Raise bore drilling machine

Claim 2

In a method of raise bore drilling in which a drill string extends in a pilot hole between a raise bore drilling bit at the lower end of the pilot hole and a drill string drive means above and adjacent the upper end of the pilot hole, the drill string drive means including means operable for applying torque and axial tension to the drill string while affording axial motion of the drill string, the improvement comprising using a drill string which is non-round, except at spaced periodic locations along the elongate extent of the drill string, for transmitting torque and axial tension from the drive means to the bit.

Claim 3

In a raise bore drilling method according to claim 1 in which the drive means is operable for rotating the drill string about its axis to apply torque to the raise bore drilling bit via the drill string and for applying an axial tensile load to the drill string which is composed of a plurality of non-round individual drill string lengths, and in which the method includes the steps of operating the drive means to rotate the drill string and to raise the drill string until a connection in the string between individual lengths thereof is accessible at the drive means, locking the drive means from rotation of the drill string about its axis while maintaining engagement of the drive means below the connection with the non-round drill string to prevent rotation of the drill string below the connection, and disconnecting from the upper end of the non-round drill string at least one individual length thereof, the improvement which comprises the further steps of providing holding apparatus in the drive means, separate from the portions of the drive means operable for applying torque and an axial tensile load to the drill string in the drive means, and operating the holding apparatus before performing the disconnecting step.

Claim 4

In a method of raise bore drilling according to claim 1 wherein at least some of the individual drill string lengths have a circularly cylindrical portion adjacent one end of the length and are of regular polygonal cross-section along the remainder major portion of the length thereof, the diameter of the cylindrical portion being at least as great as a diagonal of the polygonal cross-section, the drive means comprises rotary means drivable about the axis of the drill string and matable with the non-round exterior of the drill string for application of torque to the drill string while accommodating axial movement of the drill string, the drill string is composed of a plurality of threadably connected individual non-round drill string lengths, the rotary means includes a plurality of rollers engageable with the polygonal portion of a length for applying torque thereto and for accommodating axial motion thereof, the rollers being mounted to be driven about the drill string axis and for limited movement along but not about the axis, and the method includes the step of retracting the rollers away from the drill string to enable a cylindrical portion of a drill string length connection to pass through the rotary means.

Claim 5

In a method of raise bore drilling according to claim 1 wherein at least some of the individual drill string lengths have an externally round connection component at the one end thereof and are of regular polygonal cross-section along the remainder major portion of its length, the diameter of the round connection component being at least as great as a diagonal of the polygonal cross-section, the drive means comprises rotary means drivable about the axis of the drill string and matable with the non-round exterior of the drill string for application of torque to the drill string while accommodating axial movement of the drill string, and the method includes the step of expanding the rotary means to enable a round connection component to pass through the rotary means.

Claim 6

In a method of raise bore drilling according to claim 4, the further step of expanding the rotary means in the drive means.

Claim 7

In a method of raise bore drilling according to claim 5, the further step of expanding the rotary means without substantial alteration of the torque applying geometry of the rotary means.

Claim 8

In a method of raise bore drilling in which a drill string composed of individual drill string lengths extends in a pilot hole between a raise bore drilling bit at the lower end of the pilot hole and a drill string drive means above and adjacent the upper end of the pilot hole, and the drill string drive means including means operable for applying torque to the drill string while affording axial motion of the drill string therepast, the drill string being provided for transmitting torque and axial tension from the drive means to the raise bore drilling bit, the improvement comprising the steps of using a drill string which is of constant non-round cross-sectional configuration except adjacent locations at which individual drill string lengths are connected and at which locations the drill string is of increased cross-sectional configuration, providing as a component of the drive means a rotary means drivable about the axis of the drill string and matable with the non-round exterior of the drill string for application of torque to the drill string while accommodating axial movement of the drill string, and expanding the rotary means to enable one of said locations of the drill string to pass through the rotary means.

Claim 9

In a method of raise bore drilling in which a drill string composed of individual drill string lengths extends in a pilot hole between a raise bore drilling bit at the lower end of the pilot hole and a drill string drive means above and adjacent the upper end of the pilot hole, and the drill string drive means including means operable for applying torque to the drill string while affording axial motion of the drill string therepast, the drill string being provided for transmitting torque and axial tension from the drive means to the raise bore drilling bit, the improvement comprising the steps of using a drill string which is of constant non-round cross-sectional configuration except adjacent locations at which individual drill string lengths are connected and at which locations the drill string is of increased cross-sectional configuration, providing as a component of the drive means a rotary means drivable about the axis of the drill string and matable with the non-round exterior of the drill string for application of torque to the drill string while accommodating axial movement of the drill string, and expanding the rotary means to enable one of said locations of the drill string to pass through the rotary means.

Claim 12

The method of claim 8 which comprises the additional steps of a. terminating rotation of the drill string when the engaging means has contacted the cylindrical portion of the pipe length adjacent the pipe length engaged by the bushing and has moved a distance along the axis of the drill string at least as great as the length of the cylindrical portion, b. securing the bushing from rotation thereof about the axis, c. securing the drill string from movement axially through the bushing, and d. removing from the drill string any pipe lengths which extend entirely on the working area side of the bushing.

Claim 13

The method of claim 8 wherein each pipe length has a female connecting moiety at the end thereof at which the pipe length defines the cylindrical portion thereof, each pipe length having a male connecting moiety at its opposite end.

Claim 14

The method of claim 8 wherein the axial extent of each pipe length cylindrical portion is less than about twice the diameter of the cylindrical portion.

Claim 15

The method of claim 11 wherein the axial extent of each pipe length cylindrical portion is about as great as the diameter of the cylindrical portion.

Claim 16

A raise bore drilling rig for use with a drill string composed of a plurality of drill pipe lengths each having male and female torque and tension transmitting connection moieties at its opposite ends, having a non-round external cross-sectional configuration along at least a portion of the elongate extent thereof and being of increased cross-sectional area at the female end thereof, the rig comprising a rotary table having a drivable annular member rotatable about a vertical axis and through which the drill string can be raised along the axis during raise bore drilling, and torque transmitting means essentially permanently coupled to the annular member in use for rotation therewith and configured to mate with the drill string for transmitting torque from the annular member to the drill string and for accommodating axial movement of the drill string, including upward movement of a female connection moiety in the drill string effectively through a base position of the torque transmitting means relative to the annular member along the axis while maintaining torque transmitting engagement of the torque transmitting means with the drill string.

