US 7,201,238 B2 · Low friction face sealed reaction turbine rotors

Abstract

Rotary jetting tool including a rotor with axially-opposed pressure-balanced mechanical face seals. Vented upper mechanical face seal enables the rotor to be operated with the relativity low starting torque achievable using reaction forces from offset jets energized with a pressurized fluid. When rotor is displaced axially due to set-down conditions, a pressure chamber exerts a pressure imbalance on the rotor, forcing the rotor to return to a normal operating position. Alternate structure to achieve low starting torque includes a volume disposed adjacent to a lower mechanical face seal, the volume being coupled in fluid communication with the pressurized fluid. Mechanical face seal surfaces are fabricated from ultra-hard materials, such as tungsten carbide, silicon carbide, and diamond. A gage ring designed to ensure the jets remove all of the material from the gage of the protective housing before the tool can advance can be incorporated.

Claims69

Dependent claims

A rotary jetting apparatus comprising:

(a) a housing defining a fluid path for a pressurized fluid;
(b) a rotor, at least a portion of which is disposed coaxially within the housing, the rotor including a proximal end and a distal end, the rotor being configured to rotate relative to the housing, a distal surface of the rotor sealingly engaging the housing;
(c) at least one nozzle in fluid communication with the fluid path, the at least one nozzle being disposed proximate the distal end of the rotor and being configured to rotate in unison with the rotor, and to discharge a jet of the pressurized fluid;
(d) a seal head disposed within the housing adjacent to the proximal end of the rotor, so that the seal head does not rotate relative to the housing, the seal head including a distal face that sealingly engages the proximal end of the rotor;
(e) at least one of an upper mechanical face seal and a lower mechanical face seal;
and
(f) a volume disposed adjacent to one of the upper mechanical face seal and the lower mechanical face seal, the volume being coupled to a pressure at startup that reduces an amount of torque required to initiate rotation of the rotor, by reducing a friction acting on the rotor.

4 more elements

A rotary jetting tool comprising:

(a) a housing defining a fluid path for a pressurized fluid;
(b) a rotor, at least a portion of which is disposed within the housing, the rotor including a proximal end and a distal end, a distal surface of the rotor being configured to sealingly engage the housing to achieve a lower mechanical face seal;
(c) at least one nozzle in fluid communication with the fluid path, the at least one nozzle being disposed proximate the distal end of the rotor, the at least one nozzle being configured to rotate together with the rotor, and to discharge a jet of the pressurized fluid;
(d) a seal head disposed within the housing adjacent to the proximal end of the rotor and configured so that the seal head does not rotate relative to the housing, the seal head having a distal face configured to sealingly engage the proximal end of the rotor to achieve an upper mechanical face seal;
and
(e) a volume coupled to a pressure at startup that reduces an amount of torque required to initiate rotation of the rotor, by reducing a friction acting on the rotor, the volume being disposed such that one of the following is true:
(i) the volume separates the lower mechanical face seal into an inner mechanical face seal and an outer mechanical face seal, the volume being coupled in fluid communication with the fluid path;
and
(ii) the volume separates the upper mechanical face seal into an inner mechanical face seal and an outer mechanical face seal, the volume being coupled in fluid communication with an ambient region that is external to the housing.

6 more elements

A rotary jetting apparatus comprising:

