Abstract:
In one aspect of the invention, a downhole tool string component comprises a fluid passageway formed between a first and second end. A valve mechanism is disposed within the fluid passageway adapted to substantially cyclically build-up and release pressure within the fluid passageway such that a pressure build-up results in radial expansion of at least a portion of the fluid passageway and wherein a pressure release results in a contraction of the portion of the fluid passageway. The valve mechanism disposed within the fluid passageway comprises a spring. Expansion and contraction of the portion of the fluid passageway varies a weight loaded to a drill bit disposed at a drilling end of the drill string.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This patent application is a continuation of U.S. patent application Ser. No. 12/039,635, which is a continuation of U.S. patent application Ser. No. 12/039,608, filed on Feb. 28, 2008, now U.S. Pat. No. 7,762,353, which is a continuation-in-part of U.S. patent application Ser. No. 12/037,682, filed on Feb. 26, 2008, now U.S. Pat. No. 7,624,824, which is a continuation-in-part of U.S. patent application Ser. No. 12/019,782, filed on Jan. 25, 2008, now U.S. Pat. No. 7,617,886, which is a continuation-in-part of U.S. patent application Ser. No. 11/837,321, filed on Aug. 10, 2007, now U.S. Pat. No. 7,559,379, which is a continuation-in-part of U.S. patent application Ser. No. 11/750,700, filed on May 18, 2007, now U.S. Pat. No. 7,549,489, which is a continuation-in part of U.S. patent application Ser. No. 11/737,034, filed on Apr. 18, 2007, now U.S. Pat. No. 7,503,405, which is a continuation-in-part of U.S. patent application Ser. No. 11/686,638, filed on Mar. 15, 1997, now U.S. Pat. No. 7,424,922, which is a continuation-in-part of U.S. patent application Ser. No. 11/680,997, filed on Mar. 1, 2007, now U.S. Pat. No. 7,419,016, which is a continuation-in-part of U.S. patent application Ser. No. 11/673,872, filed on Feb. 12, 2007, now U.S. Pat. No. 7,484,576, which is a continuation-in-part of U.S. patent application Ser. No. 11/611,310, filed on Dec. 15, 2006, now U.S. Pat. No. 7,600,586. This patent application is also a continuation-in-part of U.S. patent application Ser. No. 11/278,935, filed on Apr. 6, 2006, now U.S. Pat. No. 7,426,968, which is a continuation-in-part of U.S. patent application Ser. No. 11/277,394, filed on Mar. 24, 2006, now U.S. Pat. No. 7,398,837, which is a continuation-in-part of U.S. patent application Ser. No. 11/277,380, filed on Mar. 24, 2006, now U.S. Pat. No. 7,337,858, which is a continuation-in-part of U.S. patent application Ser. No. 11/306,976, filed on Jan. 18, 2006, now U.S. Pat. No. 7,360,610, which is a continuation-in-part of U.S. patent application Ser. No. 11/306,307, filed Dec. 22, 2005, now U.S. Pat. No. 7,225,886, which is a continuation-in-part of U.S. patent application Ser. No. 11/306,022, filed Dec. 14, 2005, now U.S. Pat. No. 7,198,119, which is a continuation-in-part of U.S. patent application Ser. No. 11/164,391, filed Nov. 21, 2005, now U.S. Pat. No. 7,270,196. This patent application is also a continuation-in-part of U.S. patent application Ser. No. 11/555,334 which was filed on Nov. 1, 2006, now U.S. Pat. No. 7,419,018. All of these applications are herein incorporated by reference in their entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    This invention relates to the field of downhole drill strings. Increasing the rate of penetration in drilling saves substantial amount of time and money in the oil and gas, geothermal, exploration, and horizontal drilling industries. 
         [0003]    U.S. Pat. No. 6,588,518 to Eddison, which is herein incorporated by reference for all that it contains, discloses a downhole drilling method comprising the production of pressure pulses in drilling fluid using measurement-while-drilling (MWD) apparatus and allowing the pressure pulses to act upon a pressure responsive device to create an impulse force on a portion of the drill string. 
