Large electric machines

Production of large direct current machines

• direct current electric motors

Direct current electric motors of П2 series and 4П series are intended for drives of rolling mills, drilling rigs, snow plows, excavators, crane equipment, drives in machine tool industry and other industries. Electric motors manufactured by “UKRENERGYMACHINES” JSC meet requirements of GOST 183-74.

• direct current generators

Direct current generators are manufactured on the basis of direct current electric motors of П, П2, 4П series and serve to power electric motors using generator-motor system, power excitation windings of large turbogenerators, and are used as high-amperage welding generators.

In 50s of XX century, plant began to produce large direct current electric machines for metallurgical, coal and chemical industries. Among delivered products there are motors of the largest rolling machines with production of rolled products from 3 to 6 million tons per year.

During design of direct current electric machines, specialists of “UKRENERGYMACHINES” JSC use automated design system (CAD).

Large direct current ACCM electric machines (hereinafter electric motors) of 18-26 dimensions with capacity of 315 to 10 000 kW in one armature are designed to drive various types of mechanisms that require speed regulation within wide limits and in conditions of frequent overloads. Rolling mills of the largest metallurgical plants of Ukraine, Kazakhstan and other foreign countries are equipped with these electric motors.

Large DC electric machines of large and extreme power are functionally divided into two large subgroups:

• The first group of motors is intended for electric drives of rolling mills: slabbing, blooming, thick-sheet, thin-sheet, tube, grade rolling mills with high degree of regulation, which provide intensive reversal with high current loads. Motors for heavy, powerful thick-sheet mills, such as “3600”, “3000” can withstand constant-acting, sign-changing axial loads transmitted by mills up to 500 tons. These motors can withstand enormous torsional fluctuations in shaft line, caused by capture of rolling speed, two-ingot rolling, presence of increased clearances in spindle connections.

• The second group of motors is intended for electric drives of mine hoisting machines, operating conditions of these motors are less stressful than in rolling motors.

All rolling motors are produced on slide bearings with centralized oil supply through emergency sumps mounted on bearing cap. Its capacity is such that it ensures normal operation of sliding supports when oil supply is stopped and there is no electrical braking. Forced ventilation in closed cycle. Motors for mine lifting machines are made on rolling bearings, without centralized oil supply, forced ventilation in open cycle.