O-ring seals are widely used in various dynamic and static sealing applications due to their low manufacturing cost and convenient use.
Sealing mechanism of O-ring:

O-ring is an automatic bi-directional sealing component. During installation, the pre compression in both radial and axial directions endows the O-ring with its initial sealing ability. It increases with the increase of system pressure.
Factors to consider when choosing O-ring seals:

1. Sealing form
According to the type of load, it can be divided into static seal and dynamic seal; According to sealing purposes, it can be divided into hole seals, shaft seals, and rotary shaft seals; According to its installation form, it can be divided into radial installation and axial installation. When installing radially, for shaft seals, the deviation between the inner diameter of the O-ring and the sealed diameter d2 should be minimized as much as possible; For hole sealing, its inner diameter should be equal to or slightly smaller than the diameter d1 of the groove.

2. Working medium and working conditions
When selecting O-ring materials, the compatibility with the working medium should be considered first. It is also necessary to comprehensively consider the working conditions such as pressure, temperature, continuous working time, and operating cycle at the sealing point.