Full definition
Belt vulcanization is a critical process used in the maintenance and repair of conveyor belts, particularly in industries such as mining, manufacturing, and logistics. This method involves creating a robust chemical bond between the ends of a conveyor belt by utilizing heat, pressure, and specific vulcanizing agents. The result is a splice that can achieve 90-100% of the original belt's breaking strength, making it a preferred choice for ensuring long-lasting performance. The process begins with the preparation of the belt ends, which may involve stripping the cover rubber and arranging the belt's internal structure—either textile layers or steel cords—according to calculated overlap lengths. This precision is essential for ensuring a strong and reliable splice.
Once the belt ends are prepared, a series of bonding agents, including conditioners, primers, and rubber cement, are applied to all surfaces that will be joined. Following this, splice rubber, which consists of cover, skim, and breaker fabric materials, is laid in place. The vulcanizing press is then closed, applying pressure at a range of 5-15 bar. The temperature is carefully controlled during this phase—145-155°C for textile belts and 140-145°C for steel cord belts. This heating phase typically lasts between 20 to 45 minutes, depending on the thickness of the belt being spliced.
Cooling the splice is just as crucial as heating; the splice must cool under pressure to below 60°C before being released from the press. The total elapsed time for the entire vulcanization process can range from 4 to 12 hours, heavily influenced by the size of the belt and the cooling method employed in the press. Adhering to industry standards, such as ISO 15236 for steel cord splices and DIN 22102 for textile splices, as well as the specifications set forth by manufacturers like Rema Tip Top and Almex, is essential to ensure quality and safety. Only trained and certified technicians should perform this process to guarantee the integrity of the splice and the overall performance of the conveyor system.