Method for regaining mud circulation in operating well and device for its embodiment

Abstract

Run into a well, e.g., in a tube, on a pipe string is a hydromechanical cleaner. The bridge is washed out by the direct desending flow of drilling mud pumped through the pipe string 2. The cleaner is moved downward as the bridge is washed out by moving the pipe string. Ascending flow of drilling mud rotates cleaning heads in opposite directions. Cutting knives of the cleaning heads mechanically remove deposits from the walls of tubing 1. Deposits from the walls are removed mechanically during running of the cleaner into the well and during its lifting from the well. Products of the washed out bridge and deposits are removed from the well by an ascending flow through the side branch pipe of the wellhead circulating head. The device for embodiment of the method includes also a mechanism for moving the pipe string and a pump unit.

Dependencies are inferred from the claim text.