PSI - Issue 3

J.L. González et al. / Procedia Structural Integrity 3 (2017) 41–47 Author name / Structural Integrity Procedia 00 (2017) 000–000

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Conclusion It was determined that the root cause of the failure was the fatigue fracture of one of the four bolts of the cylinder crown, which when fractured promoted the fracture of the other three bolts, so that crown fell into the chamber Of combustion of the cylinder, blocking the displacement of the piston and generating buckling and fracture of the connecting rod and this went out by the wall of the cylinder and causing the observed damage in the monoblock. The cause of cylinder crown fatigue of cylinder B3 was excessive tightening torque during installation which generated high stresses and reduced fatigue strength caused by a slightly lower hardness of the failed bolt. Acknowledgements The authors would like to acknowledge the National Polytechnic Institute, the National Council of Science and Technology (CONACYT) and the Analysis Integrity of Pipelines Group (GAID-IPN) for the support to carry out this research. References González Velázquez, J. L., 2013. Mecánica de fractura, 2a. Edición, México Ed. Limusa. Wahab et. al., 2014. Effect of Heat Treatment on Fracture Toughness of AISI 4140 Steel. Minia Journal of Engineering and Technology, 33, 1. http://www.turula.com/cgi-bin/bolt.pl , 2017.