I. Product Introduction:
Fiberglass Reinforced Plastic (FRP) pipe is a newly developed pipeline product in the drainage and water supply field. It allows for underground pipeline construction and installation without excavating the ground. This pipe can directly cross over highways, railways, rivers, and ground structures. Thanks to its excellent corrosion resistance, lightweight, smooth inner wall, high flow rate, and good adaptability to geological conditions, it has become a preferred pipeline material for large and medium-sized urban pipeline projects.
Section II: Product Features:
1. Lightweight (1/10th the weight of concrete pipes), with low foundation requirements, minimal demands for lifting and pipe-laying equipment, and easy construction.
2. Due to reasons such as minimal settlement and low uplift, pipe alignment correction is easy.
3. Smooth inner wall, high flow rate; under a fixed flow rate, a smaller pipe diameter can be used, which can reduce the overall engineering cost.
4. Smooth surface, low thrust, soil cohesion has minimal effect on the glass fiber reinforced pipe's top, no抱管or dead pipe phenomena, long single push-in length, low requirements for push-in equipment.
Section 3: Process Route
Utilizing a 12-meter long fixed-length winding process for reinforced glass fiber composite sand-filled pipes, four 3-meter-long pipe sections are produced on each mold in a staggered manner according to the design layers. The ends of each pipe section, ranging from 300 to 800mm of pure glass fiber composite, are locally reinforced with glass fiber fabric. The sections are milled and cut using special equipment, and after trimming to the specified shape and size, they can be demolded in one go. The production efficiency fully meets the project progress requirements. A design and production process that integrates pure glass fiber composite and glass fiber reinforced sand-filled composite reinforcement is adopted.
Section 4: Design Technology
Based on the specific application conditions of glass fiber reinforced plastic (FRP) sand-filled pipe in the jacking pipeline project, determine design parameters such as pipe diameter, material stiffness grade, soil parameters, design load (including internal pressure, vacuum, vertical static soil pressure on the pipe crown, live load from ground vehicles, and soil heap load), etc. These parameters provide a theoretical basis for the structural calculation of the FRP sand-filled pipe.
V. Structural Calculation:
Based on the selected design conditions and parameters, the structural calculations for the glass fiber reinforced plastic manhole cover pipe are conducted in accordance with China's national standard "Glass Fiber Reinforced Plastic Manhole Cover Pipe" (GB/T 21492-2008), "Manhole Cover Pipe Construction Technology," and computer nonlinear finite element numerical calculations. The structural calculations of the pipe material include calculations, analyses, and checks for thrust strength, stiffness, bending deformation, bending strength, stability analysis, seismic strength analysis, and more.
Section 6: Production Process
1. Confirm and approve the design and production plan.
2. Lining manufacturing
3. Glass fiber hoop and cross-woven internal structure layers.
4. Use special sand-blasted fabric with intermittent sandblasting (the sandblasted fabric is continuous on pure fiberglass but stops at the sanding point).
5. After each layer of sanding, promptly fabricate the pure fiberglass sections.
6. Glass fiber hoop and cross-wound outer structural layer
7. Trim and cut to achieve uniform shape and specified dimensions.
8. After demolding, the products are inspected and then fitted with steel rings before being shipped out.
Section 7: Connection Method:
The pipe sections are connected and positioned using embedded steel sleeve rings. During pushing, glass fiber reinforced plastic resin is used for sealing. After the two pipes are joined, they serve as a water seal. A platform is machined at both ends of the pipe to ensure that the outer diameter of the steel sleeve ring matches the pipe's outer diameter after it is fitted over the pipe end. The steel sleeve ring serves as a positioning device and enhances resistance to uneven settlement. The resin mouth provides sealing, and the two pipes act as a water seal upon joining. A platform is machined at both ends of the pipe to ensure that the outer diameter of the steel sleeve ring matches the pipe's outer diameter after fitting, serving as a positioning device and improving resistance to uneven settlement.
Section 8: Applicable Locations:
● Water supply and municipal engineering. ● Petroleum and chemical engineering. ● Construction engineering. ● Sewage engineering. ● Electric power, metallurgy, and environmental protection engineering. Overall, glass fiber reinforced plastic (GFRP) pipe can complete underground pipeline construction and installation without excavation. GFRP pipe can directly cross highways, railways, rivers, and ground buildings. This is due to its inherent characteristics of excellent corrosion resistance, lightweight, smooth inner walls, high flow capacity, and good adaptability to geological conditions.
