Selection and Attention Points of Lubricating Oil for Refrigeration Machines
I. Introduction
Refrigeration machines are widely used in the modern industrial production. Refrigerating oil plays an important role in the operation of refrigeration machine. The performance of the ancillary equipment in the refrigeration system depends on the selection and usage of refrigerating oil. In order to ensure the normal operation of the refrigeration machine, it is necessary to select a more suitable lubricating oil. This article will analyze the selection and attention points of lubricating oil for refrigeration machines.
II. Selection of Lubricating Oil for Refrigeration Machines
1. Performance
It is necessary to choose a lubricating oil with good performance. Generally, refrigeration oil should have good thermal stability and oxidation stability. That is to prevent the spontaneous oxidation of the lubricating oil within a certain temperature range long-term in the refrigeration system. Therefore, the lubricating oil of different temperature grades varies according to temperature range. It should have a strong antioxidant ability in order to prevent corrosion of the metal material in the refrigeration system caused by acid components generated by oxidation. Meanwhile, it should have excellent viscosity-temperature performance, better low-temperature fluidity and lubrication performance of the machine parts at low temperature.
2. Refrigerant Compatibility
The refrigeration oil must be completely compatible with the refrigerant used in the refrigeration system. While refrigeration oils are used in the system, if their volatility is high, the lubricating oil can be easily absorbed by higher boiling point refrigerants, resulting in increased system oil capacity. If the lubricating oil is not compatible with the refrigerant, it will cause poor heat transfer performance, but also cause slagging.
3. Low Foam Stability
The foaming stability of the refrigerant oil is the stability of oil when exposed to air. Under normal circumstances, after the refrigeration system is filled with refrigeration oil, the oil continuously generates a large amount of tiny bubbles and foam due to various disturbances due to local turbulence or eddy currents. In the refrigerant cycle, foam or emulsification not only causes insufficient cooling and increased motor load, but also causes eye-catching contaminants in the system, which affects the heat transfer effect of the heat exchange surface in the system, increases abrasion of the machine parts, and affects the normal operation of the system.
4.Good Water Resistance
The refrigerant oil generally needs to have good water resistance. Generally, the isolation valve resistance of the refrigeration system should be higher than 10. If the water content is more than 5%, it will cause metamorphic slagging, resulting in poor heat transfer performance, increased system pressure and other conditions.
III. Attention Points for Lubricating Oil for Refrigeration Machines
1. In the process of daily operation of the refrigerating machine, the oil level should always be maintained in the middle of the indicators. When the oil volume is insufficient, it is necessary to fill it in time so as not to cause the machine to run without oil for a long time.
2. Since refrigerating oil is easy to absorb moisture when exposed to the atmosphere, strict attention should be paid to the storage and transportation of oil, and try to avoid long-term exposure of oil.
3. The refuelling process of the refrigeration machine must be carried out in a clean environment. It is not suitable to directly use the oil introduced into air. It must be scrubbed with dry compressed air and refueled only after being filtered.
4. Clean oil should be used after the maintenance and replacement of refrigeration machines.
5. Always check and clean up the oil cup. The exhaust gas should be discharged every three months.
6. When it is found that the oil volume is decreasing, it is necessary to determine whether it is caused by physical losses or oxidation losses.
IV. Conclusion
The selection and attention points of lubricating oil for refrigeration machines are discussed in this article. Refrigeration machine require a lubricating oil with good performance, refrigeration compatibility, low foam stability and good water resistance. Meanwhile, attention should be paid to the daily maintenance of refrigeration machines and the correct use of oil. We hope that this article can help to better maintain the refrigeration equipment and extend the service life of the equipment.