Claim 17

A raise bore drilling rig for use with a drill string composed of a plurality of drill pipe lengths each having male and female torque and tension transmitting connection moieties at its opposite ends, having a non-round external cross-sectional configuration along at least a portion of the elongate extent thereof and being of increased cross-sectional area at the female end thereof, the rig comprising a rotary table having a drivable annular member rotatable about a vertical axis and through which the drill string can be raised along the axis during raise bore drilling, and torque transmitting means essentially permanently coupled to the annular member in use for rotation therewith and configured to mate with the drill string for transmitting torque from the annular member to the drill string and for accommodating axial movement of the drill string, including upward movement of a female connection moiety in the drill string effectively through a base position of the torque transmitting means relative to the annular member along the axis while maintaining torque transmitting engagement of the torque transmitting means with the drill string.

Claim 18

A raise bore drilling rig for use with a drill string composed of a plurality of individual drill pipe lengths of non-round transverse external cross-section, the rig comprising a rotary table having a drivable annular member rotatable about a central vertical axis and through which the drill string can be raised during raise boring, and torque transmitting means essentially permanently mounted to the annular member in use for rotation therewith and including engaging means configured to mate with the non-round portion of the drill string for transmitting torque from the member to the drill string while accommodating axial movement of the drill string including movement of a connection in the drill string between adjacent pipe lengths effectively through a base position of the engaging means vertically relative to the annular member while maintaining torque transmitting engagement of the engaging means with the drill string.

Claim 19

A raise bore drilling rig for use with a drill string composed of a plurality of individual drill pipe lengths of non-round transverse external cross-section, the rig comprising a rotary table having a drivable annular member rotatable about a central vertical axis and through which the drill string can be raised during raise boring, and torque transmitting means essentially permanently mounted to the annular member in use for rotation therewith and including engaging means configured to mate with the non-round portion of the drill string for transmitting torque from the member to the drill string while accommodating axial movement of the drill string including movement of a connection in the drill string between adjacent pipe lengths effectively through a base position of the engaging means vertically relative to the annular member while maintaining torque transmitting engagement of the engaging means with the drill string.

Claim 20

A raise bore drilling rig according to claim 14 wherein the engaging means includes roller means disposed about the central axis and configured to mate with the non-round portion of the drill string for transmitting torque to the drill string while accommodating said axial movement thereof through the engaging means, and means mounting the roller means for movement toward and away from the central axis.

Claim 21

A raise bore drilling rig according to claim 14 including selectively operable holding means releasably engageable with a drill string in the torque transmitting means for holding the drill string from downward movement relative to the rotary table.

Claim 22

A raise bore drilling rig according to claim 16 wherein each of the pipe lengths has an upper end and defines, in the exterior thereof adjacent to and a selected distance from the upper end thereof, shoulder means opening toward the other end thereof, and the holding means is engageable with the shoulder means.

Claim 23

A raise bore drilling rig according to claim 16 wherein the holding means are provided separately from the torque transmitting means.

Claim 24

A raise bore drilling rig according to claim 16 wherein the holding means is engageable with a drill string at a location on the drill string below the torque transmitting means.

Claim 25

A raise bore drilling rig for use with a drill string composed of a plurality of individual pipe lengths each having male and female torque and axial load transmitting connection moieties at its opposite ends, each pipe length having a non-round cross-sectional configuration along the extent thereof from the male end thereof to a circularly cylindrical end portion at the female end thereof, the diameter of the cylindrical portion being at least as great as the greatest transverse dimension of the non-round portion of the pipe length, the rig comprising a. a rotary table having a drivable annular member rotatable about an axis and through which the drill string can be raised along the axis during raise bore drilling, b. torque transmitting means essentially permanently connected in use to the annular member for rotation therewith and configured to mate with the non-round portion of the drill string for transmitting torque from the annular member to the drill string and for accommodating axial movement of the drill string, including movement of a drill string cylindrical portion through a base position of the torque transmitting means relative to the annular member, while maintaining torque transmitting engagement with the drill string.

Claim 26

A raise bore drilling rig for use with a drill string composed of a plurality of individual pipe lengths each having male and female torque and axial load transmitting connection moieties at its opposite ends, each pipe length having a non-round cross-sectional configuration along the extent thereof from the male end thereof to a circularly cylindrical end portion at the female end thereof, the diameter of the cylindrical portion being at least as great as the greatest transverse dimension of the non-round portion of the pipe length, the rig comprising a. a rotary table having a drivable annular member rotatable about an axis and through which the drill string can be raised along the axis during raise bore drilling, b. torque transmitting means essentially permanently connected in use to the annular member for rotation therewith and configured to mate with the non-round portion of the drill string for transmitting torque from the annular member to the drill string and for accommodating axial movement of the drill string, including movement of a drill string cylindrical portion through a base position of the torque transmitting means relative to the annular member, while maintaining torque transmitting engagement with the drill string.

Claim 27

A raise bore drilling rig according to claim 20 wherein the holding means is engageable with a drill string at a location on the drill string below the torque transmitting means.

Claim 28

A raise bore drilling rig according to claim 20 wherein the torque transmitting means includes selectively operable means operable for effectively expanding the torque transmitting means to enable passage of a cylindrical portion of a pipe length axially therethrough.

Claim 29

A raise bore drilling rig according to claim 20 including selectively operable holding means mounted to the annular member and releasably engageable with a drill string disposed along the axis through the annular member for holding the drill string from downward movement relative to the annular member.

Claim 30

A raise bore drilling rig according to claim 23 wherein each pipe length, at the intersection of the cylindrical portion thereof with the non-round portion thereof, defines a shoulder facing along the pipe length toward the male end thereof, and the holding means is engageable with the shoulder.

Claim 31

A raise bore drilling rig according to claim 20 wherein the torque transmitting means includes roller means diposed about the axis for rotation with the annular member and configured to mate with the non-round portion of the drill string for transmitting torque to the drill string while accommodating axial movement thereof, and mounting means mounting the roller means for movement thereof from the base position thereof parallel to the axis by an amount related to the length of a drill string cylindrical portion along the drill string.

Claim 32

A raise bore drilling rig according to claim 25 wherein the non-round cross-sectional configuration of the drill string is that of a regular polygon and the roller means comprises a plurality of rollers profiled to mate with corresponding portions of the polygonal cross-section of the drill string.

Claim 33

A raise bore drilling rig according to claim 25 wherein the mounting means mounting the roller means includes means mounting the individual rollers for movement between a torque transmitting engaged position inwardly toward the axis and a retracted position outwardly of the engaged position thereof sufficiently for passage of a drill string cylindrical portion therepast.

Claim 34

A raise bore drilling rig according to claim 25 including selectively operable means coupled to the roller means and operable for moving the roller means parallel to the axis from the base position thereof by said amount.

