鋳造工場におけるじんあい分布について

抄録

  Experimental and practical investigations have been made on the characteristics of the distributions of dust particles. Rōken Dust Counter was used in measuring in horizontal and vertical planes. Number of dusts per cubic cm. air and sizes of each particle were measured.
  Dusts were generated by compressed air in artificial dust generation experiment, and in practical investigation sampling was made at the places “shake out, knock out, old sand treatment, etc”.
  Thus, the following results were obtained.
  1. The majority of dust particles in air are of below one micron in diameter. Numbers of dust particles are smaller above the generating point and few in the space of less than one meter in height.
  2. Distributions of dust particles have the same tendencies regardless of their size, if the number of dust particles per cubie cm air is represented in ratio taking the number of dust particles at any one point as the standard.
  3. The fine particles below one micron flow obliquely upward and scatter in wide space. Fine particles of dust below one micron are floating widely in the space of overhead travelling crane, too.
  4. Number of dusts on each foundry work differs widely, but their distribution has the same tendencies. As the distance from the generating points increases, the number of dusts is reduced rapidly. About ninety percent of dust particles are below one micron.