Effect of Adhesively-Bonded Repair Patch on SIF in a SphericalPressurized Vessel

As the use of pressure vessels in various industries including oil and gas industry increases, searching for new methods to increase their life-time and to reduce the adverse effects of defects such as cracks is unavoidable.In this paper the effect of adhesively-bonded repair patches on stress intensity factor (SIF) is investigated for various geometrical parameters of semi-elliptical cracks located on inner and outer surfaces of a spherical pressure vessel. Results show that composite patch significantly reduces the SIF for both internal and external cracks. Also increasing thickness of the patch results in lower SIF values. ABAQUS software along with ZENCRACK are used to numerically model the structure and extract SIF from calculated J contour integral values. A simpler model is processed with the same approach and SIF values for this model show a good agreement with the analytical results and therefore the approached used in this paper is verified.

Keywords:

Pressure Vessel , Stress Intensity Factor , Crack , Repair Patch