纳米改性材料在水基钻井液中的减阻性能OA北大核心

The flow of water based drilling fluids in slim holes fluctuate significantly and the interface resistance between the drilling fluids and the wellbore/drilling tools is high,resulting in high flow energy loss and high equivalent circulation density(ECD)which in turn cause mud losses and stuck pipe to happen.A drag reducer DRA-1 for water based drilling fluids was synthesized with nano silica as the raw material through graft-modification,and its performance was studied.In laboratory experiment,it was found that a base mud treated with 3%DRA-1 has its flow index increased by 366.7%to 0.5064,the consistency coefficient reduced by 90.6%to 0.4847 Pa·sn,and the extreme pressure coefficient of friction reduced by 81.82%.After hot rolling at 120℃for 16 hours,the extreme pressure coefficient of friction was further reduced,indicating that DRA-1 is resistant to high temperature.When the DRA-1 treated base mud was flowing under the same conditions on a self-made steel plate and a polytetrafluoroethylene plate respectively,DRA-1 performed much better than the same type of field additives in improving the flow behavior of the mud.Operation data obtained from the well A showed that by adding 1%DRA-1 in the water based drilling fluid,the pressure loss along the circulation system was reduced by 1.937 MPa,a reduction rate of 21.61%,and lower ECD was obtained in the whole drilling operation,indicating that DRA-1 helped increase the drilling efficiency and safety,and this is very important to the increase of economic benefits and the avoidance or drilling accidents.