The poly ripple screencloth has been embraced today by quarry operations because it is both light and durable, combining a high open area of wire with the wear resistance of polyurethane. Unlike conventional screencloth, it is lightweight and easy to install and it has the potential to reduce downtime and increase production.
The poly ripple is constructed from a combination of crimped wires fixed by means of abrasive resistant polyurethane. Crimped wires are laid on their sides to form a diamond-shaped aperture and held in place by moulded polyurethane strips that are designed to sit over the support bars or stringers of the screen when fitted. This allows for maximum screening area uninterrupted by polyurethane. The aperture formed by the crimped wires (which are touching, but not fixed together) enables the wires to vibrate independently, as they have not been woven together.
The poly ripple is fitted to the vibratingscreen in the same manner as woven wire, that is, supplied with hooked edges that will fit all makes of side clamps and cambered decks. When fitted to machines with centre hold down bars, the poly ripple is made to suit, complete with already cut boltholes.
Poly ripple is considered superior to woven wire and wire ripple screencloths. The total surface of poly ripple is flatter than that of woven wire; therefore, the product passing down the screen is not constantly wearing on the crimps of the wires, as happens on woven wire. Poly ripple is also longer lasting than wire ripple; the twill wires in wire ripple are woven down the screen and are more likely to wear out long before sizing or cross wires.
Unlike conventional woven wire, poly ripple screencloth is not impaired by pegging or blinding. The crimped wires vibrate independently of the screen unit when the screen is active and the vibration of the poly ripple allows particles to pass through the aperture and minimises the build up of fine particles on the wires. The poly ripple structure therefore promises a clean screencloth surface and optimum open area through the screening process.
Poly ripple screencloth is also adaptable, as it can be constructed within an area of solid polyurethane as a blank impact zone. The impact zone will prevent wires from opening up if the drop height is too great or where the feed onto the screen is too harsh and prematurely wears out the screencloth. Where the worn area of the mat is to be replaced, it can be blanked off, ensuring that the screening area is not reduced unreasonably.
The general rule for the correct wire diameter for a given aperture is that it is the next gauge down from what would normally be supplied in woven wire, eg 12mm aperture in 4mm wire, 6.3mm aperture in 2.5mm wire, etc.
THE SPLIT POLLY RIPPLE SCREENCLOTH
The split poly ripple screencloth is constructedby splitting the normal apertures with straight wires to form a triangular screeningenvelope. With normal ripples and poly ripples, the smaller the aperture, the smallerthe wire diameter used to form the aperture.However, the resultant ratio of wire diametersto apertures can be greatly increased with this screen. With a split poly ripple, the screencloth can use a 3.15mm wire to form a 2.5mm aperture (compared to a normal ripple or poly ripple screencloth where only 1.25mm wire would be used to form a 2.5mm aperture). This is achieved by crimping 3.15mm wire with 5mm wheels, and then ?splitting? the aperture by inserting a straight wire of 3.15mm. This results in a 2.5mm screening envelope with 3.15mm diameter wire.
The key benefit of the split poly ripple is that it can address the wear problems encountered in using finer aperture screens because of the tonnes per hour or lump size of the feed.
DISTRIBUTOR
The Locker Group specialises in the manufacture of wire mesh screens, especially for sand, gravel and aggregates quarries and in construction and recycling sites for rubble screening, site clean-up, aggregate sizing and reclamation of solids and contaminated products. Its product range is also popular in other industrial applications for filtering, flooring and access walkways.
The Locker Group?s industrial wire mesh screens are made of woven or crimped wire from stainless steel, galvanised iron, polyester or carbon steel and are employed in numerous quarries and mines around thecountry. A recent trial of The Locker Group?sown range of split poly ripple screencloth indicated that the split poly ripple wire screen has improved dramatically on the performance of woven wire, ripple wire and now poly ripple wire screens (see inset).
Source: The Locker Group