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Rotary Drum (Din) Abrasion Tester
In applications where an elastomer is
subjected to frequent rubbing or abrasive actions as part of its use, it is
of prime importance to ensure that the formulation used has a fair degree of
resistance to abrasion.
One of the methods for determining the abrasion resistance of elastomers is
by a Rotating Drum Abrasion Tester. In this test the elastomer under test is
abraded against an abrading surface mounted over a rotating drum. The
abrading surface has a specified abrading power. The test specimen, which is
in form of a button, is held against it under a fixed load. The abrading
surface is made to rub against the test specimen by rotating the drum at a
fixed speed, the test specimen being meanwhile made to move along the axis
of the drum.
The ratio of the volume loss of a standard elastomer to the volume loss of
the rubber under test, determined under the same conditions and expressed as
a percentage, gives the abrasion resistance index of the rubber under test.
The determination of volume loss by this method is suitable for comparative
testing and for checking the uniformity of specified products. However, the
results of this test give only limited information on the wearing behaviour
of elastomers in practice.
The PROLIFIC Rotating Drum Abrasion Tester is designed to determine
abrasion resistance index of natural and synthetic rubbers in accordance
with the above principle. It consists of test specimen holder with a
cylindrical opening adjustable between 15.5 and 16.3 mm to clamp the test
specimen, with an arrangement to adjust the length of test specimen
protruding out.
The holder is mounted on a swivable arm pivoted in a bracket, which is
moved laterally by a screw mechanism along the length of a rotating drum on
which the abrasive cloth is fixed. The test specimen holder also provides an
arrangement to protect the abrasive cloth from damage by preventing the
lower edge of the test specimen holder to touch the abrasive cloth.
The movement to the screw mechanism and the drum is given by an electric
motor coupled to a worm reduction gearbox with V-belt and pulleys to give
the specified speed of rotation to the drum and the specified lateral
movement to the test specimen holder. The equipment is provided with limit
switches, which, in addition to giving over-travel safety to the movement of
test specimen holder, also stop the motor automatically after the specified
run of the test specimen.
The swivable arm and test specimen holder are so disposed that the test
specimen is pressed against the drum under the specified load with its
center axis at an inclination of 3° to the perpendicular in the
direction of rotation and placed above the longitudinal axis of drum.
The abrasive cloth is firmly fixed to the drum using a suitable peelable
adhesive with the ends of the abrasive cloth butt jointed together. Four
abrasive cloths in addition to the one fixed on the cylinder are supplied
with the equipment as standard accessory.
Molding die and rotary type cutting die (hollow drill) for preparing test
specimens and extra abrasive cloths are available as optional accessories.
TECHNICAL DATA |
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Diameter of test specimen |
16 ± 0.2 mm |
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Height of test specimen |
6 to 10 mm |
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Diameter of rotating drum |
150 mm |
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Length of rotating drum |
470 mm |
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Speed of rotation of cylinder |
40 ± 2 RPM |
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Lateral movement of test specimen holder |
4.2 mm per revolution of drum |
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Load on test specimen |
10 N / 5 N |
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Inclination of axis of specimen holder |
3º from vertical |
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Total length of abrading run |
40 m (about 84 rotations) |
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Abrasive cloth |
450 mm wide x 473 mm long coated With aluminium
oxide abrasive grain of 60 grit |
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Motor |
¼ HP - 230 volts AC |
RELATED STANDARDS |
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IS 3400 (Part 3)  1987 |
Methods of Test for Vulcanised Rubbers
Part 3 : Abrasion Resistance using a Rotating Cylindrical Drum Device
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DIN 53516 |
Testing of Rubber and Elastomers - Determination
of Abrasion Resistance |
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ISO 4649  1985 |
Rubber  Determination of Abrasion Resistance
using a Rotating Cylindrical Drum Device |
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