Fracture studies on carbon steel elbows having part-through notch with and without internal pressure. (February 2016)

• Record Type: Journal Article
• Authors: Saravanan, M.; Vishnuvardhan, S.; Gandhi, P.; Pukazhendhi, D.M.; Raghava, G.; Sahu, M.K.; Chattopadhyay, J.; Dutta, B.K.
• Is Part Of: International journal of pressure vessels and piping. Volume 138(2016)
• Page Start: 19
• Page End: 30
• Publication Date: 2016-02
• Subjects: Leak-before-break -- Crack growth -- Fracture -- Plastic collapse load -- Internal pressure; ASME American Society of Mechanical Engineers -- ASTM American Society for Testing and Materials -- BNC Bayonet Neill Concelman -- CMOD crack mouth opening displacement -- IPT image processing technique -- LBB leak-before-break -- LLD load-line displacement -- LVDT linear variable differential transducer -- MML maximum measured load -- NPP nuclear power plant -- OD outer diameter -- PCL plastic collapse load -- PCM plastic collapse moment -- PHT primary heat transport -- TPCL theoretical plastic collapse load; Pressure vessels -- Periodicals; Pipe -- Periodicals; Récipients sous pression -- Périodiques; Tuyaux -- Périodiques; Pipe; Pressure vessels; Periodicals; 681.76041
• DOI: 10.1016/j.ijpvp.2016.02.017
• Languages: English
• ISSNs: 0308-0161

Abstract

Abstract: Elbows are one type of components widely used in various industrial applications in conventional and nuclear power generating plants, chemical processing plants and petroleum refineries. Due to the complexities of geometric structure, elbows are one of the piping components that are prone to failure in the piping system of nuclear power plants (NPPs). In service, the piping components are subjected to internal pressure in addition to bending loads, and the internal pressure is known to have significant effect on the load carrying capacity of these components. Hence, fracture studies were carried out on 406 mm diameter elbows with and without internal pressure. The investigations have shown that the location of notch plays an important role in the load carrying capacity of the elbows and their failure behaviour. The internal pressure reduced the load carrying capacity of the elbow when the notch was located at the intrados in circumferential direction and the behaviour is vice-versa when the notch was located at the intrados in an axial direction, when subjected to opening moment, in both the cases. Graphical abstract: Highlights: Fracture studies were conducted on elbows with and without internal pressure. Effect of internal pressure on load carrying capacity of the elbows was studied. Ovalization of elbows under in-plane opening and closing moments was studied. Internal pressure reduced load carrying capacity of elbow with circumferential notch at intrados.