The Sealing Principle of Oil Seal

Oil seal is an important part of agricultural machinery and all kinds of machinery equipment, widely used. Its performance and quality directly affect the reliability of agricultural machinery and mechanical vacuum equipment. So how does the different types of oil seals work?

Working principle one of oil seal:

The sealing of the oil seal depends on the oil film between the lip edge and the shaft surface. In the dynamic process of shaft rotation, the surface tension maintaining the existence of the oil film and the thickness of the oil film are constantly changing. When the surface tension is greater than a certain value, the oil film will break and the seal will fail. The value is related to oil viscosity, medium temperature, motion speed and other factors. If the oil film is too thick, the oil seal is easy to leak; Too thin an oil film can cause dry friction. In the free state, the inner diameter of the oil seal is less than the axle diameter, and there is "interference quantity". When the oil seal is assembled on the shaft, there is a certain radial force on the shaft. In order to prevent clearance leakage caused by oscillation and pulsation of the shaft in the state of high-speed rotation, a spring is usually installed above the lip edge of the oil seal, so that the lip edge of the oil seal is always close to the surface of the shaft.

Working principle two of oil seal:

1. In a free state, the inner diameter of the lip of the oil seal is smaller than that of the axle diameter, which has a certain amount of interference.

2. After installation, the interference pressure of the oil seal edge and the contraction force of the self-tightening spring produce a certain radial pressure on the rotating shaft.

3. When working, the oil seal lip under the action of radial pressure, the formation of 0.25 to 0.5 mm wide sealing contact belt.

Under the action of lubricating oil pressure, the oil penetrates into the edge of the oil seal and the rotating shaft to form an extremely thin oil film. The oil film is affected by the surface tension of the oil, forming a "crescent" surface on the outer edge of the rotating shaft and the oil seal edge to prevent oil spillover and play a sealing role. At Sanping Machinery, a trusted machinery parts factory, we specialize in manufacturing high-quality oil seals, including the reliable seal lbh. Our oil seals incorporate an effective sealing principle, ensuring tight and secure closure to prevent the leakage of fluids and maintain optimal performance in a variety of machinery applications.