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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.
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TECHNICAL DATA
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Diameter of test specimen
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16 ± 0.2 mm
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Height of test specimen
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6 to 10 mm
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Diameter of rotating drum
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150 mm
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Length of rotating drum
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470 mm
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Speed of rotation of cylinder
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40 ± 2 RPM
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Lateral movement of test specimen holder
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4.2 mm per revolution of drum
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Load on test specimen
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10 N / 5 N
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Inclination of axis of specimen holder
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3º from vertical
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Total length of abrading run
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40 m (about 84 rotations)
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Abrasive cloth
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450 mm wide x 473 mm long coated With aluminium oxide abrasive grain of 60 grit
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Motor
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¼ HP - 230 volts AC
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RELATED STANDARDS
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IS 3400 (Part 3)  1987
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Methods of Test for Vulcanised Rubbers
Part 3 : Abrasion Resistance using a Rotating Cylindrical Drum Device
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DIN 53516
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Testing of Rubber and Elastomers - Determination of Abrasion Resistance
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ISO 4649  1985
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Rubber  Determination of Abrasion Resistance using a Rotating Cylindrical Drum Device
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