CompositesWorld
Issue link: https://cw.epubxp.com/i/841219
NEWS 29 CompositesWorld.com French development led by R&D; facility Cetim (Nantes) in part- nership with suppliers Pinette Emidecau Industries (Chalon sur Saône), Compose (Bellignat) and Loiretech (Malville) and local government Région Pays de Loire. QSP feeds, cuts and assembles multi-thickness, multi-oriented inputs into tailored preforms in 40-90 seconds. Fast, robotic transfer (<5 seconds) then moves preforms through a two-step preheat before thermoforming them in a 500-MT Pinette press with a 2,000-bar, 0.4-liter shot KraussMaffei (München, Germany) injection unit for overmolding, using a 200-kW RocTool (Le Bourget du Lac, France) rapid heat/cool induction system. e line begins with thermoplastic pultrusion of glass or carbon fiber unidi- rectional (UD) tape at the right thick- ness (1.5-3.0 mm) and width (100-300 mm) for the process. "With thin tapes, you need three to four layers in the preform," explains Franck Bordellier, lead QSP development engineer at Cetim. "We'd rather have these already plied in the tape." e goal is to produce tape at a cost of €3/kg (US$3.27/kg). "Pultrusion can reduce cost because it is a continuous process," says Bordellier. "If we run the line at 3m/min we can beat glass fiber/polyamide organosheet at €7/kg [US$7.64/ kg]." is tape is fed directly into the Pinette-supplied cutting cell and cut while flat, using an ultrasonic (UT) technology developed by Sonimat (Lencloître, France) that operates at 400 mm/sec. Cut tape patches are then transferred to storage or the preform assembly module, which uses a patent-pending tape placement concept to affix patches with UT welding. "It is very efficient because it is more of a parallel vs. serial build process." Assembled preforms exit via conveyor and are moved by robot into a conduction oven, which heats the inside of the preform, and then into an infrared (IR) oven which heats the outer surfaces. "Conduction provides maximum calories inside the preform," says Bordellier, "which allows us to put a lot of heat into higher thick- ness areas without degrading the lower thickness areas." From the IR oven, located just outside the press, preforms lose only 15°C before thermoforming begins. "e preform's thermal profile has a direct effect on part performance," notes Bordellier. Parts are demolded on the opposite side of the press by a robot with needle grippers from Schmalz (Glatten, Germany). Bordellier describes the line's process control, "We have integrated a thermal camera for IR heat control, a laser system for preform placement and an optical system for quality assur- ance through the process." He notes that QSP has demonstrated hundreds of parts. Among them is the L-shaped, multi-material automotive seat struc- ture, developed with Faurecia, which integrates 13 patches of 1.5-mm, 2-mm and 3-mm thick organosheet and UD tape into a preform in 40 seconds. e 2.5- to 3-mm thick part, with integral plastic and metal fittings, is formed in a one-shot, 60-second molding cycle. Four parts/minute and multifunctional tow Although Compositence (Leonberg, Germany) has developed an AFP-based method to produce near net-shape preforms, it has also moved beyond, working with BMW to develop what it calls multifunctional tow, which dramatically boosts drapability and material throughput. e main elements of its system include a spool creel, 2D (gantry) or 3D (robot) manipulating system with exchangeable, quick-release AFP head and a rotary table on a linear rail (Fig. 3, p. 28). Its newest system, ready for production later in 2017, will lay up as many as four preforms (e.g., 1.25m by 0.75 mm) simultaneously, in 1 minute. Both systems can handle towpreg, dry fiber and thermoplastic tape. omas Dobiasch, head of sales at Compositence, says conven- tional AFP typically uses 0.25-0.5-inch (6.35-12.7-mm) wide tapes, derived from the process' aerospace origins. Developed for FIG. 5 More versatile version of a pioneer preforming process Eppingen, Germany-based Dieffenbacher's new Fiberforge 4.0 preforming system boasts material throughput of up to 490 kg/hr, layup speed of less than 1 second per course and the capacity to combine up to four different types of tape in one part. Source | Dieffenbacher Automated Preforming, Part 1 Able to keep pace with part counts in the millions, preforming is no longer a production bottleneck.