Publications

Perforation has been used for decades to establish communication between the borehole and reservoir. There are various perforation parameters affecting the deliverability of the reservoir with penetration being one of the most important one. The initial objective in perforation was simply to provide communication between the borehole and the reservoir. In recent developments, the perforation technology evolved to address different issues and challenges, mainly focusing on productivity improvement. A well known element impairing well productivity is near wellbore damage. Near wellbore damage is a significant permeability reduction occurring around the wellbore due to drilling damage, completion damage, postproduction damage or a combination of all 3 effects. Fluid flow passing the damaged area will suffer a reduction in productivity, so it is important to mitigate the near wellbore damage or to bypass it altogether.With charge penetration getting deeper, perforation becomes an alternative to overcome the near wellbore damage and to improve productivity. To measure shape charge performance, API released guidelines on perforating charge test procedures in sections 1 to 4. The most widely recognized shape charge performance measure today is test in Section 1 where the gun system is tested against a concrete target.Penetration in the downhole condition is then predicted through mathematical modeling by taking into account various downhole conditions. There are several models available for this prediction.At the end, what matters most is how the charge performs in downhole condition. Through a series of shooting tests in real rock target with varying strength and effective stress (resembling the downhole conditions), it was found that the relation between concrete target and downhole performance is not straight forward. Certain charge performs better in downhole condition even though it performs less on a concrete target. The finding opens the idea to develop new charge optimized for downhole condition. A high energy charge is a product of this new approach, specifically designed to perform better in stressed rock.