Abstract: A milling apparatus for cutting a tubular in a wellbore includes a cutting element on a tool body configured to cut the tubular in a wellbore when the cutting element is activated when the tool is moving upward inside the tubular. The cutting element cuts the tubular to form cuttings that fall into an annulus between the tubular and the wellbore. An agitator below the cutting element agitates the cuttings in the annulus to aid the cuttings to move from the annulus into the wellbore below the milling apparatus.

Abstract: Dual section mills are selectively sequentially operated by locking an actuator for the backup mill as the primary mill has blades extended with internal flow through a housing. When the primary mill is spent the support string is shifted to defeat a lock on an actuation piston for the backup mill so that its blades can extend and continue to mill to finish the job. The blades of the primary mill continue to rotate in the already milled portion of the window as the secondary mill enlarges the window. Another way the secondary mill is actuated is to open access to flow to the secondary mill by removing a pressure barrier such as a valve or a disappearing plug, for example.

Abstract: A milling apparatus for cutting a tubular in a wellbore includes a cutting element on a tool body configured to cut the tubular in a wellbore when the cutting element is activated when the tool is moving upward inside the tubular. The cutting element cuts the tubular to form cuttings that fall into an annulus between the tubular and the wellbore. An agitator below the cutting element agitates the cuttings in the annulus to aid the cuttings to move from the annulus into the wellbore below the milling apparatus.

Abstract: Dual section mills are selectively sequentially operated by locking an actuator for the backup mill as the primary mill has blades extended with internal flow through a housing. When the primary mill is spent the support string is shifted to defeat a lock on an actuation piston for the backup mill so that its blades can extend and continue to mill to finish the job. The blades of the primary mill continue to rotate in the already milled portion of the window as the secondary mill enlarges the window. Another way the secondary mill is actuated is to open access to flow to the secondary mill by removing a pressure barrier such as a valve or a disappearing plug, for example.