- Seals can be divided into two categories: dynamic seals and static seals, according to whether there is relative movement between the surfaces of the seals. At present, the commonly used seals are named after the cross-sectional shape, including O-shaped, Y-shaped, YX-shaped, V-shaped and combined seals;
- The transverse surface of the O-ring seal is circular, which can be used as a seal for various fluids such as oil, water, and gas. There are two types of static seals and dynamic seals;
- The cross section of the Y-shaped seal is similar to the English letter Y, and it can be used for sealing by directly installing it into the groove without a support ring. It is mostly used for dynamic seals at hydraulic cylinders and piston rods;
- The structural characteristics of YX-shaped seals are small cross-section, simple structure, and the length-width ratio of the cross-section is more than 2 times, so the seal will not roll over in the groove, generally can only work for a long time below 80 degrees Celsius, and there are shafts and holes in two forms;
- V-shaped seals are generally made of fabric rubber or polytetrafluoroethylene pressed by multiple layers of rubberized fabrics, and are mostly used for dynamic sealing between the end cover and the piston rod in the hydraulic cylinder.