Claim 35

A raise bore drilling rig according to claim 20 wherein the holding means are provided separately from the torque transmitting means.

Claim 36

A raise bore drilling rig according to claim 29 wherein the non-round cross-sectional configuration of the drill string is that of a regular polygon and the roller means comprises a plurality of rollers profiled to mate with corresponding portions of the polygonal cross-section of the drill string.

Claim 37

A raise bore drilling rig according to claim 29 wherein the mounting means mounting the roller means includes means mounting the individual rollers for movement between a torque transmitting engaged position inwardly toward the axis and a retracted position outwardly of the engaged position thereof sufficiently for passage of a drill string cylindrical portion therepast.

Claim 38

A raise bore drilling rig according to claim 29 including selectively operable means coupled to the roller means and operable for moving the roller means parallel to the axis from the base position thereof by said amount.

Claim 39

A raise bore drilling rig for use with a drill string composed of a plurality of individual pipe lengths of uniform regular polygonal transverse cross-sectional configuration except a portion at the upper end of each pipe length where the pipe length is of circularly cylindrical configuration for a selected distance along the pipe length which is related to the axial extent of a connection in the drill string between adjacent pipe lengths, the diameter of the cylindrical portion being at least as great as substantially the greatest diagonal of the polygonal cross-section, the rig comprising a rotary table having an annular member rotatable about a vertical axis corresponding to the rotational axis of the drill string, torque transmitting bushing means having an opening through which the drill string can pass and mounted to the annular member for rotation therewith with the opening thereof centered on the axis, the bushing means including a plurality of rollers configured to mate with the polygonal cross-section of the drill string for transmitting torque to the drill string from the annular member and for accommodating axial motion of the drill string through the bushing means, and means mounting the rollers for motion thereof from a base position of the rollers relative to the annular member vertically along but not angularly about the axis relative to the annular member by an amount related to the selected distance and for motion of the rollers outwardly from the axis between an inward position in which the rollers are matable in torque transmitting relation to the polygonal cross-sectional configuration of the drill string and an outward position, the rollers in their outward position being spaced from the inward position thereof sufficiently to provide clearance for passage of a connection in the drill string through the bushing means.

Claim 40

A raise bore drilling rig for use with a drill string composed of a plurality of individual pipe lengths of uniform regular polygonal transverse cross-sectional configuration except a portion at the upper end of each pipe length where the pipe length is of circularly cylindrical configuration for a selected distance along the pipe length which is related to the axial extent of a connection in the drill string between adjacent pipe lengths, the diameter of the cylindrical portion being at least as great as substantially the greatest diagonal of the polygonal cross-section, the rig comprising a rotary table having an annular member rotatable about a vertical axis corresponding to the rotational axis of the drill string, torque transmitting bushing means having an opening through which the drill string can pass and mounted to the annular member for rotation therewith with the opening thereof centered on the axis, the bushing means including a plurality of rollers configured to mate with the polygonal cross-section of the drill string for transmitting torque to the drill string from the annular member and for accommodating axial motion of the drill string through the bushing means, and means mounting the rollers for motion thereof from a base position of the rollers relative to the annular member vertically along but not angularly about the axis relative to the annular member by an amount related to the selected distance and for motion of the rollers outwardly from the axis between an inward position in which the rollers are matable in torque transmitting relation to the polygonal cross-sectional configuration of the drill string and an outward position, the rollers in their outward position being spaced from the inward position thereof sufficiently to provide clearance for passage of a connection in the drill string through the bushing means.

Claim 41

A raise bore drilling rig according to claim 33 wherein the polygonal cross-sectional configuration of the drill string is an equilateral hexagon, and the rollers comprise a pair of cylindrical rollers and a pair of biconical rollers.

Claim 42

A raise bore drilling rig according to claim 33 including means selectively operable for moving the rollers simultaneously between their inward and outward positions.

Claim 43

A raise bore drilling rig according to claim 33 including means selectively operable for moving the rollers concurrently between their inward and outward positions.

Claim 44

A raise bore drilling rig according to claim 33 wherein each pipe length defines shoulder means at the lower end of the cylindrical portion thereof, the shoulder means opening toward the lower end of the pipe length, and holding means in the bushing means selectively engageable with the shoulder means for holding the drill string from downward motion along the axis.

Claim 45

A raise bore drilling rig according to claim 37 wherein the holding means is configured to mate with the polygonal cross-sectional configuration of the drill string for securing the drill string from rotation about the axis relative to the bushing means.

Claim 46

A method of operating a raise bore drilling rig as defined in claim 38 for drilling a raise using the polygonal cross-sectionally configured drill string, the method comprising the steps of 1. connecting a swivel to the upper end of the drill string which extends through a raise pilot hole aligned with the axis and through the rotary table and which is connected at its lower end to a raise bore drilling bit, 2. disposing the rollers in the inward position thereof to mate the rollers in torque transmitting relation with the polygonal portion of the drill string pipe length extending through the bushing means, and a. rotating the annular member to apply to the drill string via the rollers sufficient torque to operate the bit, and b. raising the drill string via the swivel along said axis through the bushing means as the bit operates to form the raise while maintaining in the drill string a selected level of axial tension, 3. continuing the procedures according to step (2) until the cylindrical portion of the drill string immediately below the pipe length extending through the bushing means engages and raises the rollers said amount in the bushing means, 4. ceasing rotation of the annular member while holding the axial position of the drill string to maintain the selected tension level therein, 5. disposing the rollers in the outward position thereof for movement of the rollers downwardly in the bushing means to the base position thereof, 6. operating the holding means to mate with the polygonal cross-sectional configuration of the drill string below the drill string cylindrical portion immediately below the pipe length originally extending through the bushing means, thereby to secure the bushing means from rotation relative to the drill string, 7. gradually lowering the drill string to release torque and tension built up therein and then lowering the drill string in the bushing means until the shoulder means defined by the drill string cylindrical portion at the bushing means contacts the holding means for support of the drill string in the rotary table, 8. locking the annular member from rotation in the rotary table about said axis,

Claim 47

disconnecting the pipe length originally extending through the bushing means from the drill string and from the swivel and connecting the swivel to the drill string supported in the bushing means, 10. raising the drill string via the swivel through the bushing means to dispose the uppermost drill string cylindrical portion above the rollers, 11. disposing the rollers in the inward position thereof to mate the rollers in torque transmitting relation with the drill string polygonal cross-sectional configuration below the uppermost drill string cylindrical portion, 12. operating the holding means to move the same out of engagement with the drill string, 13. unlocking the annular member for rotation of the same in the rotary table about the axis, and 14. resuming performance of the procedures according to steps (2) (a) and (2) (b).

