Estimation of Residual Stresses Influence on Oscillation Modes of Welded Housing Part

The article is devoted to the calculation and experimental determination of Coriolis flowmeter case vibrations modes. The case of the flowmeter is welded of thin steel plates 12H18N10T. It is determined that calculated and experimental modes of vibrations of some elements of a case free from welded joints vary by 3%. After all the elements are welded the modes of case vibration vary by over 50%. Such great variation can be explained by two reasons, i.e., influence of residual stresses after welding and case deformation due to the mentioned stresses. By means of coordinate measuring manipulator “Stinger II” highly precise surface measurement is held. Then finite-element calculation of model is performed with consideration to the real geometry of the object. To check the influence of residual stresses on case vibration modes one employs stress relieving.