Success Stories

Motor Speed Change and Shaft Torsional Data

1250 HP, 8 Pole, 4160 Volt, WP-II Induction Motor (Converted from 1500 HP, 6P)

A client approached designmotors requiring both a speed change and shaft torsional datasheet on a motor previously in service on another application. This motor was to be used on a reciprocating compressor application at a different speed than it was originally designed for and the end user required the torsional datasheet to analyze their drive train for any torsional resonance. For the electrical redesign, our client provided the original stator and rotor information, which we used to confirm the legacy rating and produce the new design. For production of the torsional datasheet, we were given both dimensional and material data on the shaft and rotor assembly. With this data we produced a complete 3D model of the rotor assembly, calculated the torsional stiffness of the shaft, and ultimately created the required torsional datasheet. Upon receipt of the needed data, we were able to complete this project in less than three days. When you need motor data that you can’t wait for others to complete, get in touch with designmotors and see how we can serve you.

Motor Performance Calculated for Legacy Motor

400 HP, 16 Pole, 480 Volt, ODP

Designmotors was approached by a regional motor service provider for speed versus torque and speed versus current curves for a legacy motor, which the end user had no nameplate or other data on. This is data that would have been available decades ago when the motor was originally produced but was reportedly no longer available through the motor’s original manufacturer. Our client supplied their standard stator and rotor datasheets, which we used to run the existing electrical design and determine the motor’s performance at full load and during acceleration. The data we provided gave the end user valuable operating characteristics for their motor which they could use for reasons ranging from new controls settings to procurement of replacement machines. In cases where a motor OEM isn’t able or willing to provide the design data you need on your machine, get in contact with designmotors.

Custom New Motor Two Speed Design

200/100 HP, 10/20 Pole, 460 Volt, Force Ventilated, Two Speed / One Winding, NEMA Design D Induction Motor

Designmotors was contracted by a client to produce a custom new motor design that they were not able to otherwise produce internally. Utilizing their standard stator outer diameter and adhering to the room for overall coil length given by the manufacturer, we produced a new motor design that both met the end user’s performance requirements and fit into our client’s standard mechanical package. Upon design completion, we provided our client with new stator and rotor lamination manufacturing drawings as well as the calculated performance data they could provide the end user. This project highlights designmotors’ capability to serve as an external engineering resource whenever your internal engineering department either lacks the design expertise or time needed to meet your customers’ needs. Whether you need us to design one motor or aid in product development for mass manufacture, we have the experience and resources to meet your customers’ needs.

Diagnosis of a Noisy Motor

350 HP, 8 Pole, 2300 Volt, TEFC Induction Motor

Designmotors was contacted by a service provider whose customer reported a motor previously redesigned for a new speed, producing noise the end user wanted diagnosed. Although the original redesign was not carried out by designmotors, through communication with the motor’s original manufacturer and the repair provider who carried out the speed change, we were able to successfully gather needed data and pinpoint the source of the audible noise. Because of the magnetic pole count change in the redesign, a resonant condition was produced in the stator core. A fourth pole pair excitation frequency was found to be within a range deemed too close to the stator core’s calculated natural frequency, which produced the reported electromagnetic noise. Our client was able to couple this diagnosis with their own vibration analysis of the motor to recommend a path forward for the end user. When you have problem with motors that puzzle your team, get in touch with designmotors.