Centrifugal Tube Manufacturing
The use of plastic concrete results in a layered wall structure after molding, which affects the concrete's load-bearing capacity; the concrete grade is typically C30, but can also reach C40, however, the concrete strength at the pipe mouth is lower than that of the pipe body, making it unsuitable for jacking pipes; during molding, the pipe mold lies horizontally on a centrifugal machine and rotates at high speed, causing the steel mesh to move, leading to two situations that can impact the service life of the pipe material:
1. When the welding points on the steel mesh are not sturdy, it can lead to the occurrence of deformed steel bars and exposed steel bars, resulting in localized areas of the pipe body with no reinforcement.
2. After forming, the steel mesh is difficult to center, and the steel mesh is eccentric, meaning the protective layer of the steel mesh is uneven. This process requires a large number of molds to increase yield, and each mold has dimensional discrepancies. Over time, the continuous disassembly and assembly of open molds also leads to significant deformation. This results in considerable deviations in the roundness of pipes, the perpendicularity of pipe ends, the diameter size, and the length size of pipes, which affects the installation quality of the project. Leakage may cause the road surface to sink, and pollute the soil and groundwater on both sides of the pipeline.
Cold Rolling Pipe Mill
The concrete used in the pipeline walls is of a dry, rigid consistency, ensuring uniform structure and good load-bearing capacity; the concrete grade is typically C30 or C40; the noise during molding is reduced compared to the centrifugal process, and the operating site is cleaner; however, to meet the impermeability requirements for small-diameter pipes, the wall thickness needs to be increased; some other drawbacks of the centrifugal process are also present in the suspended roller process.
Chip Molding Vibration
This process utilizes semi-dry, rigid concrete, with vertical material distribution and radial extrusion molding. During the molding process, by adjusting the vibration force and amplitude of the inner mold, the concrete is compacted with optimal vibration force, resulting in C50 high-strength concrete pipe bodies. This significantly enhances the pipeline's load-bearing capacity and water resistance compared to centrifugal and suspended roller processes. Additionally, the concrete pipe's steel mesh protective layer is uniform, eliminating the issues of steel mesh displacement, uneven spacing, overlapping, and scattered reinforcement observed in centrifugal and suspended roller processes, thereby extending the service life of the pipe materials to 50 years.
Due to the use of two integral pipe molds, both internal and external, in the vertical core mold vibration tube-making process, the mold's rigidity is excellent and it is not prone to deformation. Additionally, a single specification requires only one set of molds, ensuring that the concrete pipe has standard roundness and diameter sizes, with no seam along the body. The inner wall smoothness has been significantly improved compared to the centrifugal and suspended roller processes. Moreover, after the concrete feeding is completed, the vertical core mold vibration tube-making process performs a rotational compression in the axial direction, effectively enhancing the strength and verticality of the pipe mouth, making construction and installation smooth.