Screen and Media Change Increases Lakeside Industries’ Production By 45 Percent.
By Mary Foster
As any owner or manager of a construction-materials company knows, time is money. When revenue relies on processing enough material to supply the customer in a timely manner – even if the customer is from within the same company – the consequences of reduced production can snowball to create fulfillment, scheduling and deadline issues downstream.
Lakeside Industries Inc., a vertically integrated company based in Issaquah, Wash., supplies its asphalt plants and paving operations with crushed gravel and sand from company-owned pits. In April 2016, the superintendent of Lakeside’s Issaquah sand and gravel pit, Pat Van Eaton, knew the scalping screens at the facility had reached the end of their useful lives. The screens were experiencing severe blinding and carryover problems, which seriously affected production.
“We had two inclined scalping screens after our primary jaw that were fed through a Y-chute,” said Van Eaton. “We’re in a wet climate, and our screens’ woven wire media kept blinding over, which led to a lot of carryover. Because they would become plugged up with sticky materials, we were having to stop and clean the screens with a fire hose at least two to three hours daily, which also made a huge mess under the screens that had to be cleaned.”
Bottom deck through material feeds the Issaquah Pit’s washing plant.
Lots of History
Lakeside Industries’ roots go back to 1952, when Rhoady Lee Sr., and his son Rhoady Lee Jr., purchased a sand and gravel and ready-mixed concrete company on the east side of Lake Washington. Over the years, as the Lee family upgraded and expanded many of its operations – including the acquisition of asphalt plants and paving operations – the company consolidated and formed Lakeside Industries in 1972.
Today, with ongoing family leadership by Tim Lee, as chief executive officer, and Michael Lee, as president, Lakeside Industries is one of the largest and most respected asphalt paving companies in the Northwest United States.
The Issaquah sand and gravel pit has been in operation for Lakeside Industries since 1954. Its scalping screens had been in service for the company for 30 years.
“The scalping screens had structural problems, the side plates were cracked and the woven wire screen cloth we were using created a lot of problems with blinding,” Van Eaton said. “So in April, we commissioned a new 6- x 16 ft., two-deck horizontal screen. At the same time, we also decided to try Flex-Mat screen cloth from Major Wire Industries.”
Lakeside Industries replaced its two inclined screens with one 6- x 16-ft. two-deck horizontal screen. The company also chose to install Flex-Mat High-Performance Screen Media from Major Wire Industries Ltd. The top deck of the new screen has 2-1/2-in. Double-Wire Flex-Mat Series D; the bottom deck has Series S Flex-Mat with 1-1/2-in. openings. The Double-Wire is designed to provide sizing of material in high-impact or heavy-material applications. The Series S removes fines and reduces blinding of wet, sticky materials while producing a cleaner retained product on the screen.
Lakeside Industries gave control of the new screen purchase to Van Eaton. He approached engineers from the screen manufacturer, who ran simulations that showed one horizontal screen could more than meet the production rates of the two older inclined screens. “We had to remodel the existing structure; there were a couple of months of steel work to build the new screen tower. And we had to change the conveyor figuration,” he said. “I also chose to use the Flex-Mat screen media because I had worked with it before in other operations.”
Van Eaton explains that Major Wire Screen Media’s Territory Manager Mark Roppo, had introduced him several years before to the benefits of Flex-Mat. “I knew that if these changes we were making didn’t work, I would be responsible. But I was 99 percent confident that the horizontal screen with the Flex-Mat would do the work of both previous screens,” he said.
In June 2016, Lakeside Industries began using 2-1/2-in. Double-Wire Flex-Mat Series D High-Performance Screen Media from Major on the top deck of the new screen and Major’s Series S Flex-Mat with 1-1/2-in. openings on the bottom deck. The Double-Wire is designed to provide sizing of material in high-impact or heavy-material applications. The Series S removes fines and reduces blinding of wet, sticky materials while producing a cleaner retained product on the screen.
Overs from the top deck and bottom deck of the Issaquah pit’s new scalping screen go to a secondary cone (essentially any material over 1-1/2-in.) for crushing. Material passing through the bottom deck is sent to a surge pile that feeds the site’s washing plant.
“With the Flex-Mat screen media in place, not only have we met our production rates from before, we’ve surpassed them. In addition, we’ve been able to fine tune the speed and stroke of the screen, which affects how the rock moves with each cycle,” Van Eaton said. He explains that the new screen with the Flex-Mat screen media in place has boosted the plant’s production from 350 tph to more than 500 tph – a 45 percent increase. “I thought it would do more than we’d previously been able to do, but I didn’t know it would do so much more,” he said. “We started it up, and by the time the material reached the last 6 ft. of the screen, it had all passed through.”
Meeting Production Needs
Because of the production increase, reduced downtime and the fact that the Issaquah pit has limited storage space for material, the plant has able to meet production needs much faster – producing in seven to eight months what it had previously produced in 12 months. The reduction in labor has freed up Issaquah pit workers to create an additional paving crew for Lakeside over the summer months.
“We’re able to use quality, reliable, trained help with our paving crews, versus bringing in untrained seasonal help and having to train them, allowing us to take on more jobs and bring in more revenue,” Van Eaton said.
“I believe this screen and the Flex-Mat screen media can produce even more than 500 tph,” he adds. “We’ll have to change the equipment behind it – we need a better feed to the primary jaw – but I think we’ll be able to boost production in the plant to 600 tph or more once we have that done.”
Information for this story courtesy of Major Wire Industries Limited.