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The screening process is a fundamental step in aggregate production, because it allows the separation of materials in different sizes and ensures the quality of the final product. However, many companies face challenges performing this work properly, so our purpose is to help you to achieve this goal.

The first step to achieve the best result is to choose the right equipment, based on the type of material to be screened and the intended grain size. There are different types of machines available in the market, but Athox operates with multi-slope modular screens, inclined screens, dewatering screens, and more recently, high-frequency screens, whith high-speed vibration between 3,000 and 4,500 rpm, induced directly in the classification screen media, allowing for greater stratification and separation of products.

This improves the efficiency at high performance rates of fine materials when compared to conventional screens. This equipment offers the ideal gradation control in fine recovery and dry applications for fine particles size, between 10 and 0.3mm, and operates with inclination between 30 and 40 degrees.

“Screening is a dynamic process which involves many elements, such as inclination, amplitude and frequency of vibration. It is important that the equipment is properly adjusted to ensure efficiency in separating the material, otherwise it can result in incomplete process, affecting the quality of the product,” highlights Paulo José Alves dos Santos, director of engineering and innovation at Athox.

Another important factor is the maintenance of the screen. “This procedure must keep a regularity, to ensure proper operation and avoid unexpected failures. The maintenance must include cleaning the screen, checking the wear, the tensioning of the screens media, and replacing damaged parts,” explains Paulo. Lack of maintenance can lead to decrease of screening efficiency and affect the final quality.

Select the screen according to the type of material
The choice of the right screen is also a crucial factor for high-quality rating. It should be selected on the basis of the type of material screened and the particle size required, as well as produced from high-quality and durable raw materials to ensure endurance.

In this regard, the screens media need to be correctly installed and properly tensioned to ensure efficient separation of the material. A poorly installed screen media can, for example, result in an incomplete separation of the material, interfering in the result of the finished product.

Why high frequency?
The efficiency of the screening process is being increasingly improved through the use of modern technologies such as high-frequency screens, that are able to sort materials into smaller sizes in dry processes, reducing waste.

In addition, the use of automation systems can improve greater efficiency of the screening process. They control and keep track of vibration speed and frequency, which can range according to the material and particle size desired.

Dewatering Screen
Following the technologies portfolio, Athox also produces the Dewatering Vibrating Screen, that performs the functions of dewatering and delamination of materials with fine granulometry. To carry out this process efficiently, support the high layer of material and the dynamic effect caused by water agitation, it has a specially reinforced structure and vibrators.

The machine has an upward inclination, between 5° and 7°, and linear movement. These elements allow it to be widely used in mining and natural sand extraction, for example. It has a modular bolted screen media, made of polyurethane, for maximum dewatering of the product, high wear resistance, and efficient sand classifying. Besides, it is easy to maintain, and has a replaceable polyurethane lining on the side wall of the screen, which reduces the contact of the material and the side plate, increasing the machine’s useful life. The rotating elements are protected and meet NR-12 safety standards.