Los Angeles Abrasion Testing Machine

The Los Angeles Abrasion Testing Machine measures the resistance of coarse aggregate to abrasion and degradation when subjected to a combination of impact and grinding action inside a rotating steel drum, along with a specified charge of steel spheres. After a set number of drum revolutions, the sample is sieved, and the percentage loss in weight (passing a specified sieve) is reported as the Los Angeles Abrasion Value. This is a widely used parameter for judging the durability and suitability of aggregate for road construction, particularly for wearing courses and base layers.

This machine is for determining the resistance to wear off small size coarse aggregates and crushed rock. The machine consists of a hollow cylinder, mounted on a sturdy frame on ball bearings. A detachable shelf which extends throughout the inside length of the drum catches the abrasive charge and does not allow it to fall on the cover. The drum is rotated at a speed of 30-33 rpm by an electric motor through a heavy duty reduction gear. Supplied complete with a tray for collection of the material.

The machine comprises the following :-

ⅰ) A hollow steel cylinder mounted on a sturdy frame on ball bearings capable of rotating about its axis in a horizon-tal position.

ii) A detachable shelf fitted inside the cylinder at a distance of 1250 mm from the opening measured along the circumstance in the direction of rota-tion.

iii) A motor with reduction gear which runs the drum at 30-33 rpm.

iv) A tray.

v) A revolution counter.

vi) Abrasive charge consisting of 12 steel ball approximately 48 mm dia and each weighing between 390 and 445 g. Suitable for operation on 440 v, 50 Hz, 3 phase supply.