Investigation of performances of adhesives in izotropic pipes repaired different adhesives

Cracks are formed on the inner and outer surfaces of the pipes, which are affected by manufacturing defects and external loads in pipes used in oil, natural gas and plumbing systems. These cracks grow as a result of changes in temperature and pressure, causing damage to the pipe after a certain period of time. The repair and renovation of the damaged pipeline requires considerable cost, time and workmanship. Adhesive connections are now widely used in all areas of the industry for repair and assembly purposes. Due to the advantages such as lightness, vibration isolation and corrosion resistance in the repair of pipe damages, repairs are made using adhesives. The purpose of this work is to compare the performances of epoxy-based DP410 and acrylic-based DP810 adhesives in repairing damaged steel pipes exposed to internal pressures and to determine the length of overlap with appropriate patch angles. For this purpose, galvanized steel pipes with an outside diameter of 33.7 mm and internal diameter of 26.9 mm were handled and cracks were formed on these pipes by opening a channel of 17 mm length and 2 mm width. The cracks formed in the pipelines were repaired by forming a 0.2 mm thick adhesive layer using steel patches of lengths of 30, 40, 50 mm at 90°, 120°, 150° opening. Damaged values were determined by applying internal pressure to the repaired pipes. In this thesis study, ANSYS 15 package program was used for modeling and numerical solutions of pipes repaired with both adhesives. Internal pressure was applied to the generated models and numerically analyzed. The numerical results obtained were compared with the experimental results.