SEALING MECHANISM
Sealing mechanism
The rubber seal is placed in the sealing groove with one or both sides of the fluid medium to be sealed. Whether it is due to the mechanical pressure of the surrounding mechanical structure or the pressure transmitted by the hydraulic fluid, the elastomer compensates for the gap by deformation (elastic or inelastic), forming a "zero gap", or blocking the flow of the fluid sealed by it. The elasticity of the rubber compensates for the manufacturing and fitting tolerances, and the elastic memory inside the material is an important condition for maintaining the seal.
Factors to consider when choosing an O-ring seal
01 / Working medium and working conditions
When selecting an O-ring material, compatibility with the working medium should be considered first. It is also necessary to consider the pressure, temperature, continuous working time, operating cycle and other working conditions at the sealing place. If it is used in rotating applications, the temperature rise caused by frictional heat must be considered. Different seal materials have different physical and chemical properties.
02 / Sealed form
According to the load type, it can be divided into static seal and dynamic seal; According to the sealing purpose, it can be divided into hole seal, shaft seal and rotary shaft seal; According to its installation form, it can be divided into radial installation and axial installation. For radial installation, for shaft seals, the deviation between the inner diameter of the O-ring and the diameter of the seal d2 should be as small as possible; For hole seals, the inner diameter should be equal to or slightly less than the diameter of the groove d1.
When installing axially, the pressure direction should be considered. Interior. force, the outer diameter of the O-ring should be about 1~2% larger than the outer diameter of the groove d3; When the external pressure is used, the inner diameter of the O-ring should be about 1~3% smaller than the inner diameter of the groove d4.