Rotary jet bit for jet drilling and cleaning

Abstract

A jet bit ensures precise drilling of holes through the earth's surface, such as drainholes around a well. The jet bit has front rotating orifices and jets to drill a hole in a medium larger than the diameter of the bit. The orifices directed to the rear provide thrust to propel the bit forward by enlarging the drainhole. A stationary shroud extends beyond the front orifices to maintain the front jets rotation. The jet bit may include turbine to control rotation rate and torque on front jets containing rotating shafts. A jet bit can be small enough to turn in a radius of four (4) inches from a vertical wellbore to create a horizontal drainhole. Various mechanical cutters can be mounted on the front of the jet bit to enable cutting with both jets and mechanical cutters.

We claim: 
     
         1 . A jet bit for jet drilling, comprising:
 a non-rotating outer body consisting of inlet housing and a bearing housing connected to a high pressure fluid source;   a rotating inner shaft in the outer body that is connected to and rotates a drill head;   a drill head has orifices that under high pressure fluid are angled to produce torque to turn the drill head and to produce high pressure fluid jets to drill solid materials;   a turbine consisting of one or more stationary stator blades attached to the outer body and one or more rotating rotor blades attached to the rotating shaft to rotate the shaft and the high pressure drill head;   a dynamic seal on the rotating shaft to prevent leakage of high pressure fluid past the rotating shaft to the exterior of the jet bit and reducing flow through the drill head;   a bearing assembly in the bearing housing to transfer hydraulic and mechanical axial loads on the rotating shaft to the non-rotating stationary outer body. The jet bit of  claim 1  where the fluid pressure drop across the orifices is between 500 and 40,000 pounds per square inch.   
     
     
         1 . The jet bit of  claim 1  including a turbine consisting of one or more stationary stator blades attached to the outer body and one or more rotating rotor blades attached to the rotating shaft to rotate the shaft and the high pressure drill head. 
     
     
         2 . The jet bit of  claim 1  where the inlet housing and bearing housing are combined into one housing. 
     
     
         3 . The jet bit of  claim 1  where rear directed orifices in the non-rotating outer body produce jets that produce a forward force on the drill head as it drills. 
     
     
         4 . The jet bit of  claim 4  where rear directed jets cut slots in the in the rock surrounding the jet drilled holes to increase flow of oil and gas from oil and gas bearing formations. 
     
     
         5 . The jet bit of  claim 1  where one or more side directed jets in the drill head are used to increase the diameter of the jet drilled hole. 
     
     
         6 . The jet bit of  claim 1  where angled jet bits are used in the drill head to provide torque to rotate the shaft and drill head instead of turbine blades. 
     
     
         7 . The jet bit of  claim 1  where a Moineau motor is used to rotate the shaft and high pressure drill head. 
     
     
         8 . The jet bit of  claim 1  where the bearing assembly is a ball or roller bearing. 
     
     
         9 . The jet bit of  claim 1  where the bearing assembly is a hard-metal sliding bearing that utilizes polycrystalline diamond, ceramic or other hard-metal sliding surfaces. 
     
     
         10 . The jet bit of  claim 1  where the bearing assembly is a journal bearing. 
     
     
         11 . The jet bit of  claim 1  where the dynamic seal is a labyrinth seal. 
     
     
         12 . The jet bit of  claim 1  where the dynamic seal is an o-ring seal. 
     
     
         13 . The jet bit of  claim 1  where the dynamic seal is a metal to metal seal. 
     
     
         14 . The jet bit of  claim 1  where the dynamic seal is a deformable material seal. 
     
     
         15 . The jet bit of  claim 1  where the dynamic seal is a face seal. 
     
     
         16 . The jet bit of  claim 1  where the dynamic seal is a lip seal. 
     
     
         17 . The jet bit of  claim 1  where the dynamic seal is a packing seal. 
     
     
         18 . The jet bit of  claim 1  where the dynamic seal is a nested V or a nested conical seal. 
     
     
         19 . The jet bit of  claim 1  where the dynamic seal is a mechanical seal. 
     
     
         20 . The jet bit of  claim 1  where the dynamic seal is a balanced or unbalanced seals. 
     
     
         21 . The jet bit of  claim 1  where a screen is placed in the jet bit to prevent small particles from plugging the high pressure orifices. 
     
     
         22 . The jet bit of  claim 1  where hard-metal mechanical cutters such a polycrystalline diamond (PDC), tungsten carbide, silicon carbide and silicon nitride cutters are applied to the drill head to assist the high pressure jets in drilling hard materials. 
     
     
         23 . The jet bit of  claim 1  where the drill head is contained in a shroud to protect it from mechanical damage or plugging by debris from the material being drilled. 
     
     
         24 . The jet bit of  claim 1  where the assembly is pushed forward mechanically by a tube or other means instead of by rear jets. 
     
     
         25 . The jet bit of  claim 1  where a diverter is used in an existing well to turn the jet rotating head so that it will drill inclined or horizontal lateral wells from existing wellbores. 
     
     
         26 . The jet bit of  claim 1  where a flexible tube or hose is used behind the rotating drill head to allow passage through the curved passageway in the diverter. 
     
     
         27 . The jet bit of  claim 1  where the outer body of the jet drilling assembly is flexible so that that the assembly can pass around shorter radii turns in diverters. 
     
     
         28 . The jet bit of  claim 1  where a hydraulic or electric motor is used in an existing well to rotate a flexible shaft that passes through a diverter and rotate the jet drilling assembly to drill inclined or horizontal lateral wells from existing wellbores. 
     
     
         29 . The jet bit of  claim 1  where the jet bit is used to remove cement, scale, paraffin and other materials from inside oilfield drillpipe, oil and gas production tubing, oilfield casing and from tubulars in geothermal, water, and disposal wells. 
     
     
         30 . The jet bit of  claim 1  where the jet bit is used clean the inside of industrial tubing such as heat exchanger tubes. 
     
     
         31 . The jet bit of  claim 1  where the jet bit is used to clean products in non-drilling applications. 
     
     
         32 . The jet bit of  claim 4  where the jet bit rear jets and front jets are both used for cleaning. 
     
     
         33 . The jet bit of  1  where it uses a water soluble protector cap to allow clearance through sharp transitions and protects from debris.