Mining conveyor systems are getting larger, more durable and going underground

First published in February 2020 edition of international Mining

The overall design concepts for surface and underground conveyors are not significantly different. However, underground conveyors require a specific consideration with regards logistics and constructability, together with other considerations such as access and maintainability.  

Considering the limited space underground and naturally dusty environment, even with a high performance dust collection and ventilation system, special attention has to be paid to maintainability of the components, even to change out a complete conveyor belt after 10+ years of operation. 

Another aspect for the conceptual layout of an underground to surface conveyor system is the aim of limiting underground transfer points. This leads to single flight conveyors with maximum feasible lengths and lifts, and thanks to the recent developments in increased belt strength and gearless drive design underground transfer caverns can be minimized and rock excavation costs significantly reduced. ABB Ability™ conveying technology and services support a number of mining businesses. 

ABB, together with Tenova TAKRAF, a leading underground mining project in Chile, provided the underground system (comprising two conveyors of about equal length) as well as the overland conveyor boast advanced gearless drive technology. 

ABB Ability™ solution helped the gearless drives eliminate the need for a gearbox, thereby significantly reducing the number of main wear parts, which results in increased efficiency and reliability, as well as less maintenance being required. Further advantages include a considerable reduction in the drive system’s footprint and the amount of instrumentation required. 

ABB is also working on a new project with GCD for medium power based on PM motor technology. ABB has received an order to replace the shaft mounted geared drives of existing conveyors in a European mine by GCD. The conveyors are connecting the mine with the power station. The gearless drive will be designed so that it can replace the geared drive unit without considerable modification of the existing drive pulley and main structure. It will be 100% exchangeable back and forward compatible. The main motivation to go for gearless was frequent failing motor bearing due to vibration issues and noise limits because of new EU regulations. 

Ulf Richter, ABB’s Global Product Manager, Conveyor Systems, says that digital services for material handling performance and optimization are now available. Due to decreasing ore contents and deeper mines, continuous belt conveyors are becoming more and more important. Even in global supply chains of raw materials, storage locations with belt conveyors and conveying equipment have a great influence on the efficiency of the entire transport process. To date, however, only a fraction of the operating data is used for optimization. ABB has therefore worked with experienced operators to develop a specific KPI system that identifies optimization potential. 

This system is provided as a customized toolbox based on the ABB Ability™ framework with data collection, pre-processing, calculation engine and dashboards. The KPIs are determined with the help of KI methods such as machine and deep learning algorithms to allow new services  such as OEE, energy and load performance; energy efficiency analysis; automated alarm and event analysis including prediction of critical asset conditions; and lifetime estimation and predictive maintenance.