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saurabhjain

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  1. saurabhjain

    Make a sentence and give a word...

    hiiiiiiii i`m starting here a new game...here the person who is before you will write a word and you have to say anything but THAT WORD should come in ur sentence....and after that you have to write A WORD for the others............but be sure the word you r writing for others should be an Engineering term I start with word Gear
  2. What is the difference between hard water and soft water ? 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
  3. Explain the use of the study of the heat balance of an engine 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
  4. Casting is a major manufacturing process which is mostly used in heavy industries. Most of the components like outer casing of turbine, lathe bed, valve casing, hydro turbine blades, Pelton wheel, Francis runner and many other parts of major machinery are made by the casting. The cast product has low strength compare to forging but any difficult parts can be cast by this technology. Types of Casting: Casting is widely used any many different shapes and material can be cast by it. There are various method of casting available which are used for different shapes and material. Casting has following types. Sand Casting: It is widely used for casting different process. Sand is easily available and has high refectory property so it is used in casting. It is done by following steps. Design is made by using software or manually. A wooden pattern is created in pattern shop. Generally patterns are made into two half and can be increased accordingly to complexity. The pattern is placed into the flask and mixture of sand and clay with water pour into it. The runner, riser, core, gating system is also fit into it. When the mould gets hard the pattern is removed from mould and molten metal pour into it. The metal is allowed to get solidify into the casting. After solidification cast is removed from casting and send to machine shop for machining. The sand casting is used for all metal and at low cost. An another advantage is that it can be used for very complex shape. It gives poor surface finish. Shell Casting: It is an another method of casting and used to cast thin section like turbine blade etc. This casting is different from sand casting. A metallic pattern is used in this type of casting. It consist following steps. First a metallic pattern is cast. The metal is used for casting is generally aluminum or cast iron The patterns is heated up to 250 degree and put into flask. The flask is filled with sand resin mixture. The resin gets solidify immediately after gating contact with heated pattern. After the sand solidify the pattern and the extra sand taken out. Now a shell of cavity is created. This shell is further heated into burner which allow proper bond. The metal is poured into the shell and allows to solidify. After solidification cast is removed from shell and send for machining. Investment Casting: In this type of process, wax pattern is used. The pattern is first created by wax dipped into refectory material. This refectory material make a shall outside the wax pattern. After it mould is heated which allow waxing out from mould. Now the molten metal poured into cavity formed by it and allows solidifying. The cast is taken out after proper solidification of cast and send for machining. The main advantage of this process is that a very high accuracy and surface finish can obtain by it. It is used for complex shape and batch production. Plaster Mould Casting: These method uses plaster mould for casting. First plaster mould is created using patterns. After removal of pattern, the plaster mould allows to dry into an oven. After dried, molten metal is poured into it and allow solidifying. After complete solidification cast is sand to the machine shop. Mostly zinc and aluminum is used as molten metal. This casting is used to create prototype. Ceramic Mold Casting Ceramic mold casting is same as investment casting but it does not use wax pattern. The slurry of ceramic and liquid binder is pour on pattern which is easily solidify. There is no wax pattern is used so there is no limitation of size of casting. This type of casting is mainly used to cast heavy component like valve bodies, military equipment etc. Pressure Dies Casting: This casting is mostly used to cast aluminum, lead etc. In this casting a liquid metal is pumped at high pressure into a metallic die and allow to solidify. The metal is allowed to solidify there and take out after solidification .The die is again used for next cast. It is well suitable for batch production of casting low melting point metal. It is not suitable for high melting temperature metals. The tooling cost is also high. Centrifugal Casting: It is one of the most suitable casting processes of casting symmetrical cylindrical component. In this process a liquid metal is poured at the center of a rotating die. The die rotate and a centrifugal force act on the molten metal which forces it to towards circumference. It is used to create hollow shape. The light impurities crowed near center which is removed by machine. This process eliminates the use for core and gating system. This type of casting is used to make pipes etc. Continuous Casting: It is a different casting process which is used to create continuous cast. In this process we do not use mould or cope and drag. It is different in principle. In this process the molten metal poured into a trash which is connected to a copper pipe. The copper pipe is surrounded by water cooling. The metal is directly or immediately cooled after when running through pipe. The casting product takes out from other side. This process continuously run and molten metal continuously pour into it. It is used to create square or other shape simple block which further used for rolling or other process. These all are main types of casting.
  5. Why a drill jig should have four legs, no more and no less ? 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 design of jigs.pdf
  6. Selection of material is an important aspect for manufacturing industries . The quality of product is highly depends upon its material properties. These properties are used to distinguish materials from each other. For Example: A harder material is used to make tools.A ductile material is used to draw wires. So the knowledge of mechanical properties of material is desirable for any mechanical student or for any person belongs to mechanical industries. This post brings top 18 mechanical properties. Mechanical properties of material: There are mainly two types of materials. First one is metal and other one is non metals. Metals are classified into two types : Ferrous metals and Non-ferrous metals. Ferrous metals mainly consist iron with comparatively small addition of other materials. It includes iron and its alloy such as cast iron, steel, HSS etc. Ferrous metals are widely used in mechanical industries for its various advantages. Nonferrous metals contain little or no iron. It includes aluminum, magnesium, copper, zinc etc. Most Mechanical properties are associated with metals. These are #1. Strength: The ability of material to withstand load without failure is known as strength. If a material can bear more load, it means it has more strength. Strength of any material mainly depends on type of loading and deformation before fracture. According to loading types, strength can be classified into three types. a. Tensile strength: b. Compressive strength: 3. Shear strength: According to the deformation before fracture, strength can be classified into three types. a. Elastic strength: b. Yield strength: c. Ultimate strength: #2. Homogeneity: If a material has same properties throughout its geometry, known as homogeneous material and the property is known as homogeneity. It is an ideal situation but practically no material is homogeneous. #3. Isotropy: A material which has same elastic properties along its all loading direction known as isotropic material. #4. Anisotropy: A material which exhibits different elastic properties in different loading direction known as an-isotropic material. #5. Elasticity: If a material regain its original dimension after removal of load, it is known as elastic material and the property by virtue of which it regains its original shape is known as elasticity. Every material possess some elasticity. It is measure as the ratio of stress to strain under elastic limit. #6. Plasticity: The ability of material to undergo some degree of permanent deformation without failure after removal of load is known as plasticity. This property is used for shaping material by metal working. It is mainly depends on temperature and elastic strength of material. #7. Ductility: Ductility is a property by virtue of which metal can be drawn into wires. It can also define as a property which permits permanent deformation before fracture under tensile loading. The amount of permanent deformation (measure in percentage elongation) decides either the material is ductile or not. Percentage elongation = (Final Gauge Length – Original Gauge Length )*100/ Original Gauge Length If the percentage elongation is greater than 5% in a gauge length 50 mm, the material is ductile and if it less than 5% it is not. #8. Brittleness: Brittleness is a property by virtue of which, a material will fail under loading without significant change in dimension. Glass and cast iron are well known brittle materials. #9. Stiffness: The ability of material to resist elastic deformation or deflection during loading, known as stiffness. A material which offers small change in dimension during loading is more stiffer. For example steel is stiffer than aluminum. #10. Hardness: The property of a material to resist penetration is known as hardness. It is an ability to resist scratching, abrasion or cutting. It is also define as an ability to resist fracture under point loading. #11. Toughness: Toughness is defined as an ability to withstand with plastic or elastic deformation without failure. It is defined as the amount of energy absorbed before actual fracture. #12. Malleability: A property by virtue of which a metal can flatten into thin sheets, known as malleability. It is also define as a property which permits plastic deformation under compression loading. #13. Machinability: A property by virtue of which a material can be cut easily. #14. Damping: The ability of metal to dissipate the energy of vibration or cyclic stress is called damping. Cast iron has good damping property, that’s why most of machines body made by cast iron. #15. Creep: The slow and progressive change in dimension of a material under influence of its safe working stress for long time is known as creep. Creep is mainly depend on time and temperature. The maximum amount of stress under which a material withstand during infinite time is known as creep strength. #16. Resilience: The amount of energy absorb under elastic limit during loading is called resilience. The maximum amount of the energy absorb under elastic limit is called proof resilience. #17. Fatigue Strength: The failure of a work piece under cyclic load or repeated load below its ultimate limit is known as fatigue. The maximum amount of cyclic load which a work piece can bear for infinite number of cycle is called fatigue strength. Fatigue strength is also depend on work piece shape, geometry, surface finish etc. #18. Embrittlement: The loss of ductility of a metal caused by physical or chemical changes, which make it brittle, is called embrittlement.
  7. Bolt vs Screw - Open end discussion The difference in design , forces , uses , material - which to use when and more..... 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
  8. List three principal factors that influence engine performance ? 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
  9. saurabhjain

