Skeleton oil seal specification

       Structure and sealing principle of skeleton oil seal

       The skeleton oil seal is relatively simple and generally consists of three parts: an oil seal, a reinforcing skeleton and a self-tightening coil spring. The sealing body is further divided into a bottom portion, a waist portion, a cutting edge and a sealing lip according to different parts. Generally, the skeleton oil seal in the free state has a smaller inner diameter than the shaft diameter, that is, has a certain "interference". Therefore, after the oil is encapsulated in the oil seal seat and the shaft, the pressure of the oil seal edge and the contraction force of the self-tightening coil spring exert a certain radial tightening force on the shaft, and after a period of operation, the pressure will rapidly decrease or even disappear. Therefore, the spring can compensate the oil seal self-tightening force at any time.

       Sealing principle: This oil film has fluid lubrication properties due to the oil film controlled by the oil seal edge between the oil seal and the shaft. Under the action of the surface tension of the liquid, the stiffness of the oil film just forms a crescent surface at the contact end of the oil film and the air, preventing the leakage of the working medium, thereby achieving the sealing of the rotating shaft. The sealing ability of the oil seal depends on the thickness of the oil film on the sealing surface. If the thickness is too large, the oil seal leaks; if the thickness is too small, dry friction may occur, causing oil seal and shaft wear; if there is no oil film between the seal lip and the shaft, it is easy to cause heat and wear. .

       Therefore, when installing, it is necessary to apply some oil on the sealing ring, and at the same time ensure that the skeleton oil seal is perpendicular to the axis of the shaft. If it is not vertical, the sealing lip of the oil seal will drain the lubricating oil from the shaft, which will also lead to excessive sealing lips. abrasion. During operation, the lubricant in the casing slightly exudes a little to achieve a state in which an oil film is formed at the sealing surface.https://www.supplyforever.com/