■ Koyo Oil Seals: Features ■ Koyo O-Rings: Features ■ Koyo Functional Products: Features ■ FEM Analysis >

This catalog lists Koyo oil seals and O-rings, including all items ofthe dimension series specified in ISO, JIS and JASO (Japanese Automobile Standards Organization) standards. This catalog is also based on knowledge gained from our supply record, experience, expertise, technologies, and research developments that Koyo has acquired in cooperation with customers since its foundation in 1964.A specialty of this new catalog is the comprehensive information, itoffers regarding the selection and handling of oil seals and O-rings.Energy-saving, environment-friendly considerations are in greatdemand,...

1. Lightweight, compact, and energy-saving 3. Low heat generation and long servicelife by highly self-lubricating rubber materials > Koyo oil seals offer high sealing performance, whilebeing compact with reduced seal width. They helpreduction of machine weight, size, and energy con- sumption. Based on extensive research and experimentation,Koyo has succeeded in developing seal rubber materi- als with high self-lubrication performance. These rub- ber materials show limited chemical changes such ashardening, softening and/or aging.These materials can offer long service life under hightemperature...

High sealing performance against water, oil, air, vari-ous gases and chemicals.

Koyo produces various functional products based onadvanced sealing technologies and sophisticated man-ufacturing expertise acquired through extensiveresearch and production.Koyo functional products are very effective in improv- ing machine performance, reducing weight, size, noiseand vibration.Consult Koyo if there is no product in this catalog thatexactly matches your requirements--Koyo can custom-design products. Center bearing unitsՕ Bearings molded with vibration isolating rubber Spark-plug tube gasketsՕ Plastic gear shafts Pulley units բ֠ Various functional products ■ Bonded piston seals...

■ Friction dampers for manual transmissions ■ Various boots for joints > Air cleaner jointsՕ Carburetor joints Sprocket wheelsՕ Muffler joints Plastic gear shaftsՕ Oil strainers Mesh gasketsՕ Ball-component clutch releases Vertical gaskets բ֠ Various functional products >

Koyo uses the non-linear finite element method toanalyze non-linear materials such as rubber, for whichaccurate analysis was difficult before. The companyhas been studying sealing-mechanism theories by thismethod in order to develop new products. The findings so far have been very useful for basicresearch as well as for rubber-component design.The FEM is our common design tool today, enablinghighly reliable analysis and evaluation, speeding upresearch and product development. > Under no load Under no loadUnder slant load (stress distribution diagram) Under load > Under no loadUnder load > Under...

1.1 Nomenclature and functions of seal components (1) Nomenclature of components Oil seals are designed in a variety of shapesaccording to the applications and substances to besealed.Fig. 1.1.1 shows a typical shape of seal and itscomponent nomenclature. Oil seals work to prevent leakage of lubricants suchas oil and operational media from inside and also toprevent the entry of dust and contaminants fromoutside. 8 > Back face 5 > Metal case Minor lipSealing edgeMain lip SpringNoseO.D surface 6 7 4 > 2 3 1 > Fig. 1.1.1 Typically shaped oil seal and component nomenclature (2) Component functions...

4 Spring The spring supplements the radial lip load at the sealingedge to ensure tight contact between sealing edge andshaft and enhanced sealing performance. The spring alsohinders the deterioration of main lip sealing performancecaused by high heat or others. Because this spring is a closely wound type coil, theinitial tension can be obtained high level, and thenchanges in load characteristics can be gradual withrespect to spring elongation. Radial lip load at the sealingedge can thus be kept stable at an appropriate level. > Spring load 5 Metal case The metal case provides rigidity on seal,...

Rubber O.D wall preventsleakage efficiently under pressure Nose gasket prevents leakagethrough the seal O.D Light metal casewith sufficient rigidity Lip design with excellent followability Linear contact type sealing edge with high durability under high-speed rotation Minor lip preventing entry of contaminants Rubber materials with high self lubricating property >

Seals are classified by O.D wall material, lip type andwhether with spring or without spring. Major oil sealsare specified in ISO 6194, JIS B 2402, and JASO F401. Table 1.3.1 shows common seal types.Table 1.3.2 lists the seal type codes used at Koyo,along with the corresponding codes used in the ISO,JIS, and JASO standards. > 1) With spring type secures stable sealingperformance2) the housing bore 4) Reinforcing inner metal case in the metalO.D wall type protects the main lip5) > Rubber O.D wall type provides stable sealingperformance around the seal O.D surface With minor lip type is applied...

Resin or light metal housing has large thermal expansion and is easily damaged. (3.2~1.6) mRa(1.6~0.4) HousingmaterialHousingdesign Split housing Roughness ofhousing boreRa, յ m Small thermal expansionand hard materialOne solid type AtmosphericpressureGrease orhigh viscosity oil mRa > O.D wall material Fluid like oil,waterPressure P <30 kPa S 5 m/s>== Shaft runout 0.1 mmTIR Housing bore > eccentricity 0.1 mmTIR = > Substance tobe sealed Shaft surface speed P , kPa S , m/sTotaleccentricity S <5 m/s Shaft runout < 0.1 mmTIRHousing bore eccentricity < 0.1 mmTIR P 30 kPa= > > Necessity of spring...

4) Shaft end chamferTo protect seals from damage at mounting ontoshafts, recommended chamfer on the shaft end isshown below. > 1) MaterialSteel or cast iron is generally used as the material ofhousings. When aluminum or plastic housing is used,the following consideration and study are required, as seal seating in housing bore may become loose fittingunder high temperature because the housing materialand seal material have different linear expansion coefficients. This may cause problems such asleakage through the seal O.D, or seal dislocation. 2) Dimensional accuracyThe housing bore tolerance...