Maintaining the system's tightness is a prerequisite for ensuring system operation. Therefore, it is necessary to always ensure that the sealing device has good sealing performance under the working pressure of the system and the temperature range that may be encountered.
Type of sealing device
Depending on the operating conditions, the seals used in hydraulic and air-conditioning systems can generally be divided into two types of seals: one for dynamic seals and one for static seals. A relative movement between the two elements being sealed is called a dynamic seal. Such as the cylinder of the hydraulic actuator, the end cover and the piston, the seal between the output rods, and the like. The dynamic sealing device is further divided into a rotary seal and a sliding seal. The former is the relative rotation of the two components being sealed, such as the output shaft of the oil pump and the hydraulic motor, and the latter is the relative sliding of the two components sealed. The two elements that are sealed are not moved relative to each other, and the sealing device is called a static seal. Such as the fixed joints in the hydraulic system and air-conditioning system accessories. This type of sealing device is sealed by the pressing action when the sealing faces are joined.
From the form of the sealing device, the frequently used rubber ring can be classified into an "O'-shaped sealing seal, a "V"-shaped sealing ring, and the like.
Basic requirements for seals:
1 has a tight and reliable sealing performance within a certain pressure and temperature range.
2 long-lasting wear resistance.
3The frictional resistance is small and the friction factor is stable.
4 wear speed is slow, and can automatically compensate to a certain extent.
5 has reliable impact resistance.
6 The structure is simple, compact, convenient for loading and unloading, and low in cost.
7 It is convenient to manufacture and maintain, and has a long service life. It should ensure interchangeability and standardization.
The mechanism or component containing the sealing element is called a sealing device.
The basic requirements of the sealing device: the sealing device requires compact structure, reliable performance, convenient manufacturing and maintenance, and low cost.