Safety characteristics are essential for the design of preventive and protective explosion measures. According to international standards explosion characteristics of dust clouds are determined in 20-L-sphere and 1-m3-vessel.
The ignition of respective dust samples is realized with special pyrotechnical igniters with energy of 1 kJ or 5 kJ which are defined in the testing standards.
However Sobbe in Germany is the only company at the moment which sells such igniters.
The paper presents results of a comparative study between the 5 kJ Sobbe igniter and a 5 kJ igniter manufactured by Simex in Czech Republic.
The study has been conducted under participation of BAM Federal Institute for Materials Research and Testing, Institute for Occupational Safety and Health of the German Social Accident Insurance (IFA), Berufsgenossenschaft Nahrungsmittel und Gastgewerbe (BGN) and Swiss Institute for Promotion of Safety and Security (Swissi).
For the study six dusts from different product groups with various explosion severities and ignitabilities were chosen.
The tests were carried out in the 20-L-sphere as well as in the 1-m3-vessel. Maximum explosion overpressure Pmax, dust explosion constant KSt and lower explosion limit LEL were determined.
Furthermore tests with a high speed and a thermal imaging camera were carried out, in order to compare burning time and flame pattern of Sobbe and Simex igniter.
explosion characteristics of dusts, 20-L-sphere, 1-m3-vessel, pyrotechnical igniter, dust explosion testing