         [0004]    U.S. Pat. No. 4,890,682 to Worrall, et al., which is herein incorporated by reference for all that it contains, discloses a jarring apparatus provided for vibrating a pipe string in a borehole. The apparatus thereto generates at a downhole location longitudinal vibrations in the pipe string in response to flow of fluid through the interior of said string. 
         [0005]    U.S. Pat. No. 4,979,577 to Walter et al., which is herein incorporated by reference for all that it contains, discloses a flow pulsing apparatus adapted to be connected in a drill string above a drill bit. The apparatus includes a housing providing a passage for a flow of drilling fluid toward the bit. A valve which oscillates in the axial direction of the drill string periodically restricts the flow through the passage to create pulsations in the flow and a cyclical water hammer effect thereby to vibrate the housing and the drill bit during use. Drill bit induced longitudinal vibrations in the drill string can be used to generate the oscillation of the valve along the axis of the drill string to effect the periodic restriction of the flow or, in another form of the invention, a special valve and spring arrangement is used to help produce the desired oscillating action and the desired flow pulsing action. 
       BRIEF SUMMARY OF THE INVENTION 
       [0006]    In one aspect of the invention, a downhole tool string component comprises a fluid passageway formed between a first and second end. A valve mechanism is disposed within the fluid passageway adapted to substantially cyclically build-up and release pressure within the fluid passageway such that a pressure build-up results in radial expansion of at least a portion of the fluid passageway and wherein a pressure release results in a contraction of the portion of the fluid passageway. The valve mechanism disposed within the fluid passageway comprises a spring. Expansion and contraction of the portion of the fluid passageway assisting in advancing the drill string within a subterranean environment. This advancing may be accomplished by varying a weight loaded to a drill bit disposed or helping to propel the drill string along a horizontal well. 
         [0007]    The spring is adapted to oppose the travel of a fluid flow. The spring is a tension spring or a compression spring. The spring is disposed intermediate a carrier and a centralizer and is aligned coaxially with the downhole tool string component. The valve mechanism comprises a shaft radially supported by a bearing and the centralizer. The carrier is mounted to the shaft. The centralizer is adapted to align the shaft coaxially with the downhole tool string component. The bearing is disposed intermediate the shaft and the centralizer. The carrier comprises at least one port. The carrier comprises a first channel formed on a peripheral edge substantially parallel with an axis of the tool string component. 
         [0008]    The drilling fluid is adapted to push against a fluid engaging surface disposed on the carrier. The valve mechanism comprises an insert disposed intermediate and coaxially with the first end and the carrier. The centralizer and the insert are fixed within the fluid passageway. The insert comprises a taper adapted to concentrate the flow of the downhole tool string fluid into the carrier. The engagement of the fluid against the carrier resisted by the spring of the valve mechanism causes the first and second set of ports to align and misalign by oscillating the shaft. The insert further comprises a second channel on its peripheral edge. The valve mechanism comprises a fluid by-pass. The bit is adapted to cyclically apply pressure to the formation. The drill bit comprises a jack element with a distal end protruding from a front face of the drill bit and substantially coaxial with the axis of rotation of the bit. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a perspective diagram of an embodiment of a string of downhole tools suspended in a borehole. 
           [0010]      FIG. 2  is a cross-sectional diagram of an embodiment of a downhole tool string component. 
           [0011]      FIG. 3   a  is a cross-sectional diagram of another embodiment of a downhole tool string component. 
           [0012]      FIG. 3   b  is a cross-sectional diagram of another embodiment of a downhole tool string component. 
           [0013]      FIG. 4  is a cross-sectional diagram of an embodiment of a downhole tool string component with a drill bit. 
           [0014]      FIG. 5  is a cross-sectional diagram of another embodiment of a downhole tool string. 
           [0015]      FIG. 6  is a cross-sectional diagram of another embodiment of a downhole tool string. 
