What reasons lead to material accumulation phenomenon of vibrating screen?

Some customers said material accumulation phenomenon occurred in the use process of vibrating screen, according to many years of analysis experience, the reasons can be summed up in four aspects:
1.There is a problem of vibrating screen mesh selection, too small mesh will cause a low rate of material passing through the mesh.
2. Check whether the ground level of the vibrating screen is flat or not, besides,high material inlet will affect the material running track, resulting in material tilting to one side.

 

3.Check whether the screen mesh and outlet are horizontal or higher than outlet or not, under normal circumstances, it should be horizontal or 6mm higher, the design is not the same according to different material discharging outlet.
4.There is a problem on the vibration motor angle adjustment, improper angle adjustment of vibration motor will cause material accumulation, if the angle is small,the material will spread outward quickly on the sieve surface,while if the angle is large, the spreading speed will be slow. If you have strict requirements of screening accuracy, the angle can not be too small so as not to affect the screening precision. In general, the vibration motor angle of the vibrating screen is 45 degrees when leaves the factory.
Users can also change the vibration motor angle to 100 degrees according to the the special requirements of the material ,and then material will be concentrated to the central screen mesh. 

How to choose the suitable vibration motor for the vibration machine?

Vibration motor has many types and models with a wide application,it is usually applied with the feeder, vibrating screen combination. The vibration motor is very important in the vibration machine. It directly determines the working efficiency of the vibration machine.The vibration mechanical vibration motor selection steps are as follows:
A.According to the operating requirements, confirm the required vibration of the frequency (r/min) and the amplitude Ym (mm).
Such as the six vibration motor (n=960r /min) can drive the vibration chute, vibration feeder, vibration mill, vibrating screen etc.
B.According to the structure of the vibration machine itself, get the vibration weight G (kg) and calculate the required vibration force Fm (N) .
C.According to the vibration of the operation to get Fm, you can get the model of the vibration motor, please pay attention to the exciting force FH is larger than Fm.
D.Design the overall structure, and calculate the actual vibration parameters, after the calculation, if the vibration motor is too large or too small, motor model should be re-selected.
E.Design of vibration isolation system. 

Improve dry or wet screening efficiency of vibrating screen

Following methods can improve screening efficiency of vibrating screen:

1.For dry screening,we should strictly control the water content,for material with high water content,please consider screening with ingredients.
2.Reduce the of plugged hole,we can consider using the self-cleaning sieve plate,for example,for spring rod type screen mesh surface,we can add a prevent blockage device below the screen.
3.Improve the aperture percentage,high aperture percentage is beneficial to improve the screening effect.
4.Adjust the feeding way.Material can be fed according to the sieve surface width and ensure the sieve surface can be fully utilized.
5.If possible,please consider the dip angle of the screen machine,suitable angle is beneficial to reduce the thickness of material and achieve thin material screening.
6.For circular vibrating screen,we can consider adjusting the balance weight to improve the screening effect.
7.If possible, coarse screening before feeding material.
8.If possible, we can adopt wet screening,it’s the most effective way to improve the screening effect. 

What factors affect vibrating screen purchase

Please consider the following factors when purchase vibrating screen
A.Physical property of the material
Including material particle size, shape, moisture content, bulk density ,property ,etc. When the particle size is fine and mesh size is small, the screen efficiency will be lower, we need to select larger model for same capacity; when the moisture content is big, in general, the screen efficiency will be lower. However,if the mesh size is bigger, the influence of moisture content will be less; when the material with corrosion property, the material contacts parts usually need to be SUS 304 or whole machine is SUS304.

 

B.Screen surface character and structure
In general, if the material do vertical movement on the screen surface (such as linear vibrating screen,etc), the screen efficiency will be higher and the capacity is larger. If the material do reciprocating movement on the screen surface (such as gyratory screen,etc),the screen efficiency and capacity will be lower.
For certain material, the screen efficiency and capacity rate are determined by the mesh size. The screen efficiency is determined by the screen surface length, the longer screen surface length is, the higher screen efficiency will be; the capacity rate is determined by the screen surface width, the bigger screen surface width is, the higher capacity rate will be. 
C.Production condition
The screen efficiency will be lower when the load on the vibrating screen is big.Uniform feeding material also has a big influence on the screen efficiency. (For this question, PK Machinery designs a distributor above the inlet of vibrating screen to achieve uniform material feeding).
Only when we take all above factors into consideration,will we get a suitable vibrating screen that can meet our production efficiency. 

What's the Special Role of Vibrating Screen Bouncing Ball?

When the vibrating screen works, have you ever noticed that the bouncing balls beat up and down on the sieve mesh? Why this phenomenon occurs on the sieve mesh? What's special role of bouncing ball? Today we will take a brief look.
These bouncing balls are an essential part of vibrating screening machines.Its role is beating the sieve mesh up and down avoid adhesion material blocking the sieve mesh which can improve screening efficiency and accuracy.

Bouncing balls are generally divided into different diameters: φ10, φ15, φ20, φ25, φ28, φ30, φ40, φ50, φ60 and so on, commonly used ones are φ25 and φ28 , φ40, φ50and φ60 mainly used for mine vibrating screen.
According to the material,bouncing ball can be classified into several types: rubber ball, silicone ball, PTFE ball bouncing, according to different materials of bouncing balls, the application and function is also different.
Natural rubber bouncing ball：it is suitable for general material screening process;
Silicone bouncing ball：good elasticity., mainly used for food, medicine and other materials screening;
PTFE bouncing ball : It can soak in the oil , mainly applied to oily liquid materials screening.
The bouncing balls should be selected based on different material properties to meet customer requirements in different conditions. Though bouncing ball is a small accessory, it is the key to solve the problem of screening.