Resin rich polyurea-based integrated external layer for reinforced thermosetting resin piping protection
This disclosure describes a reinforced thermosetting resin piping system that is protected from external impact and UV damage by an outer polyurea-based layer. The embodiments described herein can be favorably used for underground and aboveground applications. In some implementations, an RTR pipe includes a core layer that includes a resin and fibers, an outer layer that includes a polyurea-based layer, and an interface layer between the core layer and the outer layer. The methods described herein also outline the process of producing the pipe structure.
1. A method of manufacturing a pipe, comprising:
immersing fibers or glass rovings in an uncured resin to yield impregnated fibers or impregnated glass rovings;
winding the impregnated fibers or impregnated glass rovings over a mandrel, wherein the impregnated fibers or impregnated glass rovings are wound under tension;
partially curing the resin;
applying a polyurea-based layer to the partially cured resin, applying the polyurea-based layer to the partially cured resin comprises applying a polyurea-based layer that comprises fibers or glass rovings to the partially cured resin;
forming an interface between the partially cured resin and the polyurea-based layer, wherein in the interface the impregnated fibers or impregnated glass rovings in the partially cured resin project into the polyurea-based layer;
allowing the polyurea-based layer to dry; and
completely curing the resin and polyurea-based layer.
2. The method of claim 1 , wherein immersing fibers or glass rovings in an uncured resin comprises immersing fibers or glass rovings in a polyester-, vinylester-, or epoxy-based resin.
3. The method of claim 1 , wherein immersing fibers or glass rovings in an uncured resin comprises immersing e-glass fibers in an uncured resin.
4. The method of claim 1 , wherein applying the polyurea-based layer that comprises fibers or glass rovings to the partially cured resin comprises applying a polyurea-based layer that comprises e-glass to the partially cured resin.
5. The method of claim 1 , wherein applying the polyurea-based layer that comprises fibers or glass rovings to the partially cured resin comprises winding the polyurea-based layer that comprises fibers or glass rovings over the partially cured resin.
6. The method of claim 1 , wherein applying a polyurea-based layer to the partially cured resin comprises applying a polyurea-based layer that includes aliphatic and aromatic functional groups.
7. The method of claim 1 , wherein winding the impregnated fibers or impregnated glass rovings over a mandrel comprises winding a layer of impregnated fibers or impregnated glass rovings that is between 5 mm and 8 mm thick over a mandrel.
8. The method of claim 1 , wherein applying a polyurea-based layer to the partially cured resin comprises applying a polyurea-based layer that is less than 2 mm thick.