At present, the tension material of belts used in the industrial conveying and transmission field is mostly made of polyamide (nylon) sheets. The disadvantages are high hardness of the belt body, large wheel diameter, and large tensile deformation. The belt body is greatly affected by temperature and humidity, and is prone to bending deformation.
Another common type of transmission belt in the transmission belt industry is made of polyester as the tension material, which is TC-belt. The conventional TC-Belt consists of five layers, from top to bottom: upper rubber transmission layer, upper polyester buffer layer, middle polyester tension layer, lower polyester buffer layer, and lower rubber friction layer. Due to the use of a polyester fiber instead of a nylon tension layer, the tension shape of the TC-Belt is reduced, and its size and appearance are more stable.
The polyester belt uses thermoplastic elastomer polyester as a buffer layer. Thermoplastic elastomer materials are usually selected with a hardness of 95a, which has high mechanical strength and can meet the mild needs of high-speed operation of TC-Belt. When connecting a polyester belt to a circular belt, first use a toothed machine to treat the two ends of the belt body into a serrated shape that can be seamlessly docked, with a tooth length of generally 90mm. The spliced toothed joint is subjected to a high temperature of 165 ° C, a pressure of 2mpa, and a time of 3 minutes. It is then cooled to room temperature after cooling treatment.
Because the polyester sheet material at the joint must undergo a high temperature treatment of 165 ℃ during connection, and the mechanical properties of the polyester material after high temperature treatment and cooling significantly decrease, and it has a certain degree of brittleness and hardness, which leads to the joint becoming a "weak" point in the mechanical properties of the entire belt body. During repeated high-speed operation, it is easy to fracture. It was also found in tracking customer information about the use of the TC-belt, 95% of the polyester belt cannot be used anymore due to a broken joint.
So, the key factor limiting the service life of the TC-Belt is the strength and mechanical properties at the joint. Therefore, GC has been working on improving the structural composition of the TC-Belt, so that when it forms a circular belt, the strength at the joint is better to meet the needs of use.