Patent ID: 6688385
Filing Date: 2004-02-10
Classification: E21B

Abstract:
In combination with a cycle lifting oil/gas well having a tubing inserted into an underground reservoir to lift a fluid/gas mixture, said tubing capped with a wellhead assembly having a primary wellhead pipe (WHP), said WHP having an arrival sensor which triggers a controller programmed to open and close the well on time or pressure cycles, an improvement comprising:a trip ball cyclable up and down the tubing; said trip ball having an outside diameter slightly smaller than an inside diameter of the tubing; wherein a pressure from the reservoir pushes the trip ball up the tubing during a harvest cycle; said trip ball switches the arrival sensor, thereby ending the harvest cycle; a stop in the WHP to limit a travel of the trip ball; wherein the trip ball is a metal sphere heavier than the fluid/gas mixture; wherein the tubing further comprises a seating nipple having an inside diameter smaller than the outside diameter of the trip ball; wherein the seating nipple inside diameter further comprises a diameter suited to stop the trip ball with more than half the trip ball projecting upward from the seating nipple; wherein the seating nipple further comprises a location at a lowermost end of the tubing; a trip ball fishing tool insertable into the tubing; and wherein the trip ball fishing tool further comprises a ball valve assembly which opens during a descent and closes during a retrieve operation.