What is the effect of O-ring compound hardness on friction?

O-ring is a kind of sealing product with simple shape and structure, various specifications and a large number of users.

The sealing quality life of the O-ring depends on the dimensional accuracy and the compound. It is generally required that the rubber compound has a certain mechanical strength, tear resistance, excellent heat resistance, oil resistance, chemical resistance, and small compression and long-term deformation under application conditions, which are its primary indicators.

O-rings are used in various pipelines, and conflicts will inevitably occur during transportation. So what impact will the conflicts bring to the O-rings?

 
In sealing arrangements, the collision can damage the worn O-rings and affect the sealing. The degree of wear mainly depends on the size of the static conflict. When the liquid pressure is small, the conflict scale of the O-ring depends on its compressive shrinkage. When the working fluid is under pressure, as the pressure of the delivery pipeline increases, the conflicting force increases. When the working pressure is less than 20MPa, the approximate linear relationship. When the pressure is greater than 20MPa, the pressure effect, the addition of the O-ring and the metal contact area gradually slows down, and the conflict force will increase accordingly.
When the working pressure is high, the way to add the hardness of the O-ring compound is to add the filling amount of carbon black, but the filling amount is too high, the mixing is difficult, and the basic physical properties of the vulcanizate are damaged, and the compound is prone to scorch.

Under normal circumstances, the service life of the O-ring is increased with the increase of hydraulic pressure, and the pressure of the conveying pipeline is strictly controlled. The addition of collisions during the installation results in high collision heat between the rotation of the installation and the O-rings. Because most O-rings are made of rubber materials, they have poor thermal conductivity. Thus, conflict heat can cause the rubber to degrade, resulting in the loss of the O-ring seal. Conflicts can also cause damage to the O-ring surface, reducing the amount of compression. Severe collisions can damage the O-ring's appearance, and loss of the seal can affect the safety of the pipe. So the conflict will seriously affect the O-ring seal.

O-rings are suitable for all kinds of mechanical equipment, in the specified temperature, pressure and different liquid and gas medium, in static or moving state of the sealing effect. In machine tools, ships, cars, aerospace equipment, metallurgical machinery, chemical machinery, construction machinery, construction machinery, mining machinery, petroleum machinery, plastic machinery, agricultural machinery and other instruments, a large number of various types of seal components are used . O-rings are primarily used for static and reciprocating seals. For rotary motion seals, only low speed rotary seals are available. O-rings are generally installed on seals of rectangular cross-section on the outer or inner ring. O-rings still perform excellent sealing and shock absorption in environments such as oil, acid, grinding, and chemical corrosion. Therefore, O-rings are used for more widely sealed hydraulic and pneumatic transmission systems.

The O-ring has its own sealing effect and does not need to be adjusted periodically. When it is used for sliding sealing, the sealing function can not be affected by the direction of movement. It is small in size and easy to use. Because the sealing ring has a large adaptability, the scale of use It is very wide, but it is easy to deform when the pressure peak reaches a certain pressure, and it is possible to squeeze out the gap. It is widely used in aviation and hydraulic engineering.