saurabhjain

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Everything posted by saurabhjain

  1. With so much scientific tools, why do designs fail? Please add your comments by replying below and invite all your friends for participation.
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    Questions on the concepts of Machine Design
  2. From the album Engines

  3. The manufacture of parts by machining. Introduction. 1.1 Introduction Every engineer must have an integral general culture and, within this, of course, a culture of the profession. Part of the culture of the mechanical engineer is to know the history of engineering, and in the particular case of this blog is important to start by knowing very briefly the history of machine tools. Annex I, which deals with the evolution of machine tools [1], will be presented later. The industrial revolution that emerged with the steam engine would not have been possible if a machine tool capable of manufacturing the essential parts of the invention that James Watt had synthesized: the steam engine had not been built first. By the way, for Watt to come to his invention there had to be others who preceded him and made their own previous discoveries in the same field of pressure steam, so that, as is almost always the case, Watt compiled that knowledge , Organized them, systematized them, added them more and built, helped by Wilkinson and his boring machine, the first steam engine. And before that, and after that, it's always been that way. Without machine tools there is no possible development. The machine tools manufacture the pieces that are seen daily without being given the proper attention: those of the bus that takes passengers, those of the thermoelectric or the generating set that produces the electricity, those of the dairy combination that processes the milk , The equipment used by the doctor, the equipment that perforates to search for or pump oil from the depths of the earth, those of the sugar mill. And as if all this were not enough, machine tools manufacture other machine tools, it could be said figuratively that they are the only machines that guarantee the continuity of their species. Note: Why "machine tools" and not "machine tools"? In the Castilian language the nouns formed by two nouns form the plural only with the first of them. Thus, other examples may be: teacher guides; keywords; Strawberries mother. However, sometimes the second of the two nouns can be considered as an adjective, and then it would be "machine tools". In this blog the first variant is preferred. Like this
  4. What is the difference between wheel dressing and wheel truing ? You can answer this question. You can like the best answer. You can share the question You can get updates of new questions on Facebook linkedin twitter & google plus
  5. What useful information are obtained from tensile test of ductile material You can answer this question. You can like the best answer. You can share the question You can get updates of new questions on Facebook linkedin twitter & google plus
  6. View this quiz Machine Design 1 Questions on the concepts of Machine Design Submitter saurabhjain Time 5 minutes Type Graded Mode Submitted 04/21/2017 Category Mechanical Engineering Quiz  
  7. View this quiz Automobile Engineering Quiz 1 Questions on the concepts of automobile engineering. Submitter saurabhjain Time 5 minutes Type Graded Mode Submitted 04/20/2017 Category Automobile Engineering  
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    Questions on the concepts of automobile engineering.
  8. may be he need to know which book to read?
  9. What is the least count of vernier caliper ? For what all purposes we use vernier caliper? 1. You can answer this question 2. You can like the best answer 3. You can share the question.
  10. What are the differences between pipe and tube ? 1. You can answer this question 2. You can like the best answer 3. You can share the question.....
  11. Explain why washers are used? You can answer this question. You can like the best answer. You can share the question You can get updates of new questions on Facebook linkedin twitter & google plus
  12. Why Tractors have their exhaust system(Silencer) fitted in the front of the vehicle,while other automobiles have their silencer at their back? 1. You can answer this question 2. You can like the best answer 3. You can share the question.
  13. Why different types of sound are produced in different bikes though they say run on SI engine ? 1. You can answer this question 2. You can like the best answer 3. You can share the question.
  14. What is the difference between knocking and detonation in IC engine? 1. You can answer this question. 2. You can like the best answer. 3. You can share the question You can get updates of new questions on Facebook linkedin twitter & google plus
  15. As per Google translate An acceptable vision, but where the harmony of the system remains
  16. What is the difference between lapping and honing You can answer this question. You can like the best answer. You can share the question You can get updates of new questions on Facebook linkedin twitter & google plus
  17. Difference between Turbocharger and Supercharger in Tabular Form S.no Turbocharger Supercharger 1. Turbocharger is a forced induction system that compresses the atmospheric gases and sends it to the engine cylinder. Super charger is also a forced induction system. It compresses the atmospheric air and sends it to the engine cylinder. 2. It uses exhaust gases for its energy. It is connected to the crankshaft of the engine for its energy. 3. It is not directly connected to the engine. It is directly connected to the engine through belt. 4. It has smog altering equipment which helps in lowering the carbon emission. It doesn’t have wastegate, so the smog emits from the supercharger. 5. It spins with a speed upto 150000 rpm. It spins with a speed upto 50000 rpm. 6. It is much quieter than supercharger. It is not so quieter. 7. It is less reliable. It is more reliable. 8. Maintenance is not easy. Maintenance is easy. 9. Turbocharger delivers their boost better at high rpm. Supercharger can deliver their boost at lower rpm. 10. It is more efficient. It is less efficient. 11. The compressed air in turbocharger has high temperature. The compressed air in supercharger has less temperature. 12. It requires intercooler for the compressed air to lower its temperature. It may or may not require intercooler. But in some types, it requires intercooler. 13. It is more complex. It is less complex. 14. It has lag problem due to discontinuous supply of energy. It has negligible lag problem because of continuous supply of energy by crankshaft. 15. The compressor is rotated by the turbine. The compressor is rotated by the engine crankshaft through a belt.
  18. State the difference between turbocharger and supercharger You can answer this question. You can like the best answer. You can share the question You can get updates of new questions on Facebook linkedin twitter & google plus
  19. From the album Engineering images 10

