Screw and centrifugal compressors
The procedure describes the stage-by-stage introduction of “XADO revitalizant gel for compressors and bearings (industrial)” into the standard oil of screw and centrifugal compressors. The purpose of the treatment is restorative repair and wear protection without stopping or disassembling the compressor.
Units covered by the method
02Method
What is treated
- Serviceable screw and centrifugal compressors that have no parts with 100% wear or macromechanical damage.
- Screw and centrifugal compressors that are new or have initial wear (up to 10%) — treatment in 3 stages at the same consumption rate.
When treatment is not performed
- Compressors having parts with 100% wear or macromechanical damage are not eligible for treatment.
Preparation
- Before starting the treatment, flush or replace the fine oil filter elements.
- Replace the oil in the lubrication system if the residual oil life is less than 40%.
- Before starting the treatment, take measurements of the main operating characteristics of the compressor (see measurements).
What is measured before and after
| Parameter | Instrument | How and when |
|---|---|---|
| Vibration level at fixed points in the vertical, horizontal and axial directions (vibration acceleration, vibration velocity, vibration displacement) | Vibrometers | It is recommended to measure the vibration level near the bearing assemblies or at specially provided monitoring points on the housing of the screw pair. Measured before the start of the treatment and after completion of the full cycle. |
| Power consumption (current draw) of the electric motor with the compressor unloaded | Clamp meter, wattmeter or multi-parameter instrument for monitoring electrical parameters | Measured before the start of the treatment and after completion of the full cycle. |
| Power consumption (current draw) at a fixed pressure and in compressor idle mode | — | Measured before the start of the treatment and after completion of the full cycle. |
| Oil pressure in the compressor lubrication system at a fixed operating temperature | Standard or test pressure gauge | Measured before the start of the treatment and after completion of the full cycle. |
What the reports on these components showed
- Increased electric power consumption33 cases · median 9 %, 44 values
- Loss of compression7 cases · median 13 %, 8 values
- Elevated vibration23 cases · median 46 %, 12 values
- Increased fuel consumption4 cases · median 14 %, 4 values
- Increased clearances and backlash10 cases · median 26 %, 2 values
- Elevated operating temperature13 cases · median 20 %, 11 values
- Oil pressure drop8 cases · median 75 %, 1 value
Consolidated register of the evidence base →
Dosage rates
| Compound | Rate | How and when |
|---|---|---|
| XADO revitalizant gel for compressors and bearings (industrial) | 0.8 mL per 1 litre of standard oil for one treatment stage | Rate per each stage; 5 stages in total, for new compressors or those with initial wear (up to 10%) — 3 stages at the same consumption rate. |
| Standard oil for dissolving the gel | 1 part of the gel being dissolved to 5 - 10 parts of oil heated to 50–60°C | The oil is poured into a separate container, and the prepared amount of gel is dissolved in it. |
Treatment stages
- Prepare “XADO revitalizant gel for compressors and bearings (industrial)” at the rate of 0.8 mL per 1 litre of standard oil. Pour a small amount of standard oil heated to 50–60°C into a separate container (1 part gel to 5 - 10 parts oil), dissolve the prepared amount of gel in it and mix thoroughly until completely dissolved. Introduce the resulting mixture into the oil filler neck of the screw or centrifugal compressor. The compressor is then operated in its normal mode.Start of counting the compressor's total operating time
- Carry out the stage in the same way as the first one.18–24 hours of total compressor operating time between stages
- Carry out the stage in the same way as the first one.18–24 hours of total compressor operating time between stages
- Carry out the stage in the same way as the first one.18–24 hours of total compressor operating time between stages
- Carry out the stage in the same way as the first one.18–24 hours of total compressor operating time between stages
After treatment
- The treatment of the compressor is considered complete after 500 hours of total compressor operating time, counted from the start of the first treatment stage.
- After completion of the full cycle, measurements are taken of the main operating characteristics of the compressor: vibration level, power consumption (current) of the electric motor with the compressor unloaded, power consumption (current) at a fixed pressure and in idle mode, oil pressure in the lubrication system at a fixed operating temperature — in order to determine the effectiveness of applying XADO revitalizant compounds.
Points to watch
- Screw and centrifugal compressors are treated only with “XADO revitalizant gel for compressors and bearings (industrial)”.
- The gel is introduced only in dissolved form: a solution in standard oil heated to 50–60°C, mixed until completely dissolved.
Compounds for these units
- Revitalizant gel for compressors and bearingsPiston, screw and centrifugal compressors; rolling and sliding bearings running in an oil bath; machine-tool spindle units and slideways.
Methods for specific machines
- EHS 250/160 screw compressorScrew compressor with a capacity of 20 m³/min. The only machine among those analysed where treatment is carried out in four stages.
- Screw refrigeration compressorA refrigeration unit: its output is judged not by how fast the receiver fills, but by how often the compressor starts up to hold the temperature in the chamber.
- Turbocompressor K-250A large turbocompressor station. The effect is measured not by pressure but by electricity: how many kilowatt-hours are spent per thousand cubic meters of air.
- 4VRZ turbocompressor stationTurbocompressor station with a step-up gearbox (multiplier). In addition to the electrical parameters, the tooth thickness of the multiplier is measured.
Reports on this unit
- ArcelorMittal Kryvyi Rih · 2011↓ 2.8–3.1% — power drawn by the drive under load, 2578–2692 → 2506–2609 kW
- OJSC Stoylensky GOK · 2011↓ 3.0% — power consumption in unloaded mode, 467.12 → 455.11 kW
- Kharkiv Yeast Plant JSC · 2009↓ 12–18% — vibration level at the rotor bearing assemblies and the base supports
- JSC “Rzhevsky Sakharnik” · 2009↑ 7–17% — diesel cylinder compression, 560 rpm, 23–29 → 26–30 kgf/cm²
- PP “Dyvany-Mebli” · 2009↑ 10% — compressor output, charge-up to 6.5–8 atm, 55 → 50 s
- Gorlovskiy Machine-Building Plant · 2006↓ 6% — power draw under load, 648.0 → 609.0 kW
Source: Instructions for the use of XADO revitalizant gels IE-24.6-25612000-005-2008, pages 9–10.