Perforations-reduced connectivity to the producing formation is an ongoing industry challenge. Whether it is caused by high debris or formation compaction, this reduction can be as high as 90%. Several methods were developed to overcome the reduction. Methods such as dynamic underbalance and acidizing bypass damage by using propellants or employing new process such as hydraulic fracturing.

Dynamic underbalance is an effective method to stimulate productivity when it is accurately applied using the right conditions at the initial perforation event. Some wells, however, face reduced productivity because of plugging in the existing perforations.

The case presented in this study examines the application of dynamic underbalance in a well that was treated by generating a surge at the level of the perforations, without resorting to elaborate and costly operations of re-perforating the zone, acidizing or using propellants. The technique was applied in a single wireline run which led to restored connectivity and yielded quadruple the rate of productivity.

This paper emphasizes the need for pre-job modelling to avoid unnecessary operations, presents the associated sensitivity analysis, the deployment methodology and the sequence of operations, as well as the operational advantages over other cleanup methods. Additionally, it assesses the conditions that make a well a good candidate for dynamic underbalance while reducing complex logistics and mitigating the risks of failure. Finally, it presents the results of the operation and increased productivity.

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