This procedure provides some general information in training guide form for checking the tracking of the belting on a typical belt conveyor. It is not all-inclusive, and the user of this procedure must use common sense when confronted with a specific belt conveyor that may not exactly fit the instructions in this procedure.
Conveyor belts that run off-center are a common and potentially costly problem in mills. Running off-track can cause edge wear or other damage to the belts themselves; damage to other components of the system, such as idlers and pulleys; and possibly spillage of materials being moved through the plant.
Correctly training a conveyor system prevents this costly wear and tear and other more serious damage to the system components. The adjustments should also contribute to making the workplace safer by preventing materials spillage. The relatively short time it takes to train a conveyor may save substantial downtime.
Conveyor belts do not track properly for several reasons, including the following:
Pulleys and/or idlers are not squared.
A new belt has not “run in” long enough.
There is uneven loading. The loading is off-center, normally at the feed end of the belt.
The conveyor structure or frame is not square.
The belt lacing or splice is not square.
There is a bow in the belt.
In order to determine if there is a problem with a conveyor belt not tracking properly, it must be observed while in operation. While keeping a safe distance from the conveyor, the mechanic must observe how the belt tracks across the head pulley, tail pulley, and the idlers.
Never attempt to come in physical contact with a conveyor belt that is operating.
SAFE JOB PRACTICES
Precautions and Personal Protective Equipment
Precautions
Always be aware of rotating equipment when it is in operation; loose clothing or parts of the body such as a hand, arm, foot, or leg could be pulled into the machine causing severe injury or death. Also, be aware that rotating equipment that is not operating can be on standby and can start at any time.
Do not get too close to rotating equipment unless you have shut it down and have locked and tagged out the unit.
Ensure that mill operation personnel are aware that you are in the area. Let operations know when you leave the area.
Personal Protective Equipment
Always wear the company-mandated personnel protective equipment (PPE), such as hardhat, steel-toe shoes or boots, safety glasses with side shields, and ear plugs where required. Additionally, in some areas where dust or chemicals are present, an approved respirator must be worn.
EQUIPMENT/SPECIAL TOOLS REQUIRED
Mechanic's measuring tape.
Common mechanic tools.
MATERIALS/CONSUMABLES REQUIRED
None.
PROCEDURE
Inform operations personnel that you are in the area.
Ensure that the conveyor belt is in operation.
Station yourself at the tail pulley, directly in the middle.
If the tail pulley safety guard is such that you do not have an unobstructed view of both the tail pulley and the belt tracking over it, the guard will have to be removed using common mechanic tools.
If removing the safety guard from the tail pulley presents a safety hazard, then operations personnel need to shut down the conveyor belt before the safety guard is removed.
With the conveyor operating, observe the belt tracking over the tail pulley for at least three full revolutions.
If the belt is not tracking in the middle of the tail pulley, then the tracking will need to be adjusted. Refer to Adjusting Conveyor Belt Tracking, for specific instructions before proceeding with the rest of this procedure.
If the belt is tracking over the center of the tail pulley, proceed with this procedure.
If the tail pulley safety guard was removed, it must now be reinstalled and securely fastened.
If necessary, request that operations personnel stop the conveyor while the safety guard is reinstalled.
Walk the full length of the operating conveyor belt, noticing the tracking along the way.
If the belt is not tracking properly along the conveyor, some material-carrying idlers need to be adjusted. Refer to Adjusting Conveyor Belt Tracking, for specific instructions before proceeding with the rest of this procedure.
If the belt is tracking properly along the conveyor, proceed with this procedure.
With the conveyor operating, observe the belt tracking over the head pulley for at least three full revolutions.
If the belt is not tracking in the middle of the head pulley, then the tracking needs to be adjusted. Refer to Adjusting Conveyor Belt Tracking, for specific instructions before proceeding with the rest of this procedure.
If the belt is tracking over the center of the head pulley, proceed with this procedure.
Contact operations personnel in the area and let them know that you are leaving the area.