Advanced heavy water reactor-low enriched uranium (AHWR-LEU) is designed for high discharge burnupand large scale commercial utilization of thorium with LEU as an external feed in a once through fuelcycle. It is a 300 MWe vertical pressure tube type, thorium based reactor, cooled by boiling light water andmoderated by heavy water. The reactor incorporates a number of passive safety features and is associatedwith a fuel cycle having reduced environmental impact and offers more proliferation resistance comparedto contemporary light water reactors (LWRs). Some distinguishing features which make AHWR-LEUunique from other conventional nuclear power reactors are core heat removal by natural circulation,negative void coefficient of reactivity under all event scenarios, easily replaceable pressure tubes, longdesign life, passive safety features, etc. The long design life of the reactor is possible to be met only whenthe pressure tube which has a limited life of 15–20 full power years (FPYs) due to a life limiting mechanismcalled irradiation enhanced creep and growth is easily replaceable. Pressure tube is joined at its ends toSS 403 end fittings through rolled joints. A system has been designed and developed for detachmentof pressure tubes from the end fitting and its associated hardware without disturbing the surroundingcomponents or coolant channels so that the end fitting can be reused. The system works on the principleof shock heating and fast cooling of the pressure tube in the rolled joint region and application of axialload. Though rolled joint detachment by induction heating has been used earlier in CANDU reactors forremoval of pressure tubes and calandria tubes, the present design incorporates a liquid nitrogen basedfaster cooling arrangement and an integrated load application and gripping module for detachment andremoval of pressure tube from the end fitting in much lesser time. This paper describes the methodologyof rolled joint detachment, challenges involved in the design, features of the detachment system, findingsof experimental trials and observations.