Hydraulic Seal is an agent, which prevents leakage of oil from the hydraulic elements and protects the systems from dust/dirt. The major function of the seal is to maintain pressure, prevent loss of fluid from the system and to keep out contamination in the system to enhance the working life and functional reliability over a longer period. The bottom of the drill hole provides the hydraulic seals, by the beginning of a layer of low-permeability backfilling material or by hydraulic packers. The hydraulic seal is another effective method of sealing the oil into a compartment within the gas turbine. The hydraulic seal relies on a trough to be filled with oil, the seal fins on the opposing component are dipped into the oil and thus create the seal. Hydraulic seals are used on low-speed areas of the engine.