The role of screw oil:

1. Lubrication: The worn debris can be lubricated The oil is taken away, called flushing. The effect of the rinsing effect has a great influence on the wear. The lubricating oil formed between the friction surfaces is very thin, and the metal debris stays on the friction surface to destroy the oil film, and the dry friction causes the abrasive grains to wear.

2. Protection: It can protect against dust and corrosion.

3. Cooling effect: Most of the heat generated by friction is carried away by the lubricating oil, and a small amount of heat is directly emitted by the conducted radiation.

4. Unloading effect: Due to the presence of oil film between the friction surfaces, the load acting on the friction surface is relatively uniform and distributed on the friction surface through the oil film. The effect is called unloading.

The principle of lubricating oil:

1. Setting point: under specified cooling conditions The highest temperature at which the oil stops flowing, which is an important indicator of the low temperature fluidity of the lubricating oil.

2. Pour point: Pour point and pour point are indicators of low temperature fluidity of oil. There is no principle difference between the two, but the measurement method is slightly different. The points are above the freezing point of 2-3 °C.

3. Flash point: The oil is heated under specified test conditions to raise the temperature, some of which evaporate or decompose to produce a flammable gas, when it rises to a certain temperature and When mixed with air, the lowest temperature at which a flash can occur when in contact with the flame is called the flash point.

4. Emulsifying resistance: The anti-emulsification property of oil refers to the property of emulsification of smelting oil or emulsification at one time but rapid decomposition after standing oil.

5. Anti-foaming property: refers to the performance of the foaming volume and the speed of consumption when the air is introduced into the oil or when it is stirred. In the actual use of lubricating oil, due to the action of shock stirring, the air is mixed into the oil, so that the formation of bubbles causes the fluidity of the lubricating oil to deteriorate, the lubricating performance is deteriorated, and even the gas resistance affects the oil supply, so that the machine parts are obtained. Less than lubrication, wear and even sintering.

6. Viscosity: is an indicator of the oiliness and fluidity of oils. Common viscosity indicators are dynamic viscosity and kinematic viscosity.

(1) Dynamic viscosity: Two oil layers each having an area of ​​1 cm2 and a distance of 1 cm away. When one of the oil layers is opposite to the other oil layer at a speed of 1 cm/s The resistance generated during exercise is the dynamic viscosity.

(2) Kinematic Viscosity: The ratio of the dynamic viscosity of a liquid to its density at the same temperature is called the kinematic viscosity.