New modern drives on the conveyor of the Kovdorsky Mining and Processing Plant

Kovdorsky GOK (Kovdor mining and processing plant) is a large enterprise in the city of Kovdor, Murmansk region. Kovdorsky GOK is the second largest producer of apatite concentrate (raw material for the production of phosphate fertilizers) in Russia and the only producer of baddeleyite concentrate in the world, a large producer of iron ore concentrate.

The official opening of the Kovdorsky GOK took place on September 5, 1962.
Since 2001, the Kovdor Mining and Processing Plant has been part of the EuroChem Mineral and Chemical Company, which is the largest producer of mineral fertilizers.

Volume of output of the plant's main products:
• iron ore - 5.70 million tons per year;
• apatite - 2.70 million tons per year;
• baddeleyite - 8.85 thousand tons per year.

The EuroChem company strategy is aimed at the long-term sustainable development of KGOK OJSC:
• increasing our own raw material base
• increasing production capacity
• increased productivity
and is provided through investments.

The next investment project “Modernization of electrical equipment” of the EuroChem company, which Kovdorsky GOK has begun to implement, is aimed at increasing the productivity of the equipment operating at the plant.
As part of this project, the drives of the main conveyor LTMP-160-5000-2 of the DKK section of the Crushing Plant must be replaced: 5 electric motors with a wound rotor AKNZ-2-15-57-8U3 (800 kW, 6 kV, 750 rpm).

The main conveyor is designed for dispensing large-sized rocks and ores from deep quarries using a cyclic flow technology for their extraction.

During the analysis of the current situation, the following basic equipment requirements were identified:
• electric motor weight limit;
• preservation of the existing foundation;
• reducing the time spent on installation and commissioning of electric motors;
• modern and reliable equipment that ensures reliable operation and ease of maintenance.

TorMashEnergo CJSC, being an official partner of EVIG Elektromotor Energy Kft, Hungary, Budapest, together with technical services, proposed a technical solution based on a modern asynchronous electric motor with a phase rotor 3ANS500N8.

To increase operational reliability (electric motors are designed to drive mechanisms with severe starting conditions) and ease of maintenance, the following was proposed:
• The casing of the slip ring service unit is dismountable in a horizontal plane along the axis of rotation, and in the upper part of the casing there are 2 inspection windows, allowing maximum inspection of the brush apparatus.
• Increased dimensions of the terminal box.
• The stator winding is heated in a non-working state.

 Technical parameters of the 3ANS500N8 electric motor:
• Power: 800 kW 
• Voltage: 6000 V
• Rotation speed: 741 rpm
• Mounting version: IМ1101
• Weight: 5250kg
• Degree of protection: IP54
• Cooling method: ICA37
• Insulation class: F
• Cosφ=0,85
• Stator current: 95.3 A,
• Rotor current: 590 A

Scope of application of 3ANS500N8 electric motors:
Energy, oil production, oil refining, mining, metallurgical industries and other sectors of the national economy.

The delivery of electric motors was carried out by ZAO EnergoFront ahead of schedule.

Acceptance of electric motors was carried out in several stages, including with the participation of customer representatives during acceptance tests of the manufacturer.

At the moment, CJSC EnergoFront is organizing installation and commissioning work at the site.

This delivery completed the full cycle of replacing exhausted AKNZ-2-15-57-8U3 electric motors with 3ANS500N8 electric motors.