Behaviour of polymer muds under high pressure – high temperature conditions

摘要: A well is classified as a HPHT (High Pressure High Temperature) if the static bottomhole temperatures are greater than 350 °C and when formation pressures exceed 1800 kg/m3 ECD. Mud weights high 2400 may be required to maintain proper control. The temperature of drilling fluid circulating in range from 0 150 it important that acceptable rheological properties within whole range. mud will strongly depend on pressure variations. problems regarding wells mostly due ECD cuttings transport.In order control measure viscosity for deep we have conducted laboratory experiments deal with aging at different polymer mud, effects field mud. We also calculated annular using Landmark Wellplan software. To calibrate instruments, i.e. Physica viscometer Fann viscometer, used ubelohde, known give an exact value fluid. calibration liquid was 2-stroke motor oil amounts Exxsol-D60 added.The were mixture water HEC put three incubators 20 °C, 60 90 1, 3, 8, 11, 15 days. results showed decreased rapidly solutions aged highest most decrease took place during first day aging.In real (field) exposed used. negligible compared effects. During measurements experienced increased more significant °C.Based obtained evaluation implication pressure, able draw following main conclusions:• Laboratory very educational. learn reality not straight forward enlightening.• dependant temperature.• combined effect negligible.• differences did show any temperatures.