Screening Problems Solved and Frequently Asked Questions

Addressing the top 5 most frequently asked questions about screening.

1. I think there’s something wrong with my screen, but I don’t know if it’s worth calling in a professional to diagnose it – what should I do?

There are some visual or field tests you can run to see if it’s worth investigating a screen further. Two easy tests are:

- Travel rate. Paint 2x oversize stones, drop them onto the top deck (loaded and running) simultaneously and observe. If they travel in parallel and come off the screen together, that is a good thing. Timing the travel is valuable to let you know if your screen is running too fast or slow, too.

- Stroke/Displacement. Take a magnetic stroke card measurement of your machine at the vibrator as well as in the corners – on both sides. You’re looking for consistency between sides primarily. Deviations of more than 5% indicate a problem you should investigate further.

You can also list the symptoms of your suspected issue and give us a call!

2. How do I make my Quality Control easier to manage from a Production point of view?

Firstly, communicate! Establish clear and open understanding with your QC staff, give them a plant tour, take a tour of their world too… it’s amazing what happens when you learn about each other’s processes. Secondly, make your screening circuit as stable as possible. Eliminate stop-gap or temporary solutions like patches and silicone on screen media.

3. How do I increase my production rate?

Diligence. Observe and even out feed points, use the right combination of screen media to only apply heavy-duty media in high wear zones and high open area media on other zones. Spend some time looking at bed depth on each deck and whether the stroke is appropriate for each application. Most of the time, some patience and trying one variable at a time to see the effect is highly rewarding.

4. My media is pegging, what do I do?

First, make sure your screen has enough stroke to clear the pegging particles. Remember, you need to manually clear the pegged particles before truly knowing if a change in stroke will prevent this. If this doesn’t work, there are highly successful self-cleaning types of media in all forms – wire, rubber, and polyurethane.

5. How do I set up my spray nozzles?

Set up spray nozzles pointing at 45 degrees against the flow of material. The resulting spray should form a continuous water curtain across the screen, such that material cannot sneak through any weak spots. Working with a screen expert can help determine how many spray bars, nozzles per bar, and spacing from the deck are required, along with volume and pressure balance. Once you see a proper nozzle setup, it's easy to apply throughout your screening circuit.

**These Frequently Asked Questions were collected from a presentation by Aggregate Territory Manager, Alex Caruana. If you'd like a more in-depth online training session for your operation, feel free to contact us.

Additionally, we have provided several resources below for your convenience.