Rotating Machines Energy Loss Due to Unbalance

Abstract

Unbalance is one of the most common defects in rotating machinery that causes important vibrations and subsequently an increase in energy consumption. Unbalance is defined as un-equal distribution of weight around the center of rotation. Although vibration, heat and noise are usually the results of mechanical defects, vibrations present the most relevant indicator for the identification of unbalanced shaft. By monitoring time indicators such as the Root Mean Square (RMS), unbalance is detected. This paper aims to experimentally analyze the energy losses due to shaft unbalance. The proposed methodology is meant to emphasise on the relationships between vibration level and energy consumption for different degree unbalance defect. A laboratory test rig was designed to create unbalance by adding weights at various eccentricities. For each case, RMS indicator and the electrical characteristics were measured. The results obtained from this study show that vibration analysis is an effective technique to identify unbalance severity and energy losses.