Introduction
Lip seal is one kind of contact type seals. During operation, lip seal is like other
transmission elements (e.g. bearing or gear), which needs to establish a thin film to decrease
wear and contact friction force between lip and shaft. So that the seal can maintain the
sealing function and can have a longer life. In order to have a better understanding on oil seal,
we will introduce some basic concepts and characteristics of lip seals below.
1.2 Seal introduction
The main function of a seal is to prevent the fluid (e.g. lubricant or air) to leak from
shaft and housing. It can also prevent dust and mud to contaminate the housing. If dust and
mud invade the housing, the life of transmission machinery will decrease greatly. The figure
below is an illustration of a seal installed in one part of engine. In the early stage, the rotary
shaft seal is made of leather. It is found that the rubber material properties for oil seal design
is much better than leather. So that after the War Ⅱ, the seal made of rubber is widely used.
In these two decades, automotive, aerospace, and other industries require the seals to resist
higher temperature, pressure, and speed. This makes engineers have to do more research on
material, structure, and function tests to improve the sealing function.
Lip seal is one kind of contact type seals. During operation, lip seal is like other
transmission elements (e.g. bearing or gear), which needs to establish a thin film to decrease
wear and contact friction force between lip and shaft. So that the seal can maintain the
sealing function and can have a longer life. In order to have a better understanding on oil seal,
we will introduce some basic concepts and characteristics of lip seals below.
1.2 Seal introduction
The main function of a seal is to prevent the fluid (e.g. lubricant or air) to leak from
shaft and housing. It can also prevent dust and mud to contaminate the housing. If dust and
mud invade the housing, the life of transmission machinery will decrease greatly. The figure
below is an illustration of a seal installed in one part of engine. In the early stage, the rotary
shaft seal is made of leather. It is found that the rubber material properties for oil seal design
is much better than leather. So that after the War Ⅱ, the seal made of rubber is widely used.
In these two decades, automotive, aerospace, and other industries require the seals to resist
higher temperature, pressure, and speed. This makes engineers have to do more research on
material, structure, and function tests to improve the sealing function.