Various means are used to extend the life of the refrigeration equipment. With them, it will be possible to reduce the wear of the rubbing elements and reduce the friction force of the parts. For this, refrigeration oils are used. Lubrication is needed, since the tightness of the device is improved with it, particles that have penetrated inside are eliminated. Lubrication also removes excess heat from parts. Read more about this tool in the article.
Manufacturers use synthetic oils and mineral fluids in plants. If you perform a comparison of characteristics, the first view is considered the best. Liquids have a low pour point, high hermetic stability. Synthetic-based refrigeration oils are used to lubricate parts; when mixed with refrigerants, they are resistant. With them, the materials from which the elements of the refrigeration units are made are not destroyed.
Appointment
Refrigeration oils not only reduce the level of wear of parts, but are also intended for other purposes:
- Partial heat dissipation. The oil has a good heat capacity.
- Removal of small particles. Dust and other impurities are trapped in oil, so they do no harm to the equipment.
- Improved tightness. Using a viscous fluid, the gaps between the elements are filled so that moisture and air do not get inside.
Therefore, it is important to replace the fluid. Moreover, this can be done both independently and by contacting a service center.
Characteristics
When choosing oil, you need to consider not only the brand and value. Each equipment requires its own products, taking into account its properties. The main parameters include density, pour point. It is also important to find out:
- The acidity of the refrigeration oil.
- Cloud Point
- Chemical stability.
- Surface tension.
- Solubility.
- Miscibility
- Viscosity.
Since there is a compressor in the refrigerator, you need to choose oil with a suitable consistency. For example, for equipment R134a, a tool with astringent properties in the range of 15-68 centistokes is used.
The choice
When choosing refrigeration oils, keep in mind that refrigerants are compatible with synthetic products. There is a certain dependence. Since the oils are in contact with refrigerants, some requirements are imposed on them:
- A quality product does not accumulate in the evaporator. It circulates through the system, and even with low temperatures it will be liquid.
- The product must be viscous. Products poured into the refrigeration unit must have a system sealing function. It should be borne in mind that the temperatures in the compressor are high.
- The product must be suitable for the specific type of refrigerant.
- The flocculation temperature of high-quality oil is quite low.
- The tool should have a minimum acid number. This applies to refraction, toxicity, temperature.
In most installations, the refrigerant is freon and freon. Properly selected refrigeration oil ensures that the compressor will function smoothly. The component is mixed with the refrigerant. If it has the classes of CFCs, HFCS, HFCs, then different types of refrigerant fluids should be used in the installation.
Such products are presented in the form of mixtures made from synthetic hydrocarbons and mineral oils. There are no additives in such products. These are special oils for refrigeration units for which standard mineral fluids cannot be used. Semi-synthetic products are suitable for almost all equipment used in household and industrial applications.
Bitzer refrigeration oils suitable for modern equipment are in demand. They reduce the wear of rubbing parts. With them it will be possible to extend the service life of installations.
Mineral oils
R12 and R22 refrigerants are used with minerals. These products are inexpensive. The oils of naphthenic-based refrigerators are refined, therefore they are of better quality.
Products do not include additives. Base oils are used for its manufacture. They are cleaned, which results in a product that is excellent for lubrication. The following fluids Shell Clavus G and Mobil Gargoyle Arctic, Lunaria FR and Suniso GS are common today. These products are approved by leading compressor manufacturers.
Semi-synthetic and synthetic products
Virginia AB, Shell Clavus SD 22-12 is suitable for filling. With them, the devices function perfectly. Synthetic oils for refrigeration compressors have low hygroscopicity, they are compatible with polymers. Of the characteristics, excellent thermal stability can be distinguished.
Liquids in contact with non-ferrous metals create their protection against corrosion. The product has excellent electrical insulating properties. The oil has excellent hydrolysis resistance. New synthetic fluids were created at the time HFC refrigerants were introduced. They are considered safe for the ozone layer. These include:
- R23.
- R134a.
- R404a.
- R407c.
- R410a.
- R507
These products on a synthetic basis guarantee a long period of operation of the equipment, since insoluble precipitate does not appear. This means that the internal parts of the system will be clean. For piston mechanisms it is necessary to buy products with viscosities in accordance with ISO 22, 32. Fluids 46 and 68 are also used. They are mixed with freon and can be used for mixing with freon. If they are used for systems with dry evaporators, then liquid is returned to the compressor.
Preparation
Repair should be carried out after consulting with a specialist. You must read the instructions. This must be done in case of warranty service, because then you can contact the service center. It is necessary to prepare everything you need:
- Charging hose.
- Reliable pressure gauge.
- Vacuum pump.
Fluid replacement
Refueling is based on the following steps:
- Create a vacuum in the compressor. Therefore, shut off 2 service valves on the installation. A vacuum pump is connected to one, it must work until the minimum positive pressure is set. If the value reaches 0.1 bar, the pump must be switched off. Then you need to remove the oil plug. A hose equipped with a shut-off valve must be screwed.
- It is necessary to open the suction valve so that the refrigerant vapor enters the compressor. When there is a slight positive pressure, the valve must be closed.
- On the rear hose, which is needed to remove air, it is important to open the shut-off valve. The end of the hose must be lowered to the bottom of the container with oil, close the shut-off valve.
- Then the vacuum pump starts up . When the pressure is less than atmospheric, you need to open the shut-off valve. There is an oil supply to the unit, this can be controlled using the viewing window. It is necessary to close the shut-off valve when the oil rises to the required level.
- The pump stops working. The valve should be opened slightly to create positive pressure. The charging hose must be disconnected. At the end, screw in the oil plug.
Output
Subject to the technology, moisture and air will not appear in the installation. Need to add fluid? Use a syringe for this. The system needs an oil change, for refrigeration compressors you need to buy it in special stores. Work is also being carried out in service centers. Properly performed procedure extends the life of refrigeration equipment.