COMMISSION REPORT, HPP GROUP “RODOPI”, NEK EAD
Hydro unit KhG-3 and lathe: cooler bearings, quieter gearing — no teardown
Hydraulic unit bearings cooled down, machine gear noise decreased, run-in improved. 10–13 °C — hydro unit bearing temperature after 18 h of operation, 47–51 → 37–38 °C; 4 dB — lathe gearbox noise after three months, 75 → 71 dB (2003).
HPP Group “Rodopi”, NEK EAD
Key results
| OBJECT | AGE AND SPECIFICATIONS | WHAT WAS MEASURED |
|---|---|---|
| Hydro unit KhG-3, HPP “Beli Izvor” | Turbine NTA 176/44×14, built 1952; generator 745 kW, 6300 V, 428 rpm | Temperature and vibration of bearings No. 1 and No. 2 |
| Lathe S 8 M, RMC Plovdiv | built 1970, in normal service at the repair and machine shop | Gearbox noise level |
Hydro unit KhG-3 — bearing temperature
| BEARING | BEFORE TREATMENT | AFTER 18 H | FOURTH DAY |
|---|---|---|---|
| Bearing No. 1 (generator side) | 47 °C | 37 °C | 43 °C |
| Bearing No. 2 (flywheel side) | 51 °C | 38 °C | 45 °C |
Readings taken with the unit running, two or three times a day; over the whole observation period no reading exceeded the initial level.
Hydro unit KhG-3 — bearing vibration 24 hours after treatment
| MEASURING POINT | AMPLITUDE, µm | VIBRATION VELOCITY, mm/s |
|---|---|---|
| Bearing No. 1, X axis | 8 → 7 | 0.1 → 0.1 |
| Bearing No. 1, Y axis | 7 → 6 | 0.1 → 0.1 |
| Bearing No. 1, Z axis | 4 → 3 | — |
| Bearing No. 2, X axis | 7 → 6 | 0.12 → 0.1 |
| Bearing No. 2, Y axis | 6 → 5 | 0.11 → 0.1 |
| Bearing No. 2, Z axis | 3 → 2 | — |
Measured with a “SCHENK” vibrometer; “before” and “after” were taken at the same unit load of 0.5 MW.
Lathe S 8 M — gearbox noise
| MEASUREMENT | GEARBOX NOISE LEVEL |
|---|---|
| Before treatment, 28.03.2003 | 75 dB |
| After three months of operation | 71 dB |
The compound was added in three stages, 8 hours of machine operation apart; the gearbox was not disassembled.
Commission conclusion
Current equivalent
- Revitalizant gel for compressors and bearingsCompressors · bearings · spindles
- Revitalizant gel for gearboxesGearboxes · transmissions · gear drives
How such units are treated:
About this result:
Limits of this report: The results refer to the plain bearings of hydro unit KhG-3 at HPP “Beli Izvor” and to the gearbox of lathe S 8 M; on other units and duty cycles the figures may differ. The treatment was performed by MAY Ltd., Plovdiv — a XADO distributor.