Case Study: Offshore Sakhalin Operating Company frees stuck BHA and saves USD 9 million with SLB Hydra-Jar AP and Accelerator AP

Impact System Frees Stuck BHA in 7 Attempts After 6 Days Stuck Downhole

Offshore Sakhalin Operating Company was performing extended-reach drilling offshore Sakhalin when its drillstring twisted off and the bottomhole assembly became stuck at 8,011 m MD. After more than 100 unsuccessful jarring attempts, the company faced the risk of losing the BHA in hole and having to recover or even redrill a 5,000-m section. SLB was brought in to help free the stuck assembly.

SLB recommended running the Hydra-Jar AP double-acting hydraulic drilling jar with the Accelerator AP impact tool to deliver higher, controlled impact forces. The system freed the drillstring in 7 attempts after 6 days stuck downhole, recovered the BHA, and allowed drilling to resume without redrilling the section. SLB’s solution delivered up to 1,000,000 lbf of impact, increased impact force by 60%, and helped the operator avoid about USD 9 million in rig time and operating costs.