Engineering and Mining Journal - Whether the market is copper, gold, nickel, iron ore, lead/zinc, PGM, diamonds or other commodities, E&MJ takes the lead in projecting trends, following development and reporting on the most efficient operating pr
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EQUIPMENT GALLERY 82 E&MJ; • APRIL 2016 www.e-mj.com DTH Drilling Backhead Solves Excess-water Performance Problems Numa's new Vortex backhead is designed to improve drilling performance and ham- mer/bit life. It is available for Numa's 12- in. hammer line when drilling conditions require a signifi cant amount of water injection. The company explained that, typically, when water is injected into the air supply of a conventional backhead, the water will travel through all hammer components and exhaust out the bottom of the bit to improve hole cleaning. This is not usually a concern, but a drop-off of drilling performance can occur when signifi cant amounts of water are required. The Vortex backhead avoids this by ejecting water out the top of the backhead before it can go through internal hammer components. Numa accomplished this by creating a spinning process, or vortex, in the backhead that leverages the density difference between water and air. Fluids entering the top end of the hammer are spun, pushing water to the outside where it is ejected out the top of the backhead. Air stays to the inside and travels down the feed tube to power the hammer and clean the bottom of the hole. The amount of water ejected by the Vortex backhead can be controlled by two chokes at the top of the backhead. A standard hammer is supplied with 1/8-, 3/16- and 1/4-in. chokes that can be changed to control water injection according to drilling pref- erence and conditions. www.numahammers.com Conveyors for Steep-angle Transport ContiTech has reintroduced to the North American market two conveyor belt products that can carry loads up a ver- tical incline as steep as 90° in surface and underground applications. The belt systems—Pocketlift and Flexowell—are designed to transport bulk materials from loading point to unloading point up steep inclined or vertical applications. Pocketlift systems, for deep-shaft underground applications in the mining and tunneling industry, provide a lifting height up to 800 m (2,620 ft). Pocketlift technology allows the opportunity for a continuous mass fl ow over several hun- dred feet lift height, providing additional benefi ts such as low energy consump- tion, small shaft diameter, low main- tenance costs and no need for under- ground bunkers. Flexowell systems can carry materials over 1,640 ft (500 m) in a vertical lift with capacities up to 6,000 tons per hour (t/h). These systems handle above-ground bulk materials up to 16 in. (400 mm) in fragment size. www.contitech.us Submersible Pump Range Gets New Model Grindex recently unveiled its Maxi H-Lite electrical submersible pump. Equipped with a 25-kW motor, it fi lls a gap between the company's 18-kW Matador and 37- kW Maxi models. The Maxi H-Lite pump is fi tted with a redesigned and optimized top cover, including a new type of ca- ble entry that ensures that the junction chamber remains water-free. The Maxi pump is available with an open impeller, in either hard iron or stainless steel. The hydraulic section features an adjustment sleeve that is standard in the Minex-Mat- ador range, and offers a way to easily re- adjust impeller suction-cover clearance to regain as-new performance after wear. Grindex also has included similar up- dates for the Maxi H, Maxi N and Maxi L in the same product family, and the Maxi H pump received a facelift with a light- er and more compact design. Wear adj- ustment will also be incorporated in the redesign of these 37-kW siblings of the Maxi-Lite, and Maxi H, Maxi N and Maxi L units will be available with semi-open impellers in either hard iron or stainless steel. www.grindex.com