The conveyor belt of the circular tube belt conveyor is surrounded by a set of regular polygon rollers and forced into a circular tube shape, which can be spatially bent to arrange the route. Therefore, compared with ordinary belt conveyors, there are still many issues that need to be discussed and studied.
1、The length of the transition section and the arrangement of its rollers
     The length of the transition section at the head and tail of the circular tube belt conveyor is determined by the diameter and type of the conveyor belt, as well as the allowable elongation of the conveyor belt. If the transition section is too short, the edge of the conveyor belt will generate significant additional tension, causing it to suffer from fatigue damage due to excessive drought, and in severe cases, the edge may tear; If the length of the transition section is too long, it will reduce the sealing length of the entire conveyor line. For fabric core conveyor belts, the transition section L passes through ≥ 25D tubes; For steel cord conveyor belts, the transition section length L should be greater than or equal to 50D pipe. The transition section length and minimum conveying distance of the circular tube belt conveyor.
Arrangement of the tail transition roller group. The spacing between buffer rollers is generally 300-500mm, and they are all groove shaped rollers. When the particle size of the conveyed material is large, the material on the conveyor belt should be intentionally shaken up and down in the transition section, and the circular tube conveyor belt should be pushed from both sides to make the longitudinal direction of the material block consistent with the running direction of the circular tube conveyor belt, so as to smoothly enter the circular tube conveyor belt. Pushing the conveyor belt is achieved by setting vertically staggered rollers on both sides of the conveyor belt in the transition section, but it is also necessary to prevent the conveyor belt from being pushed out in the left and right directions (deviating). When the length and diameter of the conveyed material are greater than the nominal diameter of the circular pipe conveyor belt, the filling coefficient should be adjusted or the nominal diameter of the circular pipe conveyor belt should be increased. At this time, the belt speed should be re matched to ensure that the required conveying capacity is achieved. The transition section of the head of the circular tube conveyor belt sometimes requires the installation of a pressure roller.
2、Space bending arrangement and curvature radius
    The significant feature of the circular tube belt conveyor over the general belt conveyor is that it can make smaller radius turns, thereby reducing the external contour. When the general belt conveyor cannot be used in the layout of the conveyor line or multiple transfer points are required, the circular tube belt conveyor can be selected.
Due to the fact that the conveyor belt of the circular tube belt conveyor is completely constrained by the surrounding rollers, there is no deviation phenomenon compared to the general belt conveyor. The circular tube belt conveyor can bend in both vertical and horizontal planes, or bend in both planes at the same time, eliminating the need for transfer points. It can pass through existing obstacles such as factory equipment from the side, top, or bottom, and can cross obstacles or other facilities, thus eliminating intermediate transfer and achieving the goal of transporting materials on long and complex routes with a conveyor. The circular tube belt conveyor can also be installed on soft ground and the conveyor line can be conveniently arranged according to actual needs. The conveyor belt can start bending as soon as it forms a circular tube through the transition section, and the bending must be completed before reaching the transition section of the discharge drum. The transition section at both ends of the conveyor must be straight.
      Circular tube belt conveyors are not suitable for situations where there are feeding and unloading points in the middle. If it is necessary to set up a feeding or unloading point in the middle of the conveying section, it is generally done by adding a transition section to flatten the conveyor belt, and installing a feeding device at the feeding point for feeding; Alternatively, electric or manual plow type unloaders can be used for direct unloading in the unloading area, with unloading methods divided into single-sided and double-sided.
     When there are many curved sections, it is best to arrange the number and direction of curved sections symmetrically on both sides of the conveyor to ensure that the tension of the conveyor belt is evenly distributed on its cross-section during operation and reduce distortion.
      The curvature radius of a curved arrangement is usually determined by factors such as the diameter of the conveyor belt, the type of conveyor belt, and its usage. The size of the curvature radius affects the maximum tension of the conveyor belt and directly affects the service life of the conveyor belt and rollers. Therefore, if the on-site layout conditions permit, or at locations where the tension of the conveyor belt is high, the bending radius should be increased. General standard minimum bending radius: When bending horizontally or in a concave arc, weave ≥ 300d tubes for fabric core conveyor belts and ≥ 700d tubes for steel wire rope core conveyor belts; When S-shaped, convex arc bending, or a combination of horizontal and concave arc bending occur, weave ≥ 400d tubes for fabric core conveyor belts and ≥ 800d tubes for steel wire rope core conveyor belts; When horizontal bending and convex arc coexist, weave ≥ 500d tubes for fabric core conveyor belt R and ≥ 900d tubes for steel wire rope core conveyor belt R; If the diameter configuration of the steel wire rope is reasonable, the curvature radius of the steel wire rope core conveyor belt can be 600d pipe.(Selected from the internet)