Low-energy glazings

The application of monolithic silica aerogel as transparent insulation material for windows has been ivestigated for some years. It has been realised that a major problem of an industrial production of aerogel glazings will be the time for evacuation of the aerogel material. However, in a previous EU project a promising method was proposed, so the time for evaluation could be reduced from several hours to a few minutes. The aim of this project was to design and build an apparatus for evacuation and assembly of aerogel glazings up to 60 cm x 60 cm based on the proposed method. The key element of the method is the vacuum chamber in which the aerogel glazing is prior to mounting of the last glass pane. This glass pane is kept above the rest of the glazing while the chamber is evacuated. When the desired gas pressure is reached the glazing is assembled and the chamber is ventilated. Due to the fast process, it can be considered as semi-online, and especially the capital cost is significantly lower for this method in comparison with a true online process. So hereby, a major obstacle is overcome with respect to a first industrial production of aerogel glazings. The apparatus has been constructed and built, and by means of this six aerogel glazings have been made and four of those can be considerd as fully succeeded. The reasons for the failure of the two glazings are perhaps due to the foil applied in the rim seal. The project serves the Danish input to a current EU projct, in which one of the main objectives is to develop a complete process for aerogel glazings of 60 cm x 60 cm covering both the aerogel and the glazing production