Hydraulics and Pneumatics Overview

Hydraulics and Pneumatics

• Hydraulics is a technology using engineering, chemistry, and other sciences to work with liquid properties, specifically how liquids produce motion. Modern hydraulics uses confined liquid to transmit power, multiply force, and create motion.
• Pneumatic systems use compressed inert gases for power, often compressed air, to power cylinders, actuators, etc.
• Hydraulic systems use fluid (often oil) to perform work.
• Pascal's Law states that pressure applied to a confined fluid is transmitted equally in all directions with equal force on equal areas. This is fundamental to hydraulic systems using a smaller piston to generate a larger force on a larger piston.

Hydraulics and Pneumatics Component Systems

• Fluid: Oil for hydraulic systems, air for pneumatic systems.
• Reservoir: Storage tank for the fluid
• Hydraulic pump (compressor in pneumatics): Converts mechanical energy into hydraulic (or pneumatic) energy, forcing the fluid into the system.
• Fluid lines: Transport fluid through the system.
• Valves: Control pressure, direction, and flow rate of the fluid.
• Actuator: Converts hydraulic energy into mechanical energy for work.

Applications of Hydraulic Systems

• Industrial: Plastic processing, steel making, automated production lines, and more.
• Mobile: Tractors, irrigation systems, construction equipment.
• Automotive: Brakes, shocks, steering, etc.
• Marine: Vessels, fishing boats, and naval equipment.
• Aerospace: Aircraft control, landing gear, and other systems.

Control Valves

• Control valves regulate flow, pressure, and direction.
• Pressure control valves: Reduce pressure in systems or pipes.
• Flow control valves: Control the rate of fluid flow.
• Directional control valves: Control the direction of fluid flow.

Check Valves

• Allow fluid flow in one direction only.

Thermocouples

• Electrical devices made from dissimilar conductors which create a voltage that changes with temperature.
• Used for temperature sensing across a wide range of temperatures.
• Employ the Seebeck effect, where a voltage is produced whenever two dissimilar metals are joined together and a temperature difference exists between the junctions.
• Types of thermocouples: J, K, T, N, E, etc. each with specific properties (e.g., operating temperature range).

Transducers

• Often, electric or electronic devices that convert one form of energy to another.
• Many devices that collect data from sensors, measuring temperature, pressure, sound.