DRC Construction from New Brunswick faced a daunting task. They had more than 600,000 tons of rock and clay to screen after it had been stripped from a massive federal clean up site of a former steel pipe manufacturer. They needed to remove the rock and use the clay to backfill the excavation site. They were faced with two massive constraints: the end date of their contract and the harsh Canadian winter with its freezing temperatures.
New Brunswick, known for its beautiful landscapes and lush green fields, is also known for its inclement weather and traditionally sees several inches of rain per month, making the task of separating the rock from the wet clay extremely difficult.
DRC initially tried to make the separation using 3” woven wire on the top and a 1” woven on the bottom on a direct feed double decked 16 X 5 mobile screen.
“Within the first hour the screens had blinded over,” recounts John Daly, superintendent, as he describes his journey to finding Samscreen. “We approached our local screen supplier and their best suggestion was to use a finer wire and wait until it got drier.”
Neither approach was a long-term solution for DRC. Daly had heard about perforated plate or punch plate screens in the past and realized that they would help him with the impact section of his scalper deck and thought that they would help with the blinding because the surface is smooth. He searched the Internet and came across Samscreen.
“When I called Samscreen they weren’t interested in selling me punch plate, they were interested in providing me a solution,” Daly said. He was impressed by the approach of the sales team at Samscreen and how they gathered pertinent information about what he was trying to do and the problems he was facing. “They knew my machine and they knew my problem and they suggested a solution.”
The solution was Samscreen’s exclusive Grizzly Finger Deck, or GFD, which is essentially a live screen surface made up from high strength drop forged fingers (think agricultural tines) equally spaced at the opening required and divided into sections depending on the length of the screen box. The fingers, developed by Samscreen’s product development engineers, are made in the USA and are forged from high strength alloys to give extreme impact and abrasion wear resistance, are individually suspended in a proprietary elastomeric spring which cushions shock loading and ensures that the fingers act independently of each other, creating an extremely lively and aggressive screening surface which causes the soil/clay to separate from the rock, allowing clean rock to be removed from the clay.
“We removed the bolt in sub frame of the top deck and dropped the GFD sections in place. The hardest part was the removal of the sub frame which took us almost a day but fixing the GFD in place was simple, the manufacturing tolerances were great and the quality of the build evident as soon as it showed up on site,” Daly said. He also added that using the wire cloth as the screen surface they were getting on average 40 TPH of material as it required being fed through twice and in some cases three times to get clean rock, with Samscreen’s GFD, they are getting 450 TPH and the two loaders have a hard time keeping up.
“We processed the material in a little over two months going 24/7, beat our deadline easily and came in well under budget,” Daly said. “The GFD is an investment but paid off handsomely for us and made our mobile plant work like it was designed to.”