Grinding
Wheels are made with two basic components: abrasive
grains and a bond that holds these grains together.
The aluminum
oxide and silicon carbide grains that INABRA uses
have determined applications. They are synthetic materials,
not found in nature, with a respective hardness of
9 and 10 on the Mohs scale.
Think of abrasive
grains as millions of cutting tools held together
by a bond. They travel at high speeds, removing tiny
chunks of the workpiece with precision and efficiency.
We recommend
three types of aluminum oxide:
•
brown aluminum oxide - 95.0% or A
•
white aluminum oxide - 99.97% or AA
•
premium aluminum oxide - 99.8% or RU
"DA"
denominates mixtures of brown aluminum oxide and white
aluminum oxide. This mixture is well suited for several
applications.
The bond used
for aluminum oxide can be organic or vitrified, resinoid
or bakelite, rubber or shellac. Each has specific
applications.
For silicon carbide,
we use the following bonds:
•
vitrified or organic, denominated by the letter "V";
•
bakelite or risinoid - "B";
•
rubber - "R";
•
shellac - "E".
Vitrified grinding
wheels comprise assorted compounds and additives,
vitrified at high temperatures. These wheels are extremely
abrasive, resistant, and porous. They are used for
deburring and precision grinding on steel, iron, nonferrous
metals, and ceramics. Vitrified wheels are not affected
by variations in temperature.
Resinoid wheels
are manufactured using abrasive grains, phenolic resin,
and a plasticizing agent. They are frequently used
for cut-off operations or for applications that require
rapid stock removal with little regard for precision.
Resinoid wheels
remove stock metal quickly and are often used in foundries,
fabrication shops, and welding shops. A glass fiber
mesh can be added for reinforcement at speeds up to
80 meters per second.
Rubber bonds
are especially suited for smooth grinding operations,
and are often used on delicate tools. Rubber wheels
are multipurpose; in a single application they grind,
sharpen, finish, and polish.
Shellac wheels
have specialized applications, such as finish grinding
for cutlery, camshafts, crankshafts, etc.
Organic bonded
wheels are vulnerable to alkali solutions, such as
caustic soda, and to oil. Necessary precautions should
be taken in their use.
