Well bore force-measuring apparatus

Claim 2

Apparatus adapted for measuring downhole load conditions while drilling a borehole and comprising: a drill string having a borehole-drilling device dependently coupled to the lower end thereof and defining a fluid passage for circulating drilling fluids between the surface end of said drill string and said borehole-drilling device; a deformable load-responsive member having upper and lower portions respectively secured between longitudinally-spaced portions of said drill string and an unrestrained intermediate portion adapted to deform in response to increases and decreases in axial loads imposed on said drill bit tending to move said spaced drill string portions longitudinally in relation to one another and to tilt in relation to a normal upright position in response to torsional loads imposed on said drill bit tending to move said spaced drill string portions angularly in relation to one another; first transducer means coupled to said load-responsive member and having a measurable characteristic adapted to vary in response to deformation of said load-responsive member occurring upon relative longitudinal movement between said spaced drill string portions; torque-responsive means including second transducer means coupled to said load-responsive member and having a measurable characteristic adapted to vary in response to tilting movements of said load-responsive member away from its said normal position occurring upon relative angular movement between said spaced drill string portions; acoustic-signaling means on said drill string operatively coupled to said first and second transducer means and cooperatively arranged for producing acoustic signals in drilling fluids flowing through said drill string representative of variations in said measurable characteristics; and acoustic signal-detecting means operatively coupled to said surface end of said drill string and cooperatively arranged for detecting said acoustic signals.

Claim 3

The load-measuring apparatus of claim 1 wherein at least one of said measurable characteristics is an electrical property; and said first tranducer means include at least one strain gage mounted on said intermediate porion of said load-responsive member and exhibiting a varying range of said electrical property in response to strain variations occurring upon the deformation of said load-responsive member which are representative of the axial loads on said drill bit.

Claim 4

The load-measuring apparatus of claim 2 wherein said torque-responsive means include a deformable member projecting laterally from said intermediate portion of said load-responsive member and cooperatively arranged to deform in response to tilting movements of said load-responsive member, and said second transducer means include at least one strain gage mounted on said lateral member and exhibiting a varying range of said electrical property in response to strain variations occurring upon the deformation of said lateral member which are representative of the torsional loads on said drill bit.

Claim 5

The load-measuring apparatus of claim 1 wherein said load-responsive member is interior of said drill string; and further including: a sleeve member cooperatively arranged within said load-responsive meber and having upper and lower end portions respectively extending above and below said load-responsive member to said spaced portions of said drill string; first and second means respectively arranged between said upper and lower end portions of said sleeve member and said spaced portions of said drill string for defining an enclosed chamber around said load-responsive member; and pressure-regulating means cooperatively arranged on said drill string and adapted for maintaining said enclosed chamber at an elevated pressure about equal to the pressure of drilling fluids flowing through said drill string.

Claim 6

Apparatus adapted for measuring downhole load conditions while drilling a borehole and comprising: a multi-sectional drill string having a borehole-drilling device dependently coupled to the lower end thereof and defining a fluid passage for circulating drilling fluids between the surface end of said drill string and said borehole-drilling device; a tubular load-bearing body tandemly coupled between one of said drill string sections and said drill bit and having a longitudinal bore for conducting drilling fluids between said drill string sections and said drill bit; a load-responsive member having axially-spaced opposite portions respectively secured between longitudinally-spaced portions of said load-bearing body for normally maintaining said load-responsive member in an upright position and an unrestrained non-linear intermediate portion cooperatively arranged to deflect in response to axial loads imposed on said drill bit through said load-bearing body tending to move one of said spaced body portions longitudinally in relation to the other of said spaced body portions as well as to shift away from said upright position in response to torsional loads imposed on said drill bit through said load-bearing body tending to move one of said spaced body portions angularly in relation to the other of said spaced body portions; first means coupled to said intermediate portion of said load-responsive member and cooperatively arranged for providing a first output signal proportional to deflections of said intermediate portion of said load-responsive member occurring upon relative longitudinal movement between said spaced body portions caused by application of an axial load on said drill bit; second means coupled to said intermediate portion of said load-responsive member and cooperatively arranged for providing a second output signal proportional to the extent of movement of said load-responsive member away from its said upright position occurring upon relative angular movements between said spaced body portions caused by application of torque on said drill bit; intermediate proportional acoustic-signaling means on said drill string operatively coupled to said first and second means and cooperatively arranged for producing first and second acoustic signals in drilling fluids flowing through said drill string representative of said first and second output signals; acoustic signal-detecting means operatively coupled to said surface end of said drill string and cooperatively arranged for detecting said first and second acoustic signals to provide surface indications of axial and torsional loads imposed on said drill bit through said drill string.

