Primary transfer sub for dual concentric drillpipe

Claim 2

A fluid delivery and transfer unit for use with a dual string drillpipe having separate fluid passages for a downstream flow of energized fluid and for a combined upstream flow of exhaust fluid and entrained cuttings returns, and a downhole fluid-operated percussion motor having a downstream inlet fluid passage, said fluid delivery and transfer unit being adapted for removable attachment to the lower end of said drillpipe at its first end and to said percussion motor at the second end of said fluid delivery and transfer unit, comprising, in combination: i. an elongated metallic cylinder having downstream inlet and upstream outlet fluid passages at said first end thereof adapted for separate communication with said downstream and upstream fluid passages in said dual string drillpipe and having a single downstream outlet passage at said second end thereof adapted for communication with the downstream inlet fluid passage of said downhole percussion motor for delivery of energized fluid thereto; ii. ports means defined in the exterior of said cylinder communicating with the upstream outlet fluid passage at said first end of said elongated cylinder; iii. longitudinal passage mEans defined within said elongated cylinder communicating with said downstream inlet fluid passage at said first end of said elongated cylinder and with downstream outlet passage at said second end of said elongated cylinder; iv. first coupling means for removable connection of said elongated cylinder at said first end thereof to the distal end of said dual string drillpipe; v. second coupling means for removable connection of said elongated cylinder at said second end thereof to said downhole percussion motor.

Claim 3

A fluid delivery and transfer unit as disclosed in claim 1 wherein said first coupling means comprises: i. a tubular outer pipe box joint member secured to said first end of said cylinder coaxial therewith and having internal threads thereon; ii. a tubular inner pipe box joint member secured to said first end of said cylinder coaxial with and spaced from said outer pipe box joint member and having internal threads thereon, said outer pipe box joint member and said inner pipe box joint member thereby defining an annular fluid passage therebetween as said downstream inlet fluid passage and said inner pipe joint member defining a bore therein as said upstream outlet fluid passage.

Claim 4

A fluid delivery and transfer unit as disclosed in claim 2 wherein said second coupling means comprises a tubular pin joint member secured to said second end of said cylinder coaxial therewith and having external threads thereon, said tubular pin joint member defining a bore therein as said downstream outlet fluid passage.

Claim 5

A fluid delivery and transfer unit for use with a dual string drillpipe having separate fluid passages for a downstream flow of energized fluid and for a combined upstream flow of exhaust fluid and entrained cuttings returns, and a downhole fluid-operated percussion motor having a downsream inlet fluid passage, said fluid delivery and transfer unit being adapted for removable attachment to the lower end of said drillpipe at its first end and to said percussion motor at the second end of said fluid delivery and transfer unit, comprising, in combination: i. an elongated metallic cylindriform body portion having a longitudinal cylindriform body portion central bore communicating with an upstream fluid discharge outlet at a first end of said body portion and terminating in a blind bottom adjacent a second end of said body portion and thereby defining body portion sidewalls between said central bore and the external cylindriform surface of said body portion; ii. longitudinal downstream fluid passage means extending lengthwise through said body portion and isolated from said central bore; iii. a tubular outer pipe box joint member secured to said first end of said body portion coaxial therewith and having internal threads thereon; iv. a tubular inner pipe box joint member secured to said first end of said body portion coaxial with and spaced from said outer pipe box joint member and having internal threads thereon, said inner pipe box joint member defining an upstream fluid discharge outlet and a central bore communicating with said upstream fluid discharge outlet and with said body portion central bore, said outer pipe box joint member and said inner pipe box joint member thereby defining an annular downstream fluid passage therebetween; v. a tubular pin joint member secured to said second end of said body portion coaxial therewith and having external threads thereon, said tubular pin joint member defining a bore therein as said downstream outlet fluid passage, said outlet fluid passage communicating with said longitudinal downstream fluid passage means extending lengthwise through said body portion; and vi. port means defined in said body portion sidewalls and isolated from said longitudinal downstream fluid passage means and extending through said sidewalls for communication with said body portion central bore.