    What are Jigs? Jigs are the work holding device which holds, supports and locate the workpiece and guides tools to perform a specific operation. In other words we can say that, jigs are the device which is used for both purposes of holding the workpiece and guiding the tool. It is a tool which is used to control the location and motion of the tool during the operations. Jigs main purpose is to provide repeatability, accuracy and interchangeability in the manufacturing of products. It is used in the unidimensional machining i.e drilling, taping, reaming etc. Jigs are found to be light in weight and have complex designing. In jigs, gauge blocks are not necessary and the cost of jigs is higher. They are the special tools particularly used in drilling, reaming, tapping and boring Operations. Jigs are not fixed to the machine table until a big operation is not required to perform. What are Fixtures? Fixtures are the work holding device which holds, supports and locate the workpiece but not guides the cutting tool to perform a specific operation. In other words the fixtures are only the work holding device that holds, supports and locate the workpiece in desried position to perform any operation. The main purpose of the fixtures is to hold and locate the workpiece during any machining operation in the industries. And to provide repeatability, accuracy and interchangeability in the manufacturing of products. It is used in multidimensional machining i.e. milling, grinding, turning etc. Fixtures are found to be heavy in weight and have less complex designing. In fixtures, gauge blocks may be provided for effective handling and the cost of fixtures is not so high. Fixtures are specific tools used particularly in milling machine, shapers and slotting machine. Fixtures are fixed to the machine table. Difference Between Jigs and Fixtures in Tabular Form: The various difference between jigs and fixtures in the tabular form are given below: S.no Jigs Fixtures 1. It is a work holding device that holds, supports and locates the workpiece and guides the cutting tool for a specific operation. It is a work holding device that holds, supports and locates the workpiece for a specific operation but does not guide the cutting tool 2. jigs are used in unidimensional machining i.e. drilling,reaming, tapping, etc fixtures are used in multidimensional machining i.e. milling,turning,grinding,etc . 3. Jigs are light in weight. Fixtures are rigid and bulky. 4. Gauge blocks are not necessary. Gauge blocks may be provided for effective handling. 5. The jigs are special tools particularly used in drilling, reaming, tapping and boring operation. Fixtures are specific tools used particularly in milling machine, shapers and slotting machine 6. Usually it is not fixed to the machine table. It is fixed to the machine table. 7. Its cost is more. Its cost is less as compared with the jig. 8. Their designing is complex. Their designing is less complex. Summary of Difference Between Jigs and Fixtures Jigs are the device which is used to holds, supports and locate the workpiece and it guides the cutting tool for a specific operation. Fixtures are the device which is used to hold, support and locate the workpiece and they don’t guide the cutting tool. Jigs are used in unidimensional machining whereas fixtures are used in multidimensional machining. In jigs, gauge blocks is not necessary. In fixtures gauge blocks may provided for effective handling. Jigs are light in weight as compared with the fixtures. The cost of jigs is higher when it is compared with the fixtures. The jigs designing is complex where as fixtures designing is less complex. Jigs are not fitted to the machine table but fixtures are fitted.
  20. From the album Engineering images 10

