Engineering & Mining Journal

JUN 2013

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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Page 106 of 171

BAUMA 2013 In 1988, LKAB was one of the founders of G-Drill. It would continue to drive the development of the waterpowered drilling technology. The aim was also to find other industries where the water-powered drilling technology would make the same benefit as it did for LKAB. In 2002, the subsidiary changed its name to Wassara and in 2012, it upgraded to LKAB Wassara. The goals are still the same. In recent years, Wassara has been building an organization designated to handle the market demand from new areas such as ground engineering, dams and exploration drilling. "We now have the technology, resources and references to achieve success," said Kent Boström, communications manager at Wassara. "We can now show several examples of demanding applications where the water-powered drilling has been absolutely superior to other drilling technologies." The heart of the system is its worldwide patented Wassara DTH Hammer, using water for power transmission. The drilling technology is suitable for most applications, particularly in applications that are difficult or unsuitable to drill in with other drilling technologies. Using water is optimal because it cannot be compressed. The amount of water leaving the hammer is the same as has been fed to the system. The minimal pressure loss means that the power is unchanged no matter how far one is drilling. This means that the drilling efficiency is equally high regardless of whether the bore is 10, 100 or 1,000 m. Using water for power transmission also means that the power fully reaches the hammer, enabling drilling in smaller borehole dimensions. Today, the waterpowered drilling technology can be used for drilling holes with diameters from 65 to 254 mm. The water pressure is up to 180 bar, compared to 30 for air. The difference is noticeable on the stroke rate. A Wassara hammer gives 3,600 blows per minute (60 Hz), while an air-powered hammer gives 2,000-2,700 blows per minute (35-45 Hz). The precision was also important for LKAB when the technology was developed. Several tests indicate that the deviation of a borehole is around 1%-2% in a 200-m borehole, to be compared with deviation of about 15%-20% when drilled with air-powered technology. Power consumption is reduced significantly: • To power a 6-in., air-powered DTH hammer, a compressor that gives 570 l/s at 35 bar is required; the required power is 430 kW. • To power a 6-in., water-powered DTH hammer, a high-pressure pump that gives 490 l/min at 200 bar is required; the required power is 190 kW. LiuGong Expanding into Large Size Machines Go big or go home. This is a popular phrase LiuGong Machinery Corp., Asia's leading full-line equipment manufacturer, takes seriously. In the past four years, the company has quietly expanded its ability to produce large-sized construction equipment machinery. Through smart acquisitions, redirection of some of JUNE 2013 • E&MJ 105

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