(a) a housing defining a fluid path for a pressurized fluid;
(b) a pressure balancing head disposed within the housing so that the pressure balance head is enabled to move axially relative to the housing, but does not rotate relative to the housing, the pressure balancing head including:
(i) a first axial volume in fluid communication with the fluid path;
and
(ii) a distal face configured to function as an upper mechanical face seal;
(c) a rotor shaft, at least a portion of the rotor shaft being disposed within the housing, between a lower mechanical face seal and the upper mechanical face seal, so that the rotor shaft is able to move axially relative to the housing and can rotate relative to the housing, an axial movement of the rotor shaft opening a first gap in the lower mechanical face seal, the rotor shaft including:
(i) a second axial volume in fluid communication with the first axial volume;
(ii) a proximal face configured to rotatingly and sealingly engage the distal face of the pressure balancing head, to effect the upper mechanical face seal;
(iii) a lower annular face disposed distal to the proximal face, the lower annular face being configured to configured to rotatingly and sealingly engage the housing to achieve the lower mechanical face seal;
and
(iv) an orifice coupling the second axial volume in fluid communication with a pressure chamber defined by the housing, the rotor shaft, the upper mechanical face seal, the lower mechanical face seal, and the pressure chamber being configured so that pressurized fluid in the pressure chamber is enabled to escape through the first gap that is opened in the lower mechanical face seal in response to axial movement of the rotor shaft, the orifice having a size and shape selected to ensure a pressure imbalance occurring between the second axial volume and the pressure chamber forces the rotor shaft to move axially to automatically close and seal the first gap after the first gap has been opened;
and
(d) a nozzle head including at least one nozzle in fluid communication with the second axial volume, the at least one nozzle being configured to discharge a jet of pressurized fluid, the nozzle head being fixedly coupled to the rotor shaft, so that a rotation of the rotor shaft imparts a rotation to the nozzle head, and so that a rotation of the nozzle head imparts a rotation to the rotor shaft, the nozzle head being disposed external to the housing, so that a second gap separates the nozzle head from the housing, the second gap defining an extent of axial movement allowed the rotor shaft relative to the housing.

10 more elements

A method for reducing a start-up torque required to initiate a rotation of a rotary jetting tool, the method comprising the steps of:

(a) effecting a mechanical face seal between a rotatable portion of the rotary jetting tool and a non-rotating portion of the rotary jetting tool;
and
(b) one of the steps of:
(i) coupling a volume adjacent to the mechanical face seal to a source of ambient pressure that reduces a frictional drag between the rotatable portion and the non-rotating portion of the rotating jetting tool at startup of the rotary jetting tool, thus reducing a start-up torque when initiating a rotation of the rotary jetting tool;
and
(ii) coupling a volume adjacent to the mechanical face seal to a source of pressurized fluid that reduces a frictional drag between the rotatable portion and the non-rotating portion of the rotating jetting tool at startup of the rotary jetting tool, thus reducing a start-up torque when initiating a rotation of the rotary jetting tool.

3 more elements

A method for drilling a circular hole in a material, comprising the steps of:

(a) placing a rotary jetting tool adjacent to a material into which a hole is to be drilled, the rotary jetting tool including at least one nozzle configured to rotate and to emit a jet of a pressurized fluid for drilling the material;
(b) supplying the pressurized fluid to the rotary jetting tool, such that the at least one nozzle emits the jet of pressurized fluid;
(c) advancing the rotary jetting tool toward the material until a gage ring on the rotary jetting tool contacts the material into which the hole is to be drilled, preventing the at least one nozzle from directly contacting the material;
(d) applying a constant force to the rotary jetting tool so that the gage ring remains in contact with the material into which the hole is to be drilled, removal of portions of the material disposed immediately adjacent to the gage ring enabling the rotary jetting tool to advance into the material to drill the hole;
and
(e) pressure balancing an upper mechanical face seal and a lower mechanical face seal in the rotary jetting tool, the upper mechanical face seal and the lower mechanical face seal being axially opposed.

3 more elements

A method for removing foreign material from a tube, comprising the steps of:

(a) introducing a rotary jetting tool into the tube, the rotary jetting tool including at least one nozzle configured to rotate within the tube and to emit a jet of pressurized fluid;
(b) supplying a pressurized fluid to the rotary jetting tool, such that the at least one nozzle emits a jet of pressurized fluid;
(c) advancing the rotary jetting tool until a gage ring on the rotary jetting tool contacts the foreign material to be removed, the gage ring being configured to prevent the at least one nozzle from directly contacting the foreign material to be removed;
(d) applying a constant force to advance the rotary jetting tool through the tube, so that the gage ring remains in contact with the foreign material to be removed, removal of portions of such foreign material enabling the rotary jetting tool to advance farther into the tube;
and
(e) balancing a pressure between an upper mechanical face seal and a lower mechanical face seal in the rotary jetting tool, wherein the upper mechanical face seal and the lower mechanical face seal are axially opposed.

3 more elements

Dependencies are inferred from the claim text.

Low friction face sealed reaction turbine rotors

Life of this patent

Low friction face sealed reaction turbine rotors

Life of this patent

Abstract

Claims69