On board of our client’s ro-ro cargo vessel where our CBM system is implemented, periodic vibration survey carried out by crew member revealed that the value of vibration velocity RMS for HFO separator exceeds the limit significantly.
Info Marine engineers based on received data and through in-depth analysis issued report. Our diagnosis was clear: HFO Purifier need to be cleaned and checked, bearings of vertical shaft need to be replaced.
According to PMS logs last overhaul of this machinery took place only 3000 Rh ago, but client trusted our expertise and decided to overhaul it again.
It was a very good decision condition of separator after such a short running time is presented below.
1. In gear space found very dirty oil with wear parts
2. Horizontal shaft's worm wheel wear down.
3. Worm with marks of wear.
4. Bowl spindle - found cavitated surface of contact with bowl body.
5. Bowl body - contact surface with bowl spindle also in bad condition.
6. Working surfaces of Bowl body are damaged.
7. Sliding bowl bottom – holes for distributing cone found damaged.
8. Distributing cone found damaged (pins in distributor cone should be installed without clearance, holes in distributing cone are oval now and pins damaged).
9. Distributor found also in bad condition.
10. Bowl hood surface found cavitated.
11. Paring disc upper with marks of cavitation.
12. On removed bearings ware marks of rotation in casing.
Please pay attention that this damage occurred just after 3000 Rh since previous overhaul. The breakdown of purifier was very possible if there wouldn’t be a vibration monitoring.