Circulation sub and method for using same

摘要

Techniques for continuously circulating fluid into a drill string are disclosed. These techniques involve a circulation sub (108) including a tubular and a diverter valve (200A). The tubular has a first end connectable to the drill string, a second end connectable to a pipe segment, and a port (220) therein. The tubular has a fluid path (202) for allowing the fluid to flow from the pipe segment to the drill string and a circulation path (204) for allowing the fluid to flow from the port to the drill string. The diverter valve has a channel therethrough in selective fluid communication with the fluid path. The diverter valve is positionable between a flow through position for selectively allowing the fluid to flow through the fluid path and a diversion position for selectively allowing the fluid to flow through the circulation path whereby the fluid may continuously flow through the drill string.

主权项

1. A circulation sub for continuously circulating a fluid into a drill string, the drill string positionable in a wellbore penetrating a subterranean formation, the circulation sub comprising:
a tubular having a first end connectable to the drill string and a second end connectable to a pipe segment, the tubular having a port therein, the tubular having a fluid path for allowing the fluid to flow from the pipe segment to the drill string and a circulation path for allowing the fluid to flow from the port to the drill string; and a diverter valve having a channel therethrough in selective fluid communication with the fluid path, the diverter valve positionable between a flow through position for selectively allowing the fluid to flow through the fluid path and a diversion position for selectively allowing the fluid to flow through the circulation path, the diverter valve comprising:
a sleeve rotatable about an axis of the tubular to selectively block the port and a ball seatable in a neck of the tubular to selectively block the fluid path whereby the fluid may continuously flow through the drill string, the ball unseating from the neck to open the fluid path.