Major Achievements in The Application Of One-trip Drilling Technology For Oil And Gas Wells in Sichuan And Chongqing Areas

Well Miantan 1 is a key exploration well deployed in the Zitong low uplift zone of the top hidden structure of the Changxing Formation in northwest Sichuan, with a designed well depth of 6,885 meters. The well was drilled on March 19, and on March 31, it broke the record of 333.4 mm large borehole footage in the Sichuan and Chongqing area with 1,100 meters.
In order to ensure that a single drill bit drills more footage, Chuandong Drilling Company optimized the three-way construction plan and customized a high-performance five-blade PDC according to the geological characteristics of the three-way formation in the block, such as easy collapse, mud bagging, and strong pulping ability. The drill bit is equipped with a pulse nozzle to enhance the aggressiveness; during the drilling process, on the premise of meeting large displacement drilling, the drill bit speed is reduced to slow down the early wear of the drill bit.

The team gave full play to the advantages of the digital well team and used the integrated platform to conduct sensitivity analysis of drilling parameters, mechanical penetration rate and well inclination control, closely tracked the drilling situation 24 hours a day, and adjusted the drilling pressure, rotation speed, displacement and torque in real time. At the same time, we strive to seize the timeliness of the work, and technical cadres follow the work throughout the entire process to strengthen the team's ability to work, and the timeliness of column connection, inspection and maintenance is significantly improved.

This time, the record for single-trip drilling footage of a 333.4 mm wellbore in the Sichuan-Chongqing area was refreshed. The average mechanical drilling speed reached 20.17 meters/hour, which was 59% higher than that of adjacent wells. At present, the optimal index for the three 333.4 mm wellbore in the Zitong block in northwest Sichuan is to be drilled in three passes. Well Miantan 1 is expected to break this index and achieve the completion of drilling in two passes.

This new record of drilling footage per trip has provided valuable experience for improving the speed and efficiency of subsequent new well openings in the area, and the conventional oil and gas speed-increasing project has once again received strong support.