Claims
- 1. An apparatus for detecting pressure pulses communicated through drilling fluid contained in a conduit comprising:
- an access port formed in the conduit;
- a pressure transducer for determining the pressure at an input port to said transducer and converting said pressure to an electrical signal; and
- a waveguide disposed between said access port in the conduit and said input port in said transducer, said wave guide operable to increase the amplitude of an acoustic signal transmitted therethrough.
- 2. The apparatus of claim 1 wherein said waveguide contains drilling fluid for transmitting the pressure pulses to said transducer.
- 3. The apparatus of claim 1 wherein said waveguide contains a second fluid for transmitting the pressure pulses to said transducer wherein said second fluid has a viscosity greater than the viscosity of the drilling fluid.
- 4. The apparatus of claim 3 further comprising a membrane disposed in said waveguide for retaining said second fluid in said waveguide and preventing the drilling fluid from becoming mixed with said second fluid.
- 5. The apparatus of claim 1 wherein said waveguide comprises a hose.
- 6. The apparatus of claim 5 wherein said hose is contained in an enclosure.
- 7. The apparatus of claim 5 wherein the pressure pulses are transmitted through the drilling fluid with a predetermined wave length, and wherein said hose has a length equal to at least one quarter of said wavelength of the pressure pulses.
- 8. The apparatus of claim 5 wherein said hose has a length greater than thirty five feet.
- 9. The apparatus of claim 1 wherein said waveguide includes a first segment having a first inside diameter and a second segment having a second inside diameter, wherein said second inside diameter is less than said first inside diameter.
- 10. The apparatus of claim 9 wherein the pressure pulses are transmitted through the drilling fluid with a predetermined wave length, and wherein said second segment of said waveguide has a length equal to at least one quarter of said wavelength.
- 11. The apparatus of claim 9 wherein said first and second segments of said waveguide comprise sections of hose interconnected by a hose connector.
- 12. The apparatus of claim 9 wherein said waveguide contains a second fluid for transmitting the pressure pulses to said transducer wherein said second fluid has a viscosity greater than the viscosity of the drilling fluid.
- 13. An apparatus for detecting an acoustic signal of wavelength W and frequency F in drilling mud contained in a conduit comprising:
- a pressure port formed in the conduit;
- a pressure transducer;
- a hose having a first end connected to said pressure port and having a second end connected to said pressure transducer, wherein said hose has a length sufficient for said hose to function as a waveguide for the acoustic signal which increases the amplitude of said acoustic signal; and
- a fluid substantially filling said hose.
- 14. The apparatus of claim 13 wherein said fluid has a viscosity greater than the viscosity of the drilling mud.
- 15. The apparatus of claim 14 further comprising means for retaining said fluid in said hose and maintaining a separation between said fluid and the drilling mud.
- 16. The apparatus of claim 13 wherein said hose includes resilient wall surfaces, said resilient wall surfaces dampening signals having a frequency greater than F at a rate faster than said surfaces dampen the acoustic signal.
- 17. The apparatus of claim 13 wherein said hose includes a first segment having a first inside diameter and a second segment having a second inside diameter, wherein said second inside diameter is less than said first inside diameter.
- 18. The apparatus of claim 17 wherein said second segment of said hose has a length at least as long as one quarter W.
- 19. The apparatus of claim 17 wherein said second segment of said hose has an inside diameter that is approximately one half as large as said inside diameter of said first segment.
- 20. The apparatus of claim 13 wherein said fluid comprises drilling mud.
- 21. The apparatus of claim 13 wherein said fluid comprises glycerine.
- 22. The apparatus of claim 13 wherein said hose is contained in an enclosure.
- 23. An apparatus for detecting an acoustic signal of wavelength W and frequency F in drilling fluid comprising:
- a pipe containing the drilling fluid;
- an access port in said pipe;
- a T-connector connected to said access port, said T-connector including a first and a second output end;
- a differential pressure transducer having a first and a second input port;
- a waveguide connected between said first output end of said T-connector and said first input port of said pressure transducer, said wave guide being operable to increase the amplitude of an acoustic signal transmitted therethrough; and
- a conduit connected between said second output end of said T-connector and said second input port of said pressure transducer.
- 24. The apparatus of claim 23 wherein said waveguide comprises a hose.
- 25. The apparatus of claim 24 wherein said waveguide contains a second fluid having a viscosity greater than the viscosity of the drilling fluid.
- 26. The apparatus of claim 25 further comprising a diaphragm disposed in said waveguide, said diaphragm separating said second fluid and the drilling fluid.
- 27. The apparatus of claim 23 wherein said waveguide comprises a first segment having a first inside diameter and a second segment having a second inside diameter, wherein said second inside diameter is less than said first inside diameter.
- 28. The apparatus of claim 27 wherein said second segment comprises a hose.
- 29. The apparatus of claim 28 wherein said second segment has a length of at least 1/4 W.
- 30. The apparatus of claim 29 wherein said second segment contains a second fluid having a viscosity greater than the viscosity of the drilling fluid.
- 31. The apparatus of claim 23 wherein said conduit has a length less than that length required to function as a waveguide.
- 32. The apparatus of claim 23 wherein said conduit comprises a hose.
- 33. A method for detecting an acoustic signal of wavelength W and frequency F in drilling fluid flowing in a supply line comprising the steps of:
- providing an access port in the supply line;
- providing a pressure transducer for sensing the acoustic signal and converting the acoustic signal