MODEL ENGINEERING&TECHNICAL INSTITUTE, WANDOOR Quarterly Examination-2014- Refrigeration & Air-Conditioning 2nd year Mechanical I. 1. 2. 3. 4. 5. II. Answer any questions in one or two sentences Define specific Heat Define Power Define kinetic energy Define solid matter Define loss of head due to friction a)What are the specialty and advantages of centrifugal pumps b) What is belt drive? Explain different belt drives Marks: 50 Time : 1.5 hrs 5x2=10 5 5 III. a) What is priming? 3 b) Draw a neat sketch of a single acting reciprocating pump and explain the working 7 IV. a) What are the advantages of chain drive over flat belt drive? b) Draw a foot valve and explain the working c) Draw the sketch of Bevel gear and explain the working 2 4 4 MODEL ENGINEERING&TECHNICAL INSTITUTE, WANDOOR Quarterly Examination-2014-- Refrigeration & Air-Conditioning 2nd year R&AC THEORY Marks:100 Time :3hrs PART-A I. fill in the blanks:1. The movement of free electronics is called__________ 2. Occupied space by substance is called ___________ 3. A compressor is used in ___________system 4. The commutator is used in _______ system 5. The commutation is the part of ___________ motor 6. Brine is _________ refrigerant 7. The compressor is called the __________ of a refrigeration 8. The name of R22 is___________ 9. A thermometer senses __________ heat 10. Piston pin is called _______ pin 10x2=20 PART-B (Answer any five full questions) II. a) What are the six common methods of refrigerating process. 3 b) What is the different between Heat & and temperature . 2 c) What are the different between air cooled condenser and water cooled condenser 4 d) Draw a neat sketch of forced draft cooling tower and explain the working 7 OR III. a) What are the characteristics of good refrigerant 4 b) Describe the working principle of a Thermostatic Expansion valve with a neat sketch 8 c) What is Dry Expansion 2 d) What is compression COP 2 IV. V. VI. a) What is the advantages of heat exchanges b) Describe the working of flooded evaporator with a neat sketch c) What are the difference between Hermetic compressor and open type compressor? d) What is the use of dehydrator in Refrigeration system OR a) Draw a neat sketch of pressure type water cooler and explain the 2 8 4 2 working 8 b) What are the different between compound gauge and high pressure gauge? c) What is latent heat? 4 4 a) Draw a neat sketch of Hermetic compressor and explain the working 8 b) Write a short note in swaging tool, flaring tool, spring bender and pinch off tool 8 OR VII. VIII. a) What is surge tank 2 b) What is defrosting in refrigeration system 2 c) Draw a neat sketch of shell and tube water cooled condenser and explain 8 d) What is refrigerant? 2 e) What is specific Heat? 2 a) Draw a neat sketch of automatic expansion valve & explain its working? 8 b) Write a short note an capillary tube 3 c) What is brine solution 3 d) Name two secondary Refrigerants 2 OR IX. X. a) Draw a lay out of Ice plant and explain how manufacture Ice in the systems 8 b) What is accumulator 3 c) What is Evaporator 3 d) Write the name of five Refrigerant 2 a) What is Refrigeration? 2 b) What is the function of a condenser? 3 c) How do you classify condenser? 3 d) Draw the vapour compressor Refrigeration system cycle and mark. High pressure side and low pressure acting side 8 OR XI. a) Draw the internal view of a Thermostatic switch and explain the working 8 b) What are the difference between condenser and Evaporator 4 c) Write short notes:- 4 a) Thermometer c) Halide torch b) BTU d) Relay MODEL ENGINEERING&TECHNICAL INSTITUTE,WANDOOR Quarterly Examination-2014- Refrigeration & Air-Conditioning 2nd year Drawing PART-A Marks:100 Time:3hrs (Answer any three Questions) I. II. III. IV. V. VI. VII. VIII. IX. X. Inscribe a regular pentagon in a circle where the length of one side is equal to 25mm? Draw a right angled triangle ABC. One short side AB=50mm long and the hypotenuse AC=100mm. long scribe a circle on it Divide a line AB=95mm into 10 equal parts Draw isometric view of cylinder dia:40mm and length 60mm if it is resting on one of its circular bases. Draw the isometric view of the object shown in fig-1 3x10=30 PART-B (1. Question No VI. is compulsory (2. Answer any three questions from the remaining) Draw a neat sketch of different types of evaporators in refrigeration 40 Draw the electrical wiring diagram of a single door refrigerator 10 Draw the neat sketch of flaring tool 10 Draw the neat sketch of internal parts of a reciprocating compressor and mark the parts 10 Draw a neat diagram of natural draft cooling tower 10