According to the technical requirements of hydraulic cylinders, seals must also be produced according to the technical requirements of the cylinders. Li Gong mainly analyzes the oil cylinder seals under the following two pressures.

1、 If the pressure of the oil cylinder is required to be above 25MPa, the speed is 0-0.5 meters/second, and the oil temperature is 80 ℃, the sealing element must meet the following technical requirements:

The hardness of the sealing element should be selected between 92 degrees and 97 degrees. As the cylinder pressure increases, the hardness of the selected sealing element should increase.

The linear speed of the sealing lip must reach 0.5 meters per second.

Seals should withstand temperatures ranging from -30 ℃ to 110 ℃. Due to the fact that the temperature of the lip contact surface of the sealing element is higher than the temperature of the hydraulic oil, the selected sealing element must be able to withstand high temperatures up to 110 ℃; In some areas, the temperature may be around -30 ℃, so the selection of sealing components should also be able to withstand low temperatures as low as -30 ℃.

Special seals should be selected, for example, shaft seals need to be used for shaft seals, piston seals need to be used for piston seals, and dual purpose seals for shaft and piston cannot be selected. Because the root width of the dual purpose seal is smaller than that of the dedicated seal. Under high pressure, the root deformation of the dual purpose seal is relatively large, while the specialized seal has a wider root under the same pressure and less compression deformation, reducing the possibility of being squeezed out by the piston rod.

A gasket needs to be added to the root of the seal. In order to prevent damage to the root of the sealing element due to extrusion and pulling, adding washers when the cylinder pressure exceeds 25MPa can reduce the deformation of the sealing element and the possibility of friction with the piston rod or the inner wall of the cylinder block. The hardness of the gasket is directly proportional to the pressure, and the greater the pressure, the greater the hardness.

2、 If the pressure of the oil cylinder is required to be below 25MPa, the speed is 0.5 meters/second, and the oil temperature is 80 ℃, the sealing element needs to meet the following requirements:

The hardness of the seal should be between 85 degrees and 92 degrees, as the lower the hardness, the better the elasticity of the seal.

The requirements for speed and temperature are the same as when the pressure exceeds 25MPa.

You can choose various forms of seals, such as specialized seals and dual purpose seals.