THE TRANSMISSION OF VIBROACOUSTIC ENERGY FROM THE INDUSTRIAL MACHINES THROUGH THE BUILDING STRUCTURE TO THE MOUNTING BASE

摘要

The effective vibro-isolation of machinery reduces the transmission of vibro-acoustic energy into supporting and surrounding structures. The presented paper investigates the conditions for the transmission of dynamic loading (vibration, shock and noise) from vibrating sources, industrial machines with impact processes, transmitted through the building structure of an industrial hall and its subsequent impact on the mounting base of a laser machine used for the production of sheet metal components and on the workplace, as well. The solution of this problem requires theoretical knowledge and methodology for the measurement of the structures involved. Measurements of vibration at the sources and along the path of transmission, as well as noise measurements in the working place, were performed. The results of the vibration and noise measurements were compared before and after application of vibration isolating material to determine the effects on the machines mounting base and workplace environment. Measurements were performed also on an experimental sample to compare real results at the mounting base with experimental results on the sample under the same conditions. Sound pressure level (noise) and mechanical vibration were measured and FFT analysis was used for the detection of vibro-acoustic energy. In the first case, low-frequency vibration is analysed in the mounting base and the transmission of structurally-borne waves are investigated. Finally, the paper suggests necessary conditions and measures which may have an impact on the reduction of unwanted vibro-acoustic energy acting on the laser tool machine and its working environment.