Breaking Barriers: Gas Lift Valve Change-Out Challenges in a Niger Delta Field

Abstract This paper details a resilient and innovative approach demonstrated to overcome a unique challenge encountered during a gas lift valve change-out campaign in an oil field in the Niger Delta. The challenge involved gas lift valves parting into two pieces during retrieval, leaving a portion stuck in the gas lift mandrel. While some partings were clean separations at the joints, others were rough, occurring within the valve body rather than at the joints. This issue is suspected to have resulted from prolonged use before retrieval, compounded by the effects of sand production. Some valves had not been changed for over ten years, deviating from the good oilfield practice of a two-year cycle. The extensive jarring required for retrieval caused the valves to break, and leaving the parted pieces in the mandrel was not an option, as this would lead to sub-optimal lifting performance due to the multi-pointing effect. To salvage this situation, a non-standard spear tool was designed, fabricated, and deployed on one of the affected wells. The tool performed seamlessly, and the operation was successfully replicated on six additional wells, achieving similar results in five cases. The sole exception involved a valve with severe internal corrosion, as observed in the retrieved piece. This intervention saved the company approximately one thousand barrels of oil production per day, along with the associated revenue that would have been lost due to sub-optimal well performance. This drives home the importance of complying with good oil field practice stipulations, but, most importantly, taking the initiative to innovate to overcome challenges faced in the industry during well intervention operations.