During drilling process, the directional drilling series provides perfect drilling performance and durability. Through continuous improvement on design of cutting tooth, blade shape and tooth arrangement, it is successful to decrease the risk of torque torsion and stick-slip so as to largely lower the bit vibration.
6" MD516QG/M223
◆Body Material: Tungsten carbide is applied to carcass with the features of flushing resistance and wear resistance.
◆Blade Quantity and Mode: 5 blade screw design which is composed of 2 long blades and 3 assistant blades to properly control torque during drilling.
◆Crown Shape: Design of shallow cone parabola shape, good for the operation of build-up and drop-off.
◆Water Nozzle Design: 6 pieces of fixed nozzles are applied to satisfy the requirements of down hole assembly and to ensure the washing and cooling of drill bit as well as the transportation of rock debris.
◆Cutting Tooth: Total 37 pieces including 21 pieces of 16 mm main cutting teeth on surface, 12 pieces of 13 mm side assistant teeth. Cutting teeth with high wear resistance and strong shock resistance are applied.
◆Gauge Protection: Containing the active gauge protection cutting tooth and ball surface tooth, the drill bit has 2” long gauge protection which helps operation on build-up and drop-off.
◆Connection Method: 3-1/2”REG. pin screw connection.
The directional drill bits were applied in horizontal well section of north Shaanxi Zizhou block with the Shanxi formation. The lithology is quartz sandstone containing 80%-90% of quartz. Totally 5 drill bits were used with the single drill bit footage of 198m-254m and average penetration rate of 2.52-3.0m/h.