B.E./B.Tech. Degree Examination, November/December 2016

B.E./B.Tech. Degree Examination, November/December 2016 

Mechanical Engineering (Regulation 2008/2010)

Time: Three hours

APPLIED HYDRAULICS AND PNEUMATICS

Answer ALL questions. 

Maximum: 100 marks

Part A - (10 × 2 = 20 marks)

1. Define Reynold's Number.

Ans. Refer Chapter 3, Q. No. 7, Two Marks Q&A, Page No. 3.28. 

2. List the general types of hydraulics fluids.

Ans. Refer Chapter 2, Q. No. 22, Two Marks Q&A, Page No. 2.24. 

3. Why cushioning mechanism is needed for hydraulic cylinders? 

Ans. Refer Chapter 5, Q. No. 11, Two Marks Q&A, Page No. 5.31. 

4. List the merits and demerits of gear pump.

Ans. Refer Chapter 4, Q. No. 12, Two Marks Q&A, Page No. 4.45. 

5. Draw the symbol of shuttle valve and write its use.

Ans. Refer Chapter 6, Q. No. 16, Two Marks Q&A, Page No. 6.49.

6. Why flow control valve is essential in hydraulic circuits?

Ans. Refer Chapter 6, Q. No. 29, Two Marks Q&A; Page No. 6.51.

7. What are the functions of the regulator in pneumatic systems? 

Ans. Refer Chapter 11, Q. No. 13, Two Marks Q&A, Page No. 11.21.

8. When synchronizing circuit is required?

Ans. Refer Chapter 8, Q. No. 8, Two Marks Q&A, Page No. 8.37.

9. What is meant by servo systems?

Ans. Refer Chapter 6, Q. No. 34, Two Marks Q&A, Page No. 6.52.

10. List the uses of ladder diagrams.

Ans. Refer Chapter 14, Q. No. 13, Two Marks Q&A, Page No. 14.17.

Part B - (5 × 16 = 80 marks)

11. (a) (i) Explain the applications of fluid power system with example. List its merits and demerits.

Ans. Refer Chapter 1, Section 1.6, Page No. 1.7.

(ii) Explain the fluid characteristics of fluid used in hydraulic system.

Ans. Refer Chapter 2, Section 2.4, Page No. 2.4.

[OR]

(b) (i) Write short notes:

(1) Laminar flow

Ans. Refer Chapter 3, Section 3.6.1, Page No. 3.9.

(2) Turbulent flow

Ans. Refer Chapter 3, Section 3.6.2, Page No. 3.10.

(3) Pascal's law applications

Ans. Refer Chapter 3, Section 3.5, Page No. 3.5.

(ii) List the various valves and fittings used in hydraulic systems. Explain their associative losses and its preventions.

Ans. Refer Chapter 3, Section 3.15, Page No. 3.17.

12. (a) Explain with suitable sketch the working of radial and axial piston pumps.

Ans. Refer Chapter 4, Sections 4.19 & 4.16, Page Nos. 4.26 & 4.21.

[OR]

(b) (i) With neat sketch explain the construction of Telescopic cylinder and state its application with example.

Ans. Refer Chapter 5, Section 5.6, Page No. 5.8.

(ii) What is meant by rodless cylinder? State its application.

Ans. Refer Chapter 5, Section 5.8.2, Page No. 5.10.

13. (a) Classify the direction control valves in terms of position and explain each with neat circuits.

Ans. Refer Chapter 6, Sections 6.9 & 6.10, Page No. 6.12.

[OR]

 (b) What is the function of a throttle valve? Draw and explain the meter-in, meter-out and bleed-off circuits.

Ans. Refer Chapter 8, Section 8.14, Page No. 8.23.

14. (a) Draw the layout of the complete pneumatic system and explain its subsystem. 

Ans. Refer Chapter 1, Section 1.8, Page No. 1.15..

[OR]

(b) Draw a sequential pneumatic circuits for the following sequence A+ A- B+ C+ B- C– using cascade method.

Ans. Refer Chapter 13, Example 13.9, Page No. 13.28.

15. (a) (i) Explain the working of electro hydraulic servo systems with neat sketch.

Ans. Refer Chapter 8, Section 8.20, Page No. 8.34.

(ii) What is meant by fluidics? Name some fluidic devices and its uses. Ans. Refer Chapter 15, Section 15.2, Page No. 15.1.

 [OR]

(b) (i) Two double-acting pneumatic cylinders A and B, with double-solenoid valves have to work in the following sequences A+, B+, A-, B-. Draw a ladder diagram and indicate the input and output devices. Both the cylinders have limit switches.

Ans. Refer Chapter 13, Example 13.5, Page No. 13.23.

(ii) Write short notes on failure and trouble shooting in pneumatic circuits. 

Ans. Refer Chapter 17, Section 17.7, Page No. 17.16.