JetPreg for Honeycomb Structures
Cannon LS10 mixing head provides numerous advantages when used with Polyurethane spray formulations and the JetSpray technology.
FASTER, CLEANER, MORE PRECISE AND FLEXIBLE: THESE ARE THE REASONS WHY CANNON SOLUTIONS ARE FINDING AN INCREASING SUCCESS AMONG THE USERS OF HONEYCOMB COMPOSITES MADE WITH SPRAY FOAMS.
An increasing number of PUR processors is orientated towards spray foams for the production of lightweight Composites: one of the reasons is the lower investment demanded for a spray equipment versus an HP- RTM solution. This opportunity has generated numerous new products, commonly defined by the industry with the name of BayPreg *, ElastoFlex ** or others obtained making a sandwich of a corrugated paper( an honeycomb structure) lined on both sides with sheets of a non-woven glass tissue, that is impregnated with a fast-reacting Polyurethane formulation and clamped to shape in a press, immediately after the application of the chemicals. This technology has been developed nearly 15 years ago, but now, as pressure to lightweight increases in the automotive industry as a way to reduce emissions, this application is further growing, to pull weight out of vehicles. Typical lightweight parts obtainable with these structures are trunk load floors, hatchbacks, sun shades and entire roofs. Chemical suppliers are developing faster formulations, and an appropriate range of metering and mixing devices is required to process them efficiently with a mass-production approach. The possibility to distribute very evenly these fast-reacting PUR formulation over the entire surface of a large mould prior to the clamp closing operation – rather than forcing it in a closed mould by means of high-pressure injection – allows for significant advantages:
· There is no resistance, generated by the reinforcement in a closed mould, to overcome a flow of liquid chemicals, therefore the pressure needed to maintain closed the polymerisation press is much lower than that required using a classic high-pressure injection method; this translates in simpler clamping equipment, less expensive to buy and to operate.
· The Polyurethane foam is applied with an optimum distribution of densities, only where it is requested: this reflects in raw material savings. And, as a bonus, there is no mark left on the injection point, that sometimes is difficult to hide or remove.
· The application of the foam can be run in hidden time, outside the press, while another part is clamped and polymerising: this provides significantly shorter cycle times and an increased production per working island.
In order to exploit all the advantages deriving from this spray foam technology it is compulsory to use dosing, mixing and distribution devices that provide the highest efficiency, otherwise the above described benefits are lost: in particular, a high efficiency is demanded during the foam application, avoiding to spend more time that it is necessary on each part of the mould.
Dedicated heads to optimise the job Listening to the needs of the applicators and working in strict cooperation with the Raw Material Suppliers Cannon have developed JetPreg a special set of solutions for the use of industrial spray foams, that as usual starts with a very efficient mixing head, the Cannon LS10, that provides the performances required by the most
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