Degree and nature of shaft misalignments in pumping units assessed against vibration criteria

Abstract

Abstract The paper shows that the degree and type of shaft misalignments, along with imbalances, have a decisive impact on vibration levels in centrifugal pumps. An accurate assessment is impossible without a unit shutdown to measure shaft alignments with special devices. A method for determining misalignments is proposed to assess the degree of misalignment against vibration spectra, the so-called rotational harmonics.