APPLICATION OF CEMENT SLURRIES CONTAINING GAS BLOCKING AGENTS FOR THE CEMENTING OF CASINGS IN ENVIRONMENTS WITH ABNORMALLY HIGH FORMATION PRESSURE AND HIGH TEMPERATURES.
Beley, Ivan I. – Cand.Tech.Sci., senior scientific employee, well cementing department, LLC “TyumenNIIgiprogaz”, firstname.lastname@example.org
Kuyabin, Andrey G. – head of cementing slurries laboratory , LLC “TyumenNIIgiprogaz”, email@example.com
Marinin, Valery I. – Cand.Tech.Sci., deputy general director and chief geologist, LLC “Gazprom dobycha Urengoy”, firstname.lastname@example.org
Khubatulin, Ravil M. – engineer 1st grade, well drilling department, LLC “Gazprom dobycha Urengoy”, email@example.com
Lazarev, Vladimir B. – deputy head of operations, CCS branch, LLC “Gazprom burenie”, firstname.lastname@example.org
Ivanishin, Mikhail A. – first deputy director, chief engineer, Urengoy Burenie branch of LLC “Gazprom burenie”, email@example.com
Kazantsev, Vladimir V. – head of department, OJSC NTF “Efiry Tsellulozy”, firstname.lastname@example.org
Antonenko, Denis V. – head of well cementing department, LLC “Service Centre SMB”, email@example.com
Key words: cement slurry, permeability blocker, casing, cement job, overpressure.
The article reviews the issues of cement jobs in exploration wells drilled in HPHT gas-bearing formations. To prevent gas migration during casing string cementing, various compositions of cement slurries furnished with chemical permeability blockers. Given low fluid loss, these chemicals provide for short cement gellation period and speedy structurization in the course of cement hardening.
Field tests of cement slurries complete with chemical gas blocker were run while running cement job on 140 mm production casing in exploration well No. 614 in Yen-Yakha area (4,070 m setting depth). Combined with other engineering solutions (e.g., mixing total cement volume on the surface, additional backpressure generation for the duration of bottomhole cement portion gellation, etc.) cement systems with enhanced permeability blocking capacity proved reliable means of prevetion of WOC gas migration.