What is Screening Media?

When choosing your screening media, there are many things to consider. From the mechanics behind the machines used in screening, to the make-up of the screen media themselves. It is also really important to think about what is being screened, and how fine you want your output. We’re here to help you learn what screening media you need for your screening operations!

In this blog, we unpack screening media, exploring the types of media, processes, and things that affect your screening needs. We’ll also look at selecting the right screening media where you can get it.

Screening involves using mesh (the screening media) to separate materials based on their size by passing them through a screening machine such as a trommel or scalping screen. Passing materials like soil or rocks over mesh screens helps separate them by only allowing material that can fit through the holes in the mesh to fall into a bed below. This screened output can then be colleced by a conveyor and stockpiled. The larger pieces cannot pass though the media as they are too big, and will end up in an ‘oversize’ pile.

Simple right? Well, there’s a little more to it than that.

When we talk about screening media, we mean the mesh attached to the screeners themselves. The screens are really important to the process and control how well the machine will separate your material.

Screening works by adding motion to a mesh media. In a trommel, this is circular motion as the drum spins around. On a deck screener, the motion is caused by vibrating the screen. When motion is added to the surface (or screen) the material is moved about causing it to break up and fall through the mesh in a sieve like action.

Screening media can be added and swapped out on most screening machines, whether they are stationary or mobile. Here are two of the most common screening systems used today:

• Self-supporting systems - These screening systems deal with larger course materials like rocks. They must be strong enough to cope with the heavier pieces moving over the screening media. These are mostly deck screens like the one below.

• Modular systems - Modular screening systems are popular due to their versatility and lower costs. These systems are made up of smaller panels that can be changed out independently depending on your screening needs, or once they start to wear down. Modular systems also allow you to place panels with different screening sizes at various points on the machine, separating more than two material sizes at once! This is a really popular system as mesh in screeners is easily damaged but having the option to replace one panel at a time is a huge advantage. They are commonly used in trommel screens.

Apart from your screening systems, you’ll need to consider a number of things before you begin to decide what screening media is best for your use case. These include the material you want to screen, and what you hope the end result will look like.

• Screening material - First you’ll need to get a good idea about the size and shape of the input you’ll be feeding into the screener. This will help you to understand the speed at which the material will move over the screen. The quicker you screen, the faster you can make your separated outputs. But be careful, fast screening doesn't always lead to a well-separated output. To find out why check out our trommel blog here.
• Wet or dry? - Next, you’ll need to know if the material to be screened is wet, dry, or sticky. While most screening media can handle dry feeds, some media may struggle with wet, muddy or damp inputs like compost and soil. Dry products such as concrete and rock are screened best with scalping screeners whilst trommels are great for compost.
• The product - Finally, think about the type of end product you need. What final size or grade are you looking for? Will you pass the material over the screen again after crushing it? How many tons per hour will you been screening?

Now that you have a good idea about all the different types of screeners, it’s time to look at the screening media itself. Depending on if your material is wet or dry, if you’re screening soft, hard, or sandy rock, and the output size you want - you’ll need to think about the type of mesh or media that best suits your business. Below we will discover how mesh size, the material it’s made from and the kind of holes it has can all be tailored for individual applications so that you can get the most out of your screener.

Mesh sizes, patterns, and hole size

Once you’ve picked your materials, you can move on to the make up of the mesh screen itself. This is where you’ll need to pay careful attention to your screening media goals. The arrangements used for the patterns and holes that make up your screen not only determine the size of the material that will be able to pass through but also its shape.

• Size of screen holes – also known as the ‘aperture size’. The mesh hole size controls the size of the material that can pass through.
• Shape – including squares, circles, or slits. The shape of the holes in the screen can be changed to handle round, irregular, or flaky materials.
• Pattern – affects how these openings are laid out on the screen. The patterns can run in the same direction as the flow of screening input allowing more to fall through the screen. The pattern can also run against the flow, improving accuracy by slowing down the speed at which the material runs through the screen.

Mesh Materials

Next, you’ll need to pick a mesh material to use. There are three primary options for you to choose from.

• Steel – is the most commonly used material for screens. Most mesh screens use steel due to its ability to be made into any thickness & shape. Steel is also very robust and can last for a long time without needing to be replaced.

• Polyurethane – is a very tough plastic that can be molded according to your needs. It is often the best option for wet screening & it can be easily replaced without the chance of it rusting. Polyurethane is great for modular screening systems as they make great panels.

• Rubber – is best for screens that are likely to experience impacts and strikes from coarse or larger inputs like hard rocks. Rubber hardness is an important element, with harder rubbers being stiffer but lasting longer, and softer rubbers allowing for better flexibility but don't last as long.

At Machinery Partner, we collaborate only with vetted and approved suppliers, sourcing our products directly from them based on your unique business needs. We only work with high-quality, reliable materials and equipment.

Feel free to give us a call or reach out to learn more about our screening media products, materials, and options.

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Written by Toyah Warnock