There are many kinds of vibrating screen in the mineral processing industry, which can be divided into round vibrating screen and linear vibrating screen according to the moving track of materials. But not all mine owners know their differences, and still wonder how to select the types of vibrating screen.
Classification of vibrating screen
According to the moving track of materials, vibrating screen can be divided into fine screen, round vibrating screen and linear vibrating screen.
Fine screen is barely used in ore grinding stage, so we do not mention it here. There is no principle differences between round vibrating screen and linear vibrating screen in style and structure. The screening purpose is achieved by the screening of screen surface, but the different moving tracks have influence on the screening purpose.
Working principle of vibrating screen
1. Round vibrating screen
The motor vibrator drives the eccentric vibration exciter to rotate in a high speed through v-belt, which produces a large centrifugal force, and stimulates the screen box to produce certain amplitude of circular movement. The oversize material starts the continuous throwing motion under the impulse of screen box. So, those material whose particles is less than the screen mesh is classified.
2. Linear vibrating screen
The vibrating motor is used as the source of vibration, so that the material can be thrown up on the screen, and moves forward in a straight line. The material is sent to the feeding port of vibrating screen evenly, then screened into multiple sizes of oversize material and undersize material, which is discharged from the respective discharge port.
Differences of vibrating screen
1. Moving track of vibrating screen
The material moves in a round on the round vibrating screen, while the material moves forward in a straight line.
2. Vibration exciter of vibrating screen
The vibration exciter of round vibrating screen is a shaft, which is also called single-shaft vibrating screen; the vibration exciter of linear vibrating screen is composed of two shafts, which is also called double-shaft vibrating screen.
3. Plugged hole of vibrating screen
The material moves in a parabolic circular trajectory on the screen surface of round vibrating screen, which makes the material disperse as much as possible, improves the leaping ability of material.
4. Installation of vibrating screen
The linear vibrating screen is equipped with small screen slope and lower height of screen, which is convenient to install.
5. Screen slope of vibrating screen
According to the particle size of the material, the round vibrating screen can change the screen slope, thus changing the moving speed of the material along the screen surface and improving the processing capacity of vibrating screen.
6. Equipment material of vibrating screen
Generally, the round vibrating screen adopts thicker plates, and the screen box is made of manganese steel, which can resist the impact force of materials in the screening process. Otherwise, the linear vibrating screen is made of light plate or stainless steel plate.
7. Application of vibrating screen
The round vibrating screen is mainly used in mining, coal, quarrying and other mining industries, especially for those screening materials with big screening proportion, large particles and high hardness.
8. Processing capacity of vibrating screen
For round vibrating screen, because the vibrator is decorated at the top of the screen box, so the longer axes of the ellipse on the both ends of screen box is showed as flgure-eights, so its top of feeding port is in the direction of discharging, which makes material spread out rapidly, and its top of discharge end is against the discharging direction, which reduces the movement speed of material, and makes the difficult-to screen material through the screen easily. Besides, the arc-shaped screen surface increases the effective area of the vibrating screen, thus improving its processing capacity.
For those difficult-to-screen materials, the round vibrating screen can turn the main shaft so that the vibration direction is opposite to the moving direction of material. The moving speed of material along the screen surface is reduced (the screen slope is same as the rotate speed of main shaft), then the screening efficiency is improved.
9. Environmental protection of vibrating screen
The linear vibrating screen can adopt a fully closed structure without dust spillage, which is more beneficial to environmental protection.
All in all, selecting round vibrating screen or linear vibrating screen is mainly based on the type of materials, application and screening purpose. Mine owners must to decide the types of vibrating screen according to their production requirements.