Aggregates Manager Digital Magazine
Issue link: http://read.dmtmag.com/i/387031
EQUIPMENT MANAGEMENT 13 AGGREGATES MANAGER October 2014 A pump that sizes up Electric submersible pumps are the most commonly used pumps for dewatering aggregate mines. ey are small and lightweight, and when it comes to maintaining the pumps, choosing the right one for the application is one of the biggest decisions you'll make. Using a pump that isn't sized for the application can lead to issues down the road, such as a broken sha, dislodged seal, or thrown impeller. In aggregate mines where dewatering is oen critical to production, that means costly downtime. To avoid this, there are three things to consider: the material you are pumping, how far you need to pump it, and the elevation to which it will be pumped. If it will be moving water and ag- gregates rather than just water, you'll need a model that is rated for that application and is equipped with impellers made of a durable material, such as cast iron. Other materials, like polyurethane, can handle water, but the abrasive materials such as aggregates can cause them to wear out quickly. Electric submersible pumps rated for these applications can typically move aggregates as large as 1 inch in diameter with minimal wear to components. From there, you will want to confirm the pump can move water as far as you need it to go. Generally, the farther the pump is from the water site, the greater the gallons per minute (gpm) it will need to move the water to or from that location. And if the water has to move uphill, the pump also will need more head capac- ity; in other words, how high the pump can raise water. Electric submersible pumps operate with as much as 5,300 gpm and can pump water as high as 275 feet. Outputs can be as wide as 10 inches in diameter for even greater flow capacities. Get immersed in the details Once you've determined the right size, make sure the pump is built with durable materials and has features that will withstand long run times and the harsh conditions of aggregate applica- tions. e pump's wear plates and seals play an important role in that, since they help protect the internal components. Choose pumps with double mechanical seals, which provide a consistent, watertight interface. Some manufacturers offer stainless steel seals, which last longer than rubber seals and are more durable, making them a good fit for aggregate applications. Also look for mechanisms that stop the unit if it overheats or the electric current overloads the pump. On most models, the pump will automati- cally restart aer it has cooled. is helps protect the motor from damage and extends the life of the pump. To select the correct pump, consider the material being pumped, the distance it is being pumped, and the elevation to which it is being pumped.