Conveyor bridges used in open-pit mining are gigantic steel structures. To ensure they work precisely and safely, they must be moved with a great deal of tact and are not allowed to go beyond the stipulated end positions. Nowadays, the mechanical cam limit switches used for this purpose fail to comply with the current technical standards and cause a multitude of problems. A retrofit with modern electronic position switches provides conveyor bridges with new precision and significantly reduces maintenance requirements.
Safely controlling mobile system components
Conveyor bridges used in open-pit mining comprise a multitude of mobile components, from the conveyor belt to crawler gears and right through to the swing mechanism and discharge chute. The movement radius of these parts is mainly controlled and limited by using position switches. Older mechanical cam limit switches, however, are often inaccurate and require complex and expensive maintenance. The need to keep an inventory of spare parts also leads to further costs. The modernization of the position switches is an ideal measure to ensure that conveyor bridges can continue to be used – more efficiently, accurately and safely than before.
Retrofitting with electronic position switches by Hübner Giessen
The mobile system components of a conveyor bridge used in open-pit mining were experiencing a variety of problems, including inaccurate position switches, long maintenance and standstill times and a lack of valid safety approval. We improved the system and enabled it to handle the challenging work involved in the heavy-duty field of open-pit mining by replacing its installed mechanical cam limit switches with electronic position switches. The ERC 40 electronic position switch with robust housing was developed for use in extreme ambient conditions. When used by our open-pit mining customer, it not only improved the switching speed. You can find out about the other advantages achieved by reading our case study on “Conveyor bridge / hoist: achieving higher precision and reducing costs and complications by converting from mechanical to electronic position switches”.