The screening equipment screen blinding and solution

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Most screener equipment could meet the screen aperture blinding problem, the blinding problem always reduce total screen mesh area,
then decrease the screening and separation capacity.
There are mainly following reasons cause the screener mesh aperture plugging:
1.The bulk material size and shape is near the mesh aperture size, the particle material is hard to escape from the aperture when it fall
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For this case, selecting one proper screening aperture screen mesh is important.
2.The material is moisture with water or oil, it is sticky, and the little particle adhere to the inside of screen aperture.
If meet this situation, we add one process to reduce the moisture of the particle material.
3.There a are too many fibroid material in the material flow, the fibroid always twine on the screener mesh.
For the fibroid material, selecting one screening equipment types is very important, we need try the best to avoid the vibratory of screen
mesh, the rotary or gryatory motion screener is one good choice.

Vibratory Screen Cleaning Methods

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General

Screen blinding always happends when the screen mesh openings are blocked or closed by the  material  which  is  being screened. Near size particles become trapped or build up on the wires effectively blocking the screen openings preventing further material from passing through the screen. And some  blinding  because  the   material  features  such  misture   and stickiness,  and some because there are  too many fabric, This is  a common screening problem which is easily fixed  with screen cleaning devices. following will review the most common methods of screen deblinding.

1.BALL TRAYS
Rubber or other spring balls are the second most utilized screen cleaning method, but can only be used for dry screening. The rubber balls are generally 20mm-50mm diameter and  are  supported by a  second  coarser  mesh  two  inches  below  the classifying screen mesh. Higher vertical separator motion is required to activate the ball  cleaning action  because the balls must be thrown up against the bottom of  the  screen, in this  case ,the  rectangular gyratory screener have long  stroke  and strong force which could let ball jump.

2.SLIDERS
The most common self cleaning device is the “SLIDER”. Slider Rings are loose rings which slide directly beneath the screen surface on a slider support surface, normally a perforated metal plate. The rings are bounced vertically into the screen mesh by the vertical motion of the separator as they travel radially around the screen. The sliders are activated by the motion of the separator with out additional driving force

3.SANDWICH SCREENS
Sandwich screens are made by bonding a classifying mesh to the top of the screen tension ring and a coarser support screen mesh to the bottom of the ring. This creates a sandwich with screen cleaning devices floating between meshes. This sandwich construction improves cleaning action, decreases maintenance costs, and decreases noise levels.

4.TOP SIDE ROTARY BRUSHES
The top side rotary brushes are exceptional for clearing fibrous materials which tend to mat on top of the screen and block the mesh openings. The rotary brushes move around the screen diameter propelled by the  vibratory  motion  of the  separator, no additional driving motors are required. The brushes ball up the fibrous mat above the screen to expose screen  the  openings, the fiber balls are then discharged from the top of the screen and out the spout.

5.WATER SPRAYS
Water  sprays  clear  screen  mesh  openings, help  eject  solids, and  keep  slurries  from  drying out  and  building up  inside separators. Another spray advantage is there is no contamination from slider, ball, or brush  materials. The  disadvantages  of liquid sprays are cost and potential dilution of products.

6.Metal percussion

This is method is mainly adopt on the rotary screener, the Metal  hammer  rotate  follow  with the  rotary  screen  drum, and  the hammer knock on drum casing periodly.