The document classifies hydraulic actuators into linear and rotary types, detailing various cylinder constructions like single acting, double acting, and their special forms. It discusses design considerations for hydraulic cylinders, such as required thrust, speed, and service life, and also reviews hydraulic motors including their advantages like compactness and high power-to-weight ratio. Additionally, it mentions limitations of gear motors and other rotary actuator types.

1. Hydraulic Actuators

2. Classification
• Linear actuators: (40/28-500)
Converts hydraulic energy into straight line
motion. “Linear motors”
• Rotary actuators:
Converts hydraulic energy into rotational motion
Limited rotary & hydraulic motors

3. Basic Construction of hydraulic Cylinder

4. Types of Cylinders

5. Single acting Ram type cylinder

6. Single acting Spring return

7. Double acting cylinder with single piston rod

8. Double acting cylinder with double piston rod

9. Tandem cylinder

10. Telescopic Cylinder

11. Telescopic Cylinder

12. Nested cylinder

13. Rotating Cylinder

14. Mountings of Hydraulic Cylinders

15. Design Consideration for hydraulic cylinders
1)Thrust Required on operating cylinder:
Maximum force, decide operating pressure, calculate area
of piston.
2) Speed and stroke length
3) Type of construction:
Machine tool cylinder, Construction machinery,
Steel mill and heavy industrial equipments, Aviation
equipments

16. Design Consideration for hydraulic
cylinders
4) Type of mountings
5) Service life
6) Operating Environment
7) Lateral loads and buckling failure.

17. Rotary Actuators
• Vane type limited rotary actuator
• Dual piston type actuator
• Gear Motor
• Vane Motor
• Piston Type motor
Hydraulic Motors are equivalent of electric
motors. Hydraulic motors convert pressure
energy into continuous rotation.

18. Limited Rotary Actuator

19. Limited Rotary Actuator

20. Dual Piston type Limited Rotary Actuator

21. Dual Piston type Limited Rotary Actuator

22. Hydraulic Motors
• Advantages:
1) Compact in size
2) High power to weight ratio. (Smaller in size)
3) Wide range of speed
4) Frequent starting, stopping, reversing and sudden
stopping is possible.
5) It can provide variable torque by using PCV.
6) Hydraulic motors are explosion proof in nature.

23. Gear Motors

24. Gear Motors
• Gear motors suffers from leakage at low speed
• Medium speed and low torque.

25. Vane Type motor

26. Piston Motor