Method of and apparatus for telemetering information from a point in a well borehole to the earth's surface

Abstract

Down-hole information from rotary well drilling operations is transmitted to a surface or remote location by the venting of drilling fluid from the interior of the drill stem into the bore hole annulus in a binary coded decimal format. A valve is caused to operate by the digital output of one or more down-hole transducers thus releasing and restoring the drilling fluid pressure in the desired sequence. A "sub" contains the necessary electronics, power supply and a motorized valve assembly. Commands from the surface to transmit information from any one of the transducers are transmitted by means of sequential pulses in a binary coded decimal format, in the drilling fluid pressure are provided by the operator by deliberately decreasing and then increasing the surface pump pressure in a sequence to which the applicable down-hole actuating means is responsive.

What we claim as our invention is: .[. 
     
       1.  A method of telemetering information from a point in a well bore-hole, to the earth's surface utilizing the drilling fluid pump pressure comprising the steps of detecting the information required, translating and transmitting said information into digital signals, decreasing and then increasing the pump pressure by venting the drilling fluid in a binary coded decimal format, by said digital signals, remotely detecting said decreases and increases of drilling fluid pump pressure and then decoding and displaying the results of said increases and decreases of said drilling fluid pump pressure and hence the information detected, said translation and transmitting of the information being initiated by the additional step of first decreasing and then increasing the drilling fluid pump pressure at the surface in a predetermined sequence..]. .[.2. In a well drilling rig which includes a hollow drill string assembly within a bore-hole thereby defining a bore-hole annulus, a rotatable bit on the lower end of said hollow drill string, drill fluid restrictive nozzles in said bit, a drilling fluid circulation system including a pump and a source of drilling fluid, and conduit means operatively connecting said pump to said source of drilling fluid and to said hollow drill string; the improvement comprising in combination a down-hole assembly installed within the associated drill string, means to convey the associated drilling fluid under pressure, through said assembly, a motorized valve within said assembly operatively connected between said means to convey associated drilling fluid through said assembly and the associated bore-hole annulus when the valve is open and to shut off said last mentioned means when said valve is closed, at least one information responsive transducer operatively connected to said assembly, electronic means in said assembly to translate information received by said transducer, into means to open and close said valve in a binary coded decimal sequence thereby decreasing and increasing the drilling fluid pressure in said predetermined sequence, means remote from said assembly to detect said decreases and increases in drilling fluid pressure and means to decode and display said detected decreases and increases in drilling fluid pressure, and a source of electrical power for said assembly..]. .[.3. The assembly according to claim 2 which includes a rate of pressure change switch operatively connected to said motorized valve whereby said valve only operates responsive to a decrease and increase in pressure if the pressure of the drilling fluid changes a predetermined amount in a fixed time or period..]. .[.4. The assembly according to claim 2 in which the assembly includes a cylindrical casing, a drilling fluid conduit extending through said casing, an annular cavity defined between said conduit and said casing, said conduit being offset through part of said casing, said casing including an electronic holding section within said cavity, an electro-mechanical holding section within said cavity adjacent said offset, and a power supply holding section within said cavity, and means to seal off said cavities one from the other, said casing being adjacently connected within said drill string..]. .[.5. The assembly according to claim 2 in which said electronic means in said assembly translates information received by said transducer into digital signals for opening and closing said valve..]. .[.6. The assembly according to claim 5 which includes remote input means operatively connected to said drilling fluid circulation system to decrease and then increase the associated pump pressure in a sequence to which said means to open and close said valve is responsive thereby initiating the operation of said valve to signal information received from said transducer within said assembly, to said means to decode and display said detected decreases 
     
