EXPERIMENT 8 INTRO

EXPERIMENT 8 : Basic Hydraulic circuit


1.0 LEARNING OUTCOMES:

At the end of this experiment, the student should be able to;

1.1 List down the main component in hydraulic system
1.2 Explain the function of each component

2.0 EQUIPMENT / APPARATUS

2.1 Hydraulic experiment set
2.2 Hydraulic pump
2.3 Directional control valve 4/2
2.4 Double acting cylinder

3.0 SAFETY AND HEALTH

4.0 THEORY

Hydraulic fluids are a large group of fluids used as the motive medium in hydraulic machinery. Fluid types include synthetic compounds, mineral oil, water, and water-based mixtures. The fluids are found in machinery and equipment ranging from brakes, power steering systems, and transmissions to backhoes, excavators, garbage trucks and industrial shredders. Hydraulic systems are very common in aircraft flight control systems
A hydraulic circuit is an interconnected set of components that convert pressurized liquid (usually oil) into mechanical work. The circuit comprises the following components:
• Active components
o Power pack
• Transmission lines
o Hydraulic hoses
• Passive components
o Hydraulic cylinders
Hydraulic cylinders get their power from pressurized hydraulic fluid, which is typically oil. The cylinder consists of a cylinder barrel, in which a piston connected to a piston rod is moving. The barrel is closed by the cylinder bottom and by the cylinder head where the piston rod comes out of the cylinder. The piston has sliding rings and seals. The piston divides the inside of the cylinder in two chambers, the bottom chamber and the piston rod side chamber. The hydraulic pressure acts on the piston to do linear work.
A hydraulic cylinder is the actuator or "motor" side of this system. The "generator" side of the hydraulic system is the hydraulic pump, that brings a fixed or regulated flow of oil into the system. Mounting brackets or clevisses are mounted to the cylinder bottom as well as the piston rod.