1. Centrifugal tube making process
When plastic concrete is used, the wall structure of the pipe is layered after molding, which affects the ability of the concrete to resist the load. The general designation of the concrete is C30, which can also achieve C40, but the concrete weight of the pipe mouth is lower than the pipe body, which is not suitable for Pipe jacking; When the pipe mold is lying on the centrifuge at high speed during molding, the steel mesh moves with it, which will show two situations that affect the service life of the pipe: 1. The steel mesh will show running and leaking ribs when the welding joints are not connected. Phenomenon makes the tube part appear no-reinforced. 2. It is difficult to center the reinforced mesh after forming. The reinforced mesh is a pain, that is, the protective layer of the reinforced mesh is uneven. This process requires a lot of molds to ensure the output. There is an error in the size of the mold. The long-term disassembly and use of the open mold will also show a large deformation, which results in large errors such as the roundness of the pipe, the straightness of the mouth, the diameter of the pipe, and the length of the pipe. The quality of the installation of the project, showing that the leakage will cause the road surface to sink and pollute the soil and groundwater on both sides of the pipeline;
Second, the suspension roll pipe making process
Dry and hard concrete is used, the concrete structure of the pipe wall is uniform, and the ability to resist loads is outstanding; the concrete designation is generally C30, C40; the noise during molding is reduced compared to the centrifugal process, and the operating site environment is cleaner than the centrifugal process; the defect is to be small When the diameter of the pipe is added, the wall thickness must be added to meet the impermeability requirements; some other defects of the centrifugal process are also the same as the suspension roll process;
Third, the core mode oscillation process (internal mode oscillation process)
This process selects semi-dry rigid concrete, the vertical cloth inner mold oscillates and kneads in the radial direction. After molding, the inner mold oscillating force and amplitude are adjusted to compact the concrete with the best oscillating force, so as to obtain a C50 high-strength pipe. Concrete, which makes the pipeline's anti-load ability and anti-seepage function significantly enhanced compared with centrifugal and suspension roll processes. At the same time, the stern tube reinforced mesh protection layer of this process is uniform, and the phenomenon of centrifugal and suspension roll process reinforcement mesh displacement, jump bars, parallel bars, and loose bars will not appear, which guarantees the service life of the pipe for 50 years. Because the vertical core mold oscillating tube manufacturing process uses two overall tube molds on the front and the back, the mold rigidity is very good and it is not easy to deform, and only one set of mold is required for one specification, so the roundness and diameter of the shaped stern tube are standardized. The tube body has no closing seam, and the finish of the inner wall of the tube is significantly improved compared with the centrifugal process and the suspension roll process. In addition, the vertical core-mold oscillating pipe making process rotates and kneads the concrete again in the axial direction after the concrete is fed, which more effectively adds the strength and straightness of the nozzle, and the construction device is smooth.