Skeleton oil seal is a kind of sealing element widely used in mechanical equipment, mainly used to prevent oil leakage and prevent impurities from entering the mechanical system. The following is the basic principle and structural composition of the skeleton oil seal:
1. Basic principles
The working principle of the skeleton oil seal is mainly based on the close contact and friction between the seal lip and the shaft. Its main functions include:
Prevent oil leakage: The close contact between the seal lip and the shaft prevents the oil from leaking outwards from the shaft and ensures the normal lubrication of the mechanical parts.
Prevent entry of impurities: The structural design of the seal lip effectively prevents external impurities and moisture from entering the mechanical system, protecting the internal components from contamination and erosion.
2. Structure composition
The skeleton oil seal is usually composed of the following main parts:
Metal skeleton:
Material: Usually made of mild steel or stainless steel, providing sufficient strength and rigidity to support the entire oil seal structure.
Function: The metal framework is the base of the oil seal, ensuring that the oil seal maintains its shape and stability during installation and use.
Rubber seal lip:
Material: Usually used nitrile butadiene rubber (NBR), fluorine rubber (FKM) or polyurethane (PU) and other materials, with good oil resistance, wear resistance and temperature resistance.
Structure: The sealing lip is V-shaped or lip shaped, which can closely fit the shaft surface to provide good sealing effect.
Function: The sealing lip is the core part of the skeleton oil seal, which realizes the sealing function by contacting with the shaft surface.
Spring:
Material: Usually stainless steel, with good elasticity and corrosion resistance.
Structure: The spring is spiral or corrugated, fixed on the metal skeleton and used to seal the inside of the lip.
Function: The spring provides radial pressure to keep the seal lip in close contact with the shaft surface at all times, ensuring the sealing effect.
Dust lip (optional) :
Material: same as rubber seal lip.
Structure: The dust-proof lip is located on the opposite side of the seal lip and is lip-shaped.
Function: The dust-proof lip is mainly used to prevent external impurities and moisture from entering, providing additional sealing protection.
3. Working mechanism
Static seal: In the static state, the radial pressure of the spring makes the seal lip close to the shaft surface, forming an initial seal.
Dynamic seal: When the shaft rotates, the seal lip automatically adjusts the fitting state through the action of friction and centrifugal force to ensure the sealing effect under different working conditions.
4. Key performance parameters
Temperature resistance: Select the appropriate rubber material according to the temperature range of the environment.
Oil resistance: Consider the type of lubricating oil in the mechanical system, select the appropriate oil resistance material.
Wear resistance: Ensure that the seal lip will not fail due to wear during long-term use.
Elastic recovery: The elastic recovery of the spring affects the sustained pressure of the seal lip against the shaft surface.
5. Installation precautions
Cleanliness: Before installation, ensure that the surface of shaft and oil seal seat is clean and free of impurities and burrs.
For medium: During installation, ensure that the oil seal is aligned with the center line of the shaft to avoid seal failure caused by eccentric installation.
Lubrication: Apply an appropriate amount of grease to the seal lip before installation to reduce friction and wear.
By understanding the basic principle and structural composition of the skeleton oil seal, its importance and application in mechanical equipment can be better understood. Proper installation and maintenance is essential to ensure the long-term effective operation of the skeleton oil seal.