Page 482 - NORTON cutting-off and grinding wheels - industrial

482 TECHNICAL INFORMATION
TECHNICALINFORMATION
ABRASIVE TYPES
ABRASIVE
TYPE
DESCRIPTION
A This is a particularly tough form of aluminium oxide. Its toughness is due to the presence of 3% of titanium
oxide in the abrasive. Fired at low temperature the abrasive retains its natural brown colour. Fired at high
temperature further oxidation of the titanium oxide takes place which changes the normal brown colour
to a grey-blue. Because of its toughness, regular brown alumina is suitable for grinding high tensile strength
materials, specifically off-hand grinding (bench grinding wheels) & sharpening stones.
19A A blend of A & 38A abrasives. This abrasive gives a grinding action that can be compared to the average
of its components. It is supplied in some standard tool room wheels, used for surface, cylindrical, centreless
& miscellaneous grinding on less heat sensitive steels.
38A White fused aluminium oxide (99,8% pure). The most friable & cool cutting of the aluminium oxides.
This abrasive is supplied in all types of standard range wheels ideal for use on hard & heat sensitive steels
& alloys. It has traditionally been used for sharpening high-speed steel & cast alloy tools & cutters.
38A is used for cylindrical, surface & internal grinding of tools, dies & gauges.
57A Semi-pure brown fused aluminium oxide (98% pure). The higher purity of 57A makes it a good general
purpose abrasive. Its versatility enables it to be used for grinding steel parts in both soft & hard states,
especially on large cylindrical & centreless operations. U Treatment (U57A) is a ceramic coating applied
to this abrasive to increase its durability in resin bonded cutting-off wheels. It is used in the advanced range
resinoid cut-off wheels.
86A Pink aluminium oxide is a highly refined form of alumina containing a small proportion of chromium oxide.
This addition makes 86A a little tougher than pure white, increasing the strength along the shear planes.
This abrasive is available in a range of mounted points & wheels.
SGB A blend of premium abrasives that include a medium concentration of ceramic Norton SG.
3SG A blend of premium abrasives that include a high concentration of ceramic Norton SG.
5SG A blend of premium abrasives that include a very high concentration of ceramic Norton SG.
37C Crystolon silicon carbide abrasive. Supplied mainly in the resin bonds of advanced wheels used for grinding
grey iron, non-ferrous metals & in vitrified bonds for grinding non-metallic materials, such as rubber & stone.
39C Crystolon is the highest purity silicon carbide abrasive. It is ideal for grinding cemented carbide cutting tools,
fired ceramics & glass, where it provides advanced performance.
BOND TYPES
VITRIFIED
Vitrified bonds are the most common precision grinding bond. Porosity and strength of the wheels made
with this bond give high stock removal along with their rigidity helping to attain high precision. Not affected
by water, acid, oils or ordinary temperature variations. The most common vitrified bonds are:
V V is the original high temperature vitrified bond, usually used where tougher acting wheels are required
VS VS is a very versatile, low temperature, high performance vitrified bond system used in almost all applications
but predominately for tool room, centreless, cylindrical, & surface grinding
VTECH Low temperature, very technical bond, used with conventional abrasives & recommended for high tech
applications to maximise performance & dressing parameters
VX VX bond provides improved corner/form holding for most applications – it is the first choice bond for our
premium abrasives
VXP Induced porosity VX bond suitable for large contact areas & surface grinding