Often, we are asked about vibrating screen media types when discussing our vibratory screening equipment with producers. It’s no surprise that this is a very common question due to the fact that there are so many screen media options to choose from.
In this blog, we will review in depth the basic vibrating screen media types, and the pros and cons for each type.
Before we start, let’s quickly review the purpose of our screening equipment. The purpose of a screen is not to make product. That’s right, the product has already been made once it hits the screen deck by nature or some crushing process. The role of a screen is to separate the already made product into the appropriate size in an efficient manner. For this reason, the selection of the media to do this critical job is crucial.
It’s important to note that there are a few questions to ask which will help point us in the direction of selecting the right media for your screen. The final media choice might well be at the end of a journey of a continual improvement process relative to media choice. Our purpose here is to get started by looking at generalities in media choice. We need a place to begin our journey. Here are a few queries to get you started:
Note: Our topic here is media. The physical characteristics of the actual screen will influence the performance of the screen and may supersede media selection. For example, a screen fed with too much material will have a bed-depth which results in some of the material never reaching the media for separation. Media selection is not a substitute for proper screen feed parameters.
In addition, ask your vibrating screen manufacturer for a vibration analysis before and after installing the screen media.
Wire cloth or wire mesh has been used for screen media for decades in a wide range of applications. The product is available in various alloys such as stainless steel, oil tempered, and high-carbon options with a number of weave types to choose from. Wire cloth is most often attached to the screen via side tensioning.
Perforated Plate / Punch Plate
Perforated and punch plate is steel plate that has been laser or punch cut. Plate is ideal on top (and sometimes middle) deck applications due to its abrasion resistance and its ability to withstand the high impact that large rock creates. Plate is commonly used on scalping screens, after raw materials pass through primary crushers.
Rubber screen media is similar in application to metal perforated plate. It is ideal for high-impact applications, and can be used in wet or dry circuits.
Polyurethane media is created using the open cast method or by injection-molding. This media offers a very durable solution that comes in multiple panels instead of one large screen panel. This can allow worn areas to be replaced quickly without having to change the entire screen deck. Polyurethane is ideal for high wear areas in both wet and dry processing applications.
Hybrid media, which is urethane-encapsulated wire or wire held in place with rubber or urethane strips, combine the open area benefit of wire cloth and excellent wear-life characteristics of polyurethane.
Screening your material can arguably be considered more important than crushing it. If the screen is not performing, your crushing will be impacted by high recirculating loads and the crushing of already produced product. Optimizing your screening process needs to be at the top of your to-do list. Building a relationship with your dealer, vendor, or manufacturing representative can greatly help you select the right screens for your operation. In addition, they can also share plant experiences with similar material characteristics and weigh efficiency gains, screen media life, and cost per ton of finished product.
Don’t be afraid to step out of the box and try something new. Try testing ideas with your screen media vendor.
Finally, it’s always a good idea to listen to your operators as they can share past experiences and trials. What do they see as challenges and concerns with media changes? Nobody knows as well as the people running the show. Bring them into the conversation early to speed up the decision process.