The basic principle of sealing is straightforward – the flexible lip is held against the rotating part (usually the shaft) whilst the casing (or O.D.) is pressed into the housing or bore and holds the seal in place. The sealing lip needs some form of lubrication to avoid overheating and is usually energized by means of a garter spring.
Metal cased design
Different types of rotary shaft seals are available in the market, including radial lip, axial lip, and mechanical face seals.
Viton Oil Seals - A synthetic rubber and fluoropolymer elastomer, Viton is used to make oil seals that provide resistance in both high temperature, up to 250°C and low compression set components. They also offer a high resistance to chemicals and abrasions, so they can be used in elements that regularly interact with petroleum and solvents.
As type A with dust lip
GV
They are best known for their bright light emission that is far reaching. Their tungsten is encased in a quartz tube filled with xenon gas. They may require more power when turned on but use much less of it to maintain brightness. Moreover, they have a longer lifespan compared to the halogens. They may seem better but they also present some limitations such as being more expensive as far as manufacturing and replacement is concerned. They are not easy to manufacture from their complex design. Their bright light cause a blinding effect to oncoming traffic which is undesirable and can cause dangers on roads.
Rubber or rubber fabric
An oil seal, also known as crankshaft retainer, is a small device, but essential to ensure the proper engine operation. It plays a key role in all moving parts of an engine, acting as a physical barrier. This mechanical seal fulfils the dual purpose of sealing a rotary shaft to maintain the necessary lubrication (avoiding leaks) and preventing other foreign matter from contaminating shafts and bearings in the rotary shaft equipment.