
change their properties with the
rotational speed.
The higher the speed, the 'harder'
the properties of the wheel, and
vice versa. The benefit of a higher
speed is that the wheel wears at a
slower rate. At the same time, the
workpiece becomes more prone to
heat damage, which is countered
by reducing the feed speed.
Using a slower rotational speed,
the same wheel becomes softer,
and capable of cutting through
harder materials, with less risk of
workpiece damage. The downside
is increased wheel wear.
Struers have optimised both
rotational and feed speed, as per
the table and graph shown.
16
Discotom-50
Instruction Manual
Discotom-50 is fitted with a variable rotational speed feature.
This allows you to optimise cutting quality and cut many different
materials using the same cut-off wheel. Thus materials as
different as aluminium and hardened steel can be cut using the
same cut-off wheel.
The table below is a guide to recommended rotational speed
settings for popular materials using a single cut-off wheel
(Struers 53UNI).
Rotational Speed Settings using 53UNI cut-off wheel
Metalog Guide
Description
O
),
2
3
Non ferrous
Very ductile metal
Medium soft ferrous
Medium hard metal
Hard ferrous metal
Please note that the above settings are based on lab tests of the
specific materials listed above. Any deviation in material will
require a different setting. Interpolate the Vickers hardness to
approximate the corresponding rotational speed.
Material
Tested
Aluminium
soft metal
Stainless steel
UHB IMPAX
metal
Cold work tool steel
UHB IMPAX
Cold work tool steel
UHB ARNE
Cold work tool steel
Hardness
Speed
(HV)
(RPM)
50-110
3000
220
2200
300
2200
480
2000
750
1750