A screen wear life problem at Kraemer Mining & Materials Inc. in Burnsville, Minn., was resolved through a field quarry equipment review and recommendation by Unified Screening & Crushing Field Representative Jimmy Georgantones, working together with Mike Strom, quarry supervisor of the Kraemer Quarry. In addition to the solution, “The Unified recommendation also proved to increase cost efficiencies for the quarry,” according to Strom.
Kramer’s 6- x 18-ft. single-deck PEP machines (equipped with three 6- x 6-ft. screens) are used for base, concrete and asphalt processing and required frequent screen change-outs due to short wear life of the screening media being used. The Stainless Steel screens were regularly being replaced, as often as every two weeks.
After the screen deck review, Unified recommended that the existing 3/32- x 2-in. openings, originally using 0.047/304-Stainless Steel wire cloth screens, be replaced with Unified’s special proprietary woven wire cloth.
Unified calls this screen media, Tufflex. Tufflex is designed for high impact and/or abrasive processes. The special Tufflex material offers greater tensile strength, ductility and corrosion resistance, noted the manufacturer.
The manufacturing process for Tufflex includes a proprietary and unique (to Tufflex) strength building process. The process creates higher tensile strength than other methods used in other screen media.
Elongated and fine grains in the wire, decrease the surface rust and corrosion compared to other wire types. The finer and elongated metal grain structure in Tufflex wire is less susceptible to breakage and has increased ductility. Also, when the wire is drawn Unified determined that there is greater consistency throughout the wire.
The result for Kraemer is that screen change-outs were cut in half and consequently production increased, wear-life doubled and overtime costs were cut in half.
“The cost is about equal to high-carbon wire and half the cost of the originally used Stainless Steel, but the savings on change-out expenses are much greater,” Strom said. “When it was time for the regular change-out, we decided to keep the Tufflex screens in because they still looked good and performed very well.”
“I got a good price and we more than doubled our wear-life,” said Strom. “I can’t complain. Think of it; half the change-outs, half the overtime, half the cost of stainless steel and double the wear life”.
Information courtesy of Unified Screening & Crushing, www.unifiedscreening.com.