Claim 7

Apparatus adapted for measuring downhole load conditions while drilling a borehole and comprising: a multi-sectional drill string having a borehole-drilling device dependently coupled to the lower end thereof and defining a fluid passage for circulating drilling fluids between the surface end of said drill string and said borehole-drilling device; a tubular load-bearing body tandemly coupled between one of said drill string sections and said drill bit and having a longitudinal bore for conducting drilling fluids between said drill string sections and said drill bit; a load-responsive member having axially-spaced opposite portions respectively secured between longitudinally-spaced portions of said load-bearing body for normally maintaining said load-responsive member in an upright position and an unrestrained non-linear intermediate portion cooperatively arranged to deflect in response to axial loads imposed on said drill bit through said load-bearing body tending to move one of said spaced body portions longitudinally in relation to the other of said spaced body portions as well as to shift away from said upright position in response to torsional loads imposed on said drill bit through said load-bearing body tending to move one of said spaced body portions angularly in relation to the other of said spaced body portions; first means coupled to said intermediate portion of said load-responsive member and cooperatively arranged for providing a first output signal proportional to deflections of said intermediate portion of said load-responsive member occurring upon relative longitudinal movement between said spaced body portions caused by application of an axial load on said drill bit; second means coupled to said intermediate portion of said load-responsive member and cooperatively arranged for providing a second output signal proportional to the extent of movement of said load-responsive member away from its said upright position occurring upon relative angular movements between said spaced body portions caused by application of torque on said drill bit; intermediate proportional acoustic-signaling means on said drill string operatively coupled to said first and second means and cooperatively arranged for producing first and second acoustic signals in drilling fluids flowing through said drill string representative of said first and second output signals; acoustic signal-detecting means operatively coupled to said surface end of said drill string and cooperatively arranged for detecting said first and second acoustic signals to provide surface indications of axial and torsional loads imposed on said drill bit through said drill string.

Claim 8

The load-measuring apparatus of claim 5 wherein said load-responsive member is interior of said load-bearing body.

Claim 9

The load-measuring apparatus of claim 6 further including: a sleeve member cooperatively arranged within said load-responsive member; first and second means respectively arranged between the upper and lower end portions of said sleeve member and said load-bearing body above and below said load-responsive member for defining an enclosed chamber therearound; and pressure-equalizing means on said load-bearing body and cooperatively arranged for maintaining said enclosed chamber at an elevated pressure at least about equal to the pressure of drilling fluids flowing through said longitudinal bore.

Claim 10

The load-sensing apparatus of claim 5 wherein said second means include a laterally-oriented deformable member secured between said load-bearing body and Said intermediate portion of said load-responsive member and cooperatively arranged to deform upon movement of said load-responsive member away from its said upright position, and transducer means including at least one strain gage cooperatively arranged on said deformable member and exhibiting a variable electrical characteristic which is proportional to the strain developed in said deformable member by deformation thereof upon application of torque to said drill bit.

Claim 11

The load-sensing apparatus of claim 5 wherein said intermediate portion of said load-responsive member is symmetrically curved away from an axis passing through said axially-spaced portions of said load-responsive member for producing a concentrated strain at about the mid-point of said intermediate portion upon deflection thereof; and said first means include at least one strain gage mounted on about said mid-point of said intermeidate portion and exhibiting a variable electrical characteristic which is proportortional to the strain developed in said mid-point of said intermediate portion n upon application of an axial load on said drill bit.

