On the Characteristics of Bolted Joints with Tap Bolts : The Case Where Clamped Parts are Hollow Cylinders with a Full-Face Metallic Gasket

Abstract

In designing bolted joints, it is important to know the contact stress and the force ratio (the ratio of an increment of the bolt axial force to an external load). Up to now, some investigations have been carried out on the characteristics of bolted joints with gaskets. However, the compressive spring constants K_cg of the bolted joint in which a clamped part is fastened to a base with a tap bolt including a gasket have not been studied. In the present paper, the characteristics of the bolted joint with a full-face metallic gasket are examined. Replacing a clamped part, a gasket and a base with finite hollow cylinders, respectively, the contact stress distribution, the force ratio and the compressive spring constants are analyzed using a three-dimensional theory of elasticity. In the experiments, the force ratio is measured and the contact stress is measured by an ultrasonic wave. Analytical results are in fairly good agreement with experimental results. In addition, a simple calculation method to obtain K_cg is proposed.