(1) The sudden change of pseudo-strain energy mainly occurs when the drill bit enters the soft soil layer and the cone bit crosses the interface of the sudden change formation. The higher the forming hardness, the greater the pseudo strain energy of the spiral seam submerged arc welded steel pipe when it enters the forming process.
(2) When drilling into the formation suddenly, the spiral seam submerged arc welded steel pipe moves longitudinally and the drill bit vibrates. The greater the hardness of the formation, the greater the amplitude of the drill bit.
(3) Under the condition of a certain stratum dip, the greater the drilling speed of the drill bit, the greater the longitudinal deviation of the drilling trajectory, and the greater the drill bit speed, the smaller the longitudinal deviation of the drilling trajectory. When the bit rotation speed is lower than 2.2rad/s, the influence of the rotation speed on the longitudinal deviation of the drilling trajectory is reduced.
(4) At a certain bit rotation speed, when the local formation dip angle is 0° and 90°, it has no effect on the drilling trajectory; when the local dip angle gradually increases, the longitudinal deviation of the drilling trajectory increases; when the local dip angle exceeds 45°, The influence on the trajectory of the drilling longitudinal deviation is reduced. The research results in this chapter are of great significance for improving the prediction accuracy of the tri-cone drill bit in steep formations and lay a theoretical foundation for the correction of the spiral seam submerged arc welded steel pipe drilling trajectory through the horizontal pilot hole.
Post time: Jun-24-2021