Besides fiberglass pultruded profiles, pulwinding profiles, hand lay-up products and carbon fiber products, injection molding products are very popular in many industries. Today we’ll talk about injection molding technology principle and advantages and disadvantages.
Injection molding process is to make two kinds of polyester respectively ejected from on both sides of gun with mixed lead agent and accelerant, at the same time, the fiberglass roving which has been cut off is ejected from the center of the spray gun and mix with resin evenly, sedimentary to the mould, when deposition to a certain thickness, make compaction with roller to ensure fiber can be impregnated resin and remove bubbles, then goes to curing process to be a product.
Advantages of injection molding technology: (1) fiberglass roving replaces the fabric can reduce the material cost; (2) production efficiency is 2 to 4 times than hand lay up process; (3) products have good integrity, no seams, interlaminar shear strength is high, there is high resin content, corrosion resistance, it can be resistant to leakage; (4) it can reduce the fly edge, cut cloth scrap and surplus glue consumption; (5) the product size and shape won’t be limited when designing.
Its disadvantages are: the content of the resin is high, the strength of product is less than products with high glass fiber content products.
Injection molding efficiency is about 15kg/min, it is suitable for large hull manufacturing. It has been widely used in machining, machine cover, the whole bathroom bathtub, auto components and large relief products etc.