Türkçe (Turkish)
English (İngilizce)
Problem Identification:
- The newly installed Motor – Gearbox – Pump equipment at a petrochemical plant tripped during the initial start-up test phase due to high temperatures.
- Analysis of data from vibration and temperature sensors revealed an abnormal condition in the gearbox output bearing.
When examining the trend values of the temperature sensor located in the reducer output bearing, it is observed that the equipment exhibits a normal heating trend up to 75 degrees Celsius, but subsequently the temperature value rapidly rises to 105 degrees Celsius, causing the equipment to trip.
- When examining the ‘shaft centre line (SCL)’ graph obtained from the two X & Y displacement sensors located on the bed, it was observed that the rotor exhibited a significant change in position during the acceleration and heating phase. Following this position change, which is approximately ~150 microns Pk-Pk, it is seen that the position orientation instantly changes to the right-upwards and continues to change in this direction until it trips from the temperature value.
- This behaviour observed in the temperature and shaft centre graph indicates a ‘Rotor Rubbing’ problem. It is estimated that the rubbing problem caused by the rotor contacting the inner surface of the bearing stems from a misalignment/assembly issue.
Result:
- After dismantling the gearbox, a friction problem was observed on the bed.
- Following improvements to the alignment and assembly processes, the equipment was successfully commissioned.
