CCBM & RTM are methods of placing and consolidating a glass reinforced polyester or other resin matrix into a mould without spraying or handling of wet resin.
In brief the glass fibre reinforcement (including a flow media) is placed into the mould and shaped to fit. A flexible bag or structured inner liner is then placed into the mould to locate the reinforcement and any inclusions such as fixing plates etc. The cavity created by the glass is evacuated by vacuum and then the resin is infused or drawn into the reinforcement matrix through injection ports. Mould flow of resin is controlled so that wet-out of the reinforcement is 100% with no voiding or air entrapment in the laminate. In the process a very precise resin to glass ratio is achieved yielding optimum mechanical properties, predictable and uniform laminate thickness and excellent surface finish to the inner faces.
CCBM (Closed Cavity Bag Moulding)
The CCBM system employs a reinforced flexible bag that is placed in the mould over the pre cut and placed reinforcement. The resulting cavity is evacuated and resin introduced to infuse through the mat. Placement of reinforcement is very precise, other components can be inserted with the reinforcement and the resin glass ratio can be accurately controlled to produce uniform parts with weight, and strength in specified areas.
Light RTM (Closed Moulding)
Similar to CCBM but employing a hard inner liner, usually polyester or vinyl-ester resin. Additional advantages include ability to produce 2 high gloss faces, interior surface gelcoated and very precise thickness of laminate.
Quality
As stated above the laminate resulting from infusion tightly controls the resin:glass ratio providing parts of optimum strength and strength or inserts in specific areas. From an engineering perspective the resin matrix is primarily used to hold the glass reinforcement in place. While the resin is relatively flexible the glass is rigid with high tensile properties. The more accurate the use of resin and the better located and tightly packed the glass matrix, the more mechanically efficient the reinforcement.
