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

Abstract

[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.

Keywords

• steam generator
• marine nuclear power
• whipping protection
• ls-dyna
• u-bolts