Full definition
A vulcanized splice is regarded as the strongest and most durable method for joining the ends of conveyor belts. This technique utilizes a combination of heat, pressure, and specialized splice rubber or adhesives to create a chemically bonded joint that is virtually seamless. The process typically involves heating the splice area to temperatures between 145-160°C and applying pressure in the range of 5-15 bar. This results in a bond that can achieve 90-100% of the original breaking strength of the belt, making it suitable for heavy-duty applications in various industries such as mining, construction, and material handling.
For textile belts, the vulcanized splice is often performed using a stepped (or finger) splice technique. In this method, the plies of the belt are stripped back at calculated lengths, interleaved, and then vulcanized together. This design maximizes the strength of the bond by ensuring a gradual transition of load across the joint. Conversely, for steel cord belts, a cable overlap splice is employed where individual steel cables are laid out in a specific pattern with predetermined overlap lengths, following ISO 15236 standards. This method ensures that the mechanical strength of the splice is aligned with the overall structural integrity of the belt.
The equipment required for creating a vulcanized splice includes a portable vulcanizing press, which can be either electric or steam-heated, along with C-frames or water-cooled platens that provide the necessary pressure during the vulcanization process. The temperature must be precisely controlled throughout the cycle, which involves heating the splice for 20-45 minutes depending on the belt thickness and then cooling it under pressure to below 60°C. The total time for completing a vulcanized splice, including preparation, can range from 4 to 8 hours. Given the complexity of this process, it is essential to have trained technicians performing the splice and to account for a significant investment in equipment to ensure quality and reliability.
The vulcanized splice is recognized as the gold standard for creating permanent, high-performance joints in conveyor belts, ensuring operational efficiency and minimizing downtime in industrial applications.