It’s widely accepted to default to standard square aperture shapes for screen media, but Polydeck has proven that varying aperture shapes can be a simple and effective upgrade to increase aggregate screening results across a variety of applications.
Tried and true performance and sticking with what you know works is often a hallmark of business decisions. You choose what you were taught works, and what you know works. Many aggregate plant managers and other mining operation managers know that in order to see the considerable cost or efficiency improvements, the changes they would have to make to their operations are often time-consuming and costly. However, Polydeck screen media, with its varied and customizable aperture shapes, can create significant throughput and cost improvements with very little effort required to make the change.
Historically, square apertures are the standard in screen media and what most plant managers are familiar with. You know it works, you’ve used it before, you see very little reason to change. However, we have seen operations increase their screening efficiency by as much as 10 to 20% by using varied aperture shapes in their operations. The change to Polydeck screen media is one that offers proven increased wear life, reduced costs, increased throughput and efficiency, and comes with our Wear Life and Labor Savings Guarantee. Making the change to aperture shapes better suited for the materials you are screening is a cost-effective upgrade that will significantly boost your operation’s bottom line, and the results are clear in four key areas.
1. Primary scalping and secondary screens can benefit significantly from elongated slots or VR aperture. Scalping screens are handling a considerable amount of processing work. We scalp off the top size particles for the secondary crusher and expect the bottom deck to take out the natural fines or produce base. The Polydeck team has seen scalping screens set up to make a 3/8” cut on the bottom deck, a tall order when the material gets introduced to the deck halfway down because the top deck was overloaded. This is a perfect situation to use elongated slots or VR’s to get a boost in open area and throughput capacity. The faster the top deck screens material, the more efficient the lower deck will be. The end result will be similar to getting a bigger screen due to the increased open area provided by the varied aperture shape.
2. Sizing for crushers can benefit from non-square aperture shapes. If an operation is sizing for crushers and the top size cut on the deck isn’t particle shape critical, you will realize an efficiency improvement in both screening and cone crusher utilization. Better sized and cleaner crusher feed will lower fines generation significantly.
3. Non
square aperture screen media can improve efficiency significantly for
bottom deck and fine screening areas. Screening fines efficiently has
always been an issue for aggregate producers. In cases where a “clean
chip” or another small sieve size aggregate is sought, a longer slot
length (with or against flow), a VR or even an SVR style aperture may
improve screening efficiency and the cleanliness of the material. Slots
have an advantage in picking up open area for screens. Screens with
faster travel rates, such as incline screens, see the largest
improvements. Switching to non-square aperture for bottom deck and fine
screening will produce results that similar to gaining more screen deck.
4. If particle shape isn’t critical, consider varied aperture shapes. Certain plants are not as susceptible to particle shape issues and can utilize various aperture shapes throughout the plant. Plants with impact crushers often have fines issues and cubical particle shapes, a perfect situation to use higher open area apertures. Alluvial deposits often produce a rounded particle shape and could benefit greatly from various aperture shapes.
Whether your operation is exploring opportunities for cost and throughput improvement, or simply seeking to create an optimal setup for end result quality, consider the shape of your screen media panels. While square aperture has traditionally been the benchmark of screening operations, varied shapes have proven to create increases in efficiency, improved final material results, and reduced operations costs. Polydeck’s screen media solutions can be customized to suit the needs of your operation and end user requirements. With thousands of panel configurations and variations available and the ability to customize for your needs, we’ll be able to create a solution that is guaranteed to improve the profitability and efficiency of your screening operation.
Written by Tod Eberle, Director of Aggregates for Polydeck.
