Patent attributes
A method (50) and an assembly (10) for milling an obstruction disposed within a wellbore (W) includes a milling module (12) having a motor (22) rotating a milling bit (14), a first electronics cartridge (26) for controlling the motor based upon a motor torque value, a tractor module (16, 18) for engaging with the wellbore and providing a push force against the wellbore to urge the milling assembly in a direction of the milling bit, and a second electronics cartridge (28) for controlling a push force value of tractor module. The method involves rotating the milling bit (54) and engaging the tractor module with the wellbore (56), and adjusting, iteratively, the operation (58) based on a calculated torque value and a calculated push force value to maintain the calculated values at around a target torque value and below a push force limit value (66, 70).
