Drill bit systems with temperature sensors and applications using temperature sensor measurements

A formation drill bit system, comprising:

• a) a shank defining a longitudinal axis and having a proximal end and a distal end, said shank adapted to being rotated about said longitudinal axis;
• and
• b) a drill head fixed to a distal end of said shank, said head having a plurality of stationary blades separated by a plurality of flutes, each of said plurality of blades comprising a pad having a tungsten carbide matrix with a plurality of natural diamond cutting elements on a surface thereof;
• and
• c) at least one temperature sensing element, said at least one temperature sensing element including a first temperature sensor situated at a location adjacent to a pad of a first of said plurality of blades and arranged for sensing a local temperature of said first blade at said location.

A formation drilling system, comprising:

• a) a drill string having a proximal end and a distal end;
• b) a drill bit attached to said distal end of said drill string;
• and
• c) a reamer located proximal said distal end of said drill string, said reamer comprising
• i) a hollow body having a wall and adapted to being rotated about a longitudinal axis;
• ii) a plurality of blades circumferentially spaced about an outer circumference of said hollow body wall and defining a plurality of flutes, each of said plurality of blades having a leading face in a direction of rotation about said longitudinal axis, each said blade having a plurality of cutting elements arranged on a leading face of the blade;
• and
• iii) at least one temperature sensing element, said at least one temperature sensing element including a first temperature sensor situated at a location adjacent to a first cutting element of a first of said plurality of blades and arranged for sensing a local temperature of said first blade at said location.

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

• a) drilling the formation with a drill bit including (i) a shank defining a longitudinal axis and having a proximal end and a distal end, said shank adapted to being rotated about said longitudinal axis, (ii) a drill head fixed to a distal end of said shank, said head having a plurality of blades separated by a plurality of flutes, each of said plurality of blades having a distal end and either a plurality of cutting elements arranged on a leading edge of the distal end of the blade or on a pad on the blade, and (iii) a plurality of temperature sensing elements, at least a first sensor of said plurality of temperature sensing elements located at a first location adjacent either a cutting element arranged on a leading edge of the distal end of a first blade or adjacent a pad on said first blade and arranged for sensing a local temperature of said first blade at said first location, and at least a second sensor of said plurality of temperature sensing elements located at a second location either distant from said cutting elements and arranged for sensing a reference temperature or adjacent either a cutting element arranged on a leading edge of the distal end of a second blade or adjacent a pad on said second blade and arranged for sensing a local temperature of said second blade at said second location;
• b) providing a processor coupled to said plurality of temperature sensor elements;
• c) with said first sensor, sensing a local temperature of said first blade at said first location;
• d) with said second sensor, sensing either a local temperature of said second blade or a reference temperature at said second location;
• e) transmitting to said processor data relating to said local temperature of said first blade at said first location and to said either a local temperature of said second blade or a reference temperature at said second location;
• f) processing said data with said processor in order to obtain information regarding at least one of said drill bit system and said geological formation.