Claim 48

disconnecting the pipe length originally extending through the bushing means from the drill string and from the swivel and connecting the swivel to the drill string supported in the bushing means, 10. raising the drill string via the swivel through the bushing means to dispose the uppermost drill string cylindrical portion above the rollers, 11. disposing the rollers in the inward position thereof to mate the rollers in torque transmitting relation with the drill string polygonal cross-sectional configuration below the uppermost drill string cylindrical portion, 12. operating the holding means to move the same out of engagement with the drill string, 13. unlocking the annular member for rotation of the same in the rotary table about the axis, and 14. resuming performance of the procedures according to steps (2) (a) and (2) (b).

Claim 49

A raise bore drilling rig according to claim 33 including drive means selectively operable for driving the rollers along the axis from the base position thereof by said amount.

Claim 50

A raise bore drilling rig according to claim 40 including means operable for disabling the drive means in such manner as to minimize any impediment thereby to motion of the rollers along the axis.

Claim 51

A raise bore drilling rig according to claim 41 wherein the drive means comprises pneumatic means.

Claim 52

A raise bore drilling rig according to claim 42 wherein the disabling means includes a valve operable to provide communication between atmosphere and the pneumatic means for flow of air into and out of the pneumatic means in response to movement of the rollers along the axis by forces independent of the pneumatic means.

Claim 53

A raise bore drilling rig according to claim 43 wherein the bushing means comprises a lower plate fixed to the annular member and an upper plate aligned with the lower plate and substantially parallel thereto, the upper plate having the rollers mounted thereon, and wherein the means mounting the rollers for motion along but not angularly about the axis comprises guide means cooperating between the upper and lower plates.

Claim 54

A raise bore drilling rig according to claim 44 wherein the pneumatic means comprises an inflatable bladder disposed between the upper and lower plates.

Claim 55

A raise bore drilling rig according to claim 45 including spacer means cooperating between the upper and lower plates for defining a lowermost position of the upper plate in which the upper plate is spaced above the lower plate an amount greater than the vertical extent of the bladder in its uninflated state.

Claim 56

A method of operating a raise bore drilling rig as defined in claim 41 for drilling a hole downwardly using the polygonal cross-sectionally configured drill string, the method comprising the steps of 1. disposing the rollers in the inward position thereof to mate the rollers in torque transmitting relation with the polygonal portion of the drill string pipe length extending through the bushing means, and a. rotating the annular member to apply to the drill string via the rollers sufficient torque to operate a drill bit connected to the lower end of the drill string, and b. lowering the drill string along the axis through the bushing means as the drill bit operates to cut into a formation being drilled, 2. continuing the procedure according to step (1) until the cylindrical portion of the pipe length extending through the bushing means is lowered substantially into contact with the rollers, 3. ceasing rotation of the annular member, 4. connecting to the drill string an additional pipe length to extend the total length of the drill string, 5. disposing the rollers in the outward position thereof, 6. raising the rollers said amount along the drill string axis by operating the drive means,

Claim 57

disposing the rollers in the inward position thereof to mate the rollers in torque transmitting engagement with the polygonal cross-section portion of the additional pipe length above the drill string cylindrical portion passed by the rollers during performance of the procedure according to step (6), 8. disabling the drive means, and 9. repeating steps (1) (a), (1) (b), and (2), during the initial phases of which the rollers can move downward with the drill string cylindrical portion immediately therebelow and return to the base portion thereof.

Claim 58

disposing the rollers in the inward position thereof to mate the rollers in torque transmitting engagement with the polygonal cross-section portion of the additional pipe length above the drill string cylindrical portion passed by the rollers during performance of the procedure according to step (6), 8. disabling the drive means, and 9. repeating steps (1) (a), (1) (b), and (2), during the initial phases of which the rollers can move downward with the drill string cylindrical portion immediately therebelow and return to the base portion thereof.

Claim 59

The method according to claim 47 wherein the step of connecting to the drill string an additional pipe length includes the further steps of 1. securing the annular member from rotation about the axis, and 2. using the bushing means to hold the drill string from rotation about the axis.

Claim 60

A raise bore drilling rig for use with a drill string composed of a plurality of individual pipe lengths of uniform regular polygonal transverse cross-sectional configuration except a portion at the upper end of each pipe length where the pipe length is of circularly cylindrical configuration for a selected distance along the length related to the axial extent of a connection in the drill string between adjacent pipe lengths, the diameter of the cylindrical portion being at least substantially as great as the greatest diagonal of the polygonal cross-section, the rig comprising a rotary table having an annular member rotatable about a vertical axis corresponding to the rotational axis of the drill string, a derrick including a crown block substantially vertically positionable above the rotary table with the crown block disposed in alignment with said axis, a swivel connectible to the drill string via a cylindrical end of a drill string pipe length, a drawworks including a line for suspending the swivel in the drawworks from the crown block for movement of the swivel along said axis in response to operation of the drawworks, power source means for operating the rotary table to rotate the annular member about said axis and for operating the drawworks to raise and lower the swivel and to create axial tension in the drill string when the drill string is suspended from the swivel and extends along the axis through the annular member and through a raise pilot hole below the rotary table to a raise bit connected to the lower end of the drill string, torque transmitting bushing means having an opening through which the drill string can pass and mounted to the rotary table annular member for rotation therewith with the bushing means opening centered on the axis, the bushing means including a plurality of rollers configured to mate with the polygonal cross-section of the drill string for transmitting torque to the drill string from the annular member and for accommodating axial motion of the drill string through the bushing means, means mounting the rollers for motion thereof vertically along but not angularly about the axis relative to the annular member, from a base position of the rollers relative to the annular member, by an amount related to the selected distance and for motion of the rollers outwardly from the axis between an inward position in which the rollers are matable in torque transmitting relation to the polygonal cross-sectional configuration of the drill string and an outward position, the rollers in their outward position being spaced from the inward position thereof sufficiently to provide clearance for passage of a connection in the drill string through the bushing means, means selectively operable for moving the rollers concurrently between their inward and outward positions, and holding means carried by the rotary table selectively engageable with the lower end of the cylindrical portion of a drill string pipe length for holding the drill string from downward motion along the axis.

