文档介绍：Screening Vibrating screens
Principles --Vibrating screens save space and weight and operate on little power because the screening surface may be actuated by vibrating, gyrating or pulsating movement of small amplitude, but at frequencies that normally exceed 3,000/min.
Selection of Proper Vibration Sereen --Be sure the screen supplier knows all details of the application. The centrifugal force factor, or combination of frequency of vibration (speed) and amplitude (throw), may affect performance of any vibrating screen. Also, a correct combination of slope and direction of mechanism rotation is vital for inclined screens. Usually, the larger the opening, the greater the amplitude needed for a screen.
If the throw is too small, the material may clog or wedge in the openings. Increasing the throw beyond what is required to prevent blinding or plugging does not necessarily increase the life of the bearings and reduce screening efficiency.
Increased rate of travel permits more tonnage to be passed over the screen per unit of time. For a given tonnage, a faster rate of travel results in a thinner bed of material and high screening efficiency.
Maximum slope is reached when the material travels too fast for the fines to penetrate the ribbon of material and reach the apertures in the screen cloth. At this point an excessive amount of fine material passes over the screen with t