Method and apparatus for jet-assisted drilling or cutting
An abrasive cutting or drilling system, apparatus and method, which includes an upstream supercritical fluid and/or liquid carrier fluid, abrasive particles, a nozzle and a gaseous or low-density supercritical fluid exhaust abrasive stream. The nozzle includes a throat section and, optionally, a converging inlet section, a divergent discharge section, and a feed section.
1. An apparatus for cutting or drilling by means of a gas-carrying or low-density fluid-carrying abrasive jet stream containing abrasive particles, said apparatus comprising:
an abrasive-laden primarily liquid or high density supercritical fluid under predetermined pressure and temperature;
a nozzle having an inlet converging conic section for admitting said abrasive-laden primarily liquid or high density supercritical fluid under predetermined pressure and temperature and for increasing the velocity of said abrasives and fluids;
said nozzle having a narrow diameter aperture throat section to accelerate the velocity of said abrasive particles;
said nozzle having a diverging conic discharging section, whereby said primarily liquid or high density supercritical fluid expands into its gas carrying or low-density phase; and
wherein said inlet converging conic section leads to said narrow diameter aperture throat section, which further leads to said diverging conic discharging section.
2. The apparatus of claim 1 including a feeding section in advance of the inlet converging section of the nozzle having a plurality of blades or vanes at pre-arranged angles to induce a spinning motion to the primarily liquid or high density supercritical fluid and abrasives.
3. The apparatus of claim 1 further comprising a feeding section with a plurality of diverting blades or vanes in a predetermined orientation, wherein one end of said feeding section is in contact with said inlet section of said nozzle.
4. The apparatus of claim 1 wherein said primarily liquid or high density supercritical fluid is chosen from the group consisting of carbon dioxide, water, nitrogen, propane, butane, freon, and methane.
5. The apparatus of claim 1 including a plurality of said nozzles arrayed on a single head.
6. An apparatus for cutting or drilling by means of a gas-carrying or low density fluid-carrying abrasive jet stream containing abrasive particles, said apparatus comprising:
an abrasive-laden primarily liquid or high density super critical fluid under predetermined pressure and temperature;
an inlet converging conic section for admitting said abrasive-laden primarily liquid or high density supercritical fluid under predetermined pressure and temperature and for increasing the velocity of said abrasives and fluids;
a narrow diameter aperture in fluid communication with said inlet converging conic section to accelerate the velocity of said abrasive particles;
a diverging conic discharging section in fluid communication with said narrow diameter aperture, whereby said primarily liquid or high density supercritical fluid begins to expand into its gas carrying or low-density phase.
7. An apparatus of claim 6 including a feeding section in advance of the inlet converging section of the nozzle, said feeding section having a plurality of blades or vanes at pre-arranged angles to induce a spinning motion to the primarily liquid or high density supercritical fluid and abrasives.
8. A method for drilling and cutting comprising the steps of:
providing an abrasive-laden primarily liquid or high density supercritical fluid under predetermined pressure and temperature, wherein said abrasive-laden primarily liquid or high density supercritical fluid comprises a suspension of said abrasive particles in said abrasive-laden primarily liquid or high density supercritical fluid;
imparting a spinning motion to the combination of primarily liquid or high density supercritical fluid and abrasives in advance of the inlet converging section;
delivering said abrasive-laden primarily liquid or high density supercritical fluid to a nozzle;
increasing velocity of said abrasive-laden primarily liquid or high density supercritical fluid as it passes through a flow-restriction in said nozzle;
beginning expansion of said primarily liquid or high density supercritical fluid into its gaseous or low-density state as it passes through said nozzle;
transferring kinetic energy from said expanding fluid to said abrasive particles to accelerate velocity of said particles; and
discharging a gas-carrying or low-density supercritical fluid-carrying abrasive jet stream containing abrasive particles from said nozzle.
9. The method of claim 8 wherein said primarily liquid or high density supercritical fluid is chosen from the group consisting of carbon dioxide, water, nitrogen, propane, butane, freon, and methane.
10. The method of claim 8 including the additional step of introducing an additive to the liquid or high density supercritical fluid and abrasives prior to delivering to the nozzle.