20 years of self-extinguishing steel-cord conveyor belts in deep coal mining.

These betls were first installed in Germany in 1976. The main characteristics of self-extinguishing belts of this type are the use of a completely new material grade, open rubberised cord construction, textile transverse reinforcement and the use of a bonding system with high dynamic strength. The use of polychlorobutadiene for the steel cords resulted from the introduction of inceasingly stringent flammability specifications. The long-term ageing characteristics of the belts are established under laboratory conditions and there are also regulations for the tear resistance and elongation of the covers and the cord pull-out strength. Factors which affect the service life of the conveyors include operating load and planned service life of the covers, inclusion of a corrosion-resistant reinforcement system, use of open cord construction, a galvanisation layer of appropriate thickness, use of a bonding rubber which is dynamically competent and has a high thermal resistance and high cohesive strength between the belt components.
These betls were first installed in Germany in 1976. The main characteristics of self-extinguishing belts of this type are the use of a completely new material grade, open rubberised cord construction, textile transverse reinforcement and the use of a bonding system with high dynamic strength. The use of polychlorobutadiene for the steel cords resulted from the introduction of inceasingly stringent flammability specifications. The long-term ageing characteristics of the belts are established under laboratory conditions and there are also regulations for the tear resistance and elongation of the covers and the cord pull-out strength. Factors which affect the service life of the conveyors include operating load and planned service life of the covers, inclusion of a corrosion-resistant reinforcement system, use of open cord construction, a galvanisation layer of appropriate thickness, use of a bonding rubber which is dynamically competent and has a high thermal resistance and high cohesive strength between the belt components.