Page 15 - ConveyorBeltMaintenanceManual2010

SEQUENCE OF TRAINING OPERATIONS
Initial installation of conveyor equipment should ensure good alignment of all pulleys, troughing idlers and return
idlers; that is, they should be placed at right angles to the direction of belt travel and should be leveled and centered
on a straight line. First movement of the belt should be slow and intermittent so that any tendency of the belt to run
off can be quickly observed and the belt stopped before damage occurs.
When the conveyor is a long center installation, men should be stationed at frequent intervals to observe the action
of the belt. They should be provided with an effective method of communication so they can report their observations
and if necessary, stop the belt.
Initial movement of the belt will indicate where corrections of the types described are required. The first corrections
must be at points where the belt is in danger of being damaged. Once the belt is clear of all danger points, a sequence
of training operations can be followed. Since the training will finally complete a circuit, just as the belt does, there is
no point at which training can be started without the possibility of having to make subsequent corrections when
returning to the starting point as the circuit is completed. The best procedure appears to be in starting with the return
run and working toward the tail pulley. This ensures early centering of the belt on the tail pulley so that it can receive
its load centrally, which is highly important.
If the belt is readily troughable so that its running tendencies are not erratic, the training can and should be completed
on the empty belt. Should it tend toward stiffness and erratic running, getting some load onto the belt as soon as the
return run has been straightened up and the belt is centered on the tail pulley will help hold the top run.
Normally, the belt can be trained properly onto the tail pulley by manipulation of return idlers and with the assistance
of self-aligning return rolls. Seldom is any adjustment of snub or tail pulley necessary, but the snub can be used in
supplementary training.
Training of the top run, with the belt empty, is usually no problem if the belt is readily troughable. In this case, self-
aligners on top are not required, except as insurance in the region approaching the head pulley. There, two self-
aligners placed approximately 40 and 80 feet preceding the pulley will help re-center the belt if it is forced off due to
some temporary disturbance.
It should not be necessary to use the head pulley for training purposes if it has been aligned properly. Likewise, the
snub following the head pulley should not be required as a training means, since it is relatively ineffective in its
position following the strong head pulley influence.
The take-up carriage has a strong influence on the running of the belt at that point, and due to its movement as belt
length changes, is subject to misalignment. A vertical take-up carriage, hanging in a festoon of belt, must be guided
in its travel so that the pulley shaft remains horizontal. The belt cannot be depended upon to center itself on the
pulley. Once it becomes off-center, the pulley will tip out of horizontal if not guided closely on its posts.
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INSTALLATION, MAINTENANCE & TROUBLESHOOTING GUIDE
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