Claim 6

A fluid delivery and transfer unit for use with a dual string drillpipe having separate fluid passages for a downstream flow of energized fluid and for a combined upstream flow of exhaust fluid and entrained cuttings returns, and a downhole fluid-operated percussion motor having a downsream inlet fluid passage, said fluid delivery and transfer unit being adapted for removable attachment to the lower end of said drillpipe at its first end and to said percussion motor at the second end of said fluid delivery and transfer unit, comprising, in combination: i. an elongated metallic cylindriform body portion having a longitudinal cylindriform body portion central bore communicating with an upstream fluid discharge outlet at a first end of said body portion and terminating in a blind bottom adjacent a second end of said body portion and thereby defining body portion sidewalls between said central bore and the external cylindriform surface of said body portion; ii. longitudinal downstream fluid passage means extending lengthwise through said body portion and isolated from said central bore; iii. a tubular outer pipe box joint member secured to said first end of said body portion coaxial therewith and having internal threads thereon; iv. a tubular inner pipe box joint member secured to said first end of said body portion coaxial with and spaced from said outer pipe box joint member and having internal threads thereon, said inner pipe box joint member defining an upstream fluid discharge outlet and a central bore communicating with said upstream fluid discharge outlet and with said body portion central bore, said outer pipe box joint member and said inner pipe box joint member thereby defining an annular downstream fluid passage therebetween; v. a tubular pin joint member secured to said second end of said body portion coaxial therewith and having external threads thereon, said tubular pin joint member defining a bore therein as said downstream outlet fluid passage, said outlet fluid passage communicating with said longitudinal downstream fluid passage means extending lengthwise through said body portion; and vi. port means defined in said body portion sidewalls and isolated from said longitudinal downstream fluid passage means and extending through said sidewalls for communication with said body portion central bore.

Claim 7

A fluid delivery and transfer unit as disclosed in claim 4 in which said longitudinal downstream fluid Passage means comprise a plurality of longitudinal drillings extending lengthwise through said body portion sidewalls.

Claim 8

A fluid delivery and transfer unit as disclosed in claim 5 in which said longitudinal drillings are grouped for cross-sectional location within said sidewalls so that a substantial portion of the cross-sectional area of said sidewalls is unpenetrated by said drillings and is thereby available to accommodate said port means.

Claim 9

A fluid delivery and transfer unit as disclosed in claim 5 in which said longitudinal drillings are positioned for cross-sectional location within said sidewalls so as to define two groups of drillings, the walls of the most remote pair of members of each such group sub-tending an arc of the order of 90*.

Claim 10

A fluid delivery and transfer unit as disclosed in claim 5 in which said port means comprise port passages each having generally rectilinear cross-sectional configuration having substantially vertical port passage sidewalls each lying in a plane substantially tangential to the cylindriform body portion central bore and defining a generally rectilinear port entry opening on the outer cylindriform surface of said body portion and a generally rectilinear port discharge opening with said body portion central bore.

Claim 11

A fluid delivery and transfer unit as disclosed in claim 5 in which said port means comprise port passages each having generally rectilinear cross-sectional configuration having substantially vertical port passage sidewalls each lying in a plane substantially tangential to the cylindriform body portion central bore and having substantially planar port passage bottom and top walls each inclining upwardly and inwardly towards said body portion central bore and thereby defining with said port passage sidewalls a generally rectilinear port entry opening on the outer cylindriform surface of said body portion and a generally rectilinear port discharge opening with said body portion central bore.

Claim 12

A fluid delivery and transfer unit as disclosed in claim 5 in which said port means comprise port passages each having generally rectilinear cross-sectional configuration having substantially vertical port passage sidewalls each lying in a plane substantially tangential to the cylindriform body portion central bore and defining a generally rectilinear port entry opening on the outer cylindriform surface of said body portion and a generally rectilinear port discharge opening with said body portion central bore, said port entry opening and said port discharge opening having widths such that the arcs defined by the intersection of said port passage bottom and top walls with said external cylindriform surface of said body portion, and the intersection of said port passage bottom and top walls with said body portion central bore, each subtend approximately 62*.

Claim 13

A fluid delivery and transfer unit as disclosed in claim 5 in which said port means comprise port passages each having generally rectilinear cross-sectional configuration having substantially vertical port passage side walls each lying in a plane substantially tangential to the cylindriform body portion central bore and having substantially planar port passage bottom and top walls each inclining upwardly and inwardly towards said body portion central bore and thereby defining with said port passage sidewalls a generally rectilinear port entry opening on the outer cylindriform surface of said body portion and a generally rectilinear port discharge opening with said body portion central bore, said port entry opening and said port discharge opening having widths such that the arcs defined by the intersection of said port passage bottom and top walls with said external cylindriform surface of said body portion, and the intersection of said port passage bottom and top walls with said body portion central bore, each subtend approximately 62*.

