Present calculation methods dedicated to bolted flanged connections

Approved in March 2001, the European calculation standards for Bolted Flange Connections (BFC) EN 1591-1 and ENV 1591-2, developed in the framework of the Pressure Equipment Directive PED-97/23/EC-29/05/97, is an excellent alternative to the Taylor Forge method, since it provides a better knowledge of the BFC behaviour at operating conditions. Based on both leak-tightness and strength criteria, the EN1591 enables a better tightening recommendation and an improvement of the leak-tightness in view of the respect of new requirements concerning fugitive emissions limitation. In this paper, a detailed presentation of EN1591 advantages compared with the Taylor Forge method and the new alternatives rules from PVRC is given regarding the behaviour of each component of the BFC and the loads applied on the BFC.