Hello,
I'm currently troubleshooting a new horizontal induction motor (API 541), 750 HP, 3583 RPM (59.7 Hz), 4000 V, 75.3 A, showing high 3x seismic vibrations axially at 3.5 mm/s 0-p during shop solo run test. What in your technical opinion could be the reason behind this given that shaft relative vibrations are lower than 1 mil pp and there is no thrust bearing installed on this machine? For your information, radial seismic vibrations are lower than 1.5 mm/s 0-p, no high temperatures detected on the sleeve bearings during the test. Worth mentioning that all radial/axial seismic vibration readings are below 1 mm/s 0-p at the beginning of the test. Soft foot was checked in the testing facility and the highest recorded is 0.03 mm against API 541 requirement, which is 0.025 mm. Moreover, impact test was performed axially showing 120 Hz.
I'm currently troubleshooting a new horizontal induction motor (API 541), 750 HP, 3583 RPM (59.7 Hz), 4000 V, 75.3 A, showing high 3x seismic vibrations axially at 3.5 mm/s 0-p during shop solo run test. What in your technical opinion could be the reason behind this given that shaft relative vibrations are lower than 1 mil pp and there is no thrust bearing installed on this machine? For your information, radial seismic vibrations are lower than 1.5 mm/s 0-p, no high temperatures detected on the sleeve bearings during the test. Worth mentioning that all radial/axial seismic vibration readings are below 1 mm/s 0-p at the beginning of the test. Soft foot was checked in the testing facility and the highest recorded is 0.03 mm against API 541 requirement, which is 0.025 mm. Moreover, impact test was performed axially showing 120 Hz.
