The main raw material of FRP pipe winding is resin, fiber reinforced material and filler.
(1) resin matrix.
Resin matrix refers to the curing agent and resin composition of the liquid system. The chemical corrosion resistance, heat resistance and resistance to natural aging of the winding products mainly depend on the properties of the resin, and also have a great influence on the process and mechanical properties. The resin used in filament winding is mainly unsaturated polyester resin, and it is also used as bismaleimide resin and epoxy resin. For general civil products such as cans, tubes, etc., the use of unsaturated polyester resin. Epoxy resin can be used for winding products with high compressive strength and interlaminar shear strength. Aerospace products are made of bismaleimide resin with high moisture resistance and high fracture toughness.
(2) reinforced material.
The reinforcing material used for winding is mainly composed of various kinds of fiber yarn, such as alkali glass fiber yarn, alkali free glass fiber yarn, high strength glass fiber yarn, carbon fiber yarn, aramid fiber yarn and surface felt, etc..
(3) filler.
There are many kinds of fillers, which can improve the function of the resin matrix, such as improving the wear resistance, increasing the flame retardancy and reducing the shrinkage. The addition of hollow glass beads in the glue can improve the rigidity of the product, reduce the density and reduce the cost. In the production of large diameter buried pipeline, often add 30% quartz sand, in order to improve the rigidity of the product and reduce costs. In order to improve the bonding strength between filler and resin, filler should be cleaned and treated with surface active.