STRESS DIAGNOSIS METHOD OF BENT PIPE BASED ON THE SECTION FLATNESS OF THE TANGENT PIPE SUBJECT TO BENDING

Abstract

  Experimental study was conducted to clarify the ratio of the section flatness between the tangent and the bent pipe subject to bending in a piping system with a bent pipe and tangent pipes on both ends. A finite element analysis code was also being used extensively for the calculation of stresses and section flatness in the piping.
  As a result, magnitude of the section flatness of the tangent pipe distant 0.5D from the boundary between the bent and the tangent pipe was half compared to that of the bent pipe. A method was proposed to predict the maximum stress produced in bent pipe smaller in bent angle than 90 degree based on the section flatness of tangent pipe subject to in-plane and/or out-of-plane bending.