Offshore interventions and workovers are one of the most expensive operations in the oil and gas industry that's imposing high budget assignments and operational complexity with related risks to operating companies. In addition to that, the related logistics become more challenging and costly. Mature fields with offshore platforms in Gulf of Suez in Red Sea has limited capabilities of cranes and logistics that enables rig less intervention and required rig assistance for workover these well. Many wells are being shut-in due to scale accumulations, increased skin values and water production problems that needs the intervention to regain well accessibility and enable oil production.

This case study is for 9 wells on 3 different platforms in Gulf of Suez in Red Sea in Egypt that are producing from different reservoirs. Several sensitivity and lab analyses were performed to ensure the full compatibility and feasibility to perform such operation within the limited space areas without jeopardizing the operational excellence or safety. Those fields are part of the mature fields producing for more than 20 years. Many challenges are existing within those fields including water production problems and various scale accumulations that ceased production from these wells. Additionally, most of the platforms doesn't contain cranes with highly deviated wells and sour environments. Diagnostics were performed to either identify the water entry points or performing perforations. However, wells’ accessibility must be obtained. To overcome these challenges, a customized Coiled Tubing (CT) intervention solution was utilized with a stackable track-stack to enable the intervention and perform either cleanout with jetting or milling or stimulations to regain wells accessibility and productivity. Simulations of these interventions were critical to conduct the operations safely.

Several downhole applications were introduced along with the new customized rig up solution for CT over these platforms in order to overcome the different challenges of high deviation with sour and heavy oil production from some wells. Other supporting utilities for the high-pressure pumping were introduced utilizing supplying vessels to optimize the operating costs. The customized solution enabled the restoration of wells accessibility. Additionally, potential related problems of time, operational risks and costs were reduced compared to rig workover costs in such offshore environment. First implementation to this solution was carefully planned to cover all potential contingencies during the intervention due to its criticality and being the first implemented intervention in Gulf of Suez combining the existing downhole challenges with limited platforms capabilities.

Customized workover and intervention have brought new insights and lessons learned for such a novel operation that enabled the full wellbore accessibility to more than 9 wells with additional oil production of more than additional ten thousand bbls of oil production compared to zero production and shut in status for wells within this study. The success and novels captured indicate several opportunities for operating companies to push the limits for solving offshore intervention challenges with big cost savings related to offshore rigs in shallow waters fields.

You can access this article if you purchase or spend a download.