抄録
In these environmentally sensitive times, bolted flanged joint design that makes the leakage from a joint a design criterion has been investigating. However, achieving uniform bolt preload is difficult when tightening pipe flanges with a number of bolts, even if the appropriate amounts of bolt preload can be calculated following established design rules. A guideline for bolted flange joint assembly has been presented by ASME. However, the guideline needs repeated bolt-up operations to get uniform preloads. In this study, in order to establish a more effective bolt assembly guideline, numerical calculations are systematically executed by using three-dimensional finite element analysis. The analytical objects are pipe flanges of class 150lb and 300lb raised face slip-on welding type specified in JPI with a compressed asbestos sheet gasket inserted. The variations of bolt preload and contact pressure distributions at the gasket bearing surface during bolting up are estimated.
