﻿ Analysis of 4 Types of Vibrating Screen Abnormal Phenomenon | LZZG

# Analysis of 4 Types of Vibrating Screen Abnormal Phenomenon

## 1. Shaker polarization

In the polarization problem, two diagonal vibrations are normal, and the other two diagonals have basically no amplitude (diagonal non-vibration), which is one of the more frequently asked questions. The reasons for this failure may be as follows.

(1) The four support points of the spring are not on the same horizontal line.

(2) The problem of the exciter of the vibrating screen.

(3) Is the included angle of the counterweight on the vibrating screen motor changed?

(4) There is a problem with the spring support. The spring force is different and the difference is large. It needs to be adjusted. Check whether the spring height is consistent when it is stationary.

(5) There may be problems with the four spring fulcrums of the vibrating screen. The free lengths of the springs are the same, but the compression modulus is inconsistent. It should be checked whether the fixed points are stable and balanced.

(6) There is a large gap between the center of the vibrating screen motor and the center of the coupling at the vibrator end in the shutdown state.

(7) Check the rigidity of the sieve body, whether it is loose, including whether the sieve plate is fixed.

(8) The angle of the eccentric block of the vibration motor is inconsistent, and check whether the individual motors of the multiple vibration motors are off-axis or faulty.

(9) If the compression amount of the spring is the same, the overall stiffness of the vibrating screen machine is not enough. You can reduce the frequency to see if the situation will be better. This kind of fault is more difficult and difficult to handle.

## 2. Torsional vibration of vibrating screen

The phenomenon of “torsional vibration” mostly occurs in linear vibrating screens for the following reasons.

(1) The direction of action of the exciting force generated by the exciter of the vibrating screen is deflected and offset.

(2) The spring damping system and different parts of the linear vibrating screen are faulty.

(3) The linear vibrating screen is not placed on a horizontal plane, and the screen surface cannot be kept horizontal.

### How to solve it?

Design and manufacture

1) Check that the screen frame is a canonical rectangle, not a parallelogram.

2) Check whether the spring supports of the screen machine are on the same level during the design and manufacturing process and whether the selected spring stiffness is the same.

3) Whether the self-synchronization between the two vibrators is normal.

4) Whether the phase angle adjusted by the main and auxiliary eccentric blocks of the vibrating screen on both sides of the same axis is consistent because it is related to whether the excitation force that occurs is consistent.

device

1) Whether the spring support of the screen machine can be installed on a uniform level, whether the current tightening amount is the same, and whether the error cannot exceed 5mm.

2) When the universal joint is installed, whether the phase angles on both sides are the same or not, other reasons should be further judged according to the specific screening machine and operating conditions.

## 3. The vibrating screen has a small amplitude

The main reasons are as follows.

### (1) Insufficient power supply voltage

If the line is not connected according to the regulations, the voltage will be insufficient, which will cause the vibration screen to have a small amplitude.

### (2) Too few eccentric blocks

You can try increasing the number of eccentric blocks to increase the amplitude.

### (3) The included angle of the eccentric block is too small

If a vibration motor is used, the angle between the eccentric blocks at both ends of the motor shaft will also affect the amplitude. The smaller the angle, the larger the exciting force and the larger the amplitude. Otherwise, the amplitude becomes smaller, so it can be adjusted by changing the angle. amplitude.

### (4) The amount of feeding is large, and the accumulated material is large

If the stone material transported to the screen surface at one time exceeds its bearing range, there will be too much remaining material or accumulated material in the screen surface and the sieve funnel, which will lead to an increase in the equipment load and affect the amplitude.

### (5) The spring design is unreasonable

When designing the spring, the net variable of the spring should be less than the height of the device, otherwise, the vibration screen amplitude will be too small; but if the net variable of the spring is too large, it may cause the body to detach from the spring.

## 4. The vibrating screen vibrates greatly

(1) Exciting force is too strong.

(2) The hardness of the damping spring is too large. If the hardness of the damping spring is too large, the buffering effect will not be achieved, and there will be a jumping problem when the equipment is running.

(3) The installation problem leads to the loosening of the anchor bolts. For example, if the ground is installed horizontally, but abnormal vibration of the screen machine occurs after a period of use, it is likely to be caused by loose anchor bolts.

(4) If the direction and power of the motor are different, it will also cause the screen machine to jump violently. (The direction of the vibration motor of the screen machine is generally adjusted when it leaves the factory.)