At midnight, Iraq local time, on April 12, 2023, Well Ru-551 was successfully completed by ZPEC Rig 26 Team in Rumaila Oilfield, Iraq. The safety and efficiency of ZPEC’s Cementing Team in the plugging operation of Well Ru-551 was highly recognized by Party A, and provided valuable local experience for efficient plugging there.
Well Ru-551, with a designed well depth of 3,414m, is a main-pay production well drilled by ZPEC Team 26 and is located at the edge of South Rumaila. Frequent well leakage in many formations in the Rumaila Oilfield seriously restricts the drilling progress. Shuaiba leakage is extremely rare in the Rumaila Oilfield, and there are no successful experiences for reference. The adjacent well, Ru-306 drilled by IDC in 2008, is 500m away from the main well. Forty seven attempts at cement plugging were tried with a loss period as long as 101 days, resulting in huge material consumption and economic loss. Safe and efficient implementation of plugging became one of the difficulties essential to overcome.
In order to ensure the success rate of plugging, ZPEC Cementing Team discussed with ZPEC Iraq Project Department in the early stages in order to find out the geological characteristics of the block. They were able to then optimize the plugging plan and technical measures, and overcome the deep burial of the leaky layer, the high well temperature, the long open hole section, mitigate the upper Tanuma shale layer collapse risk, and other difficulties. In the case of loss-return leakage in multiple formations, only 6 cement plugs were used to plug the leakage, and all the leakage layers of the well were successfully blocked. Continuing to drill, there was no re-leakage in the inlet and no leakage in the cementing, which demonstrated the excellent technical strength and brand advantage of ZPEC Oilfield Services.
(ZPEC BP Cementing Team/Yuan Zhengtang, )