Bolt-Up Guideline for Pipe Flange Connections

Abstract

Numerical simulations are systematically executed for pipe flanges with wide variety of nominal size by using finite element analysis, which can simulate the bolt-up process of a pipe flange connection. Effects of the gasket modeling method on the bolt-up simulation and the bolu-up procedure which can prevent open up deformation are evaluated. It is indicated that the simplified linear modeling of gasket, in which two different Young's moduli are used in loading and unloading, is valid for estimating the variations, of mean bolt preloads during bolting up operations. The bolt-up procedure, in which four bolts located 90 degrees apart each other are tightened uniformly with the target bolt preload at the installation process, is effective to prevent the open up deformation. Finally, the methodical guideline for bolt-up operation of pipe flange connections with joint sheet gasket or spiral wound gasket is proposed.