Claim 14

A fluid delivery and transfer unit for use with a dual string drillpipe haVing separate fluid passages for a downstream flow of energized fluid and for a combined upstream flow of exhaust fluid and entrained cuttings returns defined by a pair of inner and outer concentric pipe members disposed in coaxial spaced relationship, such pipe members each terminating in an externally-threaded pin joint member similarly disposed in coaxial spaced relationship and having a substantially co-planar distal ends, said fluid delivery transfer unit being adapted for removeable thread-coupled attachment to the lower end of said dual string drillpipe, comprising in combination: i. an elongated metallic cylindriform body portion having a longitudinally extending cylindriform body portion central bore communicating with an upstream fluid discharge outlet at a first end of said body portion and terminating in a blind bottom adjacent a second end of said body portion and thereby defining body portion sidewalls between said central bore and the external cylindriform surface of said body portion; ii. longitudinal downstream fluid passage means extending lengthwise through said body portion and isolated from said central bore; iii. a tubular outer pipe box joint member secured to said first end of said body portion coaxial therewith and having internal threads thereon adapted to register with the external threads on said pin joint member of said outer concentric pipe member of said dual string drillpipe; iv. a tubular inner pipe box joint member secured to said first and of said body portion disposed coaxially with and spaced from said outer pipe box joint member so that the distal end of said inner pipe box joint member is substantially depressed below the distal end of said outer pipe box joint member, and having internal threads thereon adapted to register with the external threads on said pin joint member of said inner concentric pipe member of said dual string drillpipe, said inner pipe box joint member defining an upstream fluid discharge outlet and a central bore communicating with said upstream fluid discharge outlet and with said body portion central bore, said inner pipe box joint member and said outer pipe box joint member there by defining an annular downstream fluid passage therebetween; v. a tubular pin joint member secured to said second end of said body portion coaxial therewith and having external threads thereon, said tubular pin joint member defining a bore therein as said downstream outlet fluid passage, said outlet fluid passage communicating with said longitudinal downstream fluid passage means extending lengthwise through said body portion; vi. port means defined in said body portion sidewalls and isolated from said longitudinal downstream fluid passage means and extending through said sidewalls for communication with said body portion central bore.

Claim 15

A fluid delivery and transfer unit for use with a dual string drillpipe haVing separate fluid passages for a downstream flow of energized fluid and for a combined upstream flow of exhaust fluid and entrained cuttings returns defined by a pair of inner and outer concentric pipe members disposed in coaxial spaced relationship, such pipe members each terminating in an externally-threaded pin joint member similarly disposed in coaxial spaced relationship and having a substantially co-planar distal ends, said fluid delivery transfer unit being adapted for removeable thread-coupled attachment to the lower end of said dual string drillpipe, comprising in combination: i. an elongated metallic cylindriform body portion having a longitudinally extending cylindriform body portion central bore communicating with an upstream fluid discharge outlet at a first end of said body portion and terminating in a blind bottom adjacent a second end of said body portion and thereby defining body portion sidewalls between said central bore and the external cylindriform surface of said body portion; ii. longitudinal downstream fluid passage means extending lengthwise through said body portion and isolated from said central bore; iii. a tubular outer pipe box joint member secured to said first end of said body portion coaxial therewith and having internal threads thereon adapted to register with the external threads on said pin joint member of said outer concentric pipe member of said dual string drillpipe; iv. a tubular inner pipe box joint member secured to said first and of said body portion disposed coaxially with and spaced from said outer pipe box joint member so that the distal end of said inner pipe box joint member is substantially depressed below the distal end of said outer pipe box joint member, and having internal threads thereon adapted to register with the external threads on said pin joint member of said inner concentric pipe member of said dual string drillpipe, said inner pipe box joint member defining an upstream fluid discharge outlet and a central bore communicating with said upstream fluid discharge outlet and with said body portion central bore, said inner pipe box joint member and said outer pipe box joint member there by defining an annular downstream fluid passage therebetween; v. a tubular pin joint member secured to said second end of said body portion coaxial therewith and having external threads thereon, said tubular pin joint member defining a bore therein as said downstream outlet fluid passage, said outlet fluid passage communicating with said longitudinal downstream fluid passage means extending lengthwise through said body portion; vi. port means defined in said body portion sidewalls and isolated from said longitudinal downstream fluid passage means and extending through said sidewalls for communication with said body portion central bore.

Claim 16

A fluid delivery and transfer unit as disclosed in claim 12 additionally comprising: i. a tubular tool joint connector member secured to said body portion at the first end thereof and coaxial therewith, and having thread means on the distal end thereof for threaded interconnection with said inner pipe box joint member, and ii. a plurality of metal lugs radially spanning said annular downstream fluid passage and securing said outer pipe box joint member to said inner pipe box joint member.

Claim 17

A fluid delivery and transfer unit as disclosed in claim 12 additionally including resilient sealing means positioned on the interface between said tool joint connector member and said inner pipe box joint member.