Screening media is the type of material and hole configuration of the screening deck on a vibrating screen.
The most common types of screening media include:
- Woven Wire Mesh
- Polyurethane Panels
- Cross Tensioned Polyurethane
- Wedge wire
- Finger Panels
- Grizzly Bars
- Perforated Plate
- Rubber Mesh
- Flip Flow
Woven Wire Mesh
Woven wire mesh describes a weave like pattern of steel wire to form a screening medium. The steel wire can be of a high tensile grade or stainless steel.
Different weaves are available such as ‘piano wire’ which removes the horizontal wires to prevent blinding. Alternate stitching patterns are also available which can create a more level surface or provide additional flow benefits.
Cost efficiency is the main benefit of this type of mesh. It also wears well and can be used with rubber ball anti blinding decks.
The friction coefficient is high so near size or sticky material can build up on the screen surface and blind the apertures.
A favourite of the mining industry, poly panels are square foot in size and are very simple to install and remove. The plastic build material helps improve material flow and they offer great corrosion resistance.
They are secured with a pin in each corner of the panel and the perimeter is usually secured with side liners.
Price is higher compared to woven wire meshes. As with most plastics they do not do well with sharp materials and impact.
Cross Tensioned Polyurethane
Made of polyurethane but tensioned like a woven wire mesh these offer the benefits of polyurethane panels with much larger aperture sizes.
Wedge wire is made up of thick steel or stainless extrusions which are welded to form panels.
The extrusions have a taper at the bottom to encourage screened material to pass through.
Usually used in de-watering or food applications wedge wire panels are a good alternative to woven wire meshes.
Finger panels or finger screens are commonly used in the recycling industry. They involve a series of cascading laser cut steel plates which allows difficult material to move without getting caught.
Construction is considered heavy duty and cost is high relative to woven wire meshes. Due to the cascading nature of the panels, the vibrating screens built with this media need to be build with higher side walls.
Built using a series of steel section or plate, grizzly bar decks provide a heavy duty screening mesh that has no cross flow catch points.
These are used in scalping operations in quarries and mine sites.
This screening media involves a series of punched holes in steel plate.
The screening area is generally lower than woven wire with a similar cost. Perforated plate provides a flat surface which can be an advantage for low stroke or lighter applications.
Perforated plate is also easy to clean and replace when worn.
Tensioned similar to woven wire mesh or cross tensioned poly panels, rubber mesh offers an alternative build material.
Rubber is not as stretched and can be quite loose to allow for additional movement while screening which may help some materials avoid sticking or blinding.
A series of loosely connected cascading polyurethane mats creates a system known as a ‘flip flow screen’. A drive system that forces the mats to shrink and stretch which provides high acceleration forces for material.
This type of screening media is great for hard to screen materials like those found in the recycling industry.