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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