2023-11-28
Measures To Reduce Failure Rate Of Hydraulic Cylinder
Seal dimensions during installation: Before installation, the seal has four dimensions to consider: the inner diameter of the seal's root, the outer diameter of the seal's root, the inner diameter of the lip, and the outer diameter of the lip.
Seal dimensions when installed and not in operation: When the seal is installed in the groove but has not yet been subjected to working conditions, the groove size remains unchanged. However, the dimensions of the seal change. The outer diameter of the seal's root becomes the same as the outer diameter of the groove, while the diameter of the inner lip matches the diameter of the piston rod. The inner diameter of the seal's root is determined by the clearance between the seal and the piston rod plus the diameter of the piston rod.
Seal behavior during operation and pressurization: When the hydraulic cylinder starts working and is pressurized, the seal's inner and outer lips come into contact with the inner and outer walls and move slightly backward. The seal's root is squeezed backward due to the pressure. As the pressure increases, the force of the hydraulic oil on the seal also increases, causing increased overall deformation of the seal.
Seal behavior during depressurization: After completing a working cycle and depressurizing the cylinder, the seal returns to its original state. It undergoes repeated deformation and restoration during operation. The seal remains undamaged until the volume of the seal's lips is significantly reduced.
Matching groove size tolerance with the seal: The tolerance of the hydraulic cylinder groove size needs to be appropriately matched with the seal. Different types of reciprocating seals, such as L-shaped, U-shaped, V-shaped, or Y-shaped lip seals, are commonly used in hydraulic systems. The lip-shaped pressure surface of these seals creates a sealing effect by making slight contact with the sealing surface. The sealing performance increases with higher pressure as the contact force and area between the seal and the sealing surface increase. Conversely, as the pressure decreases during cylinder return, the contact area and force decrease, leading to reduced sealing performance.
By understanding these seal states and ensuring proper matching between the seal and the groove, it is possible to enhance the reliability and longevity of hydraulic cylinders. Regular inspection, maintenance, and replacement of seals when necessary are also essential for optimal performance.