Patent attributes
A cutting apparatus and method to facilitate milling of a casing window by improving the interaction between the mill and the casing. The cutting apparatus comprises a whipstock having a plurality of ramp sections which provide a ramp profile arranged and designed to cooperate with the cutting structure of a mill to achieve a desired loading on the mill cutting elements during milling of the casing window. The plurality of ramp sections, having specific lengths and oriented at specific angles, adjust the loading on the mill as the mill cuts through the casing during formation of the casing window. The improved whipstock maintains a more balanced loading across the cutting elements during milling operations. Additional mill cutting structures may also be selected and evaluated to further balance the cutting load during window milling.
