When you eliminate top-deck bottlenecks, you increase production capacity and put more saleable product on the ground. Read about how Polydeck assisted with a higher level of efficiency in a cost-effective way.

If you’re running an aggregate plant, then you know that the efficiency of your top-deck screens is critical to your operation’s overall performance. It’s a simple formula: When you eliminate top-deck bottlenecks, you increase production capacity and put more saleable product on the ground. But how can operators achieve that level of efficiency in a cost-effective way?

Polydeck’s answer to this question is a screen media equation that combines modular welded-wire screen panels with synthetic media panels. Each modular panel type is strategically-located on the top deck to deliver maximum open area and superior wear life. For operators, the result is greater throughput and reduced maintenance downtime = more profit and fewer expenses.

Polydeck partner, Alleyton Resources, is an aggregates and ready-mix concrete producer headquartered in Houston, TX. Their operations include 11 RMC sites and eight aggregate processing locations, and they provide material transportation, ready mix concrete delivery, concrete pumping, and stabilized sand and slurry to their customers.

Brandon Genzer (Plant Manager at Alleyton’s Vox Plant in Garwood, TX, at the time) was dealing with coarse deposits at the site as well as difficulties vacating the top deck of their wet secondary, inclined finish screen, which was fitted with polyurethane media.

“The screen is being fed 2-1/2-in.-minus material,” he explains, “We had a lot of carryover of 1-1/2-in. material, which created unnecessary recirculating loads going back to the crusher.”

This was a huge problem for their operation because recirculating loads significantly increase both crusher wear and per-ton operating costs. It was sapping the facility’s profit margins by sending finished product back to the crusher instead of to the saleable product stockpile.

To eliminate this costly carryover issue, Genzer consulted with Polydeck’s manager for the South Texas region at the time, Kent Ropp. “I work closely with each producer in my area to analyze their application and create modular screen panel configurations that deliver the desired specifications.”

Ropp worked with Genzer to specify the new media by conducting several hours of run time for each sample of material. “We would plug in different media to dial in our FM [fineness modulus] to just where we needed it,” Genzer recalls.

Ropp ultimately recommended a combination of Polydeck’s high-performance products. For greater open area and throughput, Polydeck’s METALDEX™ modular steel screen media panels were installed on the discharge end of the facility’s 6-ft. x 16-ft. screen. To absorb the impact on the feed end of the screen, RUBBERDEX® synthetic rubber panels were installed for maximum top-deck wear life. The middle and bottom decks were outfitted with POLYDEX® modular polyurethane screen panels.

The METALDEX™ panels offer open area that equals or exceeds traditional wire cloth of the same aperture and wire diameter. In addition to greater open area, the modularity of the panels allows operations to apply them at the feed end or, more importantly, at the discharge end where increased open area is critical in eliminating recirculating loads.

Tests conducted by Ropp at the Vox Plant determined that the addition of Metaldex panels to the discharge end boosted screen performance to 55.9% open area over the 33.4% rating they achieved with the previous synthetic rubber panels.

“We’re getting good wear life on the panels as well,” Genzer reports, “Even under extended 12- to 16-hour shifts, the first set lasted more than four months. When we extend hours, we check the screens at the end of every shift. If need be, the crew can change out panels in a matter of minutes, and we’re back up and running.”

According to Ropp, the key to METALDEX’s greater wear life is that: “It’s comprised of abrasion-resistant AR 500 Brinell steel, which extends wear life in most applications against that of standard wire cloth. Welded wire simply delivers a higher degree of performance in strength and corrosion resistance.”

Another bonus for the Vox plant is that METALDEX™ panels scrub the material better, removing the clay content. “We’re getting the best of both worlds now—cleaner rock at a higher throughput,” says Genzer, adding that the plant averages 550-tons per hour, a significant increase since the screening circuit was fine-tuned. Alleyton has since implemented a METALDEX™ screen at another operation to help break up and eliminate the clay content in their material.

Because processing flexibility is important at the Vox facility—which primarily produces 1-1/2-in.-minus material, 3/8-in.-minus material, and concrete sand—the modularity of the screen panels enables them to easily change out panels or fine-tune configurations to accommodate varying material feeds or processing requirements. The borders of each 1-ft x 2-ft welded wire panel are encased in polyurethane, as well, making them much easier to handle than large wire cloth sections.

“METALDEX™ is another groundbreaking screen panel design from Polydeck that enhances the range of screen media solutions and help our customers beat their production goals,” says Ropp. “It offers the extended wear life of abrasion-resistant steel with the open area of wire cloth, and the modular engineering allows for easy handling and simple attachment to Polydeck’s stringer frame system.”

Eliminating screening bottlenecks is essential to maximizing throughput on top-deck screening, which is, in turn, critical to optimal plant performance. At Alleyton Resources’ Vox Plant, Polydeck’s innovative combination of welded wire and synthetic media panels was the precise formula to solve their screening problems.

