Direct Roving Fibers: are supplied in a cylindrical package, as bobbins so that the thread structures would not be damaged.
Choppable Fibers: are distrubuted in the pipe by cutting in a way similar to the single-direction continuous fiber.
Reinforcing Fiber Filaments: are held together with the help of adhersive resin.
Polyester resin is dissolved in styrene monomer, this way, the resin is provided to acquire its final thermoset structure with these cross bonds. Organic peroxide catalyst is being used in order to cure polyester resin.
Sand is used in order to increase the rigidity of the pipe and it is around the neutral axis of the pipe. The sand used generally has high silica content.