BS
Entry of dust and debris is one of the most common reasons oil seals fail. For instance, in high-pressure applications, even the smallest sediments can create a gap in the seal, causing the oil to leak and dirt to get in.
JTEKT
Notes
1) ISO: International Organization for Standardization
2) 2) JIS: Japanese Industrial Standard
Purpose of an Oil Seal
OIL SEAL
Most oil seals consist of some basic elements that configure their structure, such as the sealing element, the metal case, and the spring:
7. Repeat the Process
Oil or other seals can be used for grease and oil seals. A flexible lip, radial lip, or rotating shaft seal are different names for an oil seal. Single lip, double lip, triple lip, and four or more lips are frequent configurations. Double dust lip seal A seal with a garter spring design is the Double Dust Lip (DDL) seal. It has two dust lips, as the name would imply, plus a fluid lip with a garter spring to keep the lip firmly attached to the wear ring. Given the ongoing evolution of bearing seal designs, this seal would be considered a starting seal. For more than 50 years, this design has been the workhorse of the freight business; it still is in some regions. NBC Brenco Bearing Seal performs the fundamental task of keeping contaminants and grease out. Because of the garter spring, this seal would add the most torque and temperature to the bearing. Efficiency plus bearing seals Due to eliminating the fluid lip using poly inserts and rotors, the Efficiency Plus (EP) seal has a reduced torque value of fewer than 15 in-lbs. Although it features a triple dust lip rather than a double dust lip, the dust lip is still a molded component of the design. A labyrinth-like insert and rotor interlock each other to replace the fluid lip. NBC Brenco labyrinth provides excellent grease while lowering the torque required to rotate the seal. Other types of oil seal and grease seals include:

wheel oil seal. Signs of a faulty wheel oil seal include oil leakage from the wheel hub, unusual noise coming from the wheel assembly, and excessive play or wobbling of the wheel. If any of these symptoms are noticed, it is important to have the wheel oil seals replaced immediately to prevent further damage to the wheel bearings.
Common Mistakes to Avoid
Material Code ISO 1629
Figure 5 explains the JTEKT seal numbering system.
Seal numbers consist of
(1) the seal type code,
(2) the spring code,
(3) the lip type code,
(4) the dimensional numbers, and
(5) the special type code,
and Table 6 shows examples of each of these codes/numbers.