Replacement device for valve ball and valve ball seat of oil pump

The invention discloses a replacement device for a valve ball and a valve ball seat of an oil pump. The replacement device comprises a first shell and a second shell, wherein one end of the first shell is cylindrical, and the valve ball seat is concentrically arranged in the first shell; an inner thread is arranged on the lower portion of the end, where the valve ball seat is arranged, of the first shell, and the inner thread is connected with one end of the second shell; the other end of the second shell is in threaded connection with a third shell; a ball storage area is arranged on one side of the first shell; the valve ball is arranged in the ball storage area; an oil via hole is formed in the middle of the valve ball seat; a hollow pipe penetrates through the first shell, the second shell and the third shell; one end of a convex ring piston head is connected in the upper end of the hollow pipe through a snap spring; and the other end of the convex ring piston head is in threaded connection with the pisto