Cross-contamination of countertop colors eliminated, output doubled at KaradonIn producing granite-pattern solid surfacing material, Karadon Technologies Ltd. found that Kason circular screeners prevented jagged particles of ground plastic particles from blinding screens, a problem that plagued a rectangular screen used previously.
The round screens, by virtue of their higher throughput in a smaller screen area, upped efficiency by 200-300%. They also saved 50% in labor for changeouts and conserved valuable floor space.
The tiny, pyramid-shaped particles were hanging up in the original 8' long rectangular screen. This caused cross contamination of colors when Karadon cleaned screens to change colors every few days. The rectangular screen's slow, cumbersome changeouts further hampered process efficiency.
The Surrey, BC company replaced the rectangular screen with a 24" three-deck and recently a 40" three-deck VIBROSCREEN® circular vibratory screener from Kason, and a third 30" round screen. Time for changing colors and cleaning screens fell from one hour to 20 minutes. Cross contamination of colors was eliminated.
Karadon blends a controlled percentage of a variety of colors and particle sizes to achieve the granite effect of its high quality countertops.
To make this product, Karadon grinds up proprietary cast color blocks of polyester-acrylic material into the colored gravel-like chips. The chips are pneumatically conveyed to the three multi-deck screeners to separate the variety of particle sizes.
The 40" screener, at a flow rate of 1000 lb/hour, separates the largest sizes between 1 inch and 30 mesh into three grades. The 24" screen processes does. The 24" screen processes A 40 in. VIBROSCREEN® vibratory circular screener separates the largest particles between 1 inch and 30 mesh into over-, under- and on-size grades. the small amount remaining of the finest material at 150 lb/hour. Its three decks separate particles on 24, 40, 50 or 100 mesh screens.
Following the circular screeners, the chips are conveyed into silos, then batched and remixed to attain proper distribution of the various particle sizes and colors. The mixture proceeds into a reaction injection molding process that presses out the countertops.
'Came a Long Way'
Doug Turner, Karadon Technologies vice president research and development, says, "We've come a long way in fine tuning our screening operation for maximum throughput." Some 10 years ago, Karadon designed and built its own rectangular separation screen. Measuring 1' wide by 8' long from inlet to outlet, the unit was comprised of two or three different mesh size screens under one another.
"The rectangular screen just wasn't designed for color changeovers," says Turner. "You had to unbolt the screens from the rack, take out the screws from around the edges, take out the seal, take out the screens. Then you cleaned the screens and every nook and cranny of the frame. You put back the clean screens, bolted all back down, and resealed it.
"Now we merely open the quick-connect clamps on the circular Kason screen, pop off the deck, wipe it off, blow it down with an air hose, and put it back together. What took one hour to change colors with the rectangular screen now takes 20 minutes. Labor fell by one half."
The circular screens occupy 75% less floor space than rectangular screeners of equivalent capacity." Turner says, "We try to compact our equipment to as tight an area as possible to save in square footage costs."
Turner says the VIBROSCREEN screeners run six hours a day, five days a week, year round. Maintenance has been minimal with nothing more than a few clamps wearing out and replacing a few gaskets around the screen.
ScreenTips Newsletter Vol 14 Num 2