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Conveyor belts commonly used include canvas belts, vinylon belts, and nylon belts; they are employed at normal temperatures for transporting various non-corrosive bulk, granular, and powdered materials such as coal, coke, sand, and gravel. Ordinary conveyor belts are typically made 100 meters long; when the length of the belt used in a belt conveyor exceeds 100 meters, more joints need to be added ； When the conveyor belt of another belt conveyor wears out and the damaged section needs to be replaced, a joint is also required. The load-carrying capacity and service life of the conveyor belt on a belt conveyor are closely related to the quality of the joints; good-quality joints result in a higher load-carrying capacity and a longer service life. The price of belt conveyor belts is around 400 yuan per meter. Extending the service life of these belts can help reduce the costs associated with conveyor systems; therefore, it is very important to handle the joints of belt conveyor belts properly. 1. The common method for mechanical jointing of conveyor belts in belt conveyors is hook and clip connection. The fastening belt buckle for hook-and-clasp connections is multi-clawed; a hammer is used to wedge the claws into the end of the belt, and after inserting the pin, it is ready. For conveyor belts of different thicknesses, different types of belt buckles that are suitable for them should be used. With this type of jointing method, the strength is significantly reduced; the strength after clamping is only 35% to 40% of the belt’s own strength. It is generally not chosen, and is mostly used as an emergency measure. 2. The hot adhesive vulcanization method for belt conveyors involves cutting the fabric layer and rubber layer in the joint area of the conveyor belt into symmetric sections in a specific manner, applying adhesive to bond them together, and then heating them under certain pressure and temperature conditions for a specified period of time. Through the vulcanization reaction, the raw rubber transforms into vulcanized rubber, thereby achieving a higher level of adhesion strength at the joint area. The joint strength obtained using this method can reach 85% to 90% of that of the original conveyor belt. Although this type of joint has high strength, its technical requirements are difficult to master; accurately understanding these requirements is key to ensuring the joint’s strength and lifespan. Inadequate or improper control of the sulfurization process conditions can lead to quality defects such as under-sulfurization, over-sulfurization, delamination, bubbling, skin peeling, and visible scars. Furthermore, the vulcanization equipment is rather bulky and difficult to transport. 3. The cold adhesive vulcanization method after process improvement for belt conveyors’ belts: This method is carried out at room temperature and requires simple tools, which greatly facilitates on-site construction. After process improvement, the physical and mechanical properties as well as service life of the joints can reach the same level as those of the hot adhesive bonding method. (1) The primary steps for handling belt joints in belt conveyors include cutting, creating steps, peeling off the steps, aligning the edges, and grinding. Whether the conveyor belt joints can align properly has a direct impact on its performance; therefore, it is necessary to determine the center line of the belt joints before making any cuts, so as to ensure that the center lines coincide when the belts are joined together. Joint processing procedure: ① Cut the conveyor belt of the belt conveyor. The interface is cut at an angle of α=30° to 60° relative to the centerline of the tape, so that it is not easily picked up by the cleaner; generally, α=45° is used. ②The conveyor belt of the belt conveyor is stepped. The cut tape ends are divided into several steps of equal size; generally, the number of steps equals the number of layers of the tape fabric minus 1. The width of each step along the centerline is between 150 and 200 mm, with 40 to 60 mm left uncut at each end of the conveyor belt to protect the joint. ③Peeling steps on the belt of the belt conveyor. First, peel off the last step (considering the step at the end of the conveyor belt as the first one). When cutting, use gentle pressure – only cut through one layer of canvas, without damaging the underlying layer. Then, tear off the adhesive layer on the working surface together with the first layer of canvas, but leave 40–60 mm uncut and unpeeled at both ends of the conveyor belt. Peel off each step in sequence following the above process; it is necessary to leave one layer of canvas and the adhesive layer on the working surface for the first step. ④Alignment adjustment of the conveyor belt on the belt conveyor. Align the center lines of the two stripped adhesive strips and bring them together; check the gap at the joint to ensure that it is tight, with a gap of no more than 1 mm. If this is not the case, make appropriate adjustments to ensure good adhesion quality. ⑤Polishing of belt conveyor belts. Use a hand-held wire wheel grinder or a carpenter’s file to remove any remaining rubber from each step, being careful not to damage the canvas layer. (2) For the joints of the belt conveyor belts that have been treated with glue, glue can be applied once the canvas is transparent; generally, 3 applications are made. The glue mixture for the first application is slightly thinner (solute: solvent = 1:6), while that used for the second and third applications is slightly thicker (solute: solvent = 1:3–4). The glue should be applied evenly; it shouldn’t be too thick. It is necessary to wait until the glue applied in the previous application has fully evaporated and the surface becomes transparent (so that it does not stick to the hands) before applying another layer. (3) After the adhesive from the third application of the sealing brush for the belt joints of the belt conveyor has dried, the two ends can be brought together. Starting from one end of the joint, glue from the center toward the sides to facilitate air drainage to both sides. It is necessary to ensure that the stepped bonding orientation of the joint is correct. Once it is closed, it is difficult to separate; even if separated, it will affect the quality of the adhesive bond. After closing, apply repair mortar at the joint where the upper and lower layers are bonded; the width should be 3–5 mm and the height 0.5–1 mm. (4) For the joints of the belt conveyor belt, after rolling and pressing them together, these joints can be compacted by using a hammer, striking from the center outwards. Then, use two 15mm thick steel plates to firmly press the joint in place. Due to the large width of the steel plate, its center may warp, resulting in a weak joint; this can be addressed by using channel steel or bolts for clamping. Depending on the quality of the glue, after a few hours, the conveyor belt can operate under heavy load. Joints created using this cutting method show virtually no signs of cutting on the working and non-working surfaces of the belt conveyor belt, as well as at both ends of the belt. This approach effectively prevents the canvas layer from deteriorating due to moisture intrusion, thereby extending the service life of the conveyor belt.