Modern Mining April 2016

PRODUCT News

for an underground trunk belt conveyor which is driven by three 400 kW WEG 1 000 V motors. The conveyor belt has been designed to transport 4 800 t/h. The complete E-House including the base, cladding (side walls and roof ) and all internal electrical equipment was designed and manufactured by Shaw Controls at its modern comprehensively equipped facility in Johannesburg. Kirsten Larkan, Zest WEG Group Africa, tel (+27 11) 723-6000 Shaw Controls customises E-House for Zibulo

Custom built E-Houses are said to offer a rapid and far more cost effective alternative to the building of brick and mortar substations, and this is especially true in an underground appli- cation. This is one of the reasons why Zibulo Colliery contracted Shaw Controls, a division of Zest WEG Manufacturing, to design and manufacture an E-House for its operation in the Mpumalanga coalfields. Containerised electrical control installa- tions in underground applications are not new. Bevan Richards, COO of Shaw Controls, says the concept was first used during the sinking of many of South Africa’s gold mining vertical shafts when ISO marine containers were equipped with mimic panels and other ancillary equipment. “However, the evolution and development of pre-manufactured electrical substations or E-Houses has opened up numerous pos- sibilities including the ability to completely customise the unit according to process and plant requirements,” Richards explains. Specifically designed for this underground application in a coal mine, the E-House was designed with several specific parameters taking precedence. Underground height restrictions meant that the structure itself had to be lower than usual but would still need to accommodate all necessary electrical infra- structure and allow for sufficient headroom for cooling. Richards says it is testimony to Shaw Controls’ mechanical design capability that its engineers were able to design such a low profile steel structure that could house all the equipment and still maintain the requisite internal clearances. He says that extensive use was made of Solid Works CAD software during the design process and this ensured the integrity of the design. The final E-House dimensions are a height of 2,3 m, a length of 8,5 m and a width of 3,5 m. Another important criterion that had to be met was the voltage being used on the mine. The majority of mines use 525 V but at Zibulo Colliery the voltage being used is 1 000 V. This required special design work on both the Motor Control Centre (MCC) and the Variable Speed Drive (VSD) to ensure safe operation at this voltage. Operation in a coal mining application brings with it additional specifications and these were met by equipping the E-House with a fire detection and suppression system. The E-House is the prime power centre

Designed by Shaw Controls for underground applica- tion in a coal mine, the E-House was designed with several specific parameters taking precedence.

April 2016  MODERN MINING  51