Claim 12

The load-sensing apparatus of claim 9 wherein said second means include a laterally-deformable member secured between said load-bearing body and said intermediate portion of said load-responsive member and cooperatively arranged to deform upon movement of said load-responsive member away from its said upright position, and transducer means including at least a second strain gage cooperatively arranged on said deformable member and exhibiting a variable electrical characteristic which is proportional to the strain developed in said deformable member by deformation thereof upon application of torque to said drill bit.

Claim 13

Apparatus adapted for measuring downhole load conditions while drilling a borehole and comprising: a multi-sectional drill string having a borehole-drilling device dependently coupled to the lower end thereof and defining a fluid passage for circulating drilling fluids between the surface end of said drill string and said borehole-drilling device; a tubular load-bearing body tandemly coupled between said drill bit and one of said drill string sections and having a longitudinal bore for conducting drilling fluids between said one drill string section and said drill bit; load-responsive means cooperatively arranged between upper and lower portions of said load-bearing body and adapted for selectively responding to compressional loads imposed on said drill bit through said load-bearing body tending to move said upper and lower body portions longitudinally in relation to one another and to torsional loads imposed on said drill bit through said load-bearing body tending to turn said upper and lower body portions angularly in relation to one another, said load-responsive means including a deformable loop coaxially arranged around an intermediate portion of said load-bearing body and divided into at least a first substantially-rounded compressible segment and at least a first elongated strip-like bendable segment having one end coupled to one side of said first rounded segment and extending laterally therefrom around said intermediate body portion, first and second means respectively securing the upper and lower edges of said first rounded segment to said upper and lower body portions for alternatively compressing said first rounded segment upon longitudinal movement of said upper and lower body portions toward one another and rolling said first rounded segment to an inclined position upon relative angular movement between said upper and lower body portions so as to correspondingly bend said first strip-like segment; first electrical transducer means cooperatively arranged on at least said first rounded segment and adapted for exhibiting a varying first electrical characteristic proportional to the magnitude of compressional forces applied to said first rounded segment upon application of an axial load through said load-bearinG body onto said drill bit; second electrical transducer means cooperatively arranged on at least said first strip-like segment and adapted for exhibiting a varying second electrical characteristic proportional to the magnitude of the turning forces applied to said first rounded segment upon application of a torsional load through said load-bearing body onto said drill bit; acoustic-signaling means on said drill string operatively coupled to said first and second transducer means and cooperatively arranged for producing first and second acoustic signals in drilling fluids flowing through said drill string respectively representative of the variations in said first and second electrical characteristics; and acoustic signal-detecting means operatively coupled to said surface end of said drill string and cooperatively arranged for detecting said first and second acoustic signals to provide surface indications of the axial and torsional loads imposed on said drill bit through said drill string.

