Conveyor belts typically incur damage to their covers, fabrics and carcasses. Covers acquire rips, tears, cuts, gouges and scoring. Carcasses become worn and punctured. Belts fracture and fray at the edges.
Conveyor belt repairs can take operations offline for a significant period of time. Using hot vulcanising or cold vulcanising methods to repair a conveyor belt can greatly reduce the amount of time your system is down. Additionally, repairs using either of these methods can extend the life of your conveyor belt system.
There are three kinds of conveyor belts namely:
* Nylon fabric conveyor belts
* ST steel cord conveyor belts
* Flame-retardant PVC whole core conveyor belts or solid woven PVC belts
Vulcanised splices typically deteriorate from the inside out due to poor adhesion and signs of wear may come too late for any preventive measure. However, a vulcanised belt joint will nearly always outlive a mechanical splice. The process requires unique tools and an intimate knowledge of the rubber bonding process.
Cold vulcanising method
The cold vulcanising method employs vulcanised material such as patches and strips to repair a conveyor belt. Cold vulcanisation does not use a press, but uses a bonding agent like Chemvulc’s CV2002 or CV4000, that causes a chemical reaction to splice the two belt ends together. The vulcanised material is placed over the damaged area and secured with an adhesive. This makes the cold vulcanising method ideal for repairing belt covers damaged by scoring, gouges and other types of wear. See Chemvulc’s range of repair strips and cold repair patches for conveyor belts.
Hot vulcanising method
The hot vulcanising method utilises heat and pressure to mend sections of a conveyor belt. Hot vulcanisation splices are heated and cured under pressure with a vulcanising press. The damaged portion of belt is carefully trimmed or removed. A new section repaired and bonded in place using cement or other adhesives. The hot vulcanising method is optimal for holes, cuts and tears in belt covers, steel cords and fabric.
Vulcanised splices have the highest practical strength as a vulcanised joint will prevent any leakage and material sift-through as the joint is continuous. You can’t vulcanise anytime, anywhere – you need clean, dry and relatively warm conditions. Although on site, this always isn’t possible – sometimes the area needs to be covered from rain or excessive sun, while the splice is being prepared.
Hot and cold splicing of belts require meticulous preparation to prevent contamination of the splicing area. Cold splicing requires relatively warm conditions and low moisture to ensure the cold vulcanising cements work optimally.
Vulcanised splices typically deteriorate from the inside out due to poor adhesion, and signs of wear may come too late for any preventive measure. However, a vulcanised belt joint will nearly always outlive a mechanical splice.
Sources: Almex, Conveya, Chemvulc