Specifications

OPERATING INSTRUCTIONS Document No. DER04098
Effective Date 06 Jun 08 Page 17 of 19
Gearbox
At regular intervals, visually inspect gearbox for oil loss and replenish if necessary (refer to
DER05023). To perform the inspection, shut down, lockout, and tag out centrifuge, remove belt
guard, and open case cover. The likely sources of leakage are the input shaft seal and areas
around solids discharge openings of the drum. If oil leakage is found, the gearbox must be
removed and overhauled. This procedure must be performed only by trained, qualified personnel
who are experienced in gearbox repair and overhaul.
Drive Belt Tension
Drive belt tension should be checked at regular intervals (see DER05023).
Alarm and Fault Messages
During centrifuge operation, a message may appear to alert the operator to an anomaly that
requires operator intervention. Alarm messages signify that the prevailing condition must be
corrected or the centrifuge may be shut down automatically. Fault messages inform the operator
that a failure requiring automatic shutdown has occurred.
Refer to
DER05105 - Troubleshooting for alarm messages and their causes and corrective
actions.
CLEAN OUT PROCEDURE
If automatic reduction of the pump speed is unable to clear out solids from the conveyor, the
torque will continue to rise and the centrifuge will shut down. The clean out procedure should then
be used to clear out the impacted solids and return the centrifuge to operational status. The
following paragraphs explain the two cleanout options: automatic and manual.
Automatic Cleanout
When the automatic option is selected (Figure 4098-3), the system will perform a cleanout cycle
for a pre-set duration. The bowl operates in the forward direction at the set speed, while the
conveyor operates in the forward direction at a speed that varies from 4 to 30 RPM. If resistance
is encountered during the cleanout, the motors will stop and the cleanout cycle will be repeated.
Following a pre-set number of cleanout attempts, the system will pause and alert the operator that
the automatic cleanout has been unable to clear the centrifuge. Operator intervention is then
required to repeat the automatic cleanout operation. The operator is also alerted if excessive
conveyor torque occurs during the cleanout procedure.
Manual Cleanout
If the manual cleanout option is selected, the operator may elect to jog the conveyor in forward
and reverse with the bowl set at zero RPM. If desired, however, the operator may choose to
operate the bowl as well as the conveyor. Reverse rotation of the conveyor is governed by a timer
that terminates reverse operation after a pre-set interval. The primary purpose of the manual
cleanout mode is to permit jogging the conveyor in an effort to remove impacted material.