/gases or will let into the atmosphere in case of air Seals: These prevent the leakage of fluid into the atmosphere or surroundings Filter, Lubricator and Regulator Circuit (FRL UNIT):These circuit are used to remove dirt present in the fluid. They will also lubricate and regulate the flow of fluid Accumulator: These are used to produce head which can be converted into useful work Cylinders Cylinders are primary type of actuators used in fluid circuit. The cylinder used in fluid circuit will consist the following parts Cylinder barrel Piston Ports Piston rod Cylinder Head Valves Seals Whenever fluid is supplied to the cylinder the piston will move. This movement of piston is called as stroke. The piston can move in forward or reverse direction. The cylinders can be classified as double acting or single acting. In single acting cylinder work will be performed only in the forward stroke. The fluid will be supplied to the cylinder only during the forward stroke. The return stroke is achieved by the spring mounted in the cylinder. In double acting cylinder there will be two ports for the supply of fluid. Work can be obtained both at forward and reverse strokes. Directional control valves required for the easy operation of double acting cylinder. Advantages of using Fluid Power The transmission of power through fluid has following advantages compared to the other modes Power transmission requires fewer mechanical parts. The problem of breakage of parts like gears, cams, belts and chains is not involved. Lesser noise and less vibration can be ensured from the system by proper installation of fluid system Forces can be conveyed up and down with less loss in efficiency System overloading can be prevented by use of automatic relief valves Economical compared to other modes Use of fluid power The hydraulic press, invented by Englishman John Brahmah, was one of the first workable pieces of machinery developed that used hydraulics in its operation. Today, hydraulic power is used to operate many different tools and mechanisms. some of the devices which uses hydraulic power are Hydraulic jack Hydraulic doorstops Hydraulic brakes Power steering Tractors Various construction vehicles and equipment Some devices which uses Pneumatics are Pneumatic drillers used in mining Air motors Difference between Hydraulics and Pneumatics Precise control of velocity is achievable in hydraulics while due to compressible nature of gas, Pneumatics cannot have precise control over velocity. In Hydraulics, self-regulation