一、the tightness of the vacuum pump oil

     Vacuum pump oil needs to have a suitable viscosity, at low temperature can make the vacuum pump start quickly, at high temperature vacuum pump oil can have good sealing, in the pump vacuum pump oil has a low temperature rise. It does not contain lightweight volatile components, reducing the oil return rate of the vacuum pump during use.

二、Saturated vapor pressure of vacuum pump oil

   Saturated vapor pressure is one of the more critical indicators of vacuum pump oil. In a closed vessel at constant temperature, the pressure when the vapor-liquid phase reaches dynamic equilibrium is called saturated vapor pressure.

   The saturated vapor pressure of the oil should be as low as possible, and at the maximum operating temperature of the pump, the saturated vapor pressure should still be low enough, and it should be lower than the limit pressure specified by the vacuum pump.

三、Lubricity of the vacuum pump oil                              

    Friction wear of the friction surface, surface fatigue wear and corrosion wear are all related to lubrication conditions. Good performance of vacuum pump oil is conducive to inhibiting corrosion wear; Can effectively reduce adhesion wear and surface fatigue wear; Fluid lubricants have a cleaning effect on the friction surface and also reduce friction wear. Reduced frictional resistance to conserve energy and reduce wear to extend mechanical life.

四、Cooling performance of vacuum pump oil

    Reducing the temperature of the friction surface is an important role in lubrication. When the friction surface is moving, it must overcome the friction force and work, and the work consumed on overcoming the friction force is all converted into heat, and the result will cause the friction surface temperature to rise. The magnitude of the frictional heat is related to the lubrication state, with the heat of high viscosity being the greatest and the heat of low viscosity being the least, while the heat of boundary friction is somewhere in between. It can be seen that the vacuum pump oil with the right viscosity can not only achieve liquid lubrication and reduce the generation of frictional heat, but also bring frictional heat out of the pump body in time.

五、The purity of the vacuum pump oil

    The friction pair inevitably comes into contact with the surrounding medium, causing corrosion, rust and destruction. The excellent performance of vacuum pump oil requires that the friction area be cleaned and removed as much as possible; Resistant to corrosion and rust and protects friction surfaces from oil deterioration or external erosion.

六、Oxidation stability of vacuum pump oil

    Oxidation stability indicates the anti-aging performance of lubricating oil, and this special performance requirement is required for vacuum pump oil operated on industrial assembly lines. All lubricating oils have different degrees of automatic oxidation tendencies according to their chemical composition and different external conditions. In the presence of air (or oxygen) and metal catalysts, the oxidation time of vacuum pump oil at a certain temperature will occur in the acid value, viscosity and precipitation formation of the oil. Oxidation occurs with the use process, so that some aldehydes, ketones, acids and colloids, asphaltenes and other substances are gradually generated, and oxidation stability is to inhibit the above-mentioned substances that are not conducive to the use of oils.

七、Anti-emulsification resistance of vacuum pump oil

    Vacuum pump in the operation process, the system of moisture and cold gas will be discharged into the pump oil, if the vacuum pump oil resistance is not good, it will be mixed with the water to form an emulsion, so that the water is not easy to release from the bottom of the circulating tank, which may cause vacuum drop and poor lubrication.

    Therefore, emulsification resistance is an important physical and chemical property of industrial lubricants. Especially in the vacuum drying process used in the pharmaceutical, food, ceramics and other industries, the anti-emulsification performance of the pump oil is more critical. The pump oil and water separation ability with good emulsification resistance is strong, and the water vapor and condensing gas will discharge part of the water vapor by opening the gas ballast valve. In addition, the anti-emulsification ability of low viscosity pump oil is better than that of high viscosity pump oil.

八、Foam resistance of vacuum pump oil

    Vacuum pump in the process of operation, due to the presence of air, often produce foam, especially when the oil contains surface activity additives, it is easier to produce foam, and the foam is not easy to disappear. Foam generated during the use of lubricating oil will destroy the oil film, not only sintering or increasing wear on the friction surface, but also promoting oxidative deterioration of the lubricating oil. The gas in the operating vacuum system will be continuously discharged through the sealed vacuum pump oil layer, and the exhaust gas will generate a large number of bubbles on the surface of the oil layer and overflow from the exhaust hole of the pump, resulting in oil loss and equipment pollution. Pump oil with anti-foaming agent has significantly improved the anti-foaming effect.