Stress distribution analysis of composite repair with Carbon Nanotubes reinforced putty for damaged steel pipeline. (1st December 2021)

• Record Type: Journal Article
• Authors: Arifin, Hanis Hazirah; Zardasti, Libriati; Lim, Kar Sing; Md. Noor, Norhazilan; Yahaya, Nordin; Mazlan, Ain Naadia; Mohd. Sam, Abdul Rahman
• Is Part Of: International journal of pressure vessels and piping. Volume 194:Part A(2021)
• Publication Date: 2021-12-01
• Subjects: Load-transfer mechanism -- Reinforced putty -- Carbon nanotubes -- Finite element analysis -- Repaired pipeline -- Burst failure; Pressure vessels -- Periodicals; Pipe -- Periodicals; Récipients sous pression -- Périodiques; Tuyaux -- Périodiques; Pipe; Pressure vessels; Periodicals; 681.76041
• DOI: 10.1016/j.ijpvp.2021.104537
• Languages: English
• ISSNs: 0308-0161

Abstract

Abstract: Composite pipeline repair systems involving infill material and composite wrapper are a common method of enhancing the integrity of damaged oil and gas pipelines. Composite wrappers can be theoretically optimised by minimising the layers of wrapper whilst reinforcing the infill material; i.e., putty. Integrating nanomaterial into putty to enhance its strength is a novel approach to provide secondary layer protection of damaged pipelines. A finite element model simulating a composite repaired pipe was developed to investigate the influence of reinforced Carbon Nanotubes putty on the system's overall repair performance and behaviour. The result was verified with a previous experimental hydrostatic burst pressure test and industrial standard resulting in less than a 15% error margin. The result shows the damaged artificial pipe segment filled with two different putties, namely Grout A and Grout B, ruptured at 32.22 MPa and 32.93 MPa, respectively. The reinforced putty improved the load-bearing capacity of the repaired pipe by a marginal increment of 2.2%. It demonstrated a better load-transfer and load-sharing mechanism than the common composite repair system. The recorded burst failure of the repaired pipe was less abrupt, thus minimising the sudden rupture of the pipeline by acting as a secondary layer of protection in the event of a composite wrapper failure. Highlights: Main discovery was associated with the behaviour of the repaired pipe. CNTs reinforced putty is capable of minimising the sudden rupture of repaired pipe. Putty is subjected to relatively high tensile stress compared to compressive stress. Findings from this study can spark more interest in this particular area.