ABB has a large installed base of mine hoists and brake systems in China’s coal mines. For example, it has delivered two hoisting systems to the Majialiang coal mine, a subsidiary of Datong Coal Mine Group. The mine hoisting systems, provided by ABB, are China’s largest and cover the main units, the motors, the control systems, the ACS 6000 MV drives, the break control systems and related technical service. The two systems have a 5.7 m dia., a payload of 45 t and an average payload of 1530 tph. They are now used in the main shaft for the Majialang coal mine, significantly improving operational efficiency. More recently, they have won the order to supply four new mine hoists to the Balasu coal mine project.
ABB’s ACS 6000 MV drives, using two sets of independent systems, including rectifier units and inverter units, control the entire hoist. Under normal conditions, these two systems work separately, and the hoist operates at full load and full speed. However, when one set of systems stops working, the entire hoisting system can be shifted to urgent mode by using the other system independently. Under these conditions, the hoist will operate at a full load but at half speed.
Normally, without adopting ABB’s technology, when experiencing a malfunction, the mine hoist has to stop working for examination and repair, compromising the safety and continuity of mine production.
ABB South Africa has been delivering hoisting systems to the coal mining industry since 1961. In recent years, they have delivered friction hoists to the Sasol coal mines and Anglo Coal mines with payloads of up to 80 t.