Drilling fluid technology of anti-temperature in the third interval about Yi 185 well

Amine sulphonated polymer and anti-temperature drilling fluid were researched and developed in order to ascertain the gas and oil deposits at Shasi Section in Yi 185 Block in Bonan Sag. The experiment of evaluation showed that the drilling fluid had high salt resistant performance, good inhibition capability and good rheology behavior under the temperature of 200 ℃. The drilling fluid was applied in Yi 185 well. With the help of onsite drilling fluid maintenance and handling technics, the demand of engineering drilling was met though taking these measures of rational density supporting, strengthening inhibition and formation sealing. The wellbore wall was stability and the wellbore quality was good with the 5.18% hole diameter enlargement rate. At last, the successful explorating provided valuable base data to further research and develop Yi 185 block.