Why lubricant oil has a high viscosity level?
Lubricants are widely used these days, mainly because they are widely applied in industries and form an important part of the whole system. At present, people try to spend less on lubricant oil for their machines as much as possible. A common question is why lubricant oil has a high viscosity level.
Definition of viscosity
Viscosity is a measure of a fluid’s resistance to flow, and it is commonly used to quantify the consistency of fluids such as oil, water, and blood. The higher the fluid’s viscosity, the greater its resistance to flow.
The term “viscosity” comes from the Latin viscum, meaning mistletoe, and originally referred to the sticky resin secreted by mistletoe plants. The earliest known use of the word in English was in 1382, in work by Geoffrey Chaucer. Viscosity is caused by the intermolecular forces between molecules in a fluid. These forces can be attractive or repulsive, and they can be long-range or short-range.
In general, fluids with strong intermolecular forces (attractive or repulsive) have high viscosities, while fluids with weak intermolecular forces have low viscosities. For example, honey has a high viscosity because its molecules are held together by strong, attractive forces; on the other hand, water has a low viscosity because its molecules are only weakly attracted to each other.
Types of viscosity and the measurement of it
Viscosity is a measure of how fluid resists flow. The viscosity, or thickness, of a fluid determines how easily it will flow. There are two types of viscosity: absolute and kinematic.
Absolute viscosity measures a fluid’s resistance to flow under an applied force. It is measured in units of poise or Pascal-seconds (Pa-s).
Kinematic viscosity measures a fluid’s resistance to flow under its weight. It is measured in units of stokes (St) or centistokes (cSt).
The most common way to measure viscosity is with a rotational viscometer. This device consists of a spindle rotating at a constant speed in a fluid sample, and the resistance to rotation is measured and used to calculate the fluid’s viscosity.
Why lubricant oil has a high viscosity level?
There are several reasons why lubricant oil has a high viscosity level.
- One reason is that it helps to protect the engine from wear and tear. Lubricant oil coats the engine parts and creates a barrier, reducing friction and wear.
- Another reason is that high-viscosity oil provides better cooling for the engine. When the engine is running, the oil circulates and carries away heat, helping to keep the engine cool.
- Finally, high-viscosity oil helps to reduce fuel consumption. Because the oil coats the engine parts and reduces friction, less fuel is needed to power the engine.
Conclusion
There are a few key reasons why lubricant oil typically has a high viscosity level. Firstly, it needs to be thick enough to create a barrier between moving parts, and secondly, it needs to withstand high temperatures without breaking down. Therefore, a high viscosity level is essential for ensuring that lubricant oil can do its job properly.
