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Operation
The tester basically consists of rigidly mounted
test roller, which is pressed using lever and
dead weight arrangement. The test roller is pressed
against a revolving friction wheel.
The friction wheel is with its lower third in
the test lubricant cup. The rotating speed is
such that sufficient quantity of lubricant will
always get to the contact surface of the test
piece and frictionwheel. Suitability of the lubricant
for different materials can be determined by changing
the material of wheel.
An elliptical wearing surface is formed due to
cross wise spindles. The surface area increases
as the test progresses with the increase in surface
area specific surface pressure between friction
wheel and test piece decreases and a load carrying
lubricant film is formed.
The formation of film in evident by sudden reduction
in grinding noise. The size of clearly marked
wear surface indicates lubricants load carrying
capacity. Friction co-efficient can be read from
the controller.
A variable speed drive permits testing at different
speeds: |
