Materials

Material	Advantages	Disadvantages	Operating Range & Appearance
Carboxylated Nitrile - XNBR	Similar Properties to standard NBR. Tough. Abrasion resistant.	Reduced cold temperature flexibility.
EPDM	Excellent resistance to heat, water, steam, ozone and sunlight	Inadvisable for petroleum service	-50° C to +150° C
Fluoroelastomer	Wide temperature range - 50/+250 ºC. Flexibility. High absorbance of lubricant minimises friction.	Low tear strength. Poor abrasion. Poor resistance to oxidised oils or to EP additives.	Temperature range is -50°C to 250°C, Generally red, feels softer and more flexible than other materials
Nitrile	Versatile. Oil and abrasion resistant. Good low swell characteristics. Temperature range Good processing. Relative low cost.	Limited high temperature capability. Limited high speed. Not suitable for synthetic oils such as phosphate ester.	Temperature range is - 40°C to 120°C Other formulations can cope with higher and lower temperatures Generally black but red is also common as Silicone substitute
Polyacrylate - ACM	High temperature 150 ºC. Good resistance to oils. Good ageing. Low price.	Lower resistance to water. Poor processing. Low temperature range.	Temperature range is - 30°C to 150°C Black with similar appearance to Nitrile
Silicone	Wide temperature range - 50/+250 ºC. Flexibility. High absorbance of lubricant minimises friction.	Low tear strength. Poor abrasion. Poor resistance to oxidised oils or to EP additives.	Temperature range is -50°C to 250°C, Generally red, feels softer and more flexible than other materials
Leather	Tough. Good abrasion resistant. Good tensile strength. Good low-lube run. Polishes shaft. OK with most oils.	Poor resistance to Water. Non-homogeneous matrix, very variable. Becoming scarce and very expensive.	Will handle temperatures from -100°F to 200°F Safer range is - 65°F to 200°F Colour brown/beige and fibrous Generally black but red is also common as Silicone substitute
Felt	Retains grease quite efficiently. Excludes dust & dirt well.	Unable to seal oil which seaps through the matrix. Will absorb water causing shaft rusting. May trap metal or abrasive particles damaging the shaft.	Temperature range is - 65°F to 200°F. White, grey or black. Very fibrous mat.