Claim 61

A raise bore drilling rig for use with a drill string composed of a plurality of individual pipe lengths of uniform regular polygonal transverse cross-sectional configuration except a portion at the upper end of each pipe length where the pipe length is of circularly cylindrical configuration for a selected distance along the length related to the axial extent of a connection in the drill string between adjacent pipe lengths, the diameter of the cylindrical portion being at least substantially as great as the greatest diagonal of the polygonal cross-section, the rig comprising a rotary table having an annular member rotatable about a vertical axis corresponding to the rotational axis of the drill string, a derrick including a crown block substantially vertically positionable above the rotary table with the crown block disposed in alignment with said axis, a swivel connectible to the drill string via a cylindrical end of a drill string pipe length, a drawworks including a line for suspending the swivel in the drawworks from the crown block for movement of the swivel along said axis in response to operation of the drawworks, power source means for operating the rotary table to rotate the annular member about said axis and for operating the drawworks to raise and lower the swivel and to create axial tension in the drill string when the drill string is suspended from the swivel and extends along the axis through the annular member and through a raise pilot hole below the rotary table to a raise bit connected to the lower end of the drill string, torque transmitting bushing means having an opening through which the drill string can pass and mounted to the rotary table annular member for rotation therewith with the bushing means opening centered on the axis, the bushing means including a plurality of rollers configured to mate with the polygonal cross-section of the drill string for transmitting torque to the drill string from the annular member and for accommodating axial motion of the drill string through the bushing means, means mounting the rollers for motion thereof vertically along but not angularly about the axis relative to the annular member, from a base position of the rollers relative to the annular member, by an amount related to the selected distance and for motion of the rollers outwardly from the axis between an inward position in which the rollers are matable in torque transmitting relation to the polygonal cross-sectional configuration of the drill string and an outward position, the rollers in their outward position being spaced from the inward position thereof sufficiently to provide clearance for passage of a connection in the drill string through the bushing means, means selectively operable for moving the rollers concurrently between their inward and outward positions, and holding means carried by the rotary table selectively engageable with the lower end of the cylindrical portion of a drill string pipe length for holding the drill string from downward motion along the axis.

Claim 62

A raise bore drilling rig according to claim 49 wherein the power source means comprises separate power sources for the rotary table and for the drawworks.

Claim 63

A raise bore drilling rig according to claim 49 wherein the derrick and the drawworks are mounted on a chassis separate from the rotary table.

Claim 64

A raise bore drilling rig according to claim 51 including a frame for the rotary table, and wherein the power source means comprises a power source for the rotary table mounted to the frame and a power source for the drawworks mounted to the chassis.

Claim 65

In a raise bore drilling rig for use with a drill string extending from a raise bore drilling bit into the rig, the drill string comprising a plurality of pipe lengths each having a non-round cross-sectional configuration along a major portion of the elongate extent of the pipe length and a circular cross-sectional configuration along a remainder portion of its elongate extent at the end thereof, whereby each pipe length has a cylindrical portion at one end thereof, the diameter of the cylindrical portion of each pipe length being at least substantially as great as the greatest transverse dimension of the non-round portion of the pipe length, the several pipe lengths being releasably interconnected in the drill string with the cylindrical portions thereof being the most remote end of each pipe length from the bit, the rig also comprising means connectible to the drill string for applying axial tension to the drill string along the longitudinal axis of the drill string, and a rotary table having a rotatable member through which the drill string can be moved along the longitudinal axis of the drill string, the improvement comprising a torque transmitting bushing essentially permanently connected in use to the rotatable member and having engaging means for engaging the non-round portion of the drill string in a torque applying relationship while at a base position thereof axially in the bushing and for accommodating axial movement of the non-round portion of the drill string therethrough while at the base position, the bushing also having means connected to the engaging means for accommodating movement of the engaging means from the base position along the longitudinal axis of the drill string, while the engaging means is in a torque applying relationship to the drill string, for a distance at least as great as the extent of a pipe length cylindrical portion axially of the pipe length, on contact of the cylindrical portion of an adjacent pipe length in the drill string with the engaging means.

Claim 66

In a raise bore drilling rig for use with a drill string extending from a raise bore drilling bit into the rig, the drill string comprising a plurality of pipe lengths each having a non-round cross-sectional configuration along a major portion of the elongate extent of the pipe length and a circular cross-sectional configuration along a remainder portion of its elongate extent at the end thereof, whereby each pipe length has a cylindrical portion at one end thereof, the diameter of the cylindrical portion of each pipe length being at least substantially as great as the greatest transverse dimension of the non-round portion of the pipe length, the several pipe lengths being releasably interconnected in the drill string with the cylindrical portions thereof being the most remote end of each pipe length from the bit, the rig also comprising means connectible to the drill string for applying axial tension to the drill string along the longitudinal axis of the drill string, and a rotary table having a rotatable member through which the drill string can be moved along the longitudinal axis of the drill string, the improvement comprising a torque transmitting bushing essentially permanently connected in use to the rotatable member and having engaging means for engaging the non-round portion of the drill string in a torque applying relationship while at a base position thereof axially in the bushing and for accommodating axial movement of the non-round portion of the drill string therethrough while at the base position, the bushing also having means connected to the engaging means for accommodating movement of the engaging means from the base position along the longitudinal axis of the drill string, while the engaging means is in a torque applying relationship to the drill string, for a distance at least as great as the extent of a pipe length cylindrical portion axially of the pipe length, on contact of the cylindrical portion of an adjacent pipe length in the drill string with the engaging means.

Claim 67

A torque transmitting bushing for cooperation with a component of a drill string, which component is of non-round transverse cross-sectional configuration, the bushing comprising a. a plurality of cooperating drive elements disposed about an axis of the bushing and configured to mate substantially circumferentially with the non-round configuration of the drill string component for application of torque to the component, b. carrier means carrying the drive elements and connectible to the rotary collar of a rotary table, for rotation therewith, to dispose the bushing axis in alignment with the axis of rotation of the rotary collar, c. means mounting the drive elements to the carrier means for movement along predetermined paths radially of the bushing axis, but not angularly about the bushing axis, into and out of an inward position of the drive elements in which the elements are disposed to mate with the non-round configuration of the drill string component, and d. selectively operable means operable for moving the drive elements substantially concurrently along their predetermined paths.

Claim 68

A torque transmitting bushing for cooperation with a component of a drill string, which component is of non-round transverse cross-sectional configuration, the bushing comprising a. a plurality of cooperating drive elements disposed about an axis of the bushing and configured to mate substantially circumferentially with the non-round configuration of the drill string component for application of torque to the component, b. carrier means carrying the drive elements and connectible to the rotary collar of a rotary table, for rotation therewith, to dispose the bushing axis in alignment with the axis of rotation of the rotary collar, c. means mounting the drive elements to the carrier means for movement along predetermined paths radially of the bushing axis, but not angularly about the bushing axis, into and out of an inward position of the drive elements in which the elements are disposed to mate with the non-round configuration of the drill string component, and d. selectively operable means operable for moving the drive elements substantially concurrently along their predetermined paths.

