Automated prepreg processes

Automated prepreg processes automated fibre placement and automated tape layup... 

Fig. 8-67 Automated-integrated RP vacuum lay-up process that use prepreg sheets that are in the B-stage.

Generally, the process only requires low-cost equipment that is not automated. However, automated systems are used. Automation includes cutting and providing the layout of the cut prepreg in a mold. In turn, the designed RP assembly is delivered to a curing station such as an oven or autoclave. 

The ATL and AFP processes are thus a cross between filament winding with its elaborate automated patterns of fibre laydown and unidirectional prepreg layup with its reliance on the autoclave. The use of automated robotic machinery for the layup gives increased layup speed (vital to economically manufacture these large items in feasible timescale), consistency and freedom from errors compared with manual techniques, as well as ensuring precision in the placement of the tows and tapes. 

Figure 5.1 7 Automated-integrated RP vacuum hand lay-up process that usesTS polyester prepreg sheets...

Obviously, cost is a controlling factor and to compete against Al, the lowest cost form of carbon fiber must be used in conjunction with an automated high speed lay-up process. These criteria have been exemplified by Mills and co-workers [12], working at Cranfield University, who have achieved these aims by developing a machine that can achieve a prepreg output of about 40 kgh ... 

Autoclave processing is used with prepregs with lay-up realized by automated means or by hand. The assembly is vacuum-bagged in order to minimize the presence of volatile substances (responsible for void/defect growth during the... 

In thermo set tape laying, the manual laying process of the prepreg is automated. This can be done directly inside the mold or through an intermediate step of a flat textile structure (prepreg laminate). The aforementioned conditions apply for the mold design and the mold requirements. 

---