US 12,140,026 B2
Method of drilling an investigation well by use of auxiliary table of a dual-activity rig simultaneously with another activity on main table
Bruno Fidalgo Telles Rodrigues, Rio de Janeiro (BR); Flavia De Oliveira Lima Falcao, Rio de Janeiro (BR); Flank Melo De Lima, Macaé (BR); Joao Paulo Teixeira Da Fonseca, Rio de Janeiro (BR); Guilherme De Almeida Fernandes, Rio de Janeiro (BR); Emanuel Apoema Sortica, Rio de Janeiro (BR); and Manuel Parcero Oliveira, Rio de Janeiro (BR)
Assigned to PETRÓLEO BRASILEIRO S.A.—PETROBRAS, Rio de Janeiro (BR)
Filed by PETRÓLEO BRASILEIRO S.A.—PETROBRAS, Rio de Janeiro (BR)
Filed on Nov. 16, 2023, as Appl. No. 18/511,244.
Prior Publication US 2024/0167340 A1, May 23, 2024
Int. Cl. E21B 7/12 (2006.01); E21B 21/00 (2006.01); E21B 33/14 (2006.01); E21B 41/00 (2006.01); E21B 44/00 (2006.01); E21B 47/06 (2012.01)
CPC E21B 7/12 (2013.01) [E21B 21/001 (2013.01); E21B 33/14 (2013.01); E21B 41/0007 (2013.01); E21B 44/00 (2013.01); E21B 47/06 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A method of drilling an investigation well by use of an auxiliary table and a main table of a dual-activity rig, the method comprising:
assembling and lowering a drilling bottom-hole assembly (BHA);
starting drilling of the investigation well with control of parameters to avoid enlargement in a seabed;
maintaining remote operated vehicle (ROV) at a bottom of the investigation well;
optimizing drilling parameters of the investigation well;
drilling the investigation well at a pre-defined drilling rate between 15 and 45 m/h, thereby to guarantee data acquisition through a plurality of profiles;
reducing the flow rate in friable formations to minimize well enlargement, thereby to carry out pre-tests;
moving viscous plugs to clean the investigation well;
performing pressure measurements in permo-porous formations with a pre-test tool and with a drill bit supported at the bottom of the investigation well;
circulating seawater to clean the investigation well; and
filling the investigation well with heavy water-based drilling fluid to stabilize well walls, the drilling fluid having equivalent weight between 10.5 and 12.5 lb/gal (1.258 and 1.498 g/cm3).