A new methodology for the optimization of bolt tightening sequences for ring type joints. (1st January 2017) - Coria, Ibai
Abstract: Achieving uniform bolt load distribution is critical to obtain leak-free service in pressure vessel gasketed joints used in offshore pipelines. This is a difficult task due to bolt load variations during the assembly process. In this sense, the Elastic Interaction Coefficients Method has been developed in previous works to define tightening sequences that provide the target load at the end of the sequence in one or two passes. The method is very costly because a complete sequence must be simulated and the load of every bolt must be measured after each tightening operation. The present work validates this method for Ring Type Joints and further develops a numerically and experimentally validated new methodology that provides highly satisfactory results with a significantly lower cost. Highlights: Uniform bolt load distribution is necessary to avoid leakage in Ring Type Joints. Standards recommend generalist tightening sequences consisting of several passes. First, existing EICM method was validated for defining optimal one-pass sequences. Second, a new methodology was developed, which is more efficient than EICM. Third, the results of the new methodology were validated in a test bench.