How To Solve The Deformation Problem of Spiral Submerged Arc Welded Steel Pipes

(1) Pseudo-strain energy mutations mainly occur when the drill bit enters the soft soil layer and when the roller cone bit passes through the abrupt formation interface. The higher the forming hardness, the greater the pseudo strain energy when the spiral seam submerged arc welded steel pipe enters forming.

(2) When drilling into a sudden formation, 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 certain formation inclination angle conditions, the greater the drilling speed of the drill bit, the greater the longitudinal deviation of the drilling trajectory; the greater the drill bit speed, the smaller the longitudinal deviation of the drilling trajectory. When the drill bit rotation speed is lower than 2.2rad/s, the impact of the rotation speed on the longitudinal deviation of the drilling trajectory is reduced.

(4) Under a certain drill bit speed, when the local formation inclination angle is 0° and 90°, there is no impact on the drilling trajectory; when the local inclination angle gradually increases, the longitudinal deviation of the drilling trajectory increases; when the local inclination angle exceeds 45°, the impact on the drilling longitudinal deviation is reduced. The research results of this chapter are of great significance for improving the prediction accuracy of the drilling trajectory of tri-cone drill bits in steep formations and lay a theoretical foundation for correcting the drilling trajectory of spiral seam submerged arc welded steel pipes through horizontal pilot holes.