Apparatus for washover featuring controllable circulating valve

摘要

In a drill string connected to a wash pipe for retrieval of a fish in a well borehole, an apparatus comprising a connected tubular member therebetween having an internal movable sleeve. The sleeve is located close over a set of bypass ports to the exterior. The ports are selectively opened or closed; when closed, the fluid flow is directed to the fish in the wash pipe. A method of washing is set forth including the steps of controlling fluid flow so that, during running in of the wash pipe over the fish, fluid is bypassed. The bypassing occurs during the fish engagement improving speed of running in up to the time the wash pipe telescopes significantly over the fish.