①The shaft speed ratio is due to the design scheme and structure. High-speed oil seals should be used for high-speed shafts, and low-speed oil seals should be used for low-speed shafts. Low-speed oil seals cannot be used on high-speed shafts. it is good.

②When the working temperature is high, the application temperature should be polypropylene or silicone, silicone, silicone glue. And should find ways to reduce the water temperature in the car's fuel tank. When the application temperature is too low, low temperature resistant vulcanized rubber should be used.

③The oil seal with normal working pressure has poor bearing capacity, and the oil seal will deform when the working pressure is too high. Under the application standard of excessive working pressure, the compression support ring or the lifted compression oil seal should be selected.

④ When the installed axial force level oil seal and the shaft cooperate with each other, if the axial force is too large, its airtightness will decrease, especially when the shaft speed ratio is high. If the axial force is too large, an oil seal with a "W" cross section can be used.

⑤ The smoothness of the shaft's surface immediately endangers the life of the oil seal, that is, if the smoothness of the shaft is high, the life of the oil seal will occur.

⑥ Note that a certain amount of grease is required on the lip of the oil seal.

⑦Pay attention to avoid dust from penetrating into the oil seal.

1 Internal skeleton oil seal

The oil seal is widely used, but it is not in the aspects of *precision positioning* accuracy, parallelism, and framework heat rejection.

If the lip seal ring of the rotating shaft of the skeleton is exposed. The oil seal structure has two types: with or without auxiliary lip (type B) and with auxiliary lip (type FB). It wraps the good metal material skeleton of the stamping die in the vulcanized rubber to become the inner skeleton oil seal. The manufacturing process is more complicated, but the bending rigidity is good, it is easy to install, and the raw material of thick steel plate is not high.

2 The skeleton oil seal is exposed

There are two types of oil seal structure with or without auxiliary lip (W type) and with auxiliary lip (FW type).

The oil seal has precise positioning, high parallelism, convenient installation, and good heat dissipation of the framework. A part of the vulcanized rubber and the metal material skeleton can be produced and processed separately, and then glued together to become an exposed skeleton type. It is easy to produce and manufacture, and it has a low grid. This type of structure is often used between the United States and Japan.

3Assembled building skeleton oil seal

There are two types of oil seals with or without auxiliary lip (Z type) and with auxiliary lip (FZ type).

The oil seal is suitable for installation on the rotating shaft end of large and medium-sized, high-density machinery and equipment. Under the standard that the pressure difference does not exceed 0.3MPa, it has a sealing effect on liquid and lubricating grease. It assembles the vulcanized rubber lips, the metal frame and the spring ring to form an oil seal. It has internal and external skeletons to hold the vulcanized rubber lips. Generally there is also a partition to prevent the yellow bullet from slipping off.

Since the skeleton oil seal has an oil film operated by the knife edge of the oil seal between the oil seal and the shaft, the oil film has the characteristics of liquid lubrication. Under the effect of the liquid interfacial tension, the bending stiffness of the oil film just makes the oil film and the gas contact end produce a round surface, avoiding the leakage of the material during work, and completing the sealing of the rotating shaft. The sealing ability of the oil seal lies in the thickness of the oil film on the raised surface. If the thickness is too large, the oil seal will leak; if the thickness is too small, it is likely to cause dry friction and cause damage to the oil seal and shaft; there is no oil film between the sealing lip and the shaft, which is easy Hot and damaged.