| 摘要 |
PURPOSE:To improve the accuracy in the measurement of explosion concentration with an even cloud of dust by forming a turbulance in a stream accompanying a sample dust by means of a turbulance grid provided between a sample tray and an explosion cylinder in a Hartmann's explosion tester. CONSTITUTION:A body 1 has a jet hole 3 at the bottom thereof communicating to a compression air feeder 2 while an explosion cylinder 8 is screwed down onto a sample tray 5 with a roughly semispherical concave. A turbulance grid 10 is provided at the bottom of the explosion cylinder 8 and an ignition electrode 6 is provided at the center thereof with a filter paper 7 arranged at the upper end thereof. In operation, a sample is placed into the sample tray 5 and the explosion cylinder is locked. A stop valve 22 is opened and a compressed air is introduced in an air reservoir 24 from an air cylinder 23. Then, a valve 26 is opened and a cloud of dust is in the cylinder and exploded ignited with an electrode 6 after a cartain time. This creates an even cloud of dust thereby enabling the measurement of the explosion concentration easily at a high accuracy. |
