The plastic instability of clamped-clamped conical thin-walled pipe reducers. (October 2016)

• Record Type: Journal Article
• Authors: Awad, Ibrahim; Saleh, Ch.A.R.; Ragab, A.R.
• Is Part Of: International journal of pressure vessels and piping. Volume 146(2016)
• Page Start: 87
• Page End: 94
• Publication Date: 2016-10
• Subjects: Plastic instability -- Limit load -- Conical shells; Pressure vessels -- Periodicals; Pipe -- Periodicals; Récipients sous pression -- Périodiques; Tuyaux -- Périodiques; Pipe; Pressure vessels; Periodicals; 681.76041
• DOI: 10.1016/j.ijpvp.2016.07.012
• Languages: English
• ISSNs: 0308-0161

Abstract

Abstract: The analytical study for plastic deformation of clamped–clamped conical reducer pipe under internal pressure does not deduce a closed form expression for the pressure at plastic instability. The presented study employs finite element analysis (FEA) to estimate the internal pressure at instability for conical reducers made of different materials and having different dimensional configurations. Forty dimensional configurations, classified as medium type, and five types of materials have been included in the analysis using ABAQUS package. A correlation expression is derived by nonlinear regression to predict the instability pressure. The proposed expression is verified for other dimensional configurations out of the above used forty models and for other materials. Experiments have been conducted by pressurizing conical clamped-clamped reducers until bursting in order to verify the finite element models. Comparison of instability pressures, strains and deflections at specific points along the conical surface shows satisfactory agreement between analysis and experiments. Highlights: This study offers a parametric study of the plastic instability pressure of clamped-clamped conical reducers. A closed form analytical expression for the instability pressure is derived by using nonlinear regression. The finite element analysis is validated by conducting bursting tests.