Composite manhole covers are made from fiber-reinforced thermosetting composites based on unsaturated polyester resin - also known as Bulk Molding Compound (BMC) - using compression molding technology; they represent a new type of eco-friendly cover. Manufactured using a high-temperature, high-pressure, one-step compression molding process, they feature a high degree of polymerization and density, as well as excellent impact and tensile strength. Key benefits include wear resistance, corrosion resistance, rust-free performance, and freedom from pollution, all while requiring virtually no maintenance.
Characteristics of Composite Manhole Covers
These covers feature internal reinforcement using a steel mesh, with special strengthening applied to critical areas. In the event of unavoidable external impact, pressure is rapidly dispersed to ensure personnel safety. They contain minimal metal; the steel framework accounts for less than one-tenth of the total weight, offering little value to thieves. Furthermore, the cover's high structural strength makes it extremely difficult to extract the small amount of steel contained within.
Features of Polymer Resin Composite Manhole Covers
1. High Strength: Exhibits exceptional flexural and impact strength, along with high toughness; the product will not crush or break under long-term use.
2. Attractive Appearance: Features an exquisite surface design and adjustable, vibrant colors that enhance the urban environment.
3. Lightweight and Convenient: Weighing only about one-third as much as cast iron, these covers are easy to transport, install, and repair, significantly reducing labor intensity.
4. No Scrap Value (Natural Theft Deterrence): They hold no resale value for scrap, acting as a natural deterrent against theft; structural designs can be customized to ensure safety within the manhole.
5. Superior Weather Resistance: Thanks to scientific formulation and advanced manufacturing equipment, the covers can be used in environments ranging from -50°C to +300°C.
6. Durability: Resistant to acids, alkalis, corrosion, and wear; capable of withstanding heavy vehicular traffic and offering a long service life.
