Oil seal is through the control lips mouth and cooperation between the surface over surplus quantity, and the static and dynamic conditions in all can play the role of stop leak, and at the same time must meet the following conditions:

1, according to standards of tolerance manufacturing oil seal.
 
2, the surface of shaft requirements, such as the shaft roundness, beating quantity, impact load and deformation of the sex to control the dynamic limits, so as to establish and maintain the satisfaction of the oil film.

2.1 shaft surface roughness
Sealing ring is action, shaft surface roughness is a major factor, (Ra = 0.2 ~ 0.8 υ m or Rz = 1 ~ 4 υ m, Rmax = 6.3 υ m) work in order to preserve the oil film Ra and Rz value above are generally not less than the minimum value parentheses, in order to guarantee service life, Ra and the value of the Rz should not be greater than the maximum, roughness more than Rmax can also lead to leak.

2.2 the hardness of shaft
And oil seal contact parts of the shaft minimum hardness is commonly RC30 surface. In the installation process easier to scratch shaft occasions, suggest the hardness of shaft increased to RC45 at least, in case the shaft in installation is permanently damage, affect the sealing ring sealing effectiveness.

2.3 eccentric
Eccentric can lead to irregular wear, influence the seal life; According to the practical experience of effective, eccentric amount should be held in 0.25 mmTIR below.

2.4 the bump or not round shaft
This kind of situation is caused by mechanical installation, if use bolt connection the axis of the flywheel will take place when this kind of phenomenon, it will lead to seal leakage.

2.5 the radial shaft a momentum
Generally no more than 0.25 mmTIR, or in the shaft speed increase, oil seal labial ministry cannot follow the axis of the high frequency partial convex function, and lead to seal failure; At the same time in the higher rotating speed, the rubber lips because of its inertia have left the possibility of shaft surface, also lead to seal failure; When the Lord lip and axis of the radial run-out deviation between than to maintain fluid dynamic lubrication must the value, in the position of the sealed the fluid will leak, has no seal effect, produce leakage phenomenon.
 
3, and the choice of rubber lips materials in use of the environment conditions can play a role.

3.1 lubricating oil
Oil use process, not only the material itself will change, and lubrication of the additive will also be changing, in the change will produce heat, after decomposition oxide, these decomposition products to seal the material will may produce very big effect, so also tries to consider.

3.2 temperature
Time and temperature can make the seal material and lubricating oil and their respective itself of action between happen irreversible changes. In the low temperature, rubber material temporarily harden, lubricant viscosity temporarily increase, and the Lord lip may leakage occurs, sealing ring produce split and abnormal wear, material of such hardening phenomenon can lead to Lord lips mouth ability to change with shaft, and low leakage occurred. In the continuous high temperature entity may be hardened rubber phenomenon. Axis over surplus quantity and pressure on oil seal role will also make rubber lip and shaft face resulting heat phenomenon, high rotation speed, pressure can also lead to the Lord labial ministry temperature, and make contact and formed between lubricant labial ministry large temperature difference, so as to make lips mouth below lubricant viscosity change, also can affect sealing ring sealing effectiveness.

4 properly installed oil seal

4.1 tilt installation
Oil seal Lord lip can effectively on whether sealing function of a factor is outside its end face of reference axis perpendicular installation. The outer diameter measuring along the oil seal verticality take 0.25 mmTIR is recognized to be effective.
4.2 the sealing lip protection
Oil seal lips mouth will slip through all of the surface should be smooth, without rough point, installation process lips mouth don't flip, before the installation of the shafts or oil seal lips mouth oil-can film or grease film, in order to prevent the damage the oil seal lips mouth of possibilities.

4.3 adhesive strength
Sealing material and the metal embedded with a bad will also serious lead to seal failure.
 
5 be mistaken for oil seal leakage examples are:
By taking 5.1 machine leakage. Gaskets of permanent deformation, tighten the screws to loosen, the assembly parts deficiencies.

5.2 the body, cover by machine parts such as the cracked concave nest (casting) place leakage.
5.3 the oil seal and assembling cavities face toward the atmosphere of oil are attached.
Use of the early 5.4 oil seal lubricants overflow.




Other News:
Skeleton oil seal leakage related factors
Bearing heat treatment technology development and application effect
Steel losses of 33% transfer to the Midwest demand
Steel price good policy into uplink channel will come soon
The rolling bearing manufacturing-collar is forming
INA bearing installed and remove skills analysis
China steel excess capacity scale or continued to escalate
Domestic steel price movements are not have reversed conditions