O -type seal is a typical squeezing seal. The compression ratio and tension of the diameter of the O -type cross section are the main content of the sealing design, which is very important for sealing performance and service life. The O -type circle is usually installed in the seal tank for sealing.
The good sealing effect of the O -type circle seal depends to a large extent on the correct matching of the size of the O -type circle and the size of the groove. The proper compression and elongation of the O -type circle forms the sealing. When designing and processing the sealing device, the compression of the O -type circle is too small, leakage, too much compression, and the rubber stress of the O -type circle is relaxed and leakage will occur. Similarly, excessive stretching of O -type circles during work will accelerate aging and cause leakage.
The design principle of the O -type sealing part has three elements:
1. Compression rate; 2. expansion and contraction; 3. contact width;
Three factors need to be considered when choosing the O -shaped circle compression ratio:
1. Need enough sealing contact area.
2. The friction force is as small as possible.
3. Try to avoid permanent deformation.
O -sealing scalability:
After installing the O -type circle in the sealing slot, there are usually some stretching. Different from compression, elongation has a significant impact on the sealing performance and service life of the O -shaped circle. If the elongation rate is large, not only the O -type circle is difficult to install, but due to the changes in the diameter of the section, the compression ratio will be reduced, resulting in leakage.
The exposure width of the O -type circle seal:
After installing the O -shaped ring to the sealing slot, the cross section is compressed and deformed. The deformation width and the contact width of the shaft are related to the sealing performance and service life of the O -shaped sealing ring. If the value is too small, it will affect the sealing performance, and if it is too large, friction will occur. Creating friction heat and affecting the O -ring seal.