Summary
In aluminium foundries, the production of sand cores from artificial resin-bound quartz sand has up to now been associated with the emission of pollutants and odours, as vaporisation, swelling and crack products are formed during casting and the subsequent cooling of the casting moulds. These airborne contaminants are a problem for foundry personnel and the immediate vicinity.
The aim of the joint project was to develop process-integrated primary techniques for avoiding odour emissions. For this purpose, low-odour and low-emission binder systems were developed on a pilot and preproduction series scale, and tested in an automotive parts foundry. The developments were based on the core binder systems, warm-box and mask-form binders used to date, and a polyurethane cold-box binder.
Results:
- Using the developed cold-box binder system (gas resin 7388 and activator 7187), odour emissions were reduced by a total of 84% in comparison with the standard gas resin 4513/activator 4514 bio binder system. The automobile manufacturer who participated in the project has consequently decided to commence serial production of the system. The binder has also been made available to the entire aluminium foundry industry.
- The results provided the foundry chemical supply industry with important impulses for the development of innovative products.
- An ancillary effect was that the techniques used could be optimised for reproducible olfactometric monitoring on a small technical and full foundry scale.
- In the case of warm-hardening binders, no satisfactory development was achieved with regard to reduction of odour emission.
