Oil leakage preventing device used for oil production of screw pump

The invention relates to the technical field of crude oil exploitation, in particular to an oil leakage preventing device used for oil production of a screw pump. The device comprises an upper body, alower body, a guide sleeve and a sphere, wherein the upper body is provided with an inner cavity in the shape of a straight pipe; the lower body is of a three-way structure and comprises a straight through portion and a side through portion, and one end of the side through portion communicates with the straight through portion; the upper body is coaxial with the straight through portion; one endof the upper body is in sealed connection with one end of the straight through portion through a flange; the guide sleeve is embedded into the upper body; the sphere is arranged in the lower body andcan move in the straight through portion and the side through portion; an elastic component is arranged in the side through portion, one end of the elastic component abuts against the sphere, and theother end of the elastic com