Análise de motobombas submersas com diferentes acionamentos elétricos a partir da Roda de Falhas

Abstract

Avoiding failures is an extremely necessary measure when managing water production and distribution systems with 95% of networks pressurized directly by wells. Based on the frequent water shortages in 2015, registered by CAERN at the Parnamirim Water Operation and Maintenance Unit (UNAP), the most notable are the damages caused by overheating and other mechanical and electrical damages that lead to failures in the motor pump Submerged. In this scope, this work was carried out to carry out a case study on the installations of four well pumps PC, PD, PS and PI, with different electric drives, using the Failure wheel proposal in an electric predictive analysis And thermographic, to qualitatively infer about the level of reliability and cost of maintenance in the water supply concessionaire. In order to subsidize the analyzes, important items of the aforementioned facilities were inspected, observing their relations of conformity with the specifications of the pumps, where electrical and thermal parameters of operation were carried out, including stress variables to aid in the diagnosis and to estimate the performances of these machines. The analysis was carried out by a checklist of operational parameters, checklist and by Failure Wheel in discussion, which allowed for diagnoses on inspection data and the history of recurring faults. In this sense, the application of the Failure Wheel occurred with the adaptation of a model for the submersible pumps, identifying the main damage mechanisms associated to the general causes of failures, which demonstrated viability in maintenance routines based on the condition for detective-predictive analysis of faults in the equipment. Comparing the specific energy consumption between the pumps, the PI, with drive by frequency inverter, obtained better efficiency, offering greater energy efficiency during the water harvest between July 2015 and July 2016. It showed a reduced risk of failure Typical of motor pumps, among the equipment, considering the lower thermal level in operation presented in thermographs, and the lower stress caused due to the characteristics of the starter. It was concluded, therefore, that its reliability level was the highest, followed by PS, PC and PD. The advantages of the systematic application of the proposal, coupled with a planned maintenance policy, point to the reduction of intercurrences due to failures and losses of production, and with this, allow to reduce premature equipment changes and costs with maintenance and electric energy. As a result of the research, a methodology of predictive monitoring was obtained, aiming at maintenance actions before the catastrophic failure on items in the course of damages.