Description of process

Resin injection

The RTM-process, “Resin-Transfer-Moulding” or “Harzinjektionsverfahren” as is called in German is a processing technology to produce fibre reinforced composites (FRP).

Carbon, glass and aramid fibres are the most well known reinforcing fibres, which are impregnated with a matrix system (Resin-hardener mixture) and processed to produce components.

Closed moulds

In the RTM-process the semi-finished fibres are either directly or in the form of a preform placed into a mould comprising a lower and an upper half. After the mould is closed the matrix system is injected into the mould cavity using an injection moulding machine at pressures of up to 35 bar. The hardening starts instantly within the heated mould.

Advantages of the process

As the component is produced and hardened in a closed mould, the component has smooth surfaces on either sides, consistent wall thickness and fibre volume content in addition to dimensional accuracy.

Thus this technology is most suited for production of components that are exposed to heavy structural stresses or need to meet special requirements in terms of dimensional accuracy, stability and reproducibility.

The option of having a partial automation and full automation makes this process a unique production technology suitable for serial production of complex, three-dimensional and continuous fibre-reinforced components.