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Catcher bearing life prediction using a rainflow counting approach / Jung Gu Lee in Transactions of the ASME . Journal of tribology, Vol. 134 N° 3 (Juillet 2012) 

Public ISBD [article]  in Transactions of the ASME . Journal of tribology > Vol. 134 N° 3 (Juillet 2012) . - 15 p. Titre : Catcher bearing life prediction using a rainflow counting approach Type de document : texte imprimé Auteurs : Jung Gu Lee, Auteur ; Palazzolo, Alan, Auteur Année de publication : 2012 Article en page(s) : 15 p. Note générale : tribology Langues : Anglais (eng) Mots-clés : rotating  machine;  Catcher  bearings;  fatigue  life;  rainflow  counting  algorithm Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Catcher bearings (CB) are an essential component for rotating machine with active magnetic bearings (AMBs) suspensions. The CB's role is to protect the magnetic bearing and other close clearance component in the event of an AMB failure. The contact load, the Hertzian stress, and the sub/surface shear stress between rotor, races, and balls are calculated, using a nonlinear ball bearing model with thermal growth, during the rotor drop event. Fatigue life of the CB in terms of the number of drop occurrences prior to failure is calculated by applying the Rainflow Counting Algorithm to the sub/surface shear stress-time history. Numerical simulations including high fidelity bearing models and a Timoshenko beam finite element rotor model show that CB life is dramatically reduced when high-speed backward whirl occurs. The life of the CB is seen to be extended by reducing the CB clearances, by applying static side-loads to the rotor during the drop occurrence, by reducing the drop speed, by reducing the support stiffness and increasing the support damping and by reducing the rotor (journal)—bearing contact friction. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013400 [...] [article] Catcher bearing life prediction using a rainflow counting approach [texte imprimé] / Jung Gu Lee, Auteur ; Palazzolo, Alan, Auteur . - 2012 . - 15 p. tribology Langues : Anglais (eng) in Transactions of the ASME . Journal of tribology > Vol. 134 N° 3 (Juillet 2012) . - 15 p. Mots-clés : rotating  machine;  Catcher  bearings;  fatigue  life;  rainflow  counting  algorithm Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Catcher bearings (CB) are an essential component for rotating machine with active magnetic bearings (AMBs) suspensions. The CB's role is to protect the magnetic bearing and other close clearance component in the event of an AMB failure. The contact load, the Hertzian stress, and the sub/surface shear stress between rotor, races, and balls are calculated, using a nonlinear ball bearing model with thermal growth, during the rotor drop event. Fatigue life of the CB in terms of the number of drop occurrences prior to failure is calculated by applying the Rainflow Counting Algorithm to the sub/surface shear stress-time history. Numerical simulations including high fidelity bearing models and a Timoshenko beam finite element rotor model show that CB life is dramatically reduced when high-speed backward whirl occurs. The life of the CB is seen to be extended by reducing the CB clearances, by applying static side-loads to the rotor during the drop occurrence, by reducing the drop speed, by reducing the support stiffness and increasing the support damping and by reducing the rotor (journal)—bearing contact friction. DEWEY : 621.5 ISSN : 0742-4787 En ligne : http://www.asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JOTRE900013400 [...]