Fire and explosion safety

Potentially-explosive process dust is produced during dry processing or processing with minimal lubrication of aluminum and aluminum alloys. These are categorized in explosion classes St 1 to St 2, depending on grit size distribution, degree of oxidation, humidity and consistence. The risk of explosion or fire is increased through the accumulation of this dust in machining chambers, particularly where classical dry suction extraction systems are involved. Deposits of dust permeated with oil emanating from minimum lubrication systems increase the risk of fire.

Speaking on the subject of fire and explosion protection during suctioning and separation of light metallic materials, Dr. Albrecht Vogl from the Research Institute for Applied System Safety and Occupational Medicine (Forschungsgesellschaft f�r angewandte Systemsicherheit und Arbeitsmedizin (FSA)) in Mannheim states that: "aluminum and aluminum alloy chips and dust are, in principle, combustible. Fine dust from these light metals can form highly-flammable mixtures of dust and air when stirred up, and these can lead to exceptionally powerful dust explosions where an effective source of ignition is present, resulting in extensive damage. Accumulations of chips, dust and fine dust of this nature are particularly encountered in dust extraction systems and separators during suction extraction in material machining processes."

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Al-alloys