22-05-2012, 12:20 PM
BASICS OF HYDRAULICS
HYDRAULICS.ppt (Size: 614.5 KB / Downloads: 60)
1) DEFINITIONS
1.1) HYDRAULICS
1.2) CLASSIFICATION
1.2.1) HYDROSTATICS
1.2.2) HYDRODYNAMICS
1.3) FORCE , PRESSURE , AREA
1.4) PASCAL’S LAW
2) MULTIPLICATION OF FORCES
2.1) BRAMAH’S PRESS
2.2) LAW OF CONSERVATION OF ENERGY
3) HYDRAULIC POWER TRANSMISSION
3.1) LINEAR ACTUATOR
3.2) ROTARY ACTUATOR
PASCAL’S LAW
PRESSURE APPLIED ON A CONFINED FLUID IS TRANSMITTED UNDIMINISHED IN ALL DIRECTIONS AND ACTS WITH EQUAL FORCE ON EQUAL AREAS AND AT RIGHT ANGLES TO THEM.
ADVANTAGES OF HYDRAULICS
RELIEF VALVE PROTECTS THE SYSTEM BY MAINTAINING
THE SYSTEM SET PRESSURE.
ANY INCREASE IN PRESSURE IN SYSTEM IS RELEAVED
TO TANK . ( MOMENTARILY DIVERTING FLOW TO THE TANK. )
THUS OVERLOAD PROTECTION IS ACHIEVED.
PRINCIPLES OF FLOW
HOW FLOW IS MEASURED ?
VELOCITY
FLOW ( FLOW RATE )
FLOW RATE AND SPEED
FLOW AND PRESSURE DROP
LAMINAR AND TURBULENT FLOW
BERNOULLI’S PRINCIPLE
FLOW IS THE ACTION IN THE HYDRAULIC SYSTEM THAT GIVES THE ACTUATOR ITS MOTION.
PRESSURE GIVES THE ACTUATOR ITS FORCE , BUT FLOW IS ESSENTIAL TO CAUSE MOVEMENT.
FLOW IN THE HYDRAULIC SYSTEM IS CREATED BY THE PUMP
PRESSURE INDICATES WORK LOAD