JEC COMPOSITES MAGAZINE - Issue #50 - July/August 2009 - 37

Production An RTM production line with environmental credentials Eparco specializes in the design and manufacturing of non-collective wastewater treatment systems. Its 5m3 septic tanks are manufactured at a rate of 30 units per day on a state-of-the-art RTM production line. ormed in 1995, Eparco stands out from other companies in the sanitation sector through its use of composite materials in the manufacturing of its septic tanks. The choice of using composite materials is sufficiently rare – unique even – in this sector to deserve highlighting. The material most commonly used in this domain is concrete. F Optimised production The production process is perfectly organised. While the mould is in use, the templates are covered with pre-cut Saertex glass fabric, which takes two operators around 10 minutes to do. The use of pre-cut fabrics was introduced four years ago. Polyurethane foam reinforcements complete the structure of the shells. The infusion-curing stage lasts 30 minutes. The 70 litres of resin take only six minutes to be injected; curing lasts 20 minutes; and mould release takes place five minutes after peak time. The full cycle time is 40 minutes. Four RTM stations are in operation simultaneously: one for the lower shell, a second for the upper shell, another for the filter tank and the final one for the risers. The lines are equipped with Matrasur injection and control systems. Following mould release, the shells are transferred to 5-axis automated machining centres. Two 30,000-litre tanks – equivalent to 2 weeks of production – supply the RTM lines with resin after preparation. An in-house lab prepares and monitors the dosing permanently. The gel and curing times are subject to precise control. They must be compatible with the cycle time. The production lines are equipped with semi-automatic systems, keeping human intervention to a minimum. The opening of the moulds is Gilles Boury, Director of the Senan plant. RTM as a process Eparco has always been an exponent of the RTM process. The composite moulds are produced in-house and the half-shells are produced as standard, i.e., through application of the gelcoat followed by impregnation of the glass fabrics. The new production line was commissioned in 2008, following 18 months of development and study. Not only is the new facility more efficient, it is also more environmentally friendly. With this new production line installed in its Senan (France) plant, Eparco has tripled its production capacity, growing from 10 complete systems daily to over 30 today. A complete sanitation system as developed and proposed by Eparco is composed of a septic tank, itself made up of two shells, two risers and a filter tank. To this is added a dispersion-irrigation kit. This new installation is characterised by a major new feature: the elimination of the gelcoating stage. A surfacing veil is added to guarantee a perfect finish. Eparco has been able to do away with this stage by using a new resin from Scott Bader, which is self-coloured in an attractive green colour. The 6 mmthick half-shells weigh a mere 110 kg. The reinforcement accounts for around 30% of the weight. The production process is perfectly organised. No50 July-August 2009 / jec composites magazine 37

JEC COMPOSITES MAGAZINE - Issue #50 - July/August 2009

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #50 - July/August 2009