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What is an oil seal?
An oil seal, or shaft seal, stops oil, grease, and other substances from leaking along a rotating shaft. Its leakage prevention relies on sealing components. Choose component materials based on the application scenario. A common component in gearboxes, hydraulic cylinders, and related machinery.
The role of the oil seal
Oil seals (shaft seals) are key components for preventing mechanical leakage. They stop oil and grease from leaking along the rotating shaft. They also block outside impurities.
They work well in gearboxes and hydraulic cylinders. This keep equipment stable and reduce failures.
Oil seal structure
Oil seals have three key parts: the sealing element, the metal skeleton, and the auxiliary seal.
1. Sealing element: It is the core component of anti-leakage. It primarily uses elastic materials such as nitrile rubber (NBR), fluorine rubber (FKM), and silicone rubber (VMQ).
It adheres firmly to the shaft surface because of its elasticity. This forms a strong seal. It stops medium leakage and keeps out impurities.
Choose materials based on the application:
Nitrile rubber is cheap and oil-resistant, good for regular oil use.
Fluorine rubber resists high temperatures and corrosion, making it ideal for tough conditions.
Silicone rubber works well in a wide temperature range.
2. Metal Frame: A manufacturer makes this sturdy support from thin steel plate stamping. It protects your oil seal well. It combats the forces that threaten to shift sealing positions during installation.
Not a pretty face. It can handle pressure shocks during operation. This keeps the sealing element tight against the shaft surface. This unyielding frame is the cornerstone of your oil seal’s structural strength.
3. Auxiliary Sealing Structure: This part has the dust lip, return groove, spring, and more.
The dust lip keep out dust and dirt, which extends the life of the seal.
The return groove helps guide leaked oil back into the equipment while the shaft spins. This boosts the anti-leakage effect.
Some oil seals also have springs that push against the seal. This pressure helps offset wear and keeps the seal tight.
Oil Seals from KODA Seals and O-Rings Company
DODA O-Rings and Seals provides a complete range of oil seals in standard sizes. We also customize oil seals to meet your needs. If you’re an oil seal dealer or user, contact us today. Speak with our team, request a free quote, or visit oilseal-china.com to see our products.
