


What are Oil Seals and how do they work?
A typical oil seal consists of three common parts: an outer ring, the sealing element, and a spring. The exterior metal ring component provides strength and rigidity to the oil seal in the bore or recessed groove. Attached to that ring is the sealing element. This flexible interior component of the oil seal, the O-ring, prevents any fluid leaks between the shaft and housing. A spring ensures the constant pressure that deforms the O-ring, creating a reliable seal while maintaining radial force on the shaft.

The most common oil seals are the ERIKS types R, RST, M and MST, which correspond respectively to types A, AS, B and BS according to DIN 3760/ISO 6194.

Of course, all rubber materials and seals will provide a range of benefits; however, you will need to consider chemical compatibility, sufficient temperature ranges, pressure ranges, and more.

5. TYPES OF FLUID: Numerous oil seals can interact with oils, fuels, grease, water and more. However, know exactly what type of fluid the rotary shaft seal will be in contact with will ensure the longevity of the seal and the machinery.
The spring shown in the figure is known as a garter spring, and it maintains tension on the sealing lip of the seal. Garter springs are closed coil springs used in the form of a ring, the ends of which are connected together as shown in Figure 2.10.