     
        and increases in said drilling fluid pump pressure..]. .[.7.  The assembly according to claim 5 in which the assembly includes a cylindrical casing, a drilling fluid conduit extending through said casing, an annular cavity defined between said conduit and said casing, said conduit being offset through part of said casing, said casing including an electronic holding section within said cavity, an electromechanical holding section within said cavity adjacent said offset, and a power supply holding section within said cavity, and means to seal off said cavities one from the other, said casing being adjacently connected within said drill string..]. .[.8. The assembly according to claim 3 in which the assembly includes a cylindrical casing, a drilling fluid conduit extending through said casing, an annular cavity defined between said conduit and said casing, said conduit being offset through part of said casing, said casing including an electronic holding section within said cavity, an electromechanical holding section within said cavity adjacent said offset, and a power supply holding section within said cavity and means to seal off said cavities one from the other, said casing being adjacently connected within said drll string..]. .[.9. The assembly according to claim 5 which includes said means remote from said assembly comprising a pressure-to-voltage transducer operatively connected to said conduit means between said pump and said hollow drill string, electronic means to receive and decode signals from said pressure-to-voltage transducer, operatively connected to said transducer and readout means operatively connected to said electronic means..]. .[.10. The assembly according to claim 9 which includes remote input means operatively connected to said drilling fluid circulation system to decrease and then increase the associated pump pressure in a sequence to which said means to open and close said valve is responsive thereby initiating the operation of said valve to signal information received from said transducer within said assembly, to said means to decode and display said detected decreases and increases in said drilling fluid pump pressure..]. .[.11. The assembly according to claim 2 which includes said means remote from said assembly comprising a pressure-to-voltage transducer operatively connected to said conduit means between said pump and said hollow drill string, electronic means to receive and decode signals from said pressure-to-voltage transducer, operatively connected to said transducer and read-out means operatively connected to said electronic means..]. .[.12. The assembly according to claim 11 which includes remote input means operatively connected to said drilling fluid circulation system to decrease and then increase the associated pump pressure in a sequence to which said means to open and close said valve is responsive thereby initiating the operation of said valve to signal information received from said transducer within said assembly, to said means to decode and display said detected decreases and increases in said drilling fluid pump pressure..]. .[.13. The assembly according to claim 2 which includes remote input means operatively connected to said drilling fluid circulation system to decrease and then increase the associated pump pressure in a sequence to which said means to open and close said valve is responsive thereby initiating the operation of said valve to signal information received from said transducer within said assembly, to said means to decode and display said detected decreases and increases in said drilling fluid pump pressure..]. .[.14. The assembly according to claim 13 in which the assembly includes a cylindrical casing, a drilling fluid conduit extending through said casing, an annular cavity defined between said conduit and said casing, said conduit being offset through part of said casing, said casing including an electronic holding section within said cavity, an electro-mechanical holding section within said cavity adjacent said offset, and a power supply holding section within said cavity, and means to seal off said cavities one from the other, said casing being adjacently connected within said drill string..]. 
     
     
        .[.15.  An information and transmitting assembly for rotary oil well drilling string comprising in combination a cylindrical casing, a drilling fluid conduit extending through said casing, an annular cavity defined between said conduit and said casing, said conduit being offset through part of said casing, a down-hole assembly installed within said casing, a motorized valve within said casing adjacent said offset, said valve being operatively connected between said conduit and the exterior of said casing when said valve is open and shutting off the connection between said conduit and the exterior of said casing, when said valve is closed, at least one information responsive transducer within said casing, electronic means in said casing to translate information received by said transducer into means to open and close said valve in a binary coded decimal system thereby decreasing and increasing the drilling fluid pressure within said conduit, means remote from said casing to detect decreases and increases in drilling fluid pressure and means to decode and display said detected decreases and increases in drilling fluid pressures and a source of electrical power within said casing..]. .[.16. The assembly according to claim 15 which includes remote input means operatively connected to said drilling fluid circulation system to decrease and then increase the associated pump pressure in a sequence to which said means to open and close said valve is responsive thereby initiating the operation of said valve to signal information received from said transducer within said assembly, to said means to decode and display said detected decreases and increases in said drilling fluid pump pressure..]. .[.17. The assembly according to claim 15 which includes a rate of pressure change switch operatively connected to said motorized valve whereby said valve only operates responsive to a decrease and increase in pressure if the pressure of the drilling fluid changes a predetermined amount in a fixed time or period..]. .[.18. The assembly according to claim 15 in which the assembly includes a cylindrical casing, a drilling fluid conduit extending through said casing, an annular cavity defined between said conduit and said casing, said conduit being offset through part of said casing, said casing including an electronic holding section within said cavity, an electromechanical holding section within said cavity adjacent said offset, and a power supply holding section within said cavity, and means to seal off said cavities one from the other, said casing being adjacently connected within said drill string..]. .[.19. The assembly according to claim 15 in which said electronic means in said assembly translates information received by said transducer, into digital signals for opening 
     
