Humboldt H-3860A Los Angeles Abrasion Machine - Manual (Page 2)

General
Model H-3860 (Los Angeles Abrasion Machine) is designed to conform to ASTM C131,
C535 and AASHTO T96. These methods cover the procedure for testing crushed rock,
crushed slag, uncrushed and crushed gravel for resistance to abrasion in the Los Angeles
Testing Machine with an abrasive charge. This machine can be used for determining the
abrasion limits given in ASTM C33 (see attached table).
The drum is rotated by a 1.0 hp Electric Motor. A heavy-duty speed reducer converts
the motor speed to the required drum speed of 30 to 33 revolutions per minute. The
machine is equipped with an adjustable automatic counter that can be set to stop the
machine at the required number of revolutions.
Packing & Assembly
Each unit is shipped complete with a set of 12 charges and a collector pan. Generally the
collector pan and the carton containing the charges is wire strapped to the lower cross
members of this machine.
Electrical Motor and Speed Reducer
Examine the motor carefully to make sure that it has not been damaged during
shipment. Be sure that the line voltage and frequency correspond to those stamped on
the nameplate. For connections, see diagram attached to the machine.
CAUTION: On three phase models be sure that rotation of the drum is counter
clockwise as seen from drive end. More than momentary reverse rotation may damage
counter.
The ratio-motor gear housing is shipped with oil. Check the oil level and if necessary,
be sure to lubricate in accordance with the instructions on the motor plate and included
in this manual.
NOTE: U.S. Electrical Motors, Div. Of Emerson Electric Co., Operating Instructions for
the motor and for the right angle gear head are considered part of these instructions.
Pillow Blocks
The bearings in all Gear Pillow Blocks are pre-greased at the factory. When re-
lubrication is necessary use recommended ball bearing grease of medium consistency
and apply by means of an ordinary grease gun and the convenient grease fitting
provided.
DO NOT USE OIL FOR RE-LUBRICATION. Additions of grease every three or four
months is suggested unless experience proves otherwise. For normal usage, grease
having a temperature operating range from 0°F to 150°F is recommended.
Counter
Wiring: Connect the blue and black wires to the motor on-off switch in the control box.
Method of Operation: Subtracting in one direction of rotation, adding when rotation
is reversed. The counter subtracts from the preset figure down to zero where a contact
switch is released. For knock-off at 9999, refer to particulars under the heading “Control
Contacts.”
Setting: Depress reset push button and hold it down. Preset the required figure by
means of the individual push buttons (sequence immaterial). Release reset push button.
Repetition of count: By depressing the reset push button once, the counter is
automatically set for a repetition of the preset cycle.