Gearboxes are widely used to transmit power in concrete mixers. One of the most common aspects of concrete mixers design regards gear reduction unit, because many major faults can be classified into shaft and tooth-fatigue cracks due to cyclic loading in different process phases. Experimental simulations are expensive and accidents are hardly reproducible. Therefore, the ability for early detection, diagnosis, and prognosis of gear tooth-fatigue cracks has been one of the major technical challenges for safe and cost-effective operation of concrete mixers. In order to predict useful life of concrete mixers, we can use, together with a proposed model-based method, a test rig able to simulate any condition of work (even improper ones) and equally capable to stress the gear reduction unit. The combination between test rig and application of model represents a powerful instrument for designers and its level of development can be indifferently applied to any kind of concrete mixers. The prediction of useful life is confirmed by comparison with data obtained by costumers on building yards. The examined concrete mixer is a vertical one with planetary rotation working, three rotating mixing arms and fixed tank. The mixer has a circular tank that is protected by casing to prevent escape of dust.
Model-based method predicting useful life of concrete mixers
VALIGI, Maria Cristina;
2005
Abstract
Gearboxes are widely used to transmit power in concrete mixers. One of the most common aspects of concrete mixers design regards gear reduction unit, because many major faults can be classified into shaft and tooth-fatigue cracks due to cyclic loading in different process phases. Experimental simulations are expensive and accidents are hardly reproducible. Therefore, the ability for early detection, diagnosis, and prognosis of gear tooth-fatigue cracks has been one of the major technical challenges for safe and cost-effective operation of concrete mixers. In order to predict useful life of concrete mixers, we can use, together with a proposed model-based method, a test rig able to simulate any condition of work (even improper ones) and equally capable to stress the gear reduction unit. The combination between test rig and application of model represents a powerful instrument for designers and its level of development can be indifferently applied to any kind of concrete mixers. The prediction of useful life is confirmed by comparison with data obtained by costumers on building yards. The examined concrete mixer is a vertical one with planetary rotation working, three rotating mixing arms and fixed tank. The mixer has a circular tank that is protected by casing to prevent escape of dust.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
