Cementing Through PBL Bypass System with BHA in Place

ABSTRACT Encountering severe mud losses while drilling oil and gas, or even a geothermal well, presents a significant challenge that necessitates the use of specialized tools and techniques. Circulating subs, more specifically such as the PBL, a Multiple Activation Bypass System, are engineered to effectively address and potentially eliminate these mud losses by facilitating the bypass of loss circulation material (LCM) through such tools. Pumping LCM through a directional bottom hole assembly becomes impractical for concentrations exceeding 80–100 kg/m3, and the use of cement slurries is often not permissible with most circulating subs. However, this Multiple Activation Bypass System uniquely enables multiple injections of aggressive LCM pills without any limitation on the amount that can be pumped through the system. It also accommodates cement slurries during the same run, offering a consistent and viable solution to this issue of severe mud losses. The system is straightforward, with an activation/deactivation method that is both reliable and easily detectable at the surface. The PBL, a Multiple Activation Bypass System offers a system with a proven worldwide operational efficiency rating of over 99%. Therefore, the PBL simple, proven methods that effectively reduce complexity while offering high operational and economic efficiency.