Creep Relaxation Procedure for Achieving Uniform Clamp Load Distribution in Gasketed Bolted Joints Using Simultaneous Tightening

In this paper, a mathematical procedure is developed for achieving a uniform distribution of target steady-state clamp load level in a gasketed bolted flange model, using a mass-production version of a computer-controlled simultaneous multi-spindle tightening system. Closed form solutions are developed for the required initial clamp load distribution to achieve the target clamp load using a single cycle tightening, or the number of tightening cycles required to achieve the target uniform clamp load. The effect of the gasket thickness is investigated. An experimental procedure and test set-up are used to validate the proposed gasket model. Results show reasonable correlation between the analytical model and the experimental validation data.