Sept. 10, 2015

Engineering thermoplastic structural components and design: the winning couple in the furniture solutions

Performance gap between engineering compounds and metal alloys has also been narrowing during the last decade thanks to the continuous research and development progress in the field of reinforced polymers and related process technologies.

Advanced plastics are daily job for Lati, one of the most important independent European Compounders and the here EFFEGI Brevetti project development testifies how fruitful can be a tight partnership between 60 years experienced material experts and smart designers, skilled in the field of top notch furniture engineering.

A sophisticated hinge system moving the vertical opening doors of hanging wall units dedicated to high-end kitchens: a clear concept describing a rather complicate device, obtained by the mean of an extended engineering and design procedure. The whole system is composed by different parts:

• The first plate onto which all components are mounted
• A multiple leverage system whose movement is smoother thanks to a braking gas piston
• A second plate keeping in place all the parts
• A safety cover enclosing the hinge system
• A third plate constrained to the moving door via the leverages

The target focused on EFFEGI was to replace zamak alloys to cut weight and cost of metal components, introducing top mechanical performance and outstanding surface finish: two mandatory requirements that can hardly be satisfied at the same time because of the poor aesthetics deriving from glass fibres, often blooming on the surface of reinforced compounds. A definitive solution has been found in the LATIGLOSS compounds whose formulation provides:

• top mechanical properties thanks to the presence of 50 and 60% glass fibres, a reinforcement chosen for specific structural use
• perfect surface finish, featuring glossy and homogeneous aspect. The proprietary matrix formulation provides shiny and bright colours, free of all typical defects due to the high amount of glass or carbon fibres
• excellent dimensional stability, even in case of problematic geometries as plates or not stiffened flat surfaces similar to the here discussed part.

LATIGLOSS 66 is based on polyamide 66 and for this reason processing conditions are much more friendly for moulding machine and equipment because lower pressures and temperatures are required to transform the raw material. It is evident how lower processing and manufacturing induced costs lead to a more competitive marketing price for the finished products.

All over the 3D geometry adequately positioned and dimensioned ribs have thus been distributed, wall thicknesses have been revised trying to exploit the benefits deriving from strong fibre orientation along useful directions. Simulation results confirmed how process requirements of LATIGLOSS materials are similar to those of ordinary glass reinforced polyamide 66 compounds featuring a considerable amount of fibers. Also outstanding surface finish can be obtained by regular mould temperature, i.e. 80-90°C. The calculation showed an easy and complete feasibility of the plate without falling into issues due to remarkable viscosity of the melt polymer and following high melt temperatures needed to fill the cavity, as may occur when PPA and other aromatic polyamides are transformed.

As the first metal replacement attempt was successfully accomplished, EFFEGI quickly decided to export this winning solution to all the other part of the whole hinge system and metal to plastics conversion is almost total today.
The superb aesthetic aspect of the molded parts and overall outstanding mechanical performance allow EFFEGI to implement the LATIGLOSS compounds into both structural parts and covers, without loosing appeal or reliability with their Customers whose expectations can never be let down.