Effect of the change of Depth and Location of Transverse Cracks on Frequencies of Rotating Shaft

Abstract

In this paper, An-Non destructive test technique was used to study the change of depth and Location of transverse cracks on the vibration characteristics of the rotating shafts. Firstly, It measured the natural frequencies of the rotating shaft are measured before renewing cracks with different dimensions and depths from the bearing of the rotating shaft. And by knowing the Speed of the Shaft, Then by using (Vibration analyzer B & K type 2515) to analyze the vibrational characteristics during the rotation and compare it with mathematical analysis using the method of mounting the rotating shaft. Secondly, a crack of a certain depth and dimension away from the rotating shaft bearing was made. The measurements of the natural free vibration due to the presence of the crack were carried out. The study took into consideration the diameter and the length of the rotating shaft. The practical results showed a decrease in the natural frequencies of the rotating shaft when the crack was present. This decrease was more when the crack was located in areas near the bearing than was located away from the bearing.