1100°C AAF Ashing Furnaces

These models are heated by wire heating elements protected from chemical and mechanical damage by a high quality, hard wearing alumina based liner. The graded winding and heating from four sides allow the elements to compensate for heat loss and they are additionally used to preheat the air entering the furnace. Temperature uniformity within the chamber is therefore excellent, despite the higher airflow through the chamber.

The AAF 11/3 and AAF 11/7 have a large floor area which allows many samples to be accommodated and because of the low chamber height the airflow is held close over the samples to promote burning. High airflow of between 4-5 changes per minute is ensured by use of an air inlet and a tall chimney, however it is not too high to disturb the samples in the crucibles, or chill them, as the incoming air is preheated.

The AAF range is ideal for ashing materials such as food, plastics, coal and other hydrocarbons. The AAF 11/7 furnace complies with the following industry standards BS 1016 part 4, ISO 344 and 1171, ASTM D2361, D2795 and D3174.
The AAF 11/18 has high grade heating wire mounted behind silicon carbide tiles to protect against carbon or corrosive atmospheres. A two tier shelf is supplied as standard, which doubles the furnace capacity.

The AAF 11/8 has high grade heating wire mounted behind silicon carbide tiles to protect against carbon or corrosive atmospheres. A two tier shelf is supplied as standard, which doubles the furnace capacity

Some analysis techniques may be effected by alumina or silica dust (Al₂O₃ or SiO₂), the materials normally used to construct furnace chambers and to avoid this the GSM ashing furnace chamber is constructed from a fused quartz material.

This minimises the risk of dust falling from the chamber roof into the sample crucibles, however the door insulation is moulded ceramic fibre which may produce small dust particles and therefore dust cannot be entirely eliminated.

This Ashing Furnace design also offers superior containment of aggressive and corrosive vapours such as H₂SO₄, HNO₃ and HCl, keeping them away from the heating elements.

Additionally if an optional gas inlet is specified the enclosed design minimises gas leakages from the chamber.