In alignment with the corporate road map, the Southern Area Gas Producing Facilities (SAGPF) of Saudi Aramco has led an initiative of replacing a traditional carbon steel flow-line with reinforced thermoplastic pipe (RTP) on a trial basis. The candidate flow-line was selected after identifying several metal loss indications via an in-line-Inspection tool. The objective of this experimental pilot was to examine the performance of nonmetallic pipeline for a conventional gas well. It is noteworthy that this trial-test is considered to be the first of its kind in Saudi Aramco —the use of RTP in a permanent flow-line installation at a conventional gas well. This technical paper will primarily discuss several important elements of the project. Firstly, it will highlight an overview on the overall corrosion damage mechanism within the conventional gas wells’ piping network and existing controlling measures. Secondly, it will highlight the advantages of this technology deployment in the oil and gas industry. Additionally, it will discuss the implementation of RTP flow-line installation, in which it will present the construction phase, commissioning, operational performance, and the successful criteria of this trial test.
Composite repairs have been applied to pipelines and piping systems for structural reinforcement after external corrosion. Such repairs may consist of glass or carbon fibers embedded in a matrix of epoxy. Typically, these repairs are hand applied using either wet lay-up systems or prefabricated rolls of composite sleeve. In some applications, pipeline continued corrosion growth under composite repairs were reported using Inline Inspection (ILI) which raises a concern about the integrity of the metallic piping under composite repairs. When continued corrosion is detected by ILI, a difficulty is typically faced due to the inability to measure pipeline remaining thickness under such repairs. To resolve this challenge, this paper will discuss multiple inspection and corrosion monitoring techniques for metal loss under composite repairs. To measure the pipeline wall thickness due to internal corrosion, one or more of the three (3) Non-Destructive Testing (NDT) technologies namely; Dynamic Response Spectroscopy (DRS), Multi-skip Ultrasonic (MS-UT) and digital radiography were evaluated and found capable. To monitor for external corrosion, a scheduled visual inspection of the composite repair would be the first inspection step. If the composite repair appears to be intact then the visual inspection would suffice and the repair should be acceptable to its design life. If the original defect is external corrosion and a scheduled visual inspection of the composite repair shows damage to the composite repair then inspection to assess the integrity of the substrate must be used before permanently fixing the composite repair. For this scenario, digital radiography or MS-UT are recommended to assess the condition of the substrate