Polydeck’s NEW METALDEX™ VR

In 2020, Polydeck launched a new product offering- METALDEX™ VR. Polydeck’s new modular wire screen solution integrates with our PIPETOP™ stringer system. Perfect for dry-sizing applications where more open area and efficiency is required, METALDEX™ VR is ideally installed on the discharge end, where it provides longer wear life and better throughput, and its unique, diamond-shaped pattern eliminates blinding and plugging.

Vicdom Sand & Gravel knows full well that producing and washing aggregate is tough on equipment. The family-owned, third-generation company has been producing stone, sand, and gravel for more than 40 years in Uxbridge, Ontario, Canada, a 30-minute drive northeast of Toronto.

Vicdom’s management also knows that unnecessary downtime comes at a high cost. Until recently, the company had been encountering periodic wear issues with the 5’ x 7’ wire screen media on its two-deck, 5’ x 14’ Dillon wash screens. The screens were being used to produce +5/8" over the top deck, 9/16"-1/4" over the bottom deck, and 1/4" chip through the bottom deck. Although the screens had decent wear life and met production requirements when in operation, once they became damaged, they had to be completely replaced.

“We’d get one hole in the feed zone and have to change the whole screen, even though 75 percent of the screen is still in good shape,” says Victor Giordano, assistant manager at Vicdom, and grandson of late Vicdom co-founder Vic Giordano. “A $500 screen was now garbage.”

The larger cost stemming from the screen replacements was the downtime that came with switching out the 5’ x 7’ screen media, which Giordano says cost his operation between one and three hours of downtime each time they needed to be replaced. So, when Alex Caruana, Polydeck territory manager for Central and Atlantic Canada, explained that the company could save money and reduce downtime in its operation by retrofitting its wash screens with a modular snap-in system, Giordano wanted to learn more.

“Alex brought a diagram and did a good job in explaining what we had before with wire mesh and what we could have with Polydeck,” Giordano says. “The biggest knock on rubber and polyurethane is that it doesn’t have enough open area like wire mesh, but he showed that you didn’t lose any open area.”

Caruana showed Giordano he wouldn’t lose any open area by using a very simple, but effective method.

“What I typically do for a plant when they're considering one or more decks is very simple. I lockout, jump on the screen or take a picture, and just count the openings. I know how big the openings are, because I’ve measured them, and that also allows me to take into account any obstructions like bucker bars, side clamp rails, any diverters, any bolts and other things of this sort. That allows me to show the customer that with their current wire cloth, they have ‘X’ open area, whatever ‘X’ may be”, Caruana explains. “And then, I am able to show them that in their application, using our media, your open area would now be “X+,” and that's their new open area number.”

In many cases, this comparison is a big eye-opener for producers.

“Even with wire cloth, they may not have had all the open area they thought they did,” Caruana explains. “Just imagine a piece of mesh screen in front of you. It's unobstructed, and its cataloged open area, or book value, might be 65%. It looks very attractive. But when you actually put it in place, there are machine parts underneath it. So, you don't really have 65%, it might be 48%. Whereas, synthetic media is not the same. When synthetic media is giving an open area, that is the gross and net number. When installed, it still has that open area. If somebody tells you that you've got 48%, then that's the number in place. So, by me doing that comparison for people like Victor at Vicdom, they have that information available to them and they can make a more educated selection.”

Vicdom decided to change over one of its wash decks with a modular snap system using 1’ x 1’ Polydeck polyurethane panels with 1/2” square openings on the top deck and roughly 1/4” openings on the bottom deck. Giordano was impressed with the results.

“This year we changed two panels, total, on the conversion,” he says. “We would have normally changed five or six entire screens. Instead, we changed two panels that cost $90 Canadian each for $180 in a year. The efficiencies are good, capacity is good, and downtime is amazing,”

Vicdom has now outfitted all four decks on its two wash screens with Polydeck’s modular snap-in system using 1’ x 1’ polyurethane panels. The second wash screen has 5/8” openings on the top deck and roughly 1/4” openings on the bottom deck.

The reduction in downtime with screen media change-outs isn’t the only reason Vicdom enjoys working with Polydeck. Giordano says that Caruana’s level of professionalism has been a big selling point, always making himself available to assist with any issues that occur on-site.

The company had a processing issue last year with the first conversion, so they called Caruana to discuss the issue.

“He asked, ‘Are you sure your eccentrics are running downhill?’” Giordano recalls.

So, Giordano checked with his maintenance crew and it turns out they had done some work previously that day and accidentally re-wired the motor backwards on the screen causing the eccentrics to run uphill.

“We fixed the wiring, popped the stone out and it was working again. With his knowledge we were able to fix that issue right away,” Giordano says, adding that he has a great appreciation for the technical knowledge Caruana brings with him to the job site. “I don’t see a sales guy. I see a guy with a lot of pit experience now in sales, and that helps.”

Thinking about a conversion?

Polydeck has a team of professionals and more than 40 years of experience to help you optimize your screening performance while minimizing downtime.