In order to ensure that the hydraulic cylinder will not leak oil under any working state, its sealing work is particularly important, let's tell you what are the seals of the hydraulic cylinder? The seals used for hydraulic cylinders are composed of O-rings, part hole seals, roller seals, wiper rings and other components. The following hydraulic pump manufacturers will introduce in detail what the function of each different seal is.
First of all, O-shaped static sealing ring, can withstand the working pressure of more than 20MPa, in order to improve its performance will generally be used with PTFE material retaining ring.
Secondly, the part hole seal, according to its different use objects, is divided into V-shaped hole seal, U-shaped hole seal, Gray hole seal, combined hole seal. V-shaped hole seal is mainly used for heavy-duty hydraulic cylinders, which are installed back-to-back, and the guide element is copper sleeve; U-shaped hole sealing project and oil cylinder used in water conservancy, closed groove installation, guide element as guide belt; Glekong seals are generally used for servo cylinders with low internal leakage requirements; Combination bore seals are generally used for cylinders with a very compact internal structure, which do not need to be additionally added during use due to their own guide elements.
Moreover, roller seals are also divided into V-shaped shaft seals, U-shaped shaft seals, and St shaft seals. St shaft seals are generally used for the main seal in the piston rod sealing system in the cylinder, but because of their certain oil return, they need to be used with other seal combinations. The U-shaped shaft seal can be used alone below 20MPa working pressure, while above 20MPa working pressure it is necessary to add a retaining ring.
Dust rings are generally divided into double-acting dust rings and single-acting dust rings, which should be selected according to the shaft seal and working environment.
Finally, the best combination of piston rod seals of common hydraulic cylinders is Sterseal + U-shaped hole seal + single-acting wiper, V-shaped hole seal + wiper, double Sterseal + double-acting wiper.
