Hydraulics and Pneumatics

1. Hydraulics and Pneumatics

2. Pneumatics • Pneumatics – the study of pressure in gasses • A pneumatic system is a system in which a gas (like air) transmits a force exerted on the gas in enclosed space • In most pneumatic systems the air is then released Ex. Super Soaker Gun, Staple Guns and Nailers (with compressed air), pump up sports shoes, vacuum cleaner, hair dryer, drinking straw, natural gas pipeline, our respiratory system

3. Usually the air passes through a pneumatic device under pressure and then escapes outside the device • Air is drawn in from outside and compressed • Hoses carry the high-pressure air to the device • The compressed air will expand when released; this allows it to exert a great deal of force • The amount of pressure is controlled by the size of the opening • Remember P = F A • Test with exhaled air into hand

4. Hydraulics • Hydraulic systems use the force of liquid in a confined space • They are usually closed systems • Ex. Jaws of life, air plane systems, your circulatory system • Hydraulic systems rarely act alone; usually combined with gears, levers, pulleys and wheels and axles • Machines contain tanks filled with hydraulic fluids and pumps that generate pressure • Energy is supplied by gasoline engine or electric motor • Valves direct high pressure fluid through pipes to the parts of the machine where the pressure of the fluid is needed to generate large forces or to dig See the examples in the textbook p.320