Behaviour of brazed pipe flanges with separate clamping rings

Abstract

Three pairs of aluminium-brass 100-mm-bore flange models with different surface finishes of the joint faces have been subjected to known bolting forces and internal pressures up to seven times the rated pressure at room temperature. Hard and soft flat gaskets were used and it was found that the joint efficiency was independent of gasket material, surface finish, and initial bolt tension. Surface strains on the outer surfaces of the tubes and flange rings were measured with electrical-resistance strain gauges where these could be fitted. These results are also presented. The flanges did not fail; tests ended when the loose steel rings touched owing to excessive deformation, so that the gaskets were prevented from sealing.