“Severstal” is one of the world's largest vertically integrated steel and mining companies with assets in Russia, Latvia, Poland, Italy and Liberia. The company employs about 61 thousand people. The company produces hot-rolled and cold-rolled steel products, joist webs and pipes, long products(bars), etc. The main steel mills owned by the company: Cherepovets Metallurgical Combine in Russia (capacity 11.6 million tons per year). The mining segment of the company is represented in Russia by two mining and processing plants (GOK):”Karelskiy Okatysh”, “Olenegorsk Mining and Processing Plant” (JSC “Olkon”), Yakovlevsky Mining and Processing plant annually producing 15 million tons of iron ore concentrate, the coal company “Vorkutaugol” (Komi Republic)
Our cooperation with “Severstal” began in 2006 and for 17 years we have been regularly supplying stator and rotor coils for more than 60 different engines that are used in mining enterprises and the metallurgical industry. In 2019, the company turned to us at SZEMO Holding with an interesting and challenging task in the form of replacing iron and random-wound winding with preformed stator coils of an EVIG 2AO 630J4 electric machine with a capacity of 1450KW.
During the engine repair at the SZEMO holding, the engineering department of REM&Coil proposed to replace the random-wound winding with preformed stator coils. It is no secret that manufacturers of AC electric machines, in order to maximize the automation of production, are increasingly manufacturing AC motors with a capacity of up to 1500 kW using a random-wound winding. During the operation and repair of such machines, a number of difficulties arise:
1. When replacing the winding on high-power electric motors with a length of active iron more than 500 mm, it is not possible to ensure fast and trouble-free wire installation without using equipment that manufacturers have. And the purchase of such equipment for repairmen is unprofitable.
2. The insulation of the random-wound winding wire in 200-400 kW motors with frequency control does not withstand high-frequency voltage loads.
There is the same solution for both problems. Replacement of the random-wound winding with the coil one. In the first case, this makes it possible to install the winding into the stator in a short time, in the second, the winding, made of rectangular wire with insulation made of modern materials, becomes resistant to high-frequency voltage, which increases the stability of the motor to heavy operating conditions.
To complete the task, PO Elektromashina manufactured a new iron and dismantled and fully diagnosed the engine. And the company REM&Coil calculated the new winding, developed a reliable insulation system and manufactured a set of coils for the repair of this electric motor.
"We have been cooperating with REM&Coil for a long time. The main direction is the order of stator and armature coils, commutating field coils to electric motors. The quality of the manufactured coils is at a high level, as high-quality electrical insulation materials are used, both Russian and imported, and some of the best machines for the manufacture of coils. When approving the drawings, all the requests of the client are taken into account. No product comments have been revealed for a long time of cooperation. The company's specialists are competent in technical matters, responsive and professionals in their field!"