     
        and closing said valve..]. .[.20.  The assembly according to claim 19 which includes remote input means operatively connected to said drilling fluid circulation system to decreae and then increase the associated pump pressure in a sequence to which said means to open and close said valve is responsive thereby initiating the operation of said valve to signal information received from said transducer within said assembly, to said means to decode and display said detected decreaes and increases in said drilling fluid pump pressure..]. .[.21. The assembly according to claim 19 which includes said means remote from said assembly comprising a pressure-to-voltage transducer operatively connected to said conduit means between said pump and said hollow drill string, electronic means to receive and decode signals from said pressure-to-voltage transducer, operatively connected to said transducer and read-out means operatively connected to said electronic means..]. .[.22. The assembly according to claim 21 which includes remote input means operatively connected to said drilling fluid circulation system to decrease and then increase the associated pump pressure in a sequence to which said means to open and close said valve is responsive thereby initiating the operation of said valve to signal information received from said transducer within said assembly, to said means to decode and display said detected decreases and increases in said drilling fluid pump pressure..]. .[.23. The assembly according to claim 15 which includes said means remote from said assembly comprising a pressure-to-voltage transducer operatively connected to said conduit means between said pump and said hollow drill string, electronic means to receive and decode signals from said pressure-to-voltage transducer, operatively connected to said transducer and read-out means operatively connected to said electronic means..]. .[.24. The assembly according to claim 23 which includes remote input means operatively connected to said drilling fluid circulation system to decrease and then increase the associated pump pressure in a sequence to which said means to open and close said valve is responsive thereby initiating the operation of said valve to signal information received from said transducer within said assembly, to said means to decode and display said detected decreases 
     
     
        and increases in said drilling fluid pump pressure..]. .Iadd.25.  A method of telemetering information from a point in a well borehole to the earth'surface by utilizing a drill string extending into the borehole, and thereby defining a borehole annulus, a drill bit on one end of the drill string having at least one restrictive nozzle therein, a drilling fluid pump connected to the other end of the drill string, an assembly connected in the drill string and having an unobstructed passage therethrough, a bypass passageway in the assembly directly communicating the unobstructed passage to the borehole annulus and a motorized valve in said bypass passageway, the method comprising the steps of continuously pumping drilling fluid under pressure through the drill string, through the unobstructed flow passage and out through the drill bit nozzle, detecting at a point in the borehole the information to be telemetered, translating and transmitting said information into digital signals, using said digital signals in operating said valve to plurally decrease and increase the fluid pressure in the drilling string by plurally opening and closing the valve in the bypass passageway in a coded decimal format thereby venting a portion of the drilling fluid directly into the borehole annulus and bypassing the drill bit nozzle with said portion of fluid while maintaining continuous unobstructed drilling fluid flow through the assembly and continuous flow through the drill bit nozzle, detecting the decreases and increases in the drilling fluid pressure while continuously circulating the drilling fluid and decoding and displaying at the surface the results of the decreases and increases in drilling fluid pump pressure. .Iaddend. .Iadd.26. In a well drilling system which includes a hollow drill string within a borehole thereby defining a borehole annulus, a drill bit on one end of said hollow drill string, at least one drilling fluid restrictive nozzle in said bit, a drilling fluid circulation system including a surface pump and a source of drilling fluid, and conduit means operatively connecting said pump to said source of drilling fluid and to the other end of said hollow drill string; the improvement comprising in combination, a down-hole assembly having means connecting the assembly in the drill string, a continuous unobstructed passage through said assembly in communication with said drill string, a bypass passageway in said assembly directly communicating the unobstructed passage in the assembly to the borehole annulus and bypassing said drill bit nozzle, a motorized valve in the bypass passageway for controlling fluid flow directly to the associated borehole annulus when the valve is open and to shut off said last mentioned flow when said valve is closed, at least one information responsive transducer operatively connected to said assembly, means in said assembly to translate information received by said transducer into means to plurally open and close said valve in a coded decimal sequence thereby plurally decreasing and increasing the drilling fluid pressure in said sequence, means remote from said assembly to detect said decreases and increases in drilling fluid pressure, means operatively connected to said detecting means to decode said detected decreases and increases in drilling fluid pressure and means at the surface to display the decoded information. .Iaddend.