Mikheevskiy GOK (Russkaya Mednaya Kompaniya)

Mikheevskoe deposit of porphyry copper is situated in Chelyabinsk region, Vanra district, 20 km to the south from the village of Varna and 20 km to the north-west of the town of Kartaly. This project is a project of federal importance, and in the newest history of Russia this is the most ambitious project of processing and mining combine construction “from the ground up” on CIS territory.

Porphyry copper ores contain cooper, gold and silver. Concentration of metal in ore is very low, that’s why for effective operation significant throughput is required. Exploitable volume of ore in the deposit is about 400 million ton.

Construction of Mikheevskiy GOK started in 2009; start-up of mining and processing combine is planned for the end of 2013. Base engineering is being made by Outotec company (Finland) leading company in this field. Design of the plan was developed by the leading design institute in Russia-“Mekhanobr Engineering” (Saint-Petersburg, Russia).

The largest equipment in Russia manufactured by world leading companies will be set up in the plant: cone gyratory ThyssenKrupp, mills SAG (diameter 11m), ball mills (diameter 8 m), Flotation machine Outotec (volume of box 300m3).

Low concentrations of cooper in ore, heavy climatic conditions are the reason to search and imply new technologies. Trunk conveyor by JSC “Tyazhmash”( Syzran)of 1415 m. length and 1600 m width to transport ore from the deposit to the ore-dressing plant will be used.

Scheme of power-drive and take-up stations of conveyor

In this conveyor the scheme with two driven balls are implied: the first with two electric motors, the second-with one electric motor but on the free side it has a reserve motor. To access of this electric motor coupling should be set in-between electric motor and reducer gear.

JSC “NPP TechnoProekt” offered modern solution with the following equipment:

- wound electric motor Suf560HV6 by EMIT S.A., Poland

- soft start system model УПТФ-1000M-3 pcs by JSC “Enegrocomplekt”(Saint-Petersburg) to provide not only simultaneous start but synchronization of drives in torque.

EMIT S.A.( Poland) has 90-year history and since that time the company has earned reputation of reliable manufacturer who can solve difficult technical tasks.

Electric motor Suf560HV6

The selection of electric motor was based due to its high operational characteristics wide field of implementation as part of conveyor drives and high reliability. Electric motors were designed especially for heavy start conditions including conveyors, they have high degree of protection IP54 and can be used both indoors dust area and outdoors.

Special characteristic of these electric motors is their ability to provide besides nominal duty with high efficiency also service speed duty for service activity and examination of conveyor belt. In service duty 20% of motor nom speed (200rpm) 15% of nom torque is provided that allows to run conveyor even with rests of ore on. Start-up of wound electric motors would have been impossible without special starters which provide not only simultaneous start of driven motors (3 pcs) but synchronization of drives in torque. JSC “NPP TechnoProekt” in cooperation with JSC “Energocomplekt” designed starters to synchronize wound electric motors of the drive of trunk conveyor.

Soft starter (control box closed/open, resistor block)

Besides nom duty soft start system provides service duty with synchronization in torque and has the possibility of regulation of start time with changing of control thyristor angle. There are 3 main starters in the system and the fourth integrated into this system with ability to replace any of the three. Thus hot reserve is provided. System doesn’t perturb the feeding net and provides reliable start-up of electric motors meeting all necessary start characteristics.

JSC “NPP TechnoProekt” successfully made some technical solutions:

- conveyor start-up system was designed to provide synchronization drives in torque both in nominal duty and in service duty;

- service speed duty provided with usage of electric motors with special ventilation system which allowed the Customer to save costs;

- hot reserve capacity of electric part of conveyor drive provided( additional electric motor and additional starter integrated into the system).

Witness tests were successfully held, and the equipment was delivered to construction site of JSC “Tyazhmash”-conveyor set-maker on time due to the signed Contract. JSC “NPP TechnoProekt “will make commissioning and start-up of supplied equipment.