<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>1815-5944</journal-id>
<journal-title><![CDATA[Ingeniería Mecánica]]></journal-title>
<abbrev-journal-title><![CDATA[Ingeniería Mecánica]]></abbrev-journal-title>
<issn>1815-5944</issn>
<publisher>
<publisher-name><![CDATA[Facultad de Ingeniería Mecánica. Instituto Superior Politécnico "José Antonio Echeverría"]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1815-59442019000300156</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Análisis de la falla de pernos de fijación de las zapatas polares de un motogenerador]]></article-title>
<article-title xml:lang="en"><![CDATA[Failure analysis of polar shoes fixing bolts of a motogenerator]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Guerra-Fernández]]></surname>
<given-names><![CDATA[Yamira]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ordoñez-Hernández]]></surname>
<given-names><![CDATA[Urbano]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[González-Fernández]]></surname>
<given-names><![CDATA[Vladimir]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Empresa Nacional de Mantenimiento a Centrales Eléctricas  ]]></institution>
<addr-line><![CDATA[ La Habana]]></addr-line>
<country>Cuba</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad Tecnológica de La Habana José Antonio Echeverría Facultad de Ingeniería Mecánica ]]></institution>
<addr-line><![CDATA[ La Habana]]></addr-line>
<country>Cuba</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2019</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2019</year>
</pub-date>
<volume>22</volume>
<numero>3</numero>
<fpage>156</fpage>
<lpage>160</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_arttext&amp;pid=S1815-59442019000300156&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_abstract&amp;pid=S1815-59442019000300156&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_pdf&amp;pid=S1815-59442019000300156&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen En este trabajo se han investigado las causas más probables del fallo de una parte de los pernos de fijación de 5 de las 10 zapatas polares de un generador perteneciente a un sistema motor diésel-generador de 2,5 Mw de potencia. El fallo, por sus características, ocasionó la inutilización del generador. Para investigar la causa más probable de la falla fueron seleccionados pernos que pudieron ser recuperados después de la avería y a los cuales se les realizaron análisis químico espectral, ensayos de resistencia mecánica y dureza HRc, análisis metalográfico y un análisis de las características de la fractura en los pernos dañados. Mediante el análisis de fallas mecánicas se pudo concluir que la causa primaria del fallo de los pernos de fijación de las zapatas polares del generador se debió probablemente a la pérdida de la pretensión inicial de uno o varios de los pernos, a lo cual contribuyó también la existencia de vibraciones y fuerzas electrodinámicas siempre presentes y que finalmente originaron el aflojamiento de uno o varios de los pernos de 5 de las diez zapatas polares del generador.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract In this work it was investigated the most probable causes of failure of a part of the fixing bolts of 5 of the 10 pole shoes of a generator belonging to a diesel-generator engine system of 2,5 Mw. The failure, due to its characteristics, caused the generator to be rendered useless. To investigate the most probable cause of the fault, some bolts were selected of those that could be recovered after the breakdown, and which were subjected to analysis, mechanical resistance tests and HRc hardness, metallographic analysis and an analysis of the characteristics of the fracture in the damaged bolts. Using the fracture mechanics, it was possible to conclude that the primary cause of the failure of the fixing bolts of five of the pole shoes of the generator, was probably due to the loss of the initial pretension of one or more of the bolts, to which also contributed to the existence of vibrations and electrodynamic forces that were always present and which finally caused the loosening of one or more of the bolts of five of the ten pole shoes.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[sistema electro-energético]]></kwd>
<kwd lng="es"><![CDATA[fallo de pernos]]></kwd>
<kwd lng="es"><![CDATA[zapatas polares]]></kwd>
<kwd lng="en"><![CDATA[electro-energetic system]]></kwd>
<kwd lng="en"><![CDATA[failure of bolts]]></kwd>
<kwd lng="en"><![CDATA[pole shoes]]></kwd>
</kwd-group>
</article-meta>
</front><back>
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