Análise do desgaste em mancais radiais de motores usando instrumentação de baixo custo

Abstract

The use of pumps installed in artesian wells for underground water extraction is a technique widely used in Brazil, especially in the Northeast, in places where drought is predominant during the year. In some regions, this extraction accounts for 70% of the population's water supply. Studies show that 50% of failures in electric motors start at the bearings and these represent only 30% of the total value of corrective maintenance. The present work carried out a study on the radial bearings of the motors used in artesian wells. A low cost Arduino data acquisition system and MPU6050 sensor for capturing system vibration signals have been developed. The sensor was positioned close to the radial bearing. Four different bearing situations were analyzed. The first, with factory setting of 0.1 mm clearance between the shaft and bushing in the bearing, the second, third and fourth operating conditions were 0.2, 0.5 and 1.0 mm time off respectively. For each situation, the test was repeated six times for three minutes each. The data obtained in Arduino were studied through time and frequency domain analysis. For each operating condition it was possible to identify an operating pattern. Based on this, a diagnostic methodology for the study target engine was developed and put to the test in a case study.