The Water2Move project aimed to develop a process for the production of lighter and medium-sized plastic components to replace metallic components and structures. This process involves combining injection moulding technology of polymeric foams with the aid of water injection. These processing methods are generally used individually and aim to reduce the mass/weight of the plastic components to be produced.

Water-assisted injection moulding is a technology used for the production of components with hollow/oca sections. The process consists of injecting water after the mould is closed and injecting the polymer until the moulding zone is completely filled. The water injection will push the polymer out of the core of the part thanks to the high pressures of the water, but also because the polymer is still in a viscous state, facilitating its flow.

The advantage of joining the water-assisted injection technology to the polymeric foam injection process is the possibility to remove more material from the injected components in the larger volume areas, thus creating foam matrix (microcell) components with hollow internal sections. This union of technologies promotes the creation of lighter components than those currently available in the industry, particularly in the automotive components sector and in the production of medium-sized structures.

The Water2Move project thus intends to evaluate the safety and viability of creating lighter structures through this technology and, consequently, the reduction of energy expenditure in production. Using this technology will be developed as a demonstrator: a bicycle frame. This element is subject to considerable loads, requiring a careful choice of geometry and reinforced technical polymer, in order to make possible the production of bicycles by moulding.

This project, which has the contributions of LIDA – Arts and Design Research Laboratory and CDRSP – Center for Rapid and Sustainable Product Development of the Polytechnic of Leiria, CEIIA – Center for Engineering and Development, and the companies Plácido Roque, Polisport, and Moldetipo, also provides the definition of a new set of standards and best practices for the design of this type of mould.

Photos: Pedro Cá