ABSTRACT
The majority of seals used in industrial applications are either “elastomer contact” or “elastomer energized.” Elastomer contact seals are those that rely solely on elastomer contact for sealing. Elastomer energized seals are those that use the elastomer to force a plastic seal element against one of the faces that must be sealed. Because both types of seals utilize an elastomer as an essential
2.1 Introduction ............................................................................................................................ 53 2.2 Seal Chemistry .......................................................................................................................54 2.3 Elastomer Compounds ............................................................................................................ 55 2.4 Molding ................................................................................................................................... 57 2.5 Elastomer Seal Materials ........................................................................................................ 59
2.5.1 Nitrile .......................................................................................................................... 59 2.5.2 Ethylene Propylene .....................................................................................................60 2.5.3 Urethane ...................................................................................................................... 61 2.5.4 Fluorocarbon ............................................................................................................... 61
2.6 Seal Compatibility .................................................................................................................. 62 2.6.1 Empirical Prediction of Elastomer Compatibility ...................................................... 62 2.6.2 Elastomer Compatibility Tests ....................................................................................64 2.6.3 Guidelines ................................................................................................................... 67
2.7 Physical Properties .................................................................................................................68 2.8 Seal Compatibility Test Program............................................................................................ 71
2.8.1 Test Conditions and Specimens .................................................................................. 72 2.8.2 Dimensional Measurements of Specimens ................................................................. 73 2.8.3 Hardness Change ........................................................................................................ 73 2.8.4 Volume Swell .............................................................................................................. 73 2.8.5 Shrinkage .................................................................................................................... 74 2.8.6 Tensile Strength Change ............................................................................................. 75 2.8.7 Elongation Change ...................................................................................................... 75 2.8.8 Work Function Modulus Change ................................................................................ 76
2.9 Seals ........................................................................................................................................ 76 2.9.1 Introduction ................................................................................................................ 76 2.9.2 Seal Types ................................................................................................................... 78
2.9.2.1 Static Seals ................................................................................................... 78 2.9.2.2 Dynamic Seals ............................................................................................. 81 2.9.2.3 Radial Lip Seals ........................................................................................... 91 2.9.2.4 Mechanical Face Seals .................................................................................95