    During the machining process of the workpiece to give it a desired shape, metal chips are produced. The chips formed may be of continuous, discontinuous and continuous with built up edge type. The types of chips formed in machining process depends upon so many factors, we will discuss it later. Basically there are three types of chips produced in the metal machining and these are continuous, discontinuous and continuous with built up edge. 1. Continuous chips 2. Discontinuous chips & 3. Continuous chips with built up edge (or BUE chips) Let’s discuss about them one by one 1. Continuous Chips If the metal chips formed during machining is without segments i.e. without breakage, than it is called as continuous types of chips. Continuous chips are formed when the ductile material is machined with high cutting speed and minimum friction between the chip and tool face. The conditions which are responsible for the formation of continuous types of chips are (i) Ductile material like mild steel is used. (ii) Bigger rake angle of the tool. (iii) High cutting speed. (iv) Minimum friction between the chip and tool interface. (v) Small depth of cut. Advantages The formation of continuous chips during machining process has the following advantages • Better surface finish to the ductile material. • Less heat generation due to minimum friction between the tool face and chip. • Low power consumption. • Long tool life due to less wear and tear. 2. Discontinuous Chips If the chips formed during machining process is not continuous i.e. formed with breakage is called discontinuous chips. Discontinuous types of chips are formed when hard and brittle metals like brass, bronze and cast iron is machined. Conditions which are responsible for the formation of discontinuous chips are: (i) Low feed rate. (ii) Small rake angle of the tool. (iii) High cutting speed. (iv) High friction forces at the chip tool interface. (v) Too much depth of cut. Advantages The formation of discontinuous types of chips in brittle materials provides good surface finish, increases the tool life and reduces the consumption of power. Disadvantages When discontinuous chips are formed in the ductile materials, the workpiece result in poor surface finish and excessive wear and tear of the tool takes place. 3. Continuous Chips with Built Up Edge Continuous chips with built up edge is formed by machining ductile material with high friction at the chip-tool interface. It is similar to the continuous types of chips but it is of less smoothness due to the built up edge. How Built Up Edge is Formed? When the chip is flows in upward direction and high friction is exist in between the interface of the chip and tool. Due to the high friction between the chip and tool a very intense heat is generated at the nose of the tool. The compressed metal adjacent to the tool nose gets welded to it. This compressed metal welded to the nose is called built up edge. When the chip flows through this built up edge, it gets broken and carried away by the chip and called as built up edge chips, the rest of the built up edge is adhere to the surface of the workpiece and makes it rough. Due to formation of the built up edge the rake angle of the tool gets changed and so is the cutting force. The factors which are responsible for promoting the formation of the BUE chips are: (i) Excessive feed rate. (ii) Small rake angle of the tool. (iii) Low cutting speed. (iv) Lack of coolant and this increase the friction between the chip tool interfaces. Advantages The making of the BUE has one advantage i.e. it protects the tool from getting damaged from high friction and temperature generated during machining process and hence the tool life increases. Disadvantages The formation of these types of chips results in rough surface finish, change in the rake angle and cutting forces. Comparison between Continuous, Discontinues and Continuous Chips with Built up Edge in Tabular Form are: S.no Factors Continuous Chips Discontinuous Chips Continuous chips with Built Up Edge (BUE) 1. Material types Ductile Brittle, ductile but hard Ductile 2. Rake angle Large Small Small 3. Cutting speed High Medium or high Low or medium 4. Friction between chip tool interface Minimum Maximum Maximum 5. Depth of cut Small High Medium