Concept and application of ultimate vacuum
Ultimate vacuum concept
The full name of "Ultimate Vacuum" is "Ultimate Vacuum Degree", which refers to the maximum vacuum that a vacuum pump can reach.
"Ultimate vacuum" means that in this state, no matter (including molecules, atoms, etc.) exists. This is a state that exists only in theory and is actually impossible to achieve.
For example, a vacuum pump with weak pumping capacity can only reduce the gas pressure in a closed container from 100KPa to 95KPa after an infinite time. Then 95KPa is the ultimate vacuum of this pump
Another example, there is a vacuum pump with strong pumping capacity, which can reduce the air pressure from 100KPa to 10KPa, then 10KPa is the ultimate vacuum of this pump.
Application of ultimate vacuum
"Ultimate vacuum" is an important parameter of a vacuum pump. It is a characteristic value that reflects the pumping capacity of the pump. It is a value related to the vacuum pump. Different vacuum pumps can have different "ultimate vacuum" degrees.
The "theoretical vacuum" is a concept in theoretical research, and it is an ideal vacuum state refined by excluding the influence of various practical factors. After the vacuum container is fully evacuated, it stabilizes at a certain degree of vacuum, which is called the ultimate vacuum. Generally, the vacuum vessel must undergo gas refining for 12 hours, and then vacuuming for 12 hours,the last hour is measured every 10 minutes, and the average value of the 10 times is taken as the ultimate vacuum value.