US 12,276,192 B2
System and method for construction and completion of production and injection wells in the pre-salt fields
Cristiano Eduardo Agostini, Santos (BR); Marcos Jun Tsuchie, Santos (BR); Marcos Vinicius Barreto Malfitani, Santos (BR); Reinaldo Akio Tomita, Santos (BR); and Roger Savoldi Roman, Santos (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 Dec. 20, 2023, as Appl. No. 18/391,032.
Claims priority of application No. 1020220266883 (BR), filed on Dec. 27, 2022.
Prior Publication US 2024/0209691 A1, Jun. 27, 2024
Int. Cl. E21B 7/18 (2006.01); E21B 10/26 (2006.01); E21B 49/00 (2006.01)
CPC E21B 7/185 (2013.01) [E21B 10/26 (2013.01); E21B 49/00 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A method for construction and completion of production and injection wells in pre-salt fields, wherein the method comprises three drilling phases with the running in of two casings, the method comprising:
a first drilling phase comprising drilling with a drill bit or a drill bit and a reamer, and subsequently running in a conductive casing with a diameter of 30″ (76.2 cm) or 36″ (91.44 cm);
a second drilling phase comprising drilling with a drill bit and water based fluids until close to the base of a saline formation, maintaining a minimum distance above a reservoir; wherein the second drilling phase includes drilling with a first drilling fluid and a second drilling fluid that is different than the first drilling fluid, wherein the first drilling fluid is seawater;
a third drilling phase comprising drilling to a final programmed depth of a well, drilling the remainder of the saline formation; and
completing the well.