Torsion type universal joint for horizontal well

A torsion type universal joint for horizontal well in workover on horizontal wells of oil fields comprises an spherical upper joint 1, an O-shaped seal ring 2, a steel ball 3, a spherical locking housing 4 and a spherical lower joint 5, wherein in the seal groove designed between the spherical upper joint 1 and the spherical lower joint 5 is positioned the O-shaped seal ring, the steel ball 3 is seated in the ball holder of the spherical lower joint 5 for mating the torsion groove of the spherical upper joint 1; then the spherical locking housing 4 is passed through the spherical lower joint 5 and connected to the screw at the lower end of the spherical upper joint 1. The utility model has overcome the difficulty the drilling tool has in settling down into well sections with large curvature that the torsional moment given by the rotary is very difficult to be transmitted to the drill head or milling tool, and can be widely used in horizontal well workover of oil fields.