English (İngilizce)
Türkçe (Turkish)
Problem Identification:
- Due to a vibration problem experienced in the CID fan motor located in a power plant, support was requested from the Resonance Institute technical team.
- A constantly changing vibration pattern is observed in both bearings of the motor.
- While this symptom is not observed in measurements taken with an accelerometer on the bed, the shaft sensors, which are also transferred to the DCS system, clearly show the variable vibration characteristics.
- For diagnosis of the problem, continuous measurements were taken over five days using multi-channel analysers via the DCS.
Diagnosis:
- When long-term measurements were evaluated, it was determined that the amplitude and phase of 1X (rotation frequency) continuously changed.
- In some cases, vibration levels have been observed to approach the B/C limits according to the ISO 7919-2 standard.
- 1X genlik ve fazının yaklaşık olarak 4-5 saat periyoduyla bir tam tur attığı tespit edilmiştir.
- Literatür çalışması yapılmış ve durumun sızdırmazlık elemanlarında görülen “Yumuşak sürtme” (Newkirk Etkisi) olayından kaynaklandığı düşünülmüştür.
- Sızdırmazlık elemanlarının kontrol edilmesi önerilmiştir.
Result:
- An inspection was carried out on the CID fan motor under the leadership of Veli Can Yeşil, Technical Service Manager at the Siemens Adana motor maintenance workshop.
- As expected, carbonisation of the oil in the sealing elements has been observed.
- To prevent this situation from recurring, it has been decided to place V-rings in front of the sealing elements and to increase the gaps between the sealing elements.
