Aggregate and quarry handling operations require equipment that can perform reliably for high volume production in dirty, dusty and corrosive environments.
That is the situation at Edwards Sand & Gravel, a six-decade-old company that extracts and sells high grade aggregate to customers near its main quarry in South Sterling, Pennsylvania, USA.
Moving crushed sandstone out of the quarry requires two Eriez model 75B vibratory feeders, which are positioned over a conveyor belt in the quarry tunnel. The units function as pile discharge feeders and meter minus 70mm stone to an inline belt conveyor. The 75B vibratory feeder has a feeding capacity of up to 315 tonnes per hour, representing a 20 per cent improvement in feeding capacity over previous models.
{{quote-A:R-W:300-Q:"Eriez is recognised as a leading authority in separation technologies."}}The Edwards sandstone quarry sits on 96 hectares and has been in operation for about 25 years, according to president George Edwards Jr, the son of the company’s founder.
“My dad started the company back in the 1950s and we now have 40 employees, including my two brothers,” Edwards said. “We have always been in the sand and gravel business and have developed a strong customer base.”
The South Sterling sandstone quarry, which produces 680,000 tonnes annually, has about 80 years left in reserves, according to Edwards. Highway departments from local municipalities are prime users of the aggregate during road construction season.
Other customers include local power companies, which use the aggregate to build access roads for power lines.
“We have one 20-year-old Eriez feeder and another feeder that was installed just recently,” Edwards said.
“The feeders run five days a week, about eight to nine hours per day, both feeding onto the same conveyor belt with the crushed stone. We can crush stone at the rate of 450 tonnes per hour and run the feeders at 270 tonnes per hour. We have the ability to regulate how many tonnes per hour we can run on the belt.”
The benefits of the 75B vibratory feeder include a low profile and compact design, giving employees in the tunnel more room to work, according to Edwards.
{{image2-a:r-w:300}}The heavy-duty 75B feeders work well in the tunnel’s harsh environment because of their electro-permanent magnet drive design. The feeders have no rotating parts such as shafts, cams or bearings, thus eliminating the need for lubrication. The advanced AC feeders can be wired to any AC line and do not require a control to operate.
The 75B series standard units operate at temperatures up to 57oC. High temperature units up to 150oC are available.
Edwards said he re-engaged with Eriez representative agent Tom Brittain, of PennQuip in Muncy, Pennsylvania, when the time was right to purchase the new feeder.
“I’ve been around this business since 1968 and you build confidence in the people you deal with,” he said.
“They know your needs and know the industry. We bought an Eriez feeder from them many years ago and purchased the new feeder based on their direction. They have always treated us right.”
Eriez is recognised as a leading authority in separation technologies. The company’s magnetic lift and separation, metal detection, materials feeding, screening, conveying and controlling equipment has applications in the process, recycling, mining, aggregate and resource recovery industries. Eriez manufactures and markets these products through 12 international facilities on six continents.
The Eriez Australia facility is based in Epping, Victoria.
Source: Eriez Australia