This study deals with the screening characteristics of the mixing material of two sizes of grains, being in layer on the screen, using the Ro-Tap Shaker.
1. On the uniform size of grains, the relation of the yield ratio screened to the screening time is given by the parabolic function in the earlier period, and is represented by the following equation,
η = at^b
where, η = the yield ratio of grains screened
t = screenrng time
a = constant varying with the sort of grain and feeding rate
b = constant (0.7-1.1)
After then, the relation given above changes into the relation of the logarithmic probability function.
2. The yield ratio decreases only a little with the increase of mixing rate of smaller size of grains in the earlier period, but this effect disappears and becomes the constant ratio, in the long screened time.
3. The yield ratio decreases, in general, with the increase of the mixing rate of larger size of grain over the screen hole, and the value of b tends to decrease similary.