| 摘要 |
A method and apparatus for use in separating oversize from on size particles in a mass of particulate materials passed rapidly through a screening device includes a sloping screen mesh having sizing openings dimensioned to be larger than the desired maximum on size particles intended to pass through the mesh. The screen mesh is supported at a relatively steep slope angle and the cosine of the angle of the slope multiplied times the mesh opening size is set up to be substatially equal to the desired maximum on size particles to be passd through the screen mesh. A particle rebound shield is spaced at a distance in the range of 1.25 to 3 times the diameter of the largest particles fed to the screen above the upper surface of the screen mesh for reflecting and directing particles that bounce off the screen mesk back towards the openings therein. The material flow rapidly over the mesh because of the steep slope angle and the rebound shield insures that the largest on size particles are directed toward the openings in the mesh at least two times per linear foot of screen surfce during their travel through the apparatus to pass through the mesh.
|
