Shaft seals are designed for just about any type of machinery that has a rotating part of any kind. It is needed to seal liquids, oil, grease, or any type of lubrication. There are several applications for a seal, and it may vary from one industry to another. Shaft seals also come in various sizes to fit small or large shafts in the different parts of a machine. Learn about wellendichtring, and check out a company that provides high-quality shaft seals.
Shaft seals, also known as oil seals, are essential parts of any rotating or moving machine. They find a great deal of usage in hydraulic cylinders as well as gearboxes. The purposes of shaft or oil seals include: to serve as a physical barrier holding the lubrication where it is bound to be, to prevent the lubricant from leaking with the high pressure of the oil, and to block dirt or other contaminants to enter the system that contains the lubrication.
An oil seal has a metal ring that that serves as the inner skeleton. This ring provides the structural stability to the seal, making it more efficient in containing the lubrication and preventing any external entity to get into the system. Furthermore, the outer surface of the oil seal is made of nitrile rubber and durable materials depending on the application for the shaft seal.
Additionally the shaft seal has spring on its lip that provides more support and security to the seal itself. It also prevents leakage of the oil and entry of outside contaminants.
Like what was mentioned above, the materials that are used for the outer skin of shaft seals depends on the applications. The most common material is nitrile rubber. Other materials that are being used include silicone (for light load applications), polyacrylate, PolytetraFluroEthylene, and Viton. The latter is the material that is utilized in places where there is a high temperature.
Requirements for the proper working of oils seals
In order for the oil seals to work properly, the shafts where they will be attached to should be ground with the surface roughness. Ideally, it must be anywhere between 0.2 – 0.8 microns. The shaft should also be hardened enough to prevent the formation of depression from the pressure that is exerted by the spring on the lip of the seal. Also, it is necessary that the lip is greased to prevent it from contacting directly with the shaft.