Torque control device for downhole milling

摘要

A support mechanism for a mill, particularly usable with a whipstock and driven by a downhole motor supported by coiled tubing is disclosed. The support mechanism comprises a wearable ring adjacent the cutting structure which, when assembled into the downhole assembly, keeps the rotating blades away from the whipstock face and oriented toward the casing to be cut. As the milling progresses, the support mechanism wears away to allow advancement of the mill into the casing to complete the formation of the window or opening.