The belting on a conveyor installation is one of the highest capital and replacement cost items and as such, the life of the belt should be maximized.
Belt life expectancy depends on the operating conditions, the length of the belt, level of maintenance, etc. however it is not unusual to expect a belt to have a life of up to 20 years on long conveyors (greater than 2km) and 5 to 8 years on shorter conveyors.
By conducting frequent inspections and preventative maintenance, the user can extend the life of the belt considerably.
Primarily the inspections and maintenance regime put in place should ensure that at least the following aspects are addressed.
a) Belt care
The belt should be visually inspected periodically for :-
Cuts in the top cover. If these are not serious, they should be monitored and propagation of such damage must be addressed / repaired.
Gouges in the covers.
Where localized sections of the cover have peeled off or are loose.
Damage to the edges of the belt such as cuts, gouges and abrasion. This is an indication that the belt may not be running aligned under all operating conditions.
Any damage which results in the carcass or cables being exposed.
The frequency of these inspections must be determined by the user. By monitoring the cumulative number of operating hours and the load carried by the belt, the user should be able to initiate an inspection policy combined with a maintenance regime.
Conveyor monitoring techniques are outlined in "Accessories" of this Handbook.
b) Belt repair procedures
The following belt repair procedures are recommended for the most common types of belt damage :-
Minor Cuts and Gouges
Minor cuts and gouges in covers or edges which penetrate to the carcass or cables should be repaired before the affected area spreads.
This damage can be repaired by inserting doughs, by cold vulcanizing patches or by hot vulcanization of the localized damage.
The time available to perform the repair often dictates the type of repair. Hot vulcanization is usually the most effective and longest lasting repair.
Splice damage, significant areas of cover failure / damage, torn-off edges and so on constitute 'major damage' to a belt.
In these cases the belt should be taken out of service and repairs carried out immediately.
If it is impossible to de-commission the conveyor immediately, emergency repairs should be performed using doughs, cold vulcanization or even hot vulcanization.
Loose edges of the belt which may be partially detached from the belt, should be cut off to prevent further tearing and damage to the surrounding structures as the belt moves.
The conveyor must however be removed from service as soon as possible in order to perform a permanent repair.
In the event that a severe longitudinal cut has developed in the belt, it may be necessary to cut out a section of the belt and replace it with a new length of belt which must be spliced into the 'old' belt. For such repairs, consult the "splicing" section of this Handbook.