           [0016]      FIG. 7  is a perspective diagram of a tubular assembly. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]      FIG. 1  is a perspective diagram of an embodiment of a string of downhole tools  100  suspended by a derrick  101  in a borehole  102 . A bottomhole assembly  103  may be located at the bottom of the borehole  102  and may comprise a drill bit  104 . As the drill bit  104  rotates downhole the tool string  100  may advance farther into the earth. The drill string  100  may penetrate soft or hard subterranean formations  105 . The bottom hole assembly  103  and/or downhole components may comprise data acquisition devices which may gather data. The data may be sent to the surface via a transmission system to a data swivel  106 . The data swivel  106  may send the data to the surface equipment. Further, the surface equipment may send data and/or power to downhole tools and/or the bottom-hole assembly  103 . In some embodiments of the invention, no downhole telemetry system is used. 
         [0018]      FIG. 2  is a cross-sectional diagram of an embodiment of a downhole tool string component  200  comprised of a first end  210  and a second end  211 . The fluid passageway  201  may comprise a valve mechanism  202 . The valve mechanism  202  may comprise a shaft  203  aligned coaxially with the downhole tool string component  200  by a centralizer  218 . The valve mechanism  202  may also comprise a fluid by-pass  204 . The valve mechanism  202  may also comprise a spring  205  adapted to oppose the travel of a fluid flow. The drilling fluid may follow a path indicated by the arrows  233 . The spring  205  may be aligned coaxially with the downhole tool string component  200  and may be a compression spring or a tension spring. The valve mechanism  202  may also comprise a carrier  206  comprised of ports  220  and a first channel  221 . The valve mechanism  202  may also comprise an insert  207  disposed coaxially with the axis of the downhole tool string component  200 . The insert  207  may comprise a set of ports  222  and a second channel  223 . The insert  207  may comprise a taper  208  adapted to concentrate the flow of the drilling fluid into the carrier  206 . The spring  205  may be adapted to resist the engagement of the fluid flow against the carrier  206 . Without the fluid flow the ports may be misaligned due to the force of the spring. Once flow is added, the misaligned ports may obstruct the flow causing a pressure build-up. As the pressure increases the force of the spring may be overcome and eventual align the ports. Once the ports are aligned, the flow may pass through the ports relieving the pressure build-up such that the spring moves the carrier to misalign the ports. This cycle of aligning and misaligning the carrier ports  220  and insert ports  222  aids in the advancing the drill string within its subterranean environments. As both sets of ports  220 ,  222  are misaligned, the pressure build up from the drilling fluid may cause the wall  230  of the downhole drill string component  200  to expand. As both sets of ports  220 ,  222  are aligned, the pressure build up from the drilling fluid may be released as the drilling fluid is allowed to flow from the first channel  221 , through the ports  220 ,  222  and into the second channel  223 . The shaft  203  and carrier  206  may be secured to each other by means of press-fitting the shaft  203  into the carrier  206  or shrink fitting the carrier  206  over the shaft  203 . The shaft  203  may be allowed to move axially by a bearing  235  disposed intermediate the centralizer  218  and shaft  203 . 
         [0019]      FIG. 3   a  shows a cross-sectional diagram of another embodiment of a downhole tool string component  200 . With the ports  220  on the carrier  206  misaligned in relation to the ports  222  on the insert  207 , the drilling fluid is allowed to build up within the fluid passageway  201  causing the walls  230  of the downhole drill string component  200  to expand radially outward. 
         [0020]      FIG. 3   b  shows a cross-sectional diagram of another embodiment of a downhole tool string component  200 . With the ports  220  on the carrier  206  aligned with the ports  222  on the insert  207 , the drilling fluid is allowed to pass from the first end  210  to the second end  211  (shown in  FIG. 2 ), thus releasing the build up of pressure within the fluid passageway  201  and allowing the walls  230  of the downhole drill string component  200  to contract. As the pipe radially contracts, the pipe is believed to expand axially. This axial expansion is believed to increase the weight loaded to the drill bit and transfer a pressure wave into the formation. In some embodiments, the pressure relief above the valve will increase the pressure below the valve thereby pushing against the drill bit, further increasing the weight loaded to the drill bit. Also in some embodiments the affect of the oscillating valve&#39;s mass will fluctuate the weight loaded to the drill bit. 
         [0021]      FIG. 4  shows a cross-sectional diagram of a downhole drill string component  200  with a drill bit  340 . The drill bit  340  may be made in two portions. The first portion  305  may comprise at least the shank  300  and a part of the bit body  301 . The second portion  310  may comprise the working face  302  and at least another part of the bit body  301 . The two portions  305 ,  310  may be welded together or otherwise joined together at a joint  315 . 
         [0022]      FIG. 5  shows a perspective diagram of another embodiment of a downhole tool string component  200 . In this embodiment, the downhole tool string component  200  may comprise a valve mechanism  202 . The valve mechanism  202  may comprise a carrier  206  which may be comprised of at least one hole  405  disposed on the carrier  206 . The at least one hole  405  may be disposed offset at least one port  410  disposed on a guide  411  such that drilling fluid is unable to pass from the first end  210  to second end  211  if the carrier  206  is against the guide  411 . The drilling fluid may follow the path indicated by the arrow  233 . The guide  411  may be secured to the walls  230  of the downhole drill string component  200  and may serve to align the shaft  203  axially with the downhole drill string component  200 . A bearing  235  may be disposed intermediate the carrier  206  and the wall  230  of the downhole drill string component  200 . The valve mechanism  202  may also comprise an insert  207  disposed intermediate the wall  230  of the downhole drill string component  200  and the shaft  203 . A spring  205  may be disposed intermediate the insert  207  and the carrier  206  and coaxially with the downhole drill string component  200 . 
         [0023]      FIG. 6  shows a perspective diagram of another embodiment of a downhole tool string component  200 . In this embodiment, the valve mechanism  202  may comprise a spring  205  disposed intermediate a carrier  206  and insert  207  and coaxially with the downhole tool string component  200 . The insert  207  may comprise a set of ports  610  and a bearing  612  disposed intermediate a shaft  203  and the insert  207 . The drilling fluid may follow the path indicated by the arrow  233 . 
         [0024]      FIG. 7  is a perspective diagram of a tubular assembly  2000  penetrating into a subterranean environment  2001 . Preferable the tubular assembly  200  is a drill string  100  which comprises a bore for the passing drilling mud through. The tubular assembly may comprise a mechanism for contracting and expanding a diameter of the tubular assembly such that a wave is generated which travels of the tubular assembly. This mechanism may be a valve mechanism such as the valve mechanism described in  FIG. 2 . In horizontal drilling applications the length  2003  of the tubular assembly may be engaged with the bore wall and waves  2002  may aid in moving the tubular assembly in its desired trajectory. In some embodiments of the present invention, the tubular assembly is not rotated such as in traditionally oil and gas exploration, but is propelling along its trajectory through the waves  2002 . 
         [0025]    The tubular assembly may be used in oil and gas drilling, geothermal operations, exploration, and horizontal drilling such as for utility lines, coal methane, natural gas, and shallow oil and gas. 
         [0026]    In one aspect of the present invention a method for penetrating a subterranean environment includes the steps of providing a tubular assembly with a oscillating valve mechanism disposed within its bore, the valve mechanism comprising the characteristic such that as a fluid is passing through the valve, the valve will oscillate between an open and closed position; generating a wave along a length of the tubular assembly by radially expanding and contracting the tubular assembly by increasing and decreasing a fluid pressure by oscillating the valve mechanism; and engaging the length the tubular assembly such that the wave moves the tubular assembly along a trajectory. 
         [0027]    In another aspect of the present invention a method for penetrating a subterranean environment comprises the steps of providing a tubular assembly with a mechanism disposed within its bore adapted to expand and contract a diameter of the tubular assembly; generating a wave along a length of the tubular assembly by radially expanding and contracting a diameter of the tubular assembly; and engaging the length the tubular assembly such that the wave moves the tubular assembly along a trajectory. 
         [0028]    Whereas the present invention has been described in particular relation to the drawings attached hereto, it should be understood that other and further modifications apart from those shown or suggested herein, may be made within the scope and spirit of the present invention.