Cement pipes, also known as pressure pipes or reinforced concrete pipes, are used primarily for urban construction foundation drainage systems, including the discharge of wastewater, flood prevention, and drainage. They are also used for water supply pipes in special factories and agricultural wells. They are generally categorized into: flat-end reinforced concrete cement pipes, flexible bell-end reinforced concrete cement pipes, socket-and-spigot reinforced concrete cement pipes, F-type steel socket cement pipes, flat-end sleeve joint cement pipes, and bell-end cement pipes, among others. Made with plastic concrete, the pipe wall structure is layered after molding, which affects the concrete's load-bearing capacity. The concrete grade is typically C30, but can also be C40. However, the concrete strength at the pipe openings is lower than that of the pipe body, making them unsuitable for use as manholes.