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Abstract(s)
Os rolamentos de esferas sĆ£o um elemento crucial na constituiĆ§Ć£o de equipamentos com caracterĆsticas rotativas vastamente utilizados nas diferentes indĆŗstrias civis e militares. Como qualquer outro equipamento mecĆ¢nico, sofre o desgaste inerente ao seu funcionamento que sem a manutenĆ§Ć£o adequada pode originar danos nos seus constituintes, comprometendo assim o correto funcionamento ou mesmo danificar a mĆ”quina na qual estĆ” montado.
A presente dissertaĆ§Ć£o assume como objetivos principais o estudo, anĆ”lise, deteĆ§Ć£o e diagnĆ³stico de falhas em rolamentos por meio de sinais vibratĆ³rios adquiridos computacionalmente e a partir de uma bancada experimental de simulaĆ§Ć£o de falhas concebida pelo autor.
Inicialmente Ć© recolhido material para se efetuar uma abordagem teĆ³rica no Ć¢mbito dos rolamentos radias de uma carreira de esferas, identificando os componentes que o constituem assim como as suas funƧƵes e aplicabilidade nas diferentes indĆŗstrias e para a marinha. SĆ£o expostos vĆ”rios exemplos dos danos que mais frequentemente surgem durante o funcionamento dos rolamentos e de que forma se consegue detetar de forma precoce atravĆ©s dos parĆ¢metros do fator de crista e nĆvel global e diagnosticĆ” los por meio de tĆ©cnicas que envolvem a modelaĆ§Ć£o em amplitude do sinal vibratĆ³rio, como a tĆ©cnica da envolvente e transformada de Hilbert.
Os diagnĆ³sticos obtidos para a leitura dos vĆ”rios ensaios realizados na bancada experimental com rolamentos com danos nas respetivas pistas foram bem conseguidos sendo evidente a presenƧa das suas frequĆŖncias de falha.
A partir deste documento surgem novas oportunidades de estudo cientĆfico, utilizando a bancada experimental de simulaĆ§Ć£o de danos Ć© possĆvel diagnosticar falhas de outras naturezas ou estudar a influĆŖncia de cargas e variaƧƵes de velocidade em rolamentos danificados.
Ball bearings are a crucial element in the construction of rotating equipment that is widely used in various civil and military industries. Like any other piece of mechanical equipment, it suffers the wear and tear inherent to its operation which, without proper maintenance, can lead to damage to its components, thus compromising correct operation or even damaging the machine on which it is mounted. The main objectives of this dissertation are to study, analyze, detect and diagnose faults in bearings using vibration signals acquired computationally and from an experimental fault simulation workbench designed by the author. Initially, material was gathered to provide a theoretical approach to single row radial ball bearings, identifying the components that constitute them as well as their functions and applicability in different industries and for the navy. Several examples are given of the damage that most frequently occurs during bearing operation and how it can be detected at an early stage using the crest factor and global level parameters and diagnosing it using techniques that involve amplitude modeling of the vibration signal, such as the envelope technique and the Hilbert transform. The diagnoses obtained from the reading of the various tests carried out on the experimental workbench with bearings with damage to their raceways were successful, and the presence of their failure frequencies was evident. This document opens new opportunities for scientific study. Using the experimental damage simulation workbench, it is possible to diagnose faults of other kinds or study the influence of loads and speed variations on damaged bearings.
Ball bearings are a crucial element in the construction of rotating equipment that is widely used in various civil and military industries. Like any other piece of mechanical equipment, it suffers the wear and tear inherent to its operation which, without proper maintenance, can lead to damage to its components, thus compromising correct operation or even damaging the machine on which it is mounted. The main objectives of this dissertation are to study, analyze, detect and diagnose faults in bearings using vibration signals acquired computationally and from an experimental fault simulation workbench designed by the author. Initially, material was gathered to provide a theoretical approach to single row radial ball bearings, identifying the components that constitute them as well as their functions and applicability in different industries and for the navy. Several examples are given of the damage that most frequently occurs during bearing operation and how it can be detected at an early stage using the crest factor and global level parameters and diagnosing it using techniques that involve amplitude modeling of the vibration signal, such as the envelope technique and the Hilbert transform. The diagnoses obtained from the reading of the various tests carried out on the experimental workbench with bearings with damage to their raceways were successful, and the presence of their failure frequencies was evident. This document opens new opportunities for scientific study. Using the experimental damage simulation workbench, it is possible to diagnose faults of other kinds or study the influence of loads and speed variations on damaged bearings.
Description
Keywords
Rolamentos de esferas MĆ”quinas rotativas DiagnĆ³stico DeteĆ§Ć£o Dano Envelope Hilbert