ABB has used its global expertise in automation solutions for open pit mining and material handling to provide a unique, custom-built automation system for a bucket wheel excavator (BWE) for Neyveli Lignite Corporation Limited, in Tamil Nadu.ABB Cottbus, Germany is the MTC (Main Technology Center) for open pit mining. ABB Cottbus supported for this bucket wheel excavator project, by providing the Continuous Mining Motion Control program, which is used in the Variable Frequency drives. Also ABB Cottbus has deputed their experts for commissioning of the various drives.
ABB introduced a variable frequency drive (VFD) ACS 8004Q for the bucket wheel application, which significantly reduced the wear and tear of buckets and optimizes energy consumption in the operation of the machine. The indigenously developed solution was implemented in record time and helped boost the performance of the bucket wheel. Bucket-wheel excavators are pieces of heavy equipment used in open pit/ surface mining, especially for lignite. It is a continuous excavation machine capable of removing up to 3430 cubic meters of soil / strata per hour.
The excavation component itself is a large rotating wheel mounted on a boom. On the outer edge of the wheel are a series of buckets. As the wheel turns, the buckets remove soil or strata from the target area and carry it around to the rear of the wheel, where it falls onto a conveyor, which carries it up the arm toward the main body of the excavator.
Discharge conveyor carries it further and discharges it on the overland conveyor. The most favourable soil and strata conditions for BWE operation are soft, unconsolidated overburden materials without large boulders.
ABB partnered with ThyssenKrupp Industries India Limited, the original equipment manufacturer (OEM) for the project, to develop the unique automation solution. ABB’s scope included composite solutions spanning engineering, manufacturing, supply, erection supervision, testing and commissioning of machine electrics, drives, motors, automation system and field instruments.
Electrics comprised HT switchboard, transformer, motor control centers (MCC) and cables for the complete machine.
The automation system included AC800M controller, S800 IO’s and process panel. Communication with the remote IO’s, process panels and field devices is through Profibus network.
The solution was designed after detailed studies, analysis and simulations. The objective of the application software designed to operate the system was to ensure even loading of the conveyor belt, minimize idle operation and form stable slopes. ABB’s application engineering team developed the application programme including the automation of the entire process of soil excavation. This software seamlessly directs the bucket wheel to follow the optimal track, thereby helping the operator to enhance its productivity.
For more information: www.abb.com/mining
Key benefits
- reduced wear and tear of the buckets
- energy saving
- avoidance of overload trippings
- optimum use of the BWE
- increase in machine availability time