Classification of ACTUATORS

Q.1 Classify hydraulic actuators in brief.

Hydraulic actuators also called consumers, are the elements of hydraulic system, which transform the hydraulic energy into useful work. Hydraulics in its applications is generally concerned with, moving gripping, lifting and rotating motions with force. Devices that actually achieve thisobjective are called actuators. Depending upon the motion they transmit, the actuators are classified as,

a) Linear actuators

 Linear actuators convert hydraulic energy into straight-line motion.They include various types of hydraulic cylinders.
b) Rotary actuators

 Rotary actuators convert the hydraulic energy into rotational motion. They may further divided as limited rotation actuators and hydraulic motors. Limited rotary actuators transmit a part of full rotation, where as the hydraulic motors are the hydraulic equivalent of electric motors, which may be unidirectional or bi-directional.

Q.2.Classify hydraulic Cylinders.

Ans : The various designs of hydrauliccylinder covers such a wide range that it would be beyond the scope of this book to describe all of them. Broadly, they are classified as below,

Q.3.Classify air (Pneumatic) Cylinders.

Ans:Air cylinder are classified as
follows

a) Classification based on cylinder
functioning

 1. Single acting  cylinders

 2. Diaphragm cylinder.

 3.Rolling diaphragm cylinders

 4. Double acting cylinders

 5. Tandem cylinders

 6. Rotary type cylinder.

b) Classification based on cylinder
movement

 1. Rotating cylinder

 2.Non rotating cylinder

c) Classification based on type of
application

 1. Light duty cylinders

 2. Medium duty cylinders

3. Heavy duty cylinders