Burst Capacity of Reinforced Thermoplastic Pipe (RTP) Under Internal Pressure

Abstract

Being corrosion resistant, light weight, and easy to install at relatively low cost, Reinforced Thermoplastic Pipe (RTP) is now increasingly being used for offshore operations. RTP pipe in this study is mainly composed of three layers: a wound high strength fiber reinforced layer to improve the resistance of the pipe to internal pressure; a plastic inner layer to transport fluid; a plastic outer layer to protect the pipe. A precise calculation of the burst strength of RTP pipe will be useful for the safe use of RTP pipe’s internal pressure resistance. The Finite Element Analysis (FEA) method and mathematical analysis are employed to study the properties of pipe under internal pressure. The Finite Element Analysis method is used to simulating the pipe under increasing internal pressure using ABAQUS. The model is established with the conventional shell element, and the anisotropic property of plastic is also considered in the model. In the mathematical analysis, the reinforcement layer of the pipe is assumed to be anisotropic and other layers are assumed to be isotropic. Based on the three-dimensional (3D) anisotropic elasticity theory, an exact elastic solution for burst strength of the pipe under internal pressure has been studied. This paper focus on the calculation of RTP pipe’s burst strength, using mathematical approach and FEA approach, on the basis of elaborated study of RTP pipe’s failure process. Our results from mathematical and FE simulation agree each other for burst pressure of the RTP pipe. Our FEA models are also compared with the experimental research in order to validate our FEA models.