Description job: FRACSEAL application
Operator: Middle East
Type of fluids: OBM
Phase: 121/4” directional hole
Potential problem : Total loss circulation / Sloughing of sand
At depth of 6,100ft, the active system was pretreated with 7ppb FRACSEAL fine and also was mixed 150bbl LCM pill consisting 120ppb blended conventional LCM and FRACSEAL (20ppb FRACSEAL medium, 20ppb FRACSEAL coarse, 20ppb Steel Seal, 20ppb LC Lube-Fine, 20ppb Marble Coarse, 10ppb Walnut Coarse and 10ppb Mica Coarse) to anticipate any severe loss circulation.
At the 121/4” expected loss zones are at Wara and Safaniya formations (both are similar to Wasia formation), this section was drilled using Oil Base Mud at 75pcf containing 7ppb FRACSEAL fine as pre-treatment and maintained by adding 2 sacks per hour of FRACSEAL fine while drilling in the expected loss zones. No down hole losses were experienced while drilling through Wara (6,224 ft) & Safaniya (6,401ft) formations. Continue drilling with same oil base mud containing 7ppb FRACSEAL fine through Khafji formation (which is unconsolidated sand) before entering Shuaiba formation. Khafji formation was stabilized without any partially down hole losses and differential sticking.
While entering top of Shuaiba formation, mud system contained 7ppb of FRACSEAL fine and maintained by adding 2 sacks of FRACSEAL fine. The Shuaiba section was drilled from 8,678ft to 9,229ft without any losses. Continued drilling the 121/4” directional hole to casing point at 10,347ft with full returns. To improve borehole cleaning, tandem sweeps of 15bbls LoVis and 30bbls HiVis were pumped for every 30–45 feet of formation drilled.