In all modern liquid composite moulding applications it is very important to track the resin's arrival at critical locations for quality but also for process control purposes
Towards high-volume composites manufacturing of automotive parts, RTM is considered more and more. In this case it is very important to have the trusted resin arrival timestamp at critical locations. Resin arrival signals may be necessary for opening or closing feeding or evacuation lines when the resin has exited the cavity from a specific gate. Also resin arrival indication can contribute to the calculation of the ‘real’ permeability of the fibre preforms either in specific lab-devices or even at the real moulding conditions. This can be done by placing specific small film sensors into the cavity. In most of the applications just for resin arrival or temperature recordings Optiflow and Optiview are used. Optiflow can track up to 4 sensors while Optiview can handle up to 10 Optiflow simultaneously. Using the Optiflow system with the built-in continuous good contact check it is always safe to use this system not only for process development but also for process automation through the available relay outputs. Both temperature history and resin arrival timestamps are recorded and stored in the computer. Resin arrival can be measured either by disposable flexible sensors or with permanent ones. The permanent sensors can be installed either in the cavity or at the inlet/outlet gates or at the feeding/evacuation lines.Furthermore, when both resin arrival and cure are considered, the use of the more accurate Optimold system can be considered. When resin arrives at the sensor a relay output opens and Optimold continues to monitor resistance and temperature for cure monitoring.