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Showing most liked content since 12/18/2017 in Blog Comments

  1. 2 points
    There are two reasons why cooling is required in I.C. Engines. Heat is produced due to burning of fuel inside the engine. Due to heat, thermal stress develops in the engine components. This results in unwanted change in shape (Expantion and contraction). For proper funtioning the moving components should be in there desired shape and size. Other important reason of cooling is for proper lubrication. Yes, due to excess heat the engine oil looses its vicosity and the moving components will not get proper lubrication. Every fulid have a boiling point. At a particular temprature it starts to convert into vapours. Without cooling piston, Bigend, Smallend, crank bearings,Cam, Valves and other mating parts will sieze.
  2. 1 point
    The purpose for a governor on at CI engine is the same as the purpose for a governor on any machine: to maintain constant speed under varying load conditions. DrD
  3. 1 point
    There are 3 reasons for this point. "Why Tractors have vertical exhaust in the front" 1. Design level reason : Tractor is made of 2 piece construction. The rear portion (with the rear axle and drive line) can be seperated from the front portion (with engine, transmission). Hence, the silencer and exhaust tail pipe has to be kept along with the front part of the tractor. If the exhaust was to be facing the ground, then the hot gas will blow on the Driver's legs and will cause uncomfort for the user. Hence, the exhaust gas is sent vertically upward. 2. Functional level reason : If Silencer has to be placed facing the rear, (as in car), then the silencer has to be kept at the bottom. If the exhaust tail pipe is kept at a lower level, the fast blowing exhaust gas will lift up the loose sand in the crop field, now, this has multiple negative impacts 2.1. Top layer of any crop field is the fertile sand, which will get blown-off if tractor silencer is fitted like in cars. If this is allowed, every time, tractor is used, the crop field will loose its fertile sand and ultimately will become barren land. 2.2. Another effect, is these blown-off loose sand, will fall and settle on the crops, forming a layer which will cover the crop and thus stopping the Photosynthesis process of the crops. So the crop yield will be badly affected 3. Yes, keeping the silencer and tail pipe at the bottom will have other packaging issue, where, due to the articulation in crop fields, there is every chance of the silencer getting damaged due to ground hits. By the way , I m in Automobile Service Industry for the last 12 years.
  4. 1 point

    What is priming & why it is done ?

    During priming of a pump, its impeller is fully submerged in the liquid (say water) to remove any air trap (any kind of cavity that can lead to pressure drop), vapors, etc. This is important because lower density fluid produces a head rise proportional to the ratio of its density to the liquid to be pumped. If the pump is placed above the liquid's upper surface, then suction line has a cavity that does not allow proper suction. To avoid this, priming is necessary. This is for centrifugal pumps and not for positive displacement pumps.
  5. 1 point
    Lisho Thomas

    Why tyres are made black in color?

    Tyres are mixture of various rubbers with carbon black added. Carbon black improves traction and wear resistance of pure rubber. Another reason is that black color has higher absorption capability by which the tyre of any vehicle becomes adhesive to road