52) Which device is used for handling and removing contamination from hydraulic oil?

53) Which part of double acting cylinder prevents air leakage from cylinder to atmosphere?

54) What is the defect caused by inter locked air bubbles and pockets in the hydraulic pipe lines and components?

55) What is the cause for oil flow under pressure while passing through the restricted passage?

56) Which valve prevents the system pressure from rising too high if the pressure regulating valve fails?