| 摘要 |
<p>A preferred novel circulating sub (300) includes an electric motor (310), hydraulic intensifier, connecting rod (360), valve sleeve (370), valve plug (375), and angled nozzles (430). Upon activation of the circulating sub (300) the electric motor (310) drives the valve sleeve (370) over the valve plug (375), causing a flow of drilling fluid to exit the angled nozzles (430). Upon deactivation of the circulating sub (300) the electric motor (310) removes the valve sleeve (370) from the valve plug (375), allowing the flow of drilling fluid to once again flow to the drill bit (125). Because the electric motor (310) is reversible, the circulating sub (300) can be repeatedly activated and deactivated.</p> |