Claim 14

Apparatus adapted for measuring downhole load conditions while drilling a borehole and comprising: a multi-sectional drill string having a borehole-drilling device dependently coupled to the lower end thereof and defining a fluid passage for circulating drilling fluids between the surface end of said drill string and said borehole-drilling device; a tubular load-bearing body tandemly coupled between said drill bit and one of said drill string sections and having a longitudinal bore for conducting drilling fluids between said one drill string section and said drill bit; load-responsive means cooperatively arranged between upper and lower portions of said load-bearing body and adapted for selectively responding to compressional loads imposed on said drill bit through said load-bearing body tending to move said upper and lower body portions longitudinally in relation to one another and to torsional loads imposed on said drill bit through said load-bearing body tending to turn said upper and lower body portions angularly in relation to one another, said load-responsive means including a deformable loop coaxially arranged around an intermediate portion of said load-bearing body and divided into at least a first substantially-rounded compressible segment and at least a first elongated strip-like bendable segment having one end coupled to one side of said first rounded segment and extending laterally therefrom around said intermediate body portion, first and second means respectively securing the upper and lower edges of said first rounded segment to said upper and lower body portions for alternatively compressing said first rounded segment upon longitudinal movement of said upper and lower body portions toward one another and rolling said first rounded segment to an inclined position upon relative angular movement between said upper and lower body portions so as to correspondingly bend said first strip-like segment; first electrical transducer means cooperatively arranged on at least said first rounded segment and adapted for exhibiting a varying first electrical characteristic proportional to the magnitude of compressional forces applied to said first rounded segment upon application of an axial load through said load-bearinG body onto said drill bit; second electrical transducer means cooperatively arranged on at least said first strip-like segment and adapted for exhibiting a varying second electrical characteristic proportional to the magnitude of the turning forces applied to said first rounded segment upon application of a torsional load through said load-bearing body onto said drill bit; acoustic-signaling means on said drill string operatively coupled to said first and second transducer means and cooperatively arranged for producing first and second acoustic signals in drilling fluids flowing through said drill string respectively representative of the variations in said first and second electrical characteristics; and acoustic signal-detecting means operatively coupled to said surface end of said drill string and cooperatively arranged for detecting said first and second acoustic signals to provide surface indications of the axial and torsional loads imposed on said drill bit through said drill string.

Claim 15

The load-measuring apparatus of claim 11 wherein said deformable loop is interior of said load-bearing body.

Claim 16

The load-measuring apparatus of claim 12 further including: a sleeve member cooperatively arranged within said deformable loop and having upper and lower end portions extending above and below said deformable loop; means cooperative with said upper and lower end portions of said sleeve member for defining an enclosed chamber around said deformable loop; and pressure-equalizing means on said load-bearing body and cooperatively arranged for maintaining said enclosed chamber at an elevated pressure at least about equal to the pressure of drilling fluids in said longitudinal bore.

Claim 17

The load-measuring apparatus of claim 11 wherein said first rounded segment is annular so that compressional forces imposed thereon will develop enhanced strains at selected positions thereon; and said first transducer means include at least one strain gage mounted on one of said selected positions and cooperatively arranged for responding to such enhanced strains.

Claim 18

The load-measuring apparatus of claim 11 wherein the other end of said first strip-like segment is secured against vertical movement so that torsional forces imposed on said first rounded segment tending to tilt said first strip-like segment will develop enhanced strains at selected positions thereon; and said second transducer means include at least one strain gage mounted on one of said selected positions and coooperatively arranged for responding to such enhanced strains.

Claim 19

The load-measuring apparatus of claim 11 wherein said deformable loop further includes a second substantially-rounded compressible segment circumferentially spaced from said first rounded segment and having one side coupled to the other end of said first strip-like segment, and a second elongated strip-like bendable segment coupled between the other sides of each of said first and second rounded segments.

Claim 20

The load-measuring apparatus of claim 16 wherein said first and second rounded segments are on opposite sides of said intermediate body portion.

Claim 21

The load-measuring apparatus of claim 16 wherein said first and second rounded segments are annular so that compressional forces imposed thereon will develop enhanced strains at selected positions on each of said rounded segments; and said first transducer means include a strain gage mounted on each of said selected positions and cooperatively arranged for responding to such enhanced strains upon application of axial loads through said load-bearing body onto said drill bit.

Claim 22

The load-measuring apparatus of claim 18 wherein said second transducer means include at least one strain gage mounted on each of said strip-like segments at a position thereon expected to experience maximum distortion and, therefore, enhanced strains upon application of torsional loads through said load-bearing body onto said drill bit.

Claim 23

The load-measuring appAratus of claim 11 wherein at least one of said first and second means respectively securing said upper and lower edges of said first rounded segment include a sleeve member defining a shoulder adapted to be securely engaged with one of said upper and lower edges, and sleeve-positioning means cooperatively arranged for securing said sleeve member to said load-bearing body in a selected position for securely engaging said sleeve shoulder with said one edge of said first rounded segment.