Investigation of the causes to autotruck cooling jacket defects

  • 1 University of Chemical Technology and Metallurgy - Sofia, Bulgaria


Defects in the cooling jacket occur for a variety of reasons. This type of details works in severe heat load conditions – fluctuating fluid pressure, mechanical friction and corrosion. The reason for appearance of defects in auto truck engines is often the type of material from which their individual parts are made. For various reasons, they are susceptible to the influence of natural wear, material fatigue and the complex action of many physical and chemical fast-flowing processes.
One of the main parts of internal combustion engines is the cooling jacket. This part operates under severe thermal stress conditions caused by mechanical friction in contact with the piston, fluctuating pressure where the refrigerant fluid moves, and corrosive action from that same fluid containing antifreeze. The listed factors require the material from which this part is made to have strength and good wear and corrosion resistance – prerequisites for a long service life.
Therefore, it is important to identify the exact causes of cooling jacket defects and to found ways to prevent them.
The examined details are analyzed by standard methods for chemical and metallographic analysis, as well as for mechanical tests.



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