Claim 69

A bushing according to claim 54 wherein the selectively operable means is operable for moving the drive elements concurrently equal amounts along their respective predetermined paths.

Claim 70

A bushing according to claim 54 wherein the drive elements are rollers mounted to the carrier means for rotation about axes perpendicular to and spaced from the bushing axis.

Claim 71

A bushing according to claim 56 wherein the drill string component non-round cross-sectional configuration is that of a regular hexagon, and there are four rollers cooperatively profiled for mating with all six sides of the hexagon.

Claim 72

A torque transmitting bushing for cooperation with a component of a drill string, which component is of non-round transverse cross-sectional configuration, the bushing comprising a. a plurality of cooperating drive elements disposed about an axis of the bushing and configured to mate substantially circumferentially with the non-round configuration of the drill string component for application of torque to the component, b. carrier means carrying the drive elements and connectible to the rotary collar of a rotary table, for rotation therewith, to dispose the bushing axis in alignment with the axis of rotation of the rotary collar, c. means mounting the drive elements to the carrier means for movement along predetermined paths radially of the bushing axis, but not angularly about the bushing axis, into and out of an inward position of the drive elements in which the elements are disposed to mate with the non-round configuration of the drill string component, d. selectively operable means operable for moving the drive elements along their predetermined paths, and e. the carrier means includes means mounting the drive elements for motion as a group parallel to the bushing axis, but not angularly about the bushing axis within the bushing, between a base position and a displaced position.

Claim 73

A torque transmitting bushing for cooperation with a component of a drill string, which component is of non-round transverse cross-sectional configuration, the bushing comprising a. a plurality of cooperating drive elements disposed about an axis of the bushing and configured to mate substantially circumferentially with the non-round configuration of the drill string component for application of torque to the component, b. carrier means carrying the drive elements and connectible to the rotary collar of a rotary table, for rotation therewith, to dispose the bushing axis in alignment with the axis of rotation of the rotary collar, c. means mounting the drive elements to the carrier means for movement along predetermined paths radially of the bushing axis, but not angularly about the bushing axis, into and out of an inward position of the drive elements in which the elements are disposed to mate with the non-round configuration of the drill string component, d. selectively operable means operable for moving the drive elements along their predetermined paths, and e. the carrier means includes means mounting the drive elements for motion as a group parallel to the bushing axis, but not angularly about the bushing axis within the bushing, between a base position and a displaced position.

Claim 74

A raise bore drilling rig according to claim 58 including means operable for disabling the drive means in such manner as to minimize any substantial impediment thereby to motion of the rollers along the axis.

Claim 75

A bushing according to claim 58 wherein the selectively operable means is operable for moving the drive elements along their predetermined paths independently of the position of the drive elements along the axis.

Claim 76

A bushing according to claim 58 including drive means for moving the drive elements from their base position to their displaced position.

Claim 77

A bushing according to claim 61 wherein the drive means includes means operable for rendering the drive means passive so that the drive elements can be moved between their displaced and base positions by forces independent of the drive means without substantial restraint by the drive means.

Claim 78

A bushing according to claim 62 wherein the bushing includes a lower member, the carrier means comprises an upper member carrying the drive elements and mounted for movement between base and displaced positions thereof relative to the lower member parallel to the bushing axis, and the drive means is coupled between the upper and lower members.

Claim 79

A bushing according to claim 63 wherein the drive means comprises a pneumatic inflatable bladder engaged between the upper and lower members for moving the upper member along the bushing axis upon inflation thereof.

Claim 80

A bushing according to claim 64 wherein the members have openings therethrough along the bushing axis, and the bladder is annular and is disposed about the bushing axis outwardly of said openings.

Claim 81

A bushing according to claim 65 including closable means for selectively communicating the interior of the bladder to atmosphere.

Claim 82

A torque transmitting bushing for cooperation with a component of a drill string, which component is of non-round transverse cross-sectional configuration, the bushing comprising a. a plurality of cooperating drive elements disposed about an axis of the bushing and configured to mate substantially circumferentially with the non-round configuration of the drill string component for application of torque to the component, b. carrier means carrying the drive elements and connectible to the rotary collar of a rotary table, for rotation therewith, to dispose the bushing axis in alignment with the axis of rotation of the rotary collar, c. means mounting the drive elements to the carrier means for movement along predetermined paths radially of the bushing axis, but not angularly about the bushing axis, into and out of an inward position of the drive elements in which the elements are disposed to mate with the non-round configuration of the drill string component, d. selectively operable means operable for moving the drive elements along their predetermined paths, and e. holding means in the bushing movable into and out of an operated position in which the holding means is engageable with a drill string in the bushing for holding the drill string from moving downwardly along the bushing axis relative to the bushing.

Claim 83

A torque transmitting bushing for cooperation with a component of a drill string, which component is of non-round transverse cross-sectional configuration, the bushing comprising a. a plurality of cooperating drive elements disposed about an axis of the bushing and configured to mate substantially circumferentially with the non-round configuration of the drill string component for application of torque to the component, b. carrier means carrying the drive elements and connectible to the rotary collar of a rotary table, for rotation therewith, to dispose the bushing axis in alignment with the axis of rotation of the rotary collar, c. means mounting the drive elements to the carrier means for movement along predetermined paths radially of the bushing axis, but not angularly about the bushing axis, into and out of an inward position of the drive elements in which the elements are disposed to mate with the non-round configuration of the drill string component, d. selectively operable means operable for moving the drive elements along their predetermined paths, and e. holding means in the bushing movable into and out of an operated position in which the holding means is engageable with a drill string in the bushing for holding the drill string from moving downwardly along the bushing axis relative to the bushing.

Claim 84

A bushing according to claim 67 wherein the holding means is configured to register with the non-round configuration of the drill string component for holding the drill string from rotation about the bushing axis relative to the bushing independently of any similar rotation preventing operation of the drive elements.

Claim 85

A raise bore drilling rig for use with a drill string composed of a plurality of drill pipe lengths each having male and female torque and tension transmitting connection moieties at its opposite ends, having a non-round external cross-sectional configuration along at least a portion of the elongate extent thereof and being of increased cross-sectional area at the female end thereof, the rig comprising a rotary table having a drivable annular member rotatable about a vertical axis and through which the drill string can be raised along the axis during raise bore drilling, and torque transmitting means connected to the annular member for rotation therewith and configured to mate with the drill string for transmitting torque from the annular member to the drill string and for accommodating axial movement of the drill string while maintaining torque transmitting engagement of the torque transmitting means with the drill string, the torque transmitting means being expansible in place as connected to the annular member for accommodating movement of a female connection moiety in the drill string effectively through a base position of the torque transmitting means relative to the annular member along the axis and upwardly past the torque transmitting means.

