Method and apparatus for cementing while running casing in a well bore

摘要

An improved method and apparatus for dropping a ball, plug or dart during oil and gas well operations (e.g., cementing operations) employs a specially configured valving member with curved and flat portions that alternatively direct fluid flow through a bore or opening in the valving member via an inner channel or around the periphery of the valving member in an outer channel. In one embodiment, the ball(s), dart(s) or plug(s) are contained in a sliding sleeve that shifts position responsive to valve rotation. An optional indicator indicates to a user or operator that a ball or plug has passed a selected one of the valving members.

主权项

1. A ball and plug dropping head for use in sequentially dropping one or more balls and plugs into a well casing string, comprising:
a) a module having an upper end with an inlet adapted to be fluidly connected in line with the lower end of a top drive; b) the well casing string; c) the module having a lower end with an outlet that is generally aligned with the inlet and that is connected to the well casing string; d) the module having a main flow channel that connects the inlet and the outlet; e) the module having a plurality of sections spaced between the inlet and the outlet, at least some of the sections being valves with valving members, each valving member having a flow bore, and being movable between open flow and closed flow positions, the module including sections that are not valves; f) the module having one or more fluid flow channels with a curvature, wherein said one or more fluid flow channels enable fluid to bypass the valving members when one of the valving members is in the closed flow position each fluid flow channel valving member having a curved surface that has the same curvature as the curvature of the fluid flow channel; g) at least one of the valving members having a cross section that, in the closed flow position, does not valve fluid flow in the main flow channel; h) wherein fluid flow in the main channel flows around the valving member when the valving member is in the closed flow position and through the valving member when the valving member is in the open flow position; I) wherein in the open flow position each valving member bore enables a ball or plug to pass therethrough; j) wherein in the open flow position each valving member flow bore enables circulating fluid to pass downwardly through said flow bore when neither the ball nor plug is in the valving member flow bore; and k) wherein the valves and sections that are not valves are connected with threaded connections.