<p>Offshore pipelines are widely used in oil and gas transportation. Environmental corrosion and fatigue loading inevitably lead to the growth of cracks, corrosion pits, and other defects. In the event of extremely serious defects, the entire pipe may need to be replaced. However, this is not cost-effective. Alternatively, serious defects may be addressed by reinforcing the original pipe using a B-type sleeve repair. Therefore, the effects of the heat input generated in the welding process on the original defects must be examined. This paper presents an investigation on the influence of the welding start position and the distance between the welding heat source and crack surface on the crack driving force. The crack driving force during the repairing process is compared to the fracture toughness in order to ensure the structural safety. The findings provide a foundation for determining the appropriate B-type sleeve repair process.</p>