Claim 86

A raise bore drilling rig for use with a drill string composed of a plurality of drill pipe lengths each having male and female torque and tension transmitting connection moieties at its opposite ends, having a non-round external cross-sectional configuration along at least a portion of the elongate extent thereof and being of increased cross-sectional area at the female end thereof, the rig comprising a rotary table having a drivable annular member rotatable about a vertical axis and through which the drill string can be raised along the axis during raise bore drilling, and torque transmitting means connected to the annular member for rotation therewith and configured to mate with the drill string for transmitting torque from the annular member to the drill string and for accommodating axial movement of the drill string while maintaining torque transmitting engagement of the torque transmitting means with the drill string, the torque transmitting means being expansible in place as connected to the annular member for accommodating movement of a female connection moiety in the drill string effectively through a base position of the torque transmitting means relative to the annular member along the axis and upwardly past the torque transmitting means.

Claim 87

A raise bore drilling rig for use with a drill string composed of a plurality of individual drill pipe lengths of non-round transverse external cross-section, the rig comprising a rotary table having a drivable annular member rotatable about a central vertical axis and through which the drill string can be raised during raise boring, torque transmitting means mounted to the annular member for rotation therewith and including engaging means configured to mate with the non-round portion of the drill string for transmitting torque from the member to the drill string while accommodating axial movement of the drill string including movement of a connection in the drill string between adjacent pipe lengths effectively through a base position of the engaging means vertically relative to the annular member while maintaining torque transmitting engagement of the engaging means with the drill string, the engaging means including roller means disposed about the central axis and configured to mate with the non-round portion of the drill string for transmitting torque to the drill string while accommodating said axial movement thereof through the engaging means, and means mounting the roller means for movement toward and away from the central axis.

Claim 88

A raise bore drilling rig for use with a drill string composed of a plurality of individual drill pipe lengths of non-round transverse external cross-section, the rig comprising a rotary table having a drivable annular member rotatable about a central vertical axis and through which the drill string can be raised during raise boring, torque transmitting means mounted to the annular member for rotation therewith and including engaging means configured to mate with the non-round portion of the drill string for transmitting torque from the member to the drill string while accommodating axial movement of the drill string including movement of a connection in the drill string between adjacent pipe lengths effectively through a base position of the engaging means vertically relative to the annular member while maintaining torque transmitting engagement of the engaging means with the drill string, the engaging means including roller means disposed about the central axis and configured to mate with the non-round portion of the drill string for transmitting torque to the drill string while accommodating said axial movement thereof through the engaging means, and means mounting the roller means for movement toward and away from the central axis.

Claim 89

A raise bore drilling rig for use with a drill string composed of a plurality of individual drill pipe lengths of non-round transverse external cross-section, the rig comprising a rotary table having a drivable annular member rotatable about a central vertical axis and through which the drill string can be raised during raise boring, torque transmitting means mounted to the annular member for rotation therewith and including engaging means configured to mate with the non-round portion of the drill string for transmitting torque from the member to the drill string while accommodating axial movement of the drill string including movement of a connection in the drill string between adjacent pipe lengths effectively through a base position of the engaging means vertically relative to the annular member while maintaining torque transmitting engagement of the engaging means with the drill string, and selectively operable holding means releasably engageable with a drill string in the torque transmitting means for holding the drill string from downward movement relative to the rotary table, the holding means being mounted to the annular member and being provided separately from the torque transmitting means.

Claim 90

A raise bore drilling rig for use with a drill string composed of a plurality of individual drill pipe lengths of non-round transverse external cross-section, the rig comprising a rotary table having a drivable annular member rotatable about a central vertical axis and through which the drill string can be raised during raise boring, torque transmitting means mounted to the annular member for rotation therewith and including engaging means configured to mate with the non-round portion of the drill string for transmitting torque from the member to the drill string while accommodating axial movement of the drill string including movement of a connection in the drill string between adjacent pipe lengths effectively through a base position of the engaging means vertically relative to the annular member while maintaining torque transmitting engagement of the engaging means with the drill string, and selectively operable holding means releasably engageable with a drill string in the torque transmitting means for holding the drill string from downward movement relative to the rotary table, the holding means being mounted to the annular member and being provided separately from the torque transmitting means.

Claim 91

A raise bore drilling rig according to claim 71 wherein the holding means is engageable with the drill string at a location on the drill string below the torque transmitting means.

Claim 92

A raise bore drilling rig for use with a drill string composed of a plurality of individual pipe lengths each having male and female torque and axial load transmitting connection moieties at its opposite ends, each pipe length having a non-round cross-sectional configuration along the extent thereof from the male end thereof to a circularly cylindrical end portion at the female end thereof, the diameter of the cylindrical portion being at least as great as the greatest transverse dimension of the non-round portion of the pipe lengths, the rig comprising a. a rotary table having a drivable annular member rotatable about an axis and through which the drill string can be raised along the axis during raise bore drilling, b. torque transmitting means connected to the annular member for rotation therewith and configured to mate with the non-round portion of the drill string for transmitting torque from the annular member to the drill string and for accommodating axial movement of the drill string, including movement of a drill string cylindrical portion through a base position of the torque transmitting means relative to the annular member, while maintaining torque transmitting engagement with the drill string, c. the torque transmitting means including roller means disposed about the axis for rotation with the annular member and configured to mate with the non-round portion of the drill string for transmitting torque to the drill string while accommodating axial movement thereof, and d. mounting means mounting the roller means for movement thereof from the base position thereof parallel to the axis by an amount related to the length of a drill string cylindrical portion along the drill string.

Claim 93

A raise bore drilling rig for use with a drill string composed of a plurality of individual pipe lengths each having male and female torque and axial load transmitting connection moieties at its opposite ends, each pipe length having a non-round cross-sectional configuration along the extent thereof from the male end thereof to a circularly cylindrical end portion at the female end thereof, the diameter of the cylindrical portion being at least as great as the greatest transverse dimension of the non-round portion of the pipe lengths, the rig comprising a. a rotary table having a drivable annular member rotatable about an axis and through which the drill string can be raised along the axis during raise bore drilling, b. torque transmitting means connected to the annular member for rotation therewith and configured to mate with the non-round portion of the drill string for transmitting torque from the annular member to the drill string and for accommodating axial movement of the drill string, including movement of a drill string cylindrical portion through a base position of the torque transmitting means relative to the annular member, while maintaining torque transmitting engagement with the drill string, c. the torque transmitting means including roller means disposed about the axis for rotation with the annular member and configured to mate with the non-round portion of the drill string for transmitting torque to the drill string while accommodating axial movement thereof, and d. mounting means mounting the roller means for movement thereof from the base position thereof parallel to the axis by an amount related to the length of a drill string cylindrical portion along the drill string.

