It varies with the oils viscosity.
300-500 c
The "Pour Point" of engine oil is about -44ºF.
Lubricating oil is NOT volatile.
motor oil has got a boiling point/brake down point of lubricating oil to be 300-370 degrees Celsius. once it has boiled it loses its lubricating properties.
Lubricating Oil Is A Thick Fatty Oil (Especially One To Be Used For Lubricating Factory Machinery)
The pour point is the lowest temperature at which the fuel will flow. Pour point depressant will allow fuel to be used at a lower temperature without problems. Fuel oil must be pumped before it is used and if the viscosity is too high the oil will not flow easily. Pour point depressant might also allow fuel oil to be stored at a lower temperature thus saving some energy that would normally be used to keep it above its pour point. The chemical names of fuel additives are often proprietary and kept a secret, however see the related links for a discussion of pour point depressants.
It is self-lubricating
No, the lubricating oil is a liquid
It was not invented. In fact the Romans had used it so it is nothing new.
Oxidation of lubricating oil is primarily caused by exposure to oxygen in the air, high temperatures, and contaminants such as water and metal particles. These factors can lead to the formation of harmful byproducts that can degrade the oil and reduce its lubricating properties. Regular oil analysis and maintenance can help monitor and prevent oxidation in lubricating oil.
yes
Lubricating oil is used to reduce friction between moving parts and to prevent damage due to excess heat. Lubricating oil also carries away sludge preventing the erosion of moving parts.