Retrofitting pipelines with induction motors

This paper includes a discussion of design considerations, test, and application of a large stiff-shaft two-pole motor designed for fixed or adjustable-frequency drive (AFD) of pumps for a pipeline retrofit. A rotor-dynamics analysis of the rotor bearing system is presented for the as-built design and for alternate bearing designs. Test data is presented for complete shop tests with the motor and drive system. The project consisted of 22 motors plus two spares rated 3000 HP at 1.15 service factor and 3600 r/min at 60 Hz. These motors, rated 4000 V, are for use at variable speeds and torque from 23.5 to 60 Hz. A second, more recent project consisting of 18 motors and one spare rated 3000 HP at 1.15 service factor and 3600 r/min at 60 Hz is also briefly described in the paper. These 4000 V motors are for use at variable speeds and torque from 24 to 66 Hz.