Design analysis of inverted L-shaped main steam pipeline whipping protection

  Objectives  The purpose of this paper is to solve the main steam pipeline whipping protection problem from a ship's steam generator(SG) to the cabin wall.

  Methods  Therefore, a finite element model of the inverted L-shaped pipeline and U-bolts is established using LS-DYNA software to simulate the collision dynamic process. Under two layout schemes, the stress-strain distribution and restraint rejection force time history curves of the U-bolts are analyzed.

  Results  In collisions caused by the imaginary welding seam break of the SG oblique steam exit, the horizontal pipeline displacement is even greater than the vertical, requiring the installation of another group of U-bolts to restrain lateral pipeline movement. With regard to such limiting factors as cabin spatial dimensions and seam break collision protection for the right-angle elbow at both ends, one set of 45-degree obliquely installed U-bolts located at the inverted L-shaped pipeline elbow can replace two sets of horizontally and vertically installed U-bolts.

  Conclusions  The results of this study can have guiding significance for the whipping protection design of the main nuclear power steam pipelines of ships.