Simulation Analysis of Limit Operating Specifications for Onshore Spoolable Reinforced Thermoplastic Pipes

Abstract

Spoolable reinforced plastic line pipes (RTPs), exhibiting a series of advantages such as good flexibility, few joints, long single length, light weight, easy installation, etc., have been widely used in the onshore oil and gas industry such as oil and gas gathering and transportation, high pressure alcohol injection, water injection, sewage treatment, and other fields. However, due to the lack of clear standard specificationof the limit operating properties for RTPs, three typical failure modes, i.e., tensile, flexure, and torsion, frequently occur in terrain changes,construction operation, and subsequent application, which seriously affects the promotion and use of RTPs. In this paper, the stress distribution of a non-bonded polyester fiber reinforced high-density polyethylene (HDPE) pipe (DN 150, PN 2.5 MPa) was systematically studied by the finite element method (FEM),and then the limit operating values under the axial tensile, coiled bending, and torsion load were determined.The corresponding experiments were conducted to validate the reliability and accuracy of the FEM model. The FEM results showed that the critical strain for axial tensile was 3%, the minimum respooling bend radius was 1016.286 mm, and the limit torsion angle of this RTP was 58.77°, which are very close to the experimental results. These limit values will be useful to establish normative guidelines for field construction and failure prevention of onshore RTP.

Molecular Simulation Study on the Hydrogen Permeation Behavior and Mechanism of Common Polymers

“…One of the approaches to addressing the impact of hydrogen on pipeline steel is to use non-metallic composite pipelines, such as reinforced thermoplastic composite pipes (RTPs). RTPs commonly consist of an inner thermoplastic liner, multiple fiber reinforcement layers, and an outer protective layer [11]. Thermoplastic liners absorb gases under high pressures and temperatures due to the intrinsic characteristics of polymer materials.…”

Finite-Element-Analysis-Based Study of a Failure Phenomenon in HDPE Pipes

“…The optimal size of the cables could thus be determined. Other interesting applications of FEM in the analysis of tube systems used to transport liquids have been presented in [15][16][17][18][19][20][21][22][23][24][25][26][27][28].…”