Claim 94

A raise bore drilling rig for use with a drill string composed of a plurality of individual pipe lengths each having male and female torque and axial load transmitting connection moieties at its opposite ends, each pipe length having a non-round cross-sectional configuration along the extent thereof from the male end thereof to a circularly cylindrical end portion at the female end thereof, the diameter of the cylindrical portion being at least as great as the greatest transverse dimension of the non-round portion of the pipe length, the rig comprising a. a rotary table having a drivable annular member rotatable about an axis and through which the drill string can be raised along the axis during raise bore drilling, b. torque transmitting means connected to the annular member for rotation therewith and configured to mate with the non-round portion of the drill string for transmitting torque from the annular member to the drill string and for accommodating axial movement of the drill string, including movement of a drill string cylindrical portion through a base position of the torque transmitting means relative to the annular member, while maintaining torque transmitting engagement with the drill string, and c. selectively operable holding means mounted to the annular member effectively separately from the torque transmitting means and releasably engageable with a drill string disposed along the axis through the annular member for holding the drill string from downward movement relative to the annular member.

Claim 95

A raise bore drilling rig for use with a drill string composed of a plurality of individual pipe lengths each having male and female torque and axial load transmitting connection moieties at its opposite ends, each pipe length having a non-round cross-sectional configuration along the extent thereof from the male end thereof to a circularly cylindrical end portion at the female end thereof, the diameter of the cylindrical portion being at least as great as the greatest transverse dimension of the non-round portion of the pipe length, the rig comprising a. a rotary table having a drivable annular member rotatable about an axis and through which the drill string can be raised along the axis during raise bore drilling, b. torque transmitting means connected to the annular member for rotation therewith and configured to mate with the non-round portion of the drill string for transmitting torque from the annular member to the drill string and for accommodating axial movement of the drill string, including movement of a drill string cylindrical portion through a base position of the torque transmitting means relative to the annular member, while maintaining torque transmitting engagement with the drill string, and c. selectively operable holding means mounted to the annular member effectively separately from the torque transmitting means and releasably engageable with a drill string disposed along the axis through the annular member for holding the drill string from downward movement relative to the annular member.

Claim 96

A raise bore drilling rig for use with a drill string composed of a plurality of individual pipe lengths each having male and female torque and axial load transmitting connection moieties at its opposite ends, each pipe length having a non-round cross-sectional configuration along the extent thereof from the male end thereof to a circularly cylindrical end portion at the female end thereof, the diameter of the cylindrical portion being at least as great as the greatest transverse dimension of the non-round portion of the pipe length, the rig comprising a. a rotary table having a drivable annular member rotatable about an axis and through which the drill string can be raised along the axis during raise bore drilling, b. torque transmitting means connected to the annular member for rotation therewith and configured to mate with the non-round portion of the drill string for transmitting torque from the annular member to the drill string and for accommodating axial movement of the drill string, including movement of a drill string cylindrical portion through a base position of the torque transmitting means relative to the annular member, while maintaining torque transmitting engagement with the drill string, c. the torque transmitting means including selectively operable means operable for effectively expanding the torque transmitting means to enable passage of a cylindrical portion of a pipe length axially therethrough.

Claim 97

A raise bore drilling rig for use with a drill string composed of a plurality of individual pipe lengths each having male and female torque and axial load transmitting connection moieties at its opposite ends, each pipe length having a non-round cross-sectional configuration along the extent thereof from the male end thereof to a circularly cylindrical end portion at the female end thereof, the diameter of the cylindrical portion being at least as great as the greatest transverse dimension of the non-round portion of the pipe length, the rig comprising a. a rotary table having a drivable annular member rotatable about an axis and through which the drill string can be raised along the axis during raise bore drilling, b. torque transmitting means connected to the annular member for rotation therewith and configured to mate with the non-round portion of the drill string for transmitting torque from the annular member to the drill string and for accommodating axial movement of the drill string, including movement of a drill string cylindrical portion through a base position of the torque transmitting means relative to the annular member, while maintaining torque transmitting engagement with the drill string, c. the torque transmitting means including selectively operable means operable for effectively expanding the torque transmitting means to enable passage of a cylindrical portion of a pipe length axially therethrough.

Claim 98

A raise bore drilling rig according to claim 75 wherein the selectively operable means is arranged for expansion thereof in place as connected to the annular member.

Claim 99

A raise bore drilling rig for use with a drill string composed of a plurality of individual pipe lengths of uniform regular polygonal transverse cross-sectional configuration except a portion at the upper end of each pipe length where the pipe length is of increased cross-sectional area for a selected distance along the length related to the axial extent of a connection in the drill string between adjacent pipe lengths, the rig comprising a rotary table having an annular member rotatable about a vertical axis corresponding to the rotational axis of the drill string, a plurality of rollers configured to mate with the polygonal cross-section of the drill string for transmitting torque to the drill string from the annular member and for accommodating axial motion of the drill string therepast, means mounting the rollers to the annular member for torque transmitting engagement of the rollers with the drill string and for motion of the rollers vertically along but not angularly about the axis relative to the annular member, from a base position of the rollers relative to the annular member, by an amount related to the selected distance and for motion of the rollers outwardly from the axis, and drive means coupled to the rollers and selectively operable for driving the rollers along the axis from the base position thereof by said amount.

Claim 100

A raise bore drilling rig for use with a drill string composed of a plurality of individual pipe lengths of uniform regular polygonal transverse cross-sectional configuration except a portion at the upper end of each pipe length where the pipe length is of increased cross-sectional area for a selected distance along the length related to the axial extent of a connection in the drill string between adjacent pipe lengths, the rig comprising a rotary table having an annular member rotatable about a vertical axis corresponding to the rotational axis of the drill string, a plurality of rollers configured to mate with the polygonal cross-section of the drill string for transmitting torque to the drill string from the annular member and for accommodating axial motion of the drill string therepast, means mounting the rollers to the annular member for torque transmitting engagement of the rollers with the drill string and for motion of the rollers vertically along but not angularly about the axis relative to the annular member, from a base position of the rollers relative to the annular member, by an amount related to the selected distance and for motion of the rollers outwardly from the axis, and drive means coupled to the rollers and selectively operable for driving the rollers along the axis from the base position thereof by said amount.