The composite manhole cover is made of polymer composite material and molded at one time after high temperature molding. It is characterized by high density, strong toughness, and the material itself has no use value, which plays a natural role in preventing theft.
The following are the precautions for the selection of manhole cover selection: raw material selection and processing technology for composite manhole cover.
We all know that composite manhole covers have high polymerization degree, high density, good impact resistance and tensile strength, and have the advantages of wear resistance, corrosion resistance, no rust, no pollution, and maintenance-free. The welding process of steel bars, the strength of the press and the quality of the product determined by the mold and the service life; many bad businesses in order to thicken the manhole cover, in order to increase the weight and output of the manhole cover, a large number of sands, there is no strict requirement for manual welding of steel bars Welding points cause the density of the manhole cover product to be inadequate, and the reinforcement is not strong, which greatly affects the service life of the manhole cover. Such a product breaks at the touch of a light footstep, let alone any safety.
What is a composite material?
BMC is a ball molding compound. It is often referred to as unsaturated polyester pellet molding compound in China. The main raw material is a dough-like prepreg made of chopped glass fibers, unsaturated resins, fillers and various additives. Because BMC lump molding compound has excellent electrical properties, mechanical properties, heat resistance, chemical resistance, and adapts to various molding processes, it can meet the performance requirements of various products. It is widely used in automobile manufacturing and railway transportation. , Construction accessories, mechanical and electrical products.
SMC is a sheet molding compound. The main raw materials are composed of special yarn, unsaturated resin, low shrinkage additive, filler and various additives. It first appeared in Europe in the early 1960s, and around 1965, the United States and Japan successively developed this process. At the end of the 1980s, China introduced foreign advanced SMC production lines and production technology. SMC composite materials and SMC molded products have excellent electrical insulation properties, mechanical properties, thermal stability, and chemical corrosion resistance. Therefore, the application range of SMC products is quite wide. The current development trend is that SMC composites will eventually replace BMC materials.
Fiber-reinforced materials are widely used in composite materials and used in large quantities. For example, carbon fiber and epoxy resin composite materials have specific strength and specific modulus that are several times greater than steel and aluminum alloys. They also have excellent chemical stability, friction reduction and wear resistance, self-lubrication, heat resistance, fatigue resistance, and durability. Creep, noise reduction, electrical insulation and other properties. Composite of graphite fiber and resin can obtain a material with an expansion coefficient almost equal to zero. Another feature of fiber reinforced materials is anisotropy, so the fiber arrangement can be designed according to the strength requirements of different parts of the product. Aluminum-based composite materials reinforced with carbon fibers and silicon carbide fibers can still maintain sufficient strength and modulus at 500 ° C.
The composite material molding process is flexible, and its structure and performance have strong designability. Manufacture of various components by one-shot molding method can improve the structural strength, and the performance of different parts of the component can be improved by the type of fiber and the design of different arrangements. By adjusting the composition, composition, and arrangement of each component of the composite material, the component can not only withstand different forces at different positions, but also can be made into a composite multifunctional product that has contradictory properties such as rigidity, toughness and plasticity. In the application technology of evacuation platforms and cable supports, the "designability" of composite material properties plays a big role.
Zibo Best Energy-saving Materials Co., Ltd. is a well-known manufacturing enterprise specializing in the production and sales of composite manhole covers. Since its establishment in 2004, it has always adhered to the business philosophy of "integrity, pragmatism and innovation". Planning and design, high-quality engineering quality, perfect after-sales service, take root and grow, set a good example in the metal building materials industry, Bester products not only sell well in China, but also in Europe, West Asia, Africa, the Middle East, Russia and many other Countries and regions also occupy a place.