What are the classifications of glass fiber roving

April 26,2022

Abstract: Glass fiber products are products made from glass fiber as raw materials according to different usage requirements. They can be roughly divided into two categories: non-woven products and textile products. Glass fiber textile products can be divided into yarns and fabrics according to product form. two categories. There are many commonly used glass fiber products, mainly including roving, plaid, glass fiber mat, chopped strand, ground glass fiber, glass fiber fabric, combined glass fiber reinforcement, glass fiber wet mat and so on. Let's take a look at the classification of glass fiber roving

1. Untwisted roving

It is made up of parallel strands or parallel monofilaments, and can be directly used in some composite material forming methods, such as winding and pultrusion, because of its uniform tension, it can also be woven into untwisted roving fabrics. for:

(1) Twistless roving for jetting: Twistless roving suitable for FRP jet molding, with good cutting properties, high efficiency of dispersing into strands after cutting, and excellent overmoldability and resinous properties of chopped strands. It has the characteristics of fast infiltration and good degradation performance of the original yarn tube.

(2) Twistless roving for SMC: SMC is a sheet molding compound. When manufacturing SMC sheet, the roving for SMC should be cut into the length of lin (25mm) and dispersed in the resin paste. Therefore, roving for SMC is used for SMC. The requirements are good choppability, less filaments, excellent antistatic properties, and the chopped strands will not stick to the knife roller during cutting.

(3) Untwisted roving for winding: The winding method is used to manufacture FRP pipes and storage tanks of various diameters. The requirements for the roving for winding are as follows: good tape-forming properties, in the shape of a flat ribbon; good disintegration of the roving, no looping out of the fiberglass SMC roving when it is unwound from the bobbin, and no "bird's nest"-like messy filaments; uniform tension , no drape phenomenon; uniform linear density, generally less than ±7%; no twist roving has good permeability, and it is easy to be wetted and saturated by the resin when it passes through the resin tank.

(4) Untwisted roving for pultrusion: It is used to manufacture various profiles with consistent cross-sections, which are characterized by high glass fiber content and high unidirectional strength. The roving for pultrusion can be a combination of multiple strands or a direct roving, and the various performance requirements are roughly the same as those for winding rovings.

(5) Untwisted roving for weaving: it is used for weaving various thicknesses of plaid or unidirectional untwisted roving fabrics, which are mostly used in the hand lay-up FRP molding process.

(6) Untwisted roving for preform: In the preform process, the untwisted roving is chopped and sprayed onto the web of a predetermined shape, and a small amount of resin is sprayed to fix the fiber web, and then the formed fiber web is Move it into a metal mold, inject resin into hot-pressing molding, and get the product.

#fiberglass #Roving #SMC