There is a British Standard laid down for the control of synthetic rubbers. BS 3574 (1989) helps to determine shelf life – for instance, Nitrile (NBR) and Polyacrylic (ACM) are Group ‘B’ rubbers and have a 7-year life, whilst Silicone (VMQ) and Fluoroelastomers (Viton®) are Group ‘C’ rubbers and have a 10-year shelf life. PTFE and Leather do not come into this category but like the others should be kept in the original packing for as long as possible away from direct light, dust, and humidity. Ozone, which can also be produced by battery-driven forklift trucks has a very bad effect on synthetic rubbers. Finally, protect the sealing lip – DO NOT hang the seals on nails, wire etc.
Oil seals are commonly used in engines, gearboxes, and other rotating machinery to prevent the leakage of oil from shafts and bearings. They are typically made from rubber or elastomeric materials that are resistant to oil and heat. The seal is installed in a housing or bore that is larger than the shaft, and it is pressed against the shaft to create a tight seal.
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.
There are many different materials used to manufacture oil seals.