Stamina of a Nongasketed Flange Joint Under Combined Internal Pressure, Axial, and Bending Loading: An Experimental Study

Abstract

Performance of a bolted flange joint is characterized mainly due to its “strength” and “sealing capability.” A number of analytical and experimental studies have been conducted to study these characteristics only under internal pressure loading. A very limited work is found in the literature under combined internal pressure and bending loading. Due to the ignorance of this external loading, i.e., bending and axial in addition to the internal pressure loading, the optimized performance of the bolted flange joint cannot be achieved. The present design codes do not address the effects of combined loading on the structural integrity and sealing ability. To investigate joint strength and sealing capability under combined loading, an extensive experimental study of a nongasketed flange joint with two different assemblies and with different load combinations is carried out, and overall joint performance and behavior is discussed. Actual joint load capacity is determined under both the design and proof test pressure with maximum additional external loading (axial and bending) that can be applied for safe joint performance. In addition, application of combined load is also discussed in the light of equivalent pressure approach.