D. SCREEN VIBRATOR BEARING TEMPERATURES
The screen vibrator unit, by reason of its functional purpose, is subjected to strain. For this reason frequent and regular
inspection should be made to be sure that all cap screws securing the bearing housing flanges and mounting connections
are kept tight.
The bearings normally operate at a temperature of 1000 to 180°. If a bearing is running at temperatures in excess
of 1800, it is considered as over-heating and the cause should be found and corrected to prevent damage.
a. A magnetic type thermometer provides the best method of checking bearing temperatures. Place thermometer on
bearing housing close to bearing immediately after stopping screen. Temperature will increase slightly above
operating temperature for approximately the first five minutes.
b. Bearing temperatures can be checked by placing the hand on the bearing cartridge or housing; if the hand can be
held there for a few seconds the bearing is not too warm. However, make all final checks with a thermometer.
2. BEARING HEATING CAUSES
a. Most common causes of overheating is too much lubricant and most generally occurs when the unit is new or
immediately after lubricant has been changed.
b. Incorrect type or grade of lubricant can cause overheating and improper lubrication of bearings. Always use
c. The bearings will overheat if the screen is operated faster than recommended. Check the speed with the speed
indicator and correct if necessary.
d. A broken or improperly adjusted spring will create a condition that can cause the vibrator unit bearing to overheat.
e. Overheating is also a sign when bearing failure is developing. Check the overheating bearing for wear. It will be
necessary to partially disassemble unit to expose bearing presumed failing, and by placing a pry bar under shaft
check movement of shaft.
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