Alleyton Resource combines screen media to enhance wear life

By Carol Wasson| September 21, 2018

Combining modular welded-wire screen panels with synthetic media panels eliminates top-deck screening bottlenecks at Alleyton Resource’s Vox Plant. Photo courtesy of Polydeck Screen Corp.

Top-deck screening efficiency is integral to the overall performance of any aggregate plant.

When top-deck bottlenecks are eliminated, operations realize increased production capacities and more saleable product on the ground. To cost effectively achieve the latter, a new screen media equation now combines modular welded-wire screen panels with synthetic media panels. Each modular panel type is strategically located on a top deck to deliver the maximum in open area and wear life.

The endgame is greater throughput and reduced maintenance downtime for producers such as Alleyton Resource, an aggregate and ready-mix concrete company headquartered in Houston.

Too much carryback

Photo courtesy of Polydeck Screen Corp.

In addition to its 11 ready-mix sites, Alleyton’s operations include eight aggregate processing locations, material transportation, ready-mix concrete delivery, concrete pumping, and stabilized sand and slurry.

According to Brandon Genzer, plant manager at the Alleyton Vox Plant in Garwood, Texas, the deposit at the site is rather coarse. Alleyton had difficulties vacating the top deck of a wet secondary, inclined finish screen fitted with polyurethane media.

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

Recirculating loads significantly increase crusher wear and operating costs per ton, Genzer adds, sapping profit margins by sending finished product back to the crusher rather than to a saleable product stockpile. To eliminate the costly carryover issue, Genzer consulted with Kent Ropp, manager of the south Texas region for Polydeck Screen Corp.

“As regional managers, we work closely with each producer in analyzing the application and creating modular screen panel configurations that deliver the desired specifications,” Ropp says.

Arriving at a solution

The specification of the new media began by conducting about three hours of run time per sample of material.

Polydeck regional manager Kent Ropp, left, worked with Alleyton Vox plant manager Brandon Genzer to fine-tune screening performance.Photo courtesy of Polydeck Screen Corp.

“We would plug in different media to dial in our FM (fineness modulus) to just where we needed it,” Genzer says.

Ropp ultimately recommended the combination of modular welded wire screen panels with modular rubber media panels. For greater open area and throughput, Polydeck Metaldex modular steel screen media panels are placed on the discharge end of the 6-ft. x 16-ft. screen. For maximum top-deck wear life, Rubberdex synthetic rubber panels were installed to absorb the impact on the feed end of the screen.

The middle and bottom decks are outfitted with Polydex modular polyurethane screen panels.

The modularity of the Metaldex panels allows operations to apply them at the feed end, or importantly, at the discharge end where increased open area is critical in eliminating recirculating loads.

Efficient top-deck screening delivers processing flexibility and optimum plant throughput at the Vox Plant.Photo courtesy of Polydeck Screen Corp.

Tests conducted at the Vox Plant revealed that the addition of the Metaldex panels to the discharge end boosted screen performance to a 55.9 percent open area versus a 33.4 percent open area on the deck with the existing synthetic rubber panels. According to Genzer, the 1-ft. x 2-ft. welded wire panels are encased within polyurethane borders, making them much easier to handle.

“We’re getting good wear life on the panels as well, even under extended 12- to 16-hour shifts, with the first set lasting more than four months,” he says. “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.”

Other benefits

The Alleyton Resource Vox Plant in Garwood, Texas, produces construction aggregate and concrete sand.Photo courtesy of Polydeck Screen Corp.

Metaldex is comprised of AR 500 Brinell steel, Ropp says. This extends wear life in most applications.

“Welded wire delivers a higher degree of performance in strength and corrosion resistance,” Ropp says.

Another bonus, Genzer says, is that Metaldex panels offer a better scrubbing of material, effectively removing the clay content.

“We’re getting the best of both worlds now – cleaner rock at a higher throughput,” he says, adding that the plant averages 550 tph – a significant increase since the screening circuit was fine-tuned.

Metaldex was applied to a screen at another Alleyton operation, where it was largely implemented to break up and eliminate the clay content in material.

Processing flexibility is important at the Vox Plant, which primarily produces 1 1/2-in.-minus material, 3/8-in.-minus material and concrete sand. With modular screen panels, Alleyton can easily change out panels or fine-tune configurations to accommodate varying material feed or processing requirements.

“[Metaldex] offers the extended wear life of abrasion-resistant steel with the open area of wire cloth, and it’s engineered in an easy-to-handle modular design,” Ropp says.

Because its welded wire insert is embedded in a polyurethane border, it can easily be attached to a Polydeck stringer frame system with pin-style fasteners, he adds.

Carol Wasson is a veteran freelance writer for the aggregate and construction equipment industries.