A new rotating mousehole tool allows makeup and breakout of drillstring sections without interruption of normal drilling to improve drilling efficiency on top-drive rigs, according to tool developer International Tool Co. Inc.
During kelly drilling, the tool can be used as a normal mousehole.
The toot is called the Phantom Mouse because it sits below the rig floor and can be covered when not in use (Fig. 1).
The tool has been field-tested for more than a year on Global Marine Drilling Co.'s top drive jack up, Adriatic IV.
The rig crew can use the rotating mousehole to makeup and set back stands of drill pipe simultaneously while the top drive drills ahead. The tool does not makeup the pipe to the full torque because it has a maximum rating of 1,500 ft lb, depending on the air pressure available. However, the tool joints are made up adequately for setting back in the derrick. The top drive is later used to tighten the stand to full torque once the pipe is placed in the drillstring.
The tool can makeup bottom hole assemblies, including drill collars, stabilizers, and other components, before they are needed. Normal button insert drill collar slips are used in the rotating mousehole tool bowls to prevent making grooves in the pipe in case of inadvertent slipping.
The rotating mousehole can also be used to breakout and lay down drill pipe during the last trip out of the hole.
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