Effects of the Interface Configurations on the Characteristics of Bolted Joints : The Case Where the Clamped Part is a Cover of Pressure Vessel

Abstract

In designing bolted joints it is important to examine the sealing performance and to estimate the force ratio, that is the ratio of an increment of bolt axial force to a load. Up to now, in order to improve the sealing performance, raised faces of interface have been used. But the use of these interfaces depends on experience and the theoretical grounds are not made clear. In this paper, in the case where a cover of pressure vessel having a raised face is joined to the base, the contact stress of the interface is analyzed by a three-dimensional theory of elasticity and the point matching method. Furthermore, the force ratio and the maximum stress produced in bolts are analyzed. For verification experiments are performed. Analytical results are in a fairly good agreement with experimental ones. Discussion is made on the sealing performance for various interface configurations.