Large vertical asynchronous motors up to 25,000 hp

Description

Large vertical motors are designed to drive high-power vertical pumps: power-station circulating pumps, intake and water-main pumps, irrigation and drainage stations, and cooling-water pumps. They are produced in powers up to 25,000 hp and use many proven solutions of the World Series™ range: the Thermalastic® insulation system, a rotor with copper bars and a rigid welded frame. The main task of a vertical motor is to take up the axial load from the pump impeller and the weight of the rotating parts. For this, several types of thrust bearings are offered: deep groove ball bearings, angular contact bearings, spherical roller bearings, sleeve bearings and KTB-type thrust bearings. The bearing type is selected according to the magnitude and direction of the axial force, the rotational speed and the maintenance requirements. Stator windings use the proprietary Thermalastic® insulation system: mica insulation of the form-wound coils, vacuum-pressure impregnation of the wound and connected stator with solvent-free epoxy resin, and oven curing; the cycle is repeated to eliminate voids that cause corona. The insulation withstands long-term voltage stress, moisture, contamination, thermal cycling and chemical effects. In addition to custom machines, the company produces standard medium-voltage vertical motors with hollow and solid shafts (WPI and TEFC, 200–1000 hp, 2300/4000 V) for pumps. Large machines are manufactured and tested at the plant in Round Rock, Texas, USA, which has produced large DC motors since 1976, AC induction motors since 1977 and synchronous motors since 1978.

Technical specifications