Drill bits for drilling wells

A device including a drill bit, said drill bit comprising:

• a predetermined number N of lug members arranged at a 360/N degree angle to each other and joined by an upper support member, each said lug member includes a through vertical hole in the upper portion;
• N shafts disposed substantially horizontally, each said shaft is immovably bolted through a ‘C’-shaped bracket to the lower portion of each said lug member, said shafts are fixedly coupled to each other collectively forming a ‘N-beam star’ with a central hub, each said shaft has a number of surface axial grooves for supplying lubricant;
• one inner and one outer roll bearings rotatably mounted on each said shaft inwardly and outwardly with respect to the corresponding lug member;
• an inner and an outer conical cutter members, each individually fixedly coupled to the corresponding inner or outer roll bearing;
• a sleeve containing lubrication liquid and having a base mounted upon the upper support member;
• a central channel disposed within said sleeve, said central channel includes a lower portion outstanding below the sleeve's base, and terminated with an opening that is controllably closed or opened with a reciprocating valve-plate;
• an annular piston capable to reciprocate in the bottom region of said sleeve, snug-fitting between the sidewalls of said sleeve and said channel, said piston is furnished with at least one discharge valve outletting the lubrication liquid through the piston at a predetermined reverse pressure;
• a spring disposed at the bottom of said sleeve below said piston;
• N rods mounted in the bottom region of said sleeve and sealably inserted through said holes of said lug members, the upper ends of said rods are coupled to said piston, and the lower ends of said rods are coupled to said valve-plate;
• and lubrication channels arranged in said lug members, communicating the bottom region of said sleeve under the piston with said inner and outer roll bearings.

A device including a drill bit, said drill bit comprising:

• a predetermined number N of lug members arranged at a 360/N degree angle to each other and joined by an upper support member, each said lug member includes a through vertical hole in the upper portion;
• N hollow shafts disposed substantially horizontally, each said shaft is immovably bolted through two ‘C’-shaped brackets to the lower portion of each said lug member, said shafts are fixedly coupled to each other collectively forming an ‘N-beam star’ with a central hub, said shafts each has an internal through shaft channel, said internal shaft channels communicate through the hub, each said shaft has a number of surface axial grooves for supplying lubricant liquid;
• one inner and one outer roll bearings rotatably mounted on each said shaft inwardly, and outwardly with respect to the corresponding lug member, and one intermediate roll bearing mounted on each shaft between said two ‘C’-shaped brackets;
• an inner, an intermediate, and an outer conical cutter members, each individually fixedly coupled to the corresponding inner, intermediate, or outer roll bearing;
• a sleeve containing lubricant liquid and having a base mounted upon the upper support member;
• a central channel disposed within said sleeve, said central channel includes a lower portion outstanding below the sleeve's base, and terminated with an opening that is controllably closed or opened with a reciprocating valve-plate;
• an annular piston capable to reciprocate in the bottom region of said sleeve, snug-fitting between the sidewalls of said sleeve and said channel, said piston is furnished with at least one discharge valve outletting the lubrication liquid through the piston at a predetermined reverse pressure;
• a spring disposed at the bottom of said sleeve below said piston;
• N cooling vessels filled with suitable coolant, mounted on each said lug member below the sleeve's bottom, said cooling vessels are communicated via said internal shaft channels and via return channels arranged between said vessels, one of the cooling vessels having a circular piston snug-fitting into and capable to reciprocate within the cooling vessel;
• N rods mounted in the bottom region of said sleeve and sealably inserted through said holes of said lug members and through said cooling vessels, the upper ends of said rods are coupled to said piston, the lower ends of said rods are coupled to said valve-plate, one of said rods is coupled to said circular piston of the corresponding cooling vessel;
• and
• lubrication channels arranged in said lug members, communicating the bottom region of said sleeve under the piston with said inner, intermediate, and outer roll bearings.