Published: 02/12/2021
Published: 02/12/2021
When drilling the surface sections of wells through a vugular, naturally fractured formation, a Middle East operator frequently experienced total circulation losses. These losses resulted in stuck pipe, high costs for lost drilling fluid, challenges related to cuttings and returns handling at surface, and well control risks because of a shallow flowing aquifer.
Conventional lost circulation material (LCM) minimized losses while drilling wells at low inclinations, but the conventional materials were unable to stop or slow the losses when drilling
at high inclinations.
ThixoCRETE solution combines lightweight high-performance trimodal cement and a thixotropic additive to rapidly deliver high gel strength and compressive strength. Its optimized solids content and plugging efficiency rapidly plugs large voids and fractures so that drilling can continue.
ThixoCRETE solution was pumped by gravity feeding from approximately 200 ft above a loss zone while continuously filling the annulus with 9.5-lbm/galUS brine at approximately 1,000 galUS/min to maintain fluid level to surface.
The 10.5-lbm/galUS ThixoCRETE solution was designed to develop high gel strength as soon as pumping stopped. After the cement was placed, the operator managed to continue circulating with 90% returns of drilling fluids to surface, reducing from total losses to an acceptable 42 bbl/h.
To drill high-inclination wells through a formation that experiences total circulation losses and shallow water flow, an operator in the Middle East used ThixoCRETE lightweight lost circulation cementing solution to rapidly manage losses.
