IM 2019 November 19 | Page 27

HIGH PROFILE shovels are now equipped with AC rather than DC drives as they offer better performance/higher eficiency and a lower failure rate. The power factor for an AC drive is 0.96% relative to DC at 0.9%. The company works with both ABB and Siemens with the choice down to the customer, which is sometimes related to whether there is a local service centre in the country where the mine is located. All the programming of the drives is done by TYHI in- house. Another new technology addition is an anti- impact system that prevents the dipper door impacting with the boom or the crawler track shoes during operation. The system monitors the dipper position in real time and compares it with the shovel swing movements. A payload monitoring system is also offered that analyses the forces being applied to the dipper with additional sensors as a second check. TYHI shovels also have a tooth monitoring system which is camera-based but can distinguish between teeth and rock material. one year warranty is typical during which period TYHI addresses operational issues free of charge including any new parts that are needed. IM asked TYHI why mining customers like its WK shovels and why it has been the most successful Chinese mining equipment OEM to date outside of China: “The motors we use are very reliable, and don’t need much maintenance for almost 25,000 hours. This motor was designed in-house by us but manufactured by our partner in China. We have proven that these motors require less servicing than those on competitor shovels. We have also been told that the WK machines have a lower initial A key export milestone was the delivery of a WK-55 shovel to Anglo American’s Mogalakwena platinum operation cost as well as a lower service and maintenance cost, despite having the same or better performance.” Reliability, high transmission efficiency and low power consumption are also emphasised. In design terms, the shovels use gear rack crowding for powerful penetration of the muckpile and high efficiency. The transmission gears are carburised to increase surface hardness and lifetime. The propel mechanism uses planetary reducers and a higher position drive to improve cycle life. Air release spring set disc brakes are used. The company has also made an effort to adapt its machine to mining conditions. For the mentioned Julong Copper Finally, a parts and consumables health monitoring system looks at critical parts to allow decisions on whether they can keep working with only a minor service to further increase shovel availability. Overall, the company offers a review with mining customers every six months or every year to assess the shovel and make up to date service recommendations, especially taking current working conditions into account. Machine condition monitoring means TYHI can also produce daily, weekly and monthly machine condition reports with recommendations. In production terms, TYHI guarantees from 25,000 to 30,000 hours until first major service depending on the working conditions. Following delivery, TYHI sends a team of 20 service engineers and technicians to work with the customer during the assembly and commissioning period, with the customer providing ancillary lifting, special tools, nitrogen etc. Following the machine commissioning, TYHI staff provide operator training for a period of two weeks. TYHI staff as well as customers can also train on TYHI’s shovel simulator at the factory, supplied by China’s SIEI. In terms of the ongoing maintenance and service of the shovels, sometimes mines have their own team and sometimes they use contractors. A Russia is the largest export market to date, with 24 large shovels and counting and customers including Polyus Gold (one of whose machines is pictured), KRU and Metalloinvest Qulong and Zhibula copper mines in Chinese Tibet, which are at over 5,300 m altitude, TYHI supplied pressurised cabs on shovels for easier breathing conditions for operators. These high altitude machines also have an anti-lightning system. For cold climates, such as machines in Russia working down to temperatures of -60°C there are special mechanical adaptations, such as use of different steel grades, isolation systems and heaters for lubrication feeds. IM Drill More with RockMore Visit us Boo at STU V th # D15 A 6 Bits Rods Couplings Shanks DTH Mining Construction Quarrying Tunneling Water-well ® R o c k M o r e ® International Rock Drilling Tools Wilsonville, Oregon USA Tel +1 (503) 682-1001 [email protected] Judenburg, Austria Tel +43 3572-86300 [email protected] NOVEMBER 2019 | International Mining 25