French fittings manufacture opts for maintenance-free shutter mechanism

Located in Perrignier/Haute-Savoie, in the Rhône-Alpes region of France, Brasier Industrie has been producing high-grade-steel accessories for shutters and louvres since 1965. The company recently conducted an internal study with a view to developing a maintenance-free shutter line made of composite materials specifically suited for use in harsh environments, such as coastal regions and mountainous areas.

The initial trials were performed with a 50% glass fibre reinforced polyarylamide (PARA) at one processor’s facility, however, the components unfortunately failed to deliver the necessary required results. Brasier therefore decided to change both materials and suppliers.

Hamburg based plastics distributor K.D. Feddersen’s French subsidiary and Injection moulder Moulages Plastiques Du Léman were selected as development partners by Brasier. Together, both companies were able to provide the comprehensive technical support necessary for the successful completion of the project.

“If you want to convert a component previously made of metal into plastic, you have to modify the design accordingly,” says Claude Boulay, sales representative at K.D. Feddersen. “We needed a component with a constant thickness, and due to the enormous forces acting on the component, reinforcement ribs were added so as not to compromise the mechanical properties of the final product.”

Following preliminary discussions with Brasier and the processor Moulages Plastiques du Léman, the decision was made to continue testing with AKROLOY®, a glass fibre reinforced PA 6.6 blend from AKRO-PLASTIC GmbH.

Using this special AKROLOY® PA blend, AKRO-PLASTIC developed a product displaying significantly enhanced properties compared to standard polyamides when used in metal-replacement applications. One such property is moisture absorption, which leads to a decrease in stiffness, strength and creep modulus, resulting in a lower dimensional stability of the material.

Many applications aiming to replace die cast metals place such high demands on plastics parts. Successes with traditional polyamides, even with as much as 60% glass fibre reinforcement, have been the exception owing to these reduced mechanical properties.

By blending PA 6.6 with a partially aromatic CoPA (PA 6I/6T), AKRO-PLASTIC has been able to significantly reduce the effect of moisture on the product properties. Whereas a 50% glass-fiber-reinforced PA 6.6 shows approximately a 50% decline in stiffness in ambient conditions, the partially aromatic AKROLOY PA blend exhibits a decline of less than 10%. With this significant reduced moisture absorption a better swelling behaviour, improved dimensional stability and an increase in glass transition temperature can be demonstrated.

The fittings used to anchor the shutters are between 30 and 80 cm long, depending on the size of the window. After injection moulding of PARA for such long parts (in some cases quite considerable) irregularities and an uneven surface finish were noticed, these were not evident in the selected PA blend. A further benefit when selecting AKROLOY® is the significantly lower processing temperature, PARA is processed at a mould temperature of 170°C whereas PA requires only 90°C.

Distributor K.D. Feddersen and compounder AKRO-PLASTIC are both part of the international Feddersen Group, giving them a wealth of technical expertise in engineering plastics to draw on. The synergies created by this alliance are used in turn to increase the productivity of many existing and potential customers.

Based on the tests of Moulages Plastiques du Léman, AKRO-PLASTIC developed a special AKROLOY® grade for a part in Brasier’s product portfolio that was supposed to undergo thermo-lacquering.

“In order to ensure an even application of colour on the component, electrical conductivity of the material is crucial,” says Claude Boulay. “With the special compound developed for this application, the customer can achieve excellent and uniform results.”

Brasier is completely satisfied with the material conversion results and fully intends to use AKROLOY® to produce other components (such as turn handles, brackets, and other shutter accessory parts) in the future, thus, allowing raw material purchasing standardization.