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REBUILDS 26 E&MJ; • JANUARY 2017 www.e-mj.com Flanders: Upgrading Drills for Higher Productivity U.S.-based Flanders claims to repair more dragline motors than any other company worldwide, as well as having 65 years of experience in electric shovel motor re- pairs. It also offers its Freedom open-ar- chitecture platform, which, it said, brings new life to existing equipment by replac- ing proprietary OEM control components. Mid-last year, the company celebrated the 10 th anniversary of its Freedom sys- tem for drills, Ardvarc (Advanced Rotary Drill Vector Automated Radio Control), a drill-control system that offers various lev- els of autonomy. In its most basic form, it delivers better data on blasthole posi- tioning, drilling conditions and machine operation, resulting in improved fragmen- tation. While at its most advanced level, it is a fully autonomous drilling solution, providing productivity gains up to 30%, Flanders stated. Ardvarc was developed from a request from a surface mining customer who had problems with its electric drill motors. Flanders ascertained that the shortened motor life was due to the improper control of the motor drive system, and offered a solution that provided the customer with a 20% increase in productivity. The company provided E&MJ; with details of an Ardvarc installation project that it recently undertook for a South Af- rican iron-ore producer. The mine has a fleet of six Cat 6420C blasthole drill rigs to produce 44.9 million metric tons per year (mt/y) of haematite ore, at a strip- ping ratio of 3.5:1. Automation of the drill fleet began in June 2015 with the installation of a One Touch-style system on one drill to test the efficacy of the technology. As the name suggests, One Touch drill control just re- quires the operator to press one button for the system to undertake the entire rig po- sitioning, setting up and drilling process. The entire fleet was equipped by November 2015, with the mine hoping to achieve ful- ly autonomous drilling by the end of 2016. By the end of the study period, 85% of holes were drilled using One Touch, Flan- ders reported. The mechanical availabil- ity of the drills rose from 85% to 90%, while the drilling accuracy increased from an average of 30% holes drilled on plan to a little more than 90% after One Touch automation. Drill cycle penetration rates improved by 27%, while the drill fleet productivity improved by more than 50%. New 'Brains' From ABB As Boris Rathmann, ABB Automation's product manager for shovels and drag- lines, pointed out to E&MJ;, while rope shovels are mechanically robust and can have a 30-year life, after a certain period of operation, upgrading their electrical equipment will improve reliability and re- duce maintenance costs. Rathmann added that the capital cost of the entire electrical equipment is about 10%-12% of a new rope shovel, meaning that a retrofit of an existing shovel can be an efficient way of extending its life for another 10-15 years. Usually, just five to six weeks are needed to replace the elec- trics, including commissioning, he said. With AC technology offering a robust motor and reliable power electronics with digital drive control, in 2012, ABB worked with Joy Global MinePro Services on an AC upgrade for one of Drummond Coal's BE395B mining shovels. The machine had been built in 1987, with Drummond con- vinced that a retrofit can be a cost-efficient alternative to a new shovel, ABB noted. In addition to AC technology applica- tions, ABB has equipped two smaller rope shovels with modern DCS800 DC con- verters with reactive power compensation systems at a quarry in Germany. The new fully digital converter and drive control have helped to improve reliability and cut maintenance costs, with a 25% reduction in DC load surge currents and measured energy savings of about 15%. As well as providing conversions like this, ABB offers turnkey overhaul services for the engineering, delivery, assembly and commissioning of electrical equip- ment for mining excavators of all types. An example is for a SRs 2000 bucket-wheel excavator in Germany, where the compa- ny's scope of work includes medium- and low-voltage switchgear, transformers and low-voltage AC drives. In addition, ABB is supplying the control system with semiau- tomated and fully automated functionality for a belt-loading transfer point. Another recently German coal industry project has involved upgrading a large SRs 6300 BWE with a new 12-megawatt (MW) AC drive system for all of the machine's main functions, including the bucket wheel, hoist, swing, crawler tracks and conveyor belts. ABB has provided elec- trical services for this 14,000-cubic-me- ter-per-hour (cmph) machine since it was commissioned in 1981, demonstrating, as Rathmann explained, what lifecycle ser- vice can mean for large mining equipment. Liebherr Offers Parts Remanufacturing Liebherr stated that its remanufacturing (reman) program enables customers to significantly reduce the total lifecycle cost of their mining equipment without com- promising quality, performance and reli- ability. Another benefit is the way in which equipment operators can contribute to environmental sustainability through sub- stantial material and energy savings. The company pointed out that major components account for up to 80% of customers' mining equipment mainte- Data from blasthole drills show marked improvements in both meters and tonnage drilled after being upgraded with Flanders' Ardvarc system.