The objective problems of hydraulic and pneumatic sealing technology
With the continuous development and improvement of hydraulic and pneumatic technology, the development process of sealing technology is also constantly advancing. There are two main types of piston sealing technologies commonly used for a long time:
The first type is to squeeze the corresponding part of the sealing element through a certain pressure with the help of some media with a transmission effect. In this way, the corresponding radial force is generated to make the sealing effect extremely good. The sealing technology usually applies Yx type sealing ring. Since the lip seal is squeezed with the help of the corresponding transmission medium, the lip needs to be opened in the direction of the medium pressure, and the pressure on the corresponding lip will also be affected by the increase in the pressure of the transmission medium. Pressure, which makes the lip easier to wear, is also one of the factors that cause damage to the cylinder wall, and cannot guarantee its sealing effect. This is the main problem of this type of technology, which affects the service life of the sealing device.
The second type requires the use of a rubber sealing ring to generate radial pressure through the elastic deformation of the sealing ring to achieve the sealing effect. This type of piston sealing technology generally forms a composite sealing ring with an O-ring and a related elastic carrier.
Its sealing principle is mainly that the corresponding pre-tightening force is applied to the sealing ring during the movement of the piston to cause the composite sealing ring to undergo elastic deformation, and then to generate radial force to promote the composite sealing ring and the cylinder Close to the wall to effectively achieve the sealing effect. In the process of using rubber sealing rings for sealing, the corresponding pre-tightening force is relatively large, which will cause the corresponding O-rings to have a lot of wear. This type of sealing technology is currently the most commonly used sealing technology. However, even if this composite sealing technology is applied, there will be many problems. For example, the sealing ring will produce elastic deformation in this composite component, which may cause the elasticity of the rubber ring to be greatly reduced, and the rubber ring Ageing. In addition, the zero-grade rubber ring is a solid structure. During the specific operation of the relevant transmission device, a lot of heat will be generated and accumulated in the sealing ring due to the frictional force therein. The heat is difficult to dissipate in time, making The aging speed of the rubber ring is further increased, and the service life of the corresponding sealing device is getting lower and lower.
In the past, the more traditional hydraulic-pneumatic sealing technology required the help of some media that can push the piston to run, which would be subjected to extremely large radial...