Earth boring apparatus and method offering improved gage trimmer protection

A method of drilling a borehole in a subterranean formation, comprising:

• disposing a drilling apparatus carrying a plurality of cutting structures within a borehole;
• wherein the drilling apparatus includes at least one gage trimmer sized and positioned for cutting an outer diameter of the borehole;
• wherein the drilling apparatus includes at least one protective structure sized, positioned, and configured to inhibit damaging contact with the at least one gage trimmer and has a wear resistance which is less than a wear resistance of the at least one gage trimmer;
• and
• rotating the drilling apparatus to drill out the subterranean formation to at least a drill diameter.

A method of operating a drilling system within a borehole comprising:

• disposing a drilling apparatus carrying a plurality of cutting structures within a casing;
• wherein the drilling apparatus includes at least one gage trimmer sized and positioned for cutting an outer diameter of the borehole;
• wherein the drilling apparatus includes at least one protective structure sized, positioned, and configured to inhibit damaging contact with the at least one gage trimmer and has a wear resistance which is less than a wear resistance of the at least one gage trimmer;
• disposing a drilling fluid within the casing;
• rotating the drilling apparatus within the casing;
• and
• changing the drilling fluid within the drilling system.

A method of designing a rotary apparatus for drilling a borehole in a subterranean formation, the rotary apparatus under design including a plurality of cutting structures, the method comprising:

• selecting at least one gage trimmer configured for cutting an outer diameter of the borehole;
• selecting at least one protective structure configured for inhibiting damage to the at least one gage trimmer;
• wherein the at least one protective structure has a wear resistance which is less than a wear resistance of the at least one gage trimmer;
• and
• positioning the at least one gage trimmer proximate to rotationally leading and trailing edges of the at least one gage trimmer.