This page contains a Flash digital edition of a book.
Industrial Solutions


Fast RTM for Epoxy-based moulded composites: more solutions from Cannon!


The recent introduction of new Cannon technologies for the manufacture of Epoxy-based moulded composites was awarded with numerous positive answers from the market. Cannon have introduced three different impregnation systems based on high-pressure technology. A whole range of solutions is now available to respond to different needs and processes. Cannon supplies today the widest set of tools, including dispensing and mixing devices, preformers, presses, moulds, manipulators, ovens and controls.


use of viscous formulations, characterised by low flowability: being directly deposited in-situ the liquid does not need to flow through the fibers, avoiding any distribution problem. A certain degree of part's three-dimensionality can be approached without problems, since the head can be tilted on a fourth axis over the vertical sides of a mould during the spraying operation. The use of a Cannon proven airless mixing head significantly reduced the amount of entrapped air, enhancing the transparency and the mechanical characteristics of the final layer of hardened resin


ESTRIM LL (Liquid Laydown) - the Epoxy formulation is laid over the Carbon mat in “liquid ribbons” of varying width, typically from 40 to 120 mm, perfectly impregnating the reinforcement and limiting the possibility of air inclusions in the moulded part. This technique allows for the production of very large parts, wetting uniformly the huge, almost flat preforms that characterise parts such as roofs, engine hoods, fenders and doors. The reactivity of the systems being controllable on a part- to-part basis, this system allows for a comfortable laydown time even for the largest pieces. As in the SL alternative, the formulation does not need to flow through the mould, therefore guaranteeing the most homogeneous distribution of liquid resin in the Carbon reinforcement.


The new high-pressure, plunger-piston dosing unit for the release agent feeds the non-reactive chemical directly in the resin stream just before the head's injector.


development projects and another, very cost conscious, dedicated to industrial production. The first, fitted with numerous options that make it suitable for the flexibility demanded by a team of an R&D department, features small tanks and a components circuit very easy to be purged, allowing to run numerous sets of trials with different formulations in the same day. The second is designed for a more standard, repetitive sequence of injections, providing a reliable workhorse at a very appealing price.


The E-System dosing unit for fast Epoxy-based RTM in a very flexible version for R&D laboratories.


Cannon launched three years ago their new high-speed RTM technology for Carbon-reinforced composites based on Epoxy resins. The new process, called ESTRIM (Epoxy Structural Reaction Injection Moulding) gave the opportunity to the industry to use new, fast reacting Epoxy formulations, developed to comply with the high productivity required by the automotive industry, for their rising number of structural composite parts. Based on a series of integrated products - Carbon reinforcement handling systems, dedicated preformers, high- pressure dosing units for Epoxies, multi-component mixing heads with different distribution methods, moulds, large-size hot press with accurate parallelism control (for part forming), low-tonnage cold press (for part controlled cooling) and relevant handling systems of preforms and moulded parts – the ESTRIM process immediately received a positive response from the market. The possibility to go from a traditional 30-minutes cycle of conventional RTM down to 3 minutes with ESTRIM appealed OEMs and Tier 1 companies. All the major players in the field of automotive composite parts visited during the past 36 months the Cannon R&D laboratory in Italy, either to run moulding tests with their own raw materials and moulds or to discuss directly the supply of equipment for their composite research and production departments. The intense exchange of experiences matured during these visits stimulated the development of new methods for distributing the liquid Epoxy resins in the Carbon preforms. In addition to the ESTRIM RTM fast injection technology, Cannon have developed two alternative methods for the impregnation of these more or less flat mats, both to be applied in open mould prior to the closing of the press:


ESTRIM SL (Spray Laydown) - the Epoxy formulation is sprayed directly over the reinforcement, covering each square centimetre of mould with extreme precision, applying the desired amount of liquid resin where it is required by the part's geometry. This technique allows for the


ESTRIM SL, a new Spray Laydown impregnation system, provides a calibrated distribution of Epoxies over Carbon preforms.


Worldwide recognition Up to date, numerous contracts for these Epoxy-dedicated technologies have been signed with major manufacturers of parts (both car manufacturers and Tier 1) and Raw Material Suppliers, in Europe and Japan. Several more are under discussion, and the relevant news will be disclosed if and when this will be allowed by the clients.


New tools for customers in Cannon R&D facilities


ESTRIM LL, the new Epoxy Liquid Laydown impregnation system developed by Cannon for a very homogeneous distribution of liquids over Carbon preforms.


The optimization of the above process not only keeps low part- to-part cycle time, but also requires lower compression force, and thus reduced capital investments which in the end leads to lower part cost. We should not forget the development of new alternatives for the traditional high-pressure injection in closed moulds, performed with the original ESTRIM technology. The experiences matured in the past in the field of short-stroke polymerisation presses have allowed for at least two more injection methods: 1. The resin can be injected with a variable output, commanding the operation by reading the internal pressure in the moulds. The signal is sent to the unit's PLC, that defines the new output value to be applied and commands the dosing pumps in real time, working in closed loop control. The press does not move during the injection. 2. The injection-compression method can be applied, by leaving the mould partially open during the injection (still guaranteeing the tightness of the cavity) and applying the final compression stroke at the end of it.


Further developments are announced Cannon announced at JEC Composites Show 2013 in Paris the three-component dosing method for ESTRIM. The third component, a release agent, is metered at a very low output (few grams per minute) by a separate new plunger-piston high- pressure dosing unit: the flow of release agent enters in the resin stream immediately before the relevant injector, on the mixing head. Thoroughly blended in with a static mixer, this non-reacting chemical is dosed with extreme precision to the reacting formulation. The hydraulic valve controlling the third component ensures a perfect feeding synchronization of this stream into the resin, avoiding any possible contamination of the material. The head performing this operation is an FPL7 2+1K, which can be supplied in various configurations: for closed-mould injection, for Spray Laydown (SL) or for Liquid Laydown (LL). Two versions of the Cannon E- System machine are now available: one extremely flexible for laboratories and


The new Cannon FPL 7 2+1 mixing head, featuring the injection of a third component perfectly pre-blended in the resin stream.


2


The search for new solutions and the intense cooperation with the major players involved in this business convinced the Cannon management to invest even more resources in this field of activity: in the central R&D laboratory in Caronno Pertusella, near Milano, Italy, more floor space and equipment have been dedicated to the development of Epoxy-based composites. In addition to the just announced high- pressure machine with a three-component dosing method, a new 650 Tons hot press will be installed later this year, allowing for the production of large parts with the customer mould. It will add to the existing 100 Tons hot press that has been extensively used for test plates and small parts.The new clamp will speed up the development of proper processing solutions that require a high degree of integration between dosing machine, mixing head, mould and press. Dedicated R&D continues, at Cannon , with the fundamental contribution of the interested end users and Raw Material Suppliers. An intense calendar of trials has already been defined for 2013, and the available slots are running out! Should you have a real interest in exploiting these resources for a project related with fast Epoxy- based RTM production, please contact Cannon Afros at marketing@afros.it to be put in contact with the relevant team of specialists. With their available, proven industrial solutions for a vast range of needs, Cannon is today the ideal partner for complex – and also for simple – Epoxy processing projects for the composite industry. Once again, the concept of “One-Stop-Shop” for all the chain of equipment and tools can be the winning move for both parties.


Alberto Bonansea, chief of Cannon Central R&D laboratory for reacting formulations, extracts a moulded Epoxy-based composite testplate obtained with the ESTRIM LL (Liquid Laydown) technology.


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12