A reinforced plastic made of glass fiber or a product thereof as a reinforcing material. The title is glass fiber reinforced plastic, or glass fiber reinforced plastic. Because of the variety of resins used, it is called polyester fiberglass, epoxy glass reinforced plastic, and phenolic glass reinforced plastic. The glass is hard and brittle, has good transparency and high temperature and corrosion resistance; at the same time, the steel is very hard and not brittle, and also has high temperature resistance. Therefore, people began to think that if it can produce a property that has the hardness, high temperature resistance and corrosion resistance of glass, and has the characteristics of being hard and not broken by steel, then this material will be of great use. After research and experimentation, people finally made such a composite material. It is a glass tube that stands shoulder to shoulder with steel.

Glass steel pipe has many advantages such as strong corrosion resistance, smooth inner surface, low energy consumption, long service life (more than 50 years), convenient transportation and installation, low maintenance cost and low overall cost in oil, electricity, The chemical, paper, urban water supply and drainage, factory sewage treatment, seawater desalination, gas transportation and other industries have achieved wide application.

With the acceleration of China's urbanization process and the balance and protection of population, resources and environment, governments at all levels have increased their investment in urban infrastructure year by year. In combination with the needs of advanced science and technology, the varieties and specifications of pipes and fittings are continuously enriched. The output is constantly increasing, the quality is constantly improving, especially the development of plastic pipes is faster, and it has become a hot spot of investment today. Glass steel pipe is one of them.

Where the stiffness level SN = EI / D3, usually in N / m2 as a unit. EI is the circumferential bending stiffness of the pipe wall per unit length along the pipe axis direction, and D is the average diameter of the pipe. The pressure level PN has 0.1, 0.6, 1.0, 1.6, 2.0, and 2.5 MPa; the stiffness level SN has 1250, 2500, 5000, and 10000 N/m2.