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[email protected] Тел. (495)-228-06-21, факс (495) 223-3071 1.8 Causes of seal failures and countermeasures
Table 1.8.2 Causes of seal failures and countermeasures (2) Oil leakage from lip (2) Symptom Heavy wear on lip
Lip uneven wear
Phenomenon
Causes
Countermeasures
Rough face, Streaks
1) Poor lubrication 2) Rough shaft surface finish 3) Entry of foreign materials
• Take pre-lubrication on lip • Improve lubrication • Improve shaft surface finish (See page 19.) • Attach prevention device for foreign materials
Hardening, Cracks
Excess heat generation due to 1) Poor lubrication 2) Excess shaft surface speed 3) Excessive inside pressure
• Improve lubrication • Examine cause of heat source • Change rubber to heat proof rubber (See Table 1.4.2 on page 16.) • Apply high pressure proof seal or breather (vent)
Dents
• Excessive inside pressure
• Apply high pressure proof seal or breather (vent)
Wear track width is uneven. Max. wear positions of main lip and minor lip are same.
• Center offset between shaft and housing
• Examine misalignment for shaft to housing (Take countermeasure to reduce offset)
Inclined seal was mounted into housing 1) Improper housing bore diameter, bore chamfer, corner radius 2) Improper mounting tool
• Correct housing bore; diameter, chamfer, corner radius based on pages 19 and 20 • Improve mounting tool (Consult Koyo.)
Uneven wear Wear track width is uneven. Max. and Min. wear areas are located 180˚ apart. (Main and minor lips show opposite pattern.)
Uneven wear
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