B.E./B.Tech. Degree Examination, November/December 2007

B.E./B.Tech. Degree Examination, November/December 2007

Fifth Semester - Mechanical Engineering (Regulation 2004)

ME 1305 - APPLIED HYDRAULICS AND PNEUMATICS

Time: Three hours

(Regulation 2004)

Answer ALL questions. 

Maximum: 100 marks

Part A - (10 × 2 = 20 marks) 

1. State four advantages of fluid power.

Ans. Refer Chapter 1, Q. No. 7, Two Marks Q&A, Page No. 1.23. 

2. What is low cost automation?

Ans. Refer Chapter 16, Q. No. 3, Two Marks Q&A, Page No. 16.39. 

3. What are the major components of a hydraulic system?

Ans. Refer Chapter 1, Q. No. 16, Two Marks Q&A, Page No. 1.24.

4. What is a positive displacement pump?

Ans. Refer Chapter 4, Q. No. 6, Two Marks Q&A, Page No. 4.45.

5. What are the control functions of different valves in hydraulic systems? 

Ans. Refer Chapter 6, Q. No. 1, Two Marks Q&A, Page No. 6.47.

6. What is an intensifier?

Ans. Refer Chapter 9, Q. No. 12, Two Marks Q&A, Page No. 9.35.

7. What are the reasons for pressure drop in pneumatic lines?

The reasons include sudden change in volume, leakage exist in the circuit line, change in temperature, bends, and restrictions present in the pipe line.

8. How are the air compressors classified?

Ans. Refer Chapter 11, Q. No. 2, Two Marks Q&A, Page No. 11.20.

9. Define fluidics.

Ans. Refer Chapter 15, Q. No. 1, Two Marks Q&A, Page No. 15.28.

10. What is a regenerative system in a pneumatic circuit?

Ans. Refer Chapter 8, Q. No. 2, Two Marks Q&A, Page No. 8.36. 

Part B - (5 × 16 = 80 marks)

11. (a) What are the desirable properties of hydraulic fluids? Discuss any eight of them in detail.

Ans. Refer Chapter 2, Sections 2.4-2.5, Page No.2.4.

 [OR]

(b) (i) What is Reynolds number?

Ans. Refer Chapter 3, Section 3.7, Page No.3.10.

(ii) How is Reynolds number determined?

Ans. Refer Chapter 3, Section 3.7, Page No.3.10.

(iii) Draw fluid power symbols of any six different types of valves.

Ans. Refer Chapter 7, Sections 7.4-7.7, Page No.7.4.

12. (a) (i) Explain the construction and working of a gear pump.

Ans. Refer Chapter 4, Section 4..6, Page No.4.8.

(ii) How is the capacity of a variable displacement vane pump is adjusted? Explain with a diagram.

Ans. Refer Chapter 4, Section 4.14, Page No.4.18.

[OR]

(b) (i) What is cylinder cushioning? Explain with a diagram.

Ans. Refer Chapter 5, Section 5.5, Page No.5.6.

(ii) Explain with a diagram the working of a telescopic cylinder.

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

13. (a) (i) How does a pilot operated direction control valvè function? Explain with a diagram.

Ans. Refer Chapter 6, Section 6.7.4, Page No.6.6.

(ii) Discuss with a diagram the working of a non-return valve. 

Ans. Refer Chapter 6, Section 6.7, Page No.6.5.

[OR]

 (b) (i) Two hydraulic cylinders have to work in sequence. Design a suitable circuit. Draw the circuit.

Ans. Refer Chapter 8, Section 8.10, Page No.8.13.

 (ii) An hydraulic cylinder is used for an industrial application. It has been decided to use an accumulator as leakage compensator. Design a circuit to fulfill these requirements.

Ans. Refer Chapter 9, Section 9.10.1, Page No.9.10.

14. (a) (i) Discuss the working principle of an air compressor.

Ans. Refer Chapter 11, Section 11.3, Page No.11.2.

(ii) Discuss the functions of FRL unit.

Ans. Refer Chapter 11, Section 11.10, Page No.11.15.

[OR]

(b) (i) Explain the working of a pneumatic speed control circuit.

Ans. Refer Chapter 13, Section 13.8, Page No.13.12.

(ii) What is time delay circuit? Discuss with an example.

Ans. Refer Chapter 13, Section 13.10, Page No.13.16.

15. (a) (i) What is the selection criteria for pneumatic components?

Ans. Refer Chapter 16, Section 16.12, Page No.16.14.

(ii) What are the factors considered during the installation of pneumatic systems? 

Ans. Refer Chapter 17, Section 17.2, Page No.17.1.

(iii) What are the advantages of using fluidic systems?

Ans. Refer Chapter 15, Section 15.3.1, Page No.15.3. •

[OR]

(b) (i) What is Coanda effect? Explain with a diagram.

Ans. Refer Chapter 15, Section 15.3.1, Page No.15.3.

(ii) Design a circuit with air pilot control of a double-acting cylinder.

Ans. Refer Chapter 13, Section 13.4.2, Page No.13.6.

(iii) Explain with a circuit diagram how is the control of an air motor is achieved. A flow control valve is used to adjust the speed of the motor.

Ans. Refer Chapter 13, Section 13.8.2, Page No.13.12.