The Pultrusion Process

Many Redco FRP (fiberglass reinforced plastic) customers are aware that FRP comes in molded and pultruded forms, but most do not know what the pultrusion process is or how it creates a superior product. Molded FRP is what it sounds like: you have a large mold, you insert glass rovings (strands) and pour plastic resin on it. Once it cools, you eject the product (such as popular FRP molded grating) and your product is done.

Pultrusion; however, is a very different process. As the name sounds, the product is being “pulled” through what is essentially an automated production system. Fiberglass rovings and matting are pulled through a resin saturator and then through a forming die. In addition, and unlike the molded product, a synthetic surfacing veil is added. This veil offers additional UV protection to the product. This works to create a product with exceptional longitudinal strength and more stable, stronger, product that will outlast molded FRP. A short video by Strongwell illustrating this process can be seen here: