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    We welcome comments on each picture of engines...
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    name -surya prakash ojha government polytechnic jamui eng batch 2016-2019 jamui bihar in 4th sem ,diploma in mechanical. i want to prepare for exam and for this i want help of other students on whatsapp.new group https://chat.whatsapp.com/IpjBL3tULgZKexMJWjtrK8
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    1. It's not oil the best name is brake fluid as it consists a lot of material inside such as (silicone, glycol ether/borate ester, mineral oil) 2. One of the main things for BF, it must have a high boiling point to avoid vaporizing in the lines this is why we need to change the brake fluid from time to time as it has tendency to absorb water which will lower its boiling temperature leading to change part of the fluid into moisture and vapour inside the brake circuits and this will create vapour lock leading to being compressible and once it became compressible the brake foot force will not be transferred to the other brake parts (cylinders,brake pistons, ...) We have many types of BF each has its own dry/wet boiling temperature such as:- DOT3 (dry 205C/401F- wet 140C/284F) DOT4 (dry 230C/446F - wet 150C/311F) DOT5 (dry 260C/500F - wet 180C/365F) *Hygroscopic means (water absorbing)
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    Concept of heating is just simple with respect to welding. Majorly Pre or post heating in welding is to relieve stresses which are used to developed during welding. Pre heating: Power saving - by pre heating, heat gradient can be reduced and so to control heat generation, low heat input can be given and so process characteristics can be reduced accordingly Reduction in internal residual stresses - the stresses will are already inside the material can reduce the strength of the weld, to avoid that, pre treatment can be used Post heating: Post heating or annealing or normalizing is done mainly to reduce the thermal stresses developed during welding To relieve Hydrogen embrittlement in which Hydrogen has entrapped during welding from moisture or the filler material
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    Pre-heat is required for the following reasons: (1) It lowers the cooling rate in the weld metal and base metal, producing a more ductile metallurgical structure with greater resistant to cracking. (2) The slower cooling rate provides an opportunity for any hydrogen that may be present to diffuse out harmlessly without causing cracking. (3) It reduces the shrinkage stresses in the weld and adjacent base metal, which is especially important in highly restrained joints. (4) It raises some steels above the temperature at which brittle fracture would occur in fabrication. Post heating is required to remove further residual stresses present in the weld pool after heat treatment process also. If post heating is not done, then residual stresses develops as cracks and propagates throughout, resulting in the failure of the material. Also Preheat/Post weld heat treatment can be used to help ensure specific mechanical properties, such as notch and toughness.
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    Version Ed. 1, 2006


    AISC Steel Design Guide 21: Welded Connections—A Primer for Engineers
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    well in except that both of them are Dassault Systèmes's products . there is a little difference between them. Basically , Solidworks is a CAD (computer aided design) software - the best of it's kind i assume - Simple to manipulate , easy to learn and used by almost every single industry in the world . CATIA is A CAM software , indeed it's better than solidworks in some modules such as surfacing and kinematics. But the main idea is that in CATIA you can not only create a mechanism , but a factory in which it will be produced, the machining processes required, and even you can simulate ergonomics studies as well, like weather the current layout of a plant will be comfortable for workers to work or not. So you can simulate the whole thing within a virtual reality, including, and of course, rendering. However CATIA is almost exclusively used in Aviation and Automotive industries. So there is no doubt you need to learn them both ... because let's say if you want to create an airplane Use CATIA to create the surface and to simulate the manufacturing process and Solidworks would easily handle the engines
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    thankx...nice explanation
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    Enter u r whatsapp number Share your knowledge.. And improve your knowledge My number 8870349108
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    mini stirling engine

    From the album: Engines

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    Diesel Engines we dont need the Spark Plug the Calorific value of the Diesel is more when compared with petrol Engine. For less colorific value we do not get more horse power. But diesel natually have more heat developed during combustion thus developing more power than petrol engines.