Figure 14.4. Effect of aeration on oil aging.5 Chart shows percent retained elongation after aging for 28 days at 150°C in Mobil 276.
Oil seal characteristics
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.
Standard 3760/3761
VMQ (silicone)
In piping systems, square rubber gaskets are used to seal joints and connections, preventing leaks and ensuring the integrity of the system
. These gaskets are available in different thicknesses and sizes to accommodate various pipe diameters and pressure ratings.