Reinforced plastic sheet machine and method

摘要

Reinforced plastic (FRP) panels of substantial width are manufactured continuously in a machine utilizing two stainless steel belts, with an inner belt trained about a driven rotating heating drum and an idler sheave. An outer belt is trained about the inner belt as it passes around the drum and also about three idler sheaves, two being employed to direct the outer belt about the inner belt and the third being employed for tensioning and tracking purposes. An additional idler roll is employed as a nip roll where the two belts join substantially tangent to the heating drum. Both belts may have substantially horizontally flights for application of heat curable resin. A fiberglass or other reinforcement mat is fed into the nip. The resin such as unsaturated polyester may be fed in controlled doctored amounts of liquid form to provide a bead or puddle at the nip into and through which the mat is drawn. The heat of the drum initiates the cure to form a wide controlled thickness reinforced sheet. The speed of rotation of the drum and heat is controlled to obtain the desired product. Alternatively, thermoplastic sheets such as olefins may be fed to the nip on each side of the mat to form reinforced sheet. Again the feed rate is such so that a wetting bead of melt is obtained at the nip into which the fiberglass or reinforcing mat is drawn.