French fittings manufacture opts for maintenance-free shutter mechanism

Brasier Industrie located in the Rhône-Alpes region of France has been manufacturing high-grade-steel accessories for shutters and louvres since 1965. The company recently undertook an internal study to focus on developing a maintenance-free shutter product line. Manufactured from composite materials, the product needed to be suitable for use in harsh environments, such as coastal regions and mountainous areas.

The initial trials were performed using a 50 % glass fibre reinforced polyarylamide (PARA), however, the components failed to deliver the necessary required results. Brasier, therefore took the decision to change both the material and the supplier.

Hamburg based plastics distributor K.D. Feddersen and its’s French subsidiary were selected as the preferred development partners by Brasier. Working closely together, both companies were able to provide the comprehensive technical support necessary for the success of this project.

“When undertaking metal replacement projects using high performance thermoplastics, it is important that the component design is optimized accordingly” says Ian Nott general manager at K.D. Feddersen UK Ltd., the UK distribution arm and wholly owned subsidiary of K.D. Feddersen GmbH & Co. KG.

“In this case a component with a constant wall thickness and the addition of reinforcement ribs was essential due to the enormous forces acting on the component”

Following preliminary discussions with Brasier and the selected moulder, the decision was made to test AKROLOY®, a glass fibre reinforced PA 6.6 blend from AKRO-PLASTIC GmbH (member of the Feddersen Group).

Using this special AKROLOY® PA blend, AKRO-PLASTIC developed a product displaying superior properties compared to standard polyamides when used in metal-replacement applications. One such property is the significantly reduced moisture absorption behavior of AKROLOY® giving an increase in stiffness, strength and creep modulus, resulting in a better dimensional stability of the material.

The replacement of die cast metal components place such high demands on plastics parts – demanding a constant property profile over a broad range of operating conditions. When considering traditional polyamides, even with as much as 60 % glass fibre reinforcement, successes have been the exception due to their increased moisture absorption behaviour.

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 noted, 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 AKROLOY®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 shutter tests, AKRO-PLASTIC developed a special AKROLOY® grade for a part in Brasier’s product portfolio that was required to undergo thermo-lacquering.

“In order to ensure an even application of colour on the component, it is crucial that the material is electrically conductive”, says Ian Nott. “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.