Shaft Speed - Considering the speed that the shaft will be moving, the runout, the housing bore and the type of oil being sealed is vital to making sure you select an oil seal that will not suffer from abrasions or spiralling.
Figure 14.3. Oil aging of fluoroelastomers.5 Chart shows percent retained elongation. Conditions: Aged at 150°C in Service Fluid 105 (oil changed every 168 h).
Super Helix Seal

Maintenance and Inspection of Oil Seals
Vulcanizates of several fluoroelastomers, listed in Table 14.1, were exposed to a standard 5W-30 engine oil, ASTM Service Fluid 105, for up to 6 weeks at 150°C (302°F).5 The oil was changed weekly, but was not aerated. Retained elongation was measured after exposure for 1, 2, 3, and 6 weeks; data are shown in Fig. 14.3. The results indicate that bisphenol-cured FKM-A500 VDF/HFP copolymer, FKM-B600 VDF/HFP/TFE terpolymer, and peroxide-cured FEPM-7456 TFE/P/VDF terpolymer lost most of their original elongation over the course of the test exposure, indicating considerable additional cross-linking occurred by reaction with amine- and phenol-containing oil additives. The other fluoroelastomers showed better retention of elongation, being much less susceptible to additional crosslinking. Note that FEPM-7456 contains a high level of VDF (about 30%), while FEPM-7506 contains a relatively low VDF level (10–15%) to serve as cure site for bisphenol curing. The other FEPM types contain no VDF.

car engine gasket.
5. TYPES OF FLUID: Numerous oil seals can interact with oils, fuels, grease, water and more. However, know exactly what type of fluid the rotary shaft seal will be in contact with will ensure the longevity of the seal and the machinery.
Table 1: The order of priority for selecting oil seals
First, an elastomer, most often nitrile, is vulcanised to a metal ring. This creates a stiffening effect that includes a specialised metal tension spring directly behind the sealing lip, keeping the oil seal firmly in place against the moving part.
Our rubber seals are used in the following industries:
Gaskets and oil seals should be replaced if worn or leaking, or whenever removed during servicing. Replacement is simple, but some engine dismantling may be necessary to reach them. Buy gasket sets from a dealer for the make of car, and state clearly for what parts they are needed.
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