Inadequate productivity of perforated wells has been a major concern since the introduction of cased completions. Petrobel company, operating in the Belayim fields of Sinai, Egypt, and responding to an unpredictably fast decline in field production, launched an initiative in 1996 to identify the under-performing perforated wells in order to plan remedial actions. Since the vast majority of the wells were under artificial lift, this involved the integration of data from various sources. The study revealed that the majority of wells in the field were in fact suffering from excessive damage. Wells were then categorized based on the value of their completion factors (the ratio of actual to theoretical productivity indices), and the potential sources of damage were identified for each category. This was accomplished using techniques such as nodal analysis and skin modeling.

One of the most successful techniques used to cure the damage was the re-perforation of the damaged wells with deep-penetrating perforating charges. Until the use of this technique, and even with attempted improvements in other operating parameters, field performance had continued to fall short of theoretically predicted results. This paper highlights the origin and development of formation damage in the Belayim fields, and how this damage was attributed to different damage mechanisms using a novel combination of nodal and damage analysis techniques. It also presents some cases of dramatic productivity enhancement due to the use of these techniques and the introduction of deep penetrating perforating.

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