    Revolver parts.jpg

    From the album: Engineering Images 4

  10. saurabhjain

    Attendance Please

    Dear Mechanical Engineering members, I want you all to visit iMechanical Engineering Forum once every day and for same I am starting "Attendance Please" Post. Many of us read as guests, some of them just sign in and sign out and then I request every one to mark your attendance by replying to this post. Your presence will make all members active and visible on the board.
  11. View this quiz Machine Design Quiz 1 Questions on the concepts of Machine Design Submitter saurabhjain Time 5 minutes Type Graded Mode Submitted 04/21/2017 Category Mechanical Engineering Quiz  
  12. saurabhjain

    Engineering Word Game

    This is word building game but words related only to engineering... First word: Mechanical Next word starting with L but related to Engineering ...
  13. Why efficiency of Gas turbine is lower compared to IC engine ? 1. You can answer this question 2. You can like the best answer 3. You can share the question.
  14. Why gas containers are mostly cylindrical in shape? 1. You can answer this question 2. You can like the best answer 3. You can share the question.
  15. What do you understand by the Hooke`s Coupling what are its purposes? 1. You can answer this question 2. You can like the best answer 3. You can share the question.
  16. What are the rules that must be kept in mind while designing castings? 1. You can answer this question 2. You can like the best answer 3. You can share the question.
  17. Difference between Bolt,Screw and Stud. 1. You can answer this question 2. You can like the best answer 3. You can share the question.
  18. List down the ways the classification of IC Engine can be done 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. You know that diesel engine is the most appropriate choice of the engineers when it comes to drive heavy automobile like trucks, aircraft, ships etc. But what makes it so torque, is it the engine design, working cycle or something else. Please share your deep analysis to answer this questions
  20. What is 'CC' of a bike? How does it matter? 1. You can answer this question. 2. You can like the best answer. 3. You can share the question
  21. saurabhjain

    Machine Design II ppt

    Version

    9,188 downloads

    Presentation on Design of- Clutch Brake Belts Chain Gears
  22. saurabhjain

    forging

    From the album: Engineering images 10

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