Parametric Study of Sleeve Repair on Wrinkled Energy Pipelines

Field experience showed that repairing wrinkles developed on energy pipelines using steel sleeves is an efficient and cost effective method. Based on the previous successful numerical simulations of a field wrinkle sleeve repair work, a parametric study was conducted by using Finite Element (FE) method to further investigate the effectiveness of the sleeve repair technique. The FE package ABAQUS 6.4 was utilized in conducting the parametric study. The parameters studied include the length, the thickness, and the material properties of the sleeve, and the thickness of the collar, which is used to fit between the wrinkled pipe and the repairing sleeve. The range of the parameters studied covers the most commonly used typical values in the pipeline industry. Two phases were used in carrying out the parametric study. In Phase I, the parameter that plays the most important role in determining the behavior of the wrinkle sleeve repair system (WSRS) was studied. It is found this parameter is the length of the repairing sleeve. Brief discussion was given regarding the way this parameter affects the behavior of the pipe using the WSRS. In Phase II, based on the results from the Phase I study, the effects of other parameters were investigated through a series of FE analyses. Conclusions were drawn and recommendations for future wrinkle sleeve repair work were given based on the results of the parametric study.