Elastic-plastic analysis of a full-size elbow - Experimental and numerical investigations

Within piping systems, the parts which display the highest flexibility are the pipe bends. In normal operation, the bends are designed on one hand to change the direction of the piping run, while on the other to dissipate reaction forces and moments within the system by elastic deformation, a function to which they are well suited by their greater flexibility as opposed to adjoining straight sections of piping. Because of their specific deformation behaviour when exposed beyond the elastic limit, pipe bends are capable of plasticizing over large areas, thus considerably cushioning transiently loaded systems by energy dissipation as the result of plastic material flow. In this context, considerable importance is assigned to knowledge of the safety margin between incipient local yield and the load at which the pipe bend collapses.