Abstract:
A tubular downhole tool string component having a sidewall with a fluid passageway formed therein between a first end and second end, and a valve mechanism 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 sidewall and wherein a pressure release results in a radial contraction of the portion of the sidewall. The valve mechanism disposed within the fluid passageway comprises a spring. Radial expansion and contraction of the portion of the sidewall varies a weight loaded to a drill bit disposed at a drilling end of the drill string.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This Patent application is a continuation of U.S. patent application Ser. No. 12/039,635, filed on Feb. 28, 2008, now U.S. Pat. No. 7,967,082, 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 
     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. 
     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. 
     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. 
     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 
     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. 
     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. 
     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 
         FIG. 1  is a perspective diagram of an embodiment of a string of downhole tools suspended in a borehole. 
         FIG. 2  is a cross-sectional diagram of an embodiment of a downhole tool string component. 
         FIG. 3   a  is a cross-sectional diagram of another embodiment of a downhole tool string component. 
         FIG. 3   b  is a cross-sectional diagram of another embodiment of a downhole tool string component. 
         FIG. 4  is a cross-sectional diagram of an embodiment of a downhole tool string component with a drill bit. 
         FIG. 5  is a cross-sectional diagram of another embodiment of a downhole tool string. 
         FIG. 6  is a cross-sectional diagram of another embodiment of a downhole tool string. 
         FIG. 7  is a perspective diagram of a tubular assembly. 
     
    
    
     DETAILED DESCRIPTION 
       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. 
       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 central bore or 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 flow of drilling fluid. 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 sidewall  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 . 
       FIG. 3   a  shows a cross-sectional diagram of another embodiment of a downhole tool string component  200   a . With the ports  220   a  on the carrier  206   a  misaligned in relation to the ports  222   a  on the insert  207   a , the drilling fluid  233   a  is allowed to build up within the central bore or fluid passageway  201   a  causing the sidewalls  230   a  of the downhole drill string component  200   a  to expand radially outward. 
       FIG. 3   b  shows a cross-sectional diagram of another aspect of the embodiment of the downhole tool string component  200   a  showing in  FIG. 3   a . With the ports  220   a  on the carrier  206   a  aligned with the ports  222   a  on the insert  207   a , the drilling fluid is allowed to pass from the first end  210  to the second end  211   a , thus releasing the build up of pressure within the fluid passageway  201   a  and allowing the sidewalls  230   a  of the downhole drill string component  200   a  to radially contract back to their original position. 
     As the sidewall  230   a  of the downhole drill string component  200   a  or pipe radially contracts, the length of the downhole drill string component  200   a  or 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 mechanism  202   a  will increase the pressure below the valve mechanism  202   a  thereby pushing against the drill bit  104 , further increasing the weight loaded to the drill bit. Also in some embodiments the effect of the oscillating valve mechanism&#39;s mass will fluctuate the weight loaded to the drill bit. 
       FIG. 4  shows a cross-sectional diagram of a downhole drill string component  300  having a valve mechanism  360  installed within a drill bit  310 . The drill bit  310  may be made in two portions. The first portion  320  may comprise the shank  322 . The second portion  340  may comprise the working face  344  and the bit body  342 . The two portions  320 ,  340  may be welded together or otherwise joined together at a joint  315 . The drill bit  310  can further include a shaft  364  protruding out of its working face  344 , and which shaft  364  can also form a portion of the valve mechanism  360 . 
       FIG. 5  shows a perspective diagram of another embodiment of a downhole tool string component  400 . In this embodiment, the downhole tool string component  400  may comprise a valve mechanism  402 . The valve mechanism  402  may comprise a carrier  406  which may be comprised of at least one hole  420  disposed on the carrier  406 . The at least one hole  420  may be disposed offset at least one port  422  disposed on a guide  408  such that drilling fluid is unable to pass from the first end  410  to second end  411  if the carrier  406  is against the guide  408 . The drilling fluid may follow the path indicated by the arrow  433 . The guide  408  may be secured to the sidewalls  430  of the downhole drill string component  400  and may serve to align the shaft  403  axially with the downhole drill string component  400 . A bearing  435  may be disposed intermediate the carrier  406  and the sidewall  430  of the downhole drill string component  400 . The valve mechanism  402  may also comprise an insert  407  disposed intermediate the sidewall  430  of the downhole drill string component  400  and the shaft  403 . A spring  405  may be disposed intermediate the insert  407  and the carrier  406  and coaxially with the downhole drill string component  400 . 
       FIG. 6  shows a perspective diagram of another embodiment of a downhole tool string component  500 . In this embodiment, the valve mechanism  502  may comprise a spring  505  disposed intermediate a carrier  506  and insert  507  and coaxially with the downhole tool string component  500 . The insert  507  may comprise a set of ports  522  and a bearing  535  disposed intermediate a shaft  503  and the insert  507 . The drilling fluid may follow the path indicated by the arrow  533 . 
       FIG. 7  is a perspective diagram of a tubular assembly  600  penetrating into a subterranean environment  605 . Preferable the tubular assembly  600  is a drill string which comprises a central bore for the passing drilling mud through. The tubular assembly  600  may comprise a mechanism for contracting and expanding a diameter of the tubular assembly such that a wave is generated which travels a portion of the length of the tubular assembly. This mechanism may be a valve mechanism such as any of the valve mechanisms described in  FIGS. 2-6 . In horizontal drilling applications the length  602  of the tubular assembly  600  may be engaged with the wall of the well bore and waves  610  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  610 . 
     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. 
     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. 
     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. 
     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.