Computation of the stress intensity factor for repaired cracks with bonded composite wrap in pipes under traction effect

Abstract

In this article, the analysis of the behavior of cracked pipeline repaired with bonded composite wrap subjected to traction effect is performed using three-dimensional finite element methods. The stress intensity factor at the crack front was used as the fracture criteria. The stress intensities at the internal and external positions of repaired crack were compared. The effects of the mechanical and geometrical properties of the adhesive layer and the composite wrap on the variation of the stress intensity factor at the crack front were analyzed. The obtained results show that the presence of the bonded composite repair reduces significantly the stress intensity factor, which can improve the life span of the pipe.

Optimization of the geometrical parameters of bonded composite wrap for repairing cracked pipelines

“…Numerical methods such as finite element method (FEM) have grown considerably in recent years. Several authors have used this method to analyze the performance of pipe repair by a composite patch [16][17][18][19][20]. The majority of these authors have used the linear mechanics of fracture approach to evaluate the reduction of stress intensity around the crack front by the composite wrap.…”

Finite element method investigation of geometrical influences of adhesive and patch in the safety for 90° elbow piping system

“…Piping systems bends at 90° are the weak zone in transport of hydrocarbons and can lead to fatigue damage. The mechanical and the geometrical characteristics of composite patch and adhesive play an essential role to repair the pipeline elbow under internal pressure, crack angle and bend angle [25][26][27][28][29]. Basically, the numerical three-dimensional method shows several results for cracked elbow and it's repaired by composite patch to increase lifetime of piping system [25][26][27][28][29].…”

“…All cracks problems of piping systems will be repaired by improving the quality of composite patch and adhesive. In order to study the effects for different mechanical and geometrical properties of the repair components with adhesive are very important where we use the SIF to analyze the pipeline repair in the elbow cracked case [25]. The finite element simulations are performed using Abaqus.…”

“…The finite element simulations are performed using Abaqus. The finite element method is used to investigate of cracked elbow of various crack angles under internal pressure and with the bending angle 90° as showed in Figure 3 [25,5]. The FE mesh for the crack is shown in Figure 3.…”

“…The elbow crack was meshed at critical zone using three-dimensional hex-dominated quadratic elements. For improving the SIF data, the elbow is able to be used where the simulation on crack zone is carried out using the 20-node brick elements with mesh refinement near the crack tip [20][21][22][23][24][25]. For precision, mainly the mesh in the crack front was refined in the elbow crack to simulate the stress intensity factor [25][26][27][28][29][30].…”