Plug Flow Displacement-- Model For The Well Cementation Technology Development O

In Oct. 2015, The Well Tail Pipe Cementation Of Well KS603 And Well KS10 -- The Key Appraisal Well And Exploratory Well In Shanqian Block Of CNPC Was Completed Successfully. These Two Wells Use The OMAX System Of Cement Slurry With High Temperature Resistance, Gas-Channeling Prevention Effect And High Density, And The Construction Methods Of Plug Flow Displacement And Well Cementation. Finally The Well Cementation Quality Is Proved To Be Good By The Electric Test Of The Acoustic Amplitude. They Are Praised And Approved By Party A And Well Cementation Company.

Well KS603 Is An Appraisal Well In Tarim Basin And Drilled To 5891m Using Drill Ф215.9mm. Casing Pipe Ф177.8mm+Ф182mm Is Run For The Suspension Well Cementation Of The Tail Pipe. The Density Of Cement Slurry Is 2.30SG And 2.20SG. Well KS10 Is An Exploratory Well In Tarim Basin And Drilled To 6173m Using Drill Ф215.9mm. Casing Pipe Ф177.8mm+Ф182mm Is Run For The Suspension Well Cementation Of The Tail Pipe. The Density Of Cement Slurry Is 2.50SG And 2.35SG. The Common Difficulties For The Two Wells: Deep Well, Small Annulus Gap, Long Open Hole Section, Narrow Formation Pressure Window, High Circulating Friction, High Operation Pumping Pressure, Easy Leakage During Well Cementation, Easily Polluted Cement Slurry By The Salt-Gypsum Stratum In Open Hole Section, High Performance Requirements Of The System Of Cement Slurry With High Density, Etc. According To The Above Difficulties, The System Of Cement Slurry With High Temperature Resistance, Gas-Channeling Prevention Effect And High Density Is Used In The Design Which Is Stimulated By The Corresponding Mathematical Model. Plug Flow Displacement Is Determined To Be Applied In The Construction. The Rheological Properties Of Spacer Fluid And Cement Slurry Are Well Designed To Meet The Construction Requirements Of Plug Flow Displacement. Well KS603 And Well KS10 Were Successfully Completed On Oct. 21, 2015 And Oct. 24, 2015 Respectively, And The Well Cementation Quality Is Good According To The Electric Test Results.

In Recent Years, The Well Cementation Of The Leakage Well In Shanqian Block Mostly Is Replaced By Turbulent Flow. Though The False Filter Cake On The Well Wall Is Effectively Washed And The Replacement Efficiency Is Improved, The Risk Of Leakage Is Increased, And The Leakage Of Different Levels Appears In Many Well Constructions, Thus Causing Insufficient Return Height And Influencing The Well Cementation Quality. Plug Flow Displacement Is Proved To Be Feasible In The Construction Of Leakage Well Based On The Analysis Of Theories And Data Simulation, Which Is Verified By The Two Wells. The Well Logging Results Show That The Construction Method Of Plug Flow Displacement Has Obvious Effect On Shanqian Leakage Well, With Certain Superiority. Meanwhile, The Experience Of Well Cementation Technology Of Leakage Well Is Gathered As A Good Reference For The Well Cementation Of This Type In Future.