Thesis EVALUACIÓN, DIAGNÓSTICO Y SOLUCIÓN A PROBLEMA DE VIBRACIONES EN EL DUCTO DE DESCARGA DE LAS BOMBAS DE RECUPERACIÓN DE AGUA INDUSTRIAL DE UNA PLANTA PROCESADORA DE RELAVES
Date
2015
Authors
ALBAYAY RUVIÑO, FRANCISCO EDUARDO
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
La puesta en marcha del tercer espesador de una planta procesadora de relaves de mineral de cobre en Chile, generó un aumento del 50% en la capacidad de agua recuperada, de 3 000 m3/h (833 l/s) a 4 500 m3/h (1 250 l/s). Para generar la impulsión de esta agua a la planta se construyó una nueva sala de bombas que aumentó a 8 unidades las 5 existentes anteriormente para dicha labor. Durante la puesta en marcha de las 3 nuevas unidades, se detectaron problemas de vibraciones excesivas que podían estar relacionados con 3 fallas ocurridas en las mismas bombas (un corte de eje y dos roturas de machón de acoplamiento), ante la aparición de estas vibraciones se arriesgaba el colapso del piping de las bombas y la posterior inundación del sector (hecho que había ocurrido con anterioridad en la sala 1 por el colapso de una válvula). Por lo que se optaba por dejar fuera de operación los equipos que presentaban altos niveles de vibración, generando mermas en la recuperación de agua de la planta y a raíz de esto, pérdidas de producción de concentrados. Para dar solución al problema, el suscrito desarrolló una investigación especial para determinar las causas de las vibraciones presentes en el ducto. Se realizaron mediciones y análisis de vibraciones para diferentes configuraciones de flujo, se realizó un ensayo de respuesta en frecuencia ante excitación tipo impacto y se modeló en software FEM el ducto de descarga de las bombas para la determinación de sus frecuencias naturales de manera de descartar resonancias estructurales. Se identificó que el origen de las vibraciones es producido por la obstrucción con materiales extraños en la bomba, específicamente el rodete y la cámara de succión. Se generó una metodología de inspección periódica, en base al análisis de vibraciones, para programar eventuales limpiezas en los componentes de las bombas. El resultado del trabajo desarrollado fue disminuir los niveles de vibración hasta un 89% respecto a la condición inicial y junto con ello, alcanzar la operación normal de la planta de manera continua en el tiempo.
Commissioning of the third thickener in a copper mineral tailings processing plant in Chile, generated a 50% increase in recovered water capacity from 3 000 m3/h (833 l/s) to 4 500 m3/h (1 250 l/s). To pump the water to the plant, a new pump-house was built which increased to 8 units above 5 existing for this work. During the launch of the 3 new units, problems of high vibrations levels were detected, that could be related to three failures occurred in the same pumps (one cut-axis and two breaks the coupling) with the appearance of these vibrations it was risked the collapse of the piping of pumps and subsequent flooding in the sector (a fact that had occurred earlier in the room 1 by the collapse of a valve) So they decided turn out of service equipment with high levels of vibration, causing decline in water recovery plant and because of this, concentrate production losses. To solve the problem, the autor developed a special investigation to determine the main cause of the vibrations present in the piping. Vibration measurements and analysis for different flow configurations were performed, frequency response to impact excitation test was performed and also modeling the piping in FEM software for naturals frequencies determinations, in order to rule out structural resonances. It was identified that the source of vibration is produced by foreign material clogging the pump, impeller and suction chamber specifically. Periodic inspection methodology was generated, based on vibration analysis, for programming at eventual cleaning pump components. As a result of work developed, it was possible to reduce vibration levels up to 89% and together with it reach normal operation of the plant continuously over time.
Commissioning of the third thickener in a copper mineral tailings processing plant in Chile, generated a 50% increase in recovered water capacity from 3 000 m3/h (833 l/s) to 4 500 m3/h (1 250 l/s). To pump the water to the plant, a new pump-house was built which increased to 8 units above 5 existing for this work. During the launch of the 3 new units, problems of high vibrations levels were detected, that could be related to three failures occurred in the same pumps (one cut-axis and two breaks the coupling) with the appearance of these vibrations it was risked the collapse of the piping of pumps and subsequent flooding in the sector (a fact that had occurred earlier in the room 1 by the collapse of a valve) So they decided turn out of service equipment with high levels of vibration, causing decline in water recovery plant and because of this, concentrate production losses. To solve the problem, the autor developed a special investigation to determine the main cause of the vibrations present in the piping. Vibration measurements and analysis for different flow configurations were performed, frequency response to impact excitation test was performed and also modeling the piping in FEM software for naturals frequencies determinations, in order to rule out structural resonances. It was identified that the source of vibration is produced by foreign material clogging the pump, impeller and suction chamber specifically. Periodic inspection methodology was generated, based on vibration analysis, for programming at eventual cleaning pump components. As a result of work developed, it was possible to reduce vibration levels up to 89% and together with it reach normal operation of the plant continuously over time.
Description
Catalogado desde la version PDF de la tesis.
Keywords
BOMBAS CARCASA PARTIDA AXIALMENTE , PLANTA DE RECUPERACION DE AGUA , VIBRACION DE PIPING , VIBRACIONES MECANICAS