- A thin rubber gasket may seem like a small and insignificant part, but it plays a crucial role in various industries and applications. Whether it's used in automotive, plumbing, electronics, or machinery, a thin rubber gasket serves as a seal to prevent leakage, contamination, and to ensure the proper functioning of equipment.
Fit the new gasket to the cover or head — whichever the old gasket was fixed to.
No single physical property of rubbers is responsible for the successful performance of an oil seal or ‘O’ ring. The ultimate tensile strength, breaking elongation, modulus, shore hardness, creep and stress relaxation in tension and compression loads are all important physical properties that characterize a seal or ‘O’ ring. Compression strength and set together with stress relaxation or decay are important for effective sealing. The difference in these properties in a swollen seal is highly critical. An optimum swelling value in a fluid medium is a desirable feature. De-swelling decreases the seal pressure against the wall of the housing where the seal is fixed, leading to leakage. Over swelling minimizes the physical properties of the rubber. Seals made of polysulfide rubbers have extreme fuel resistance but undesirably high compression set. The effect of temperature on the seal is an important factor. Swelling under stress can increase at higher temperatures and a suitable compounding technique should be adopted to reduce this effect.
The proper functioning of seal oil pan, oil seal turbo, and oil gasket seal is crucial for the performance and longevity of the engine. High-quality seals are essential to prevent oil leaks, maintain proper lubrication, and protect the engine components from wear and damage. When selecting these seals, it is important to prioritize quality, durability, and compatibility with specific engine models to ensure optimal performance and reliability.
Operating temperatures for engine oil seals (see Fig. 14.11 and cross-section of lip seal with garter spring in Fig. 14.22) vary widely, depending on engine design and location within the engine. Typically, the rear crankshaft seal is subjected to much higher temperatures than the front seal. Oil sump temperatures vary considerably, depending on provisions for oil cooling. This allows use of hydrogenated nitrile (HNBR), silicone, or acrylic elastomers for some seals in relatively low-temperature environments (120–140°C or 250–284°F). Standard fluoroelastomers (FKM), bisphenol-cured VDF/HFP/TFE terpolymers with 68–69% fluorine content, perform well in oil service up to about 160°C (320°F). More resistant fluoroelastomers are necessary for reliable long-term performance in more severe environments.
The metal case and spring material used in the oil seal should be selected based on the substance to be sealed.
Table 6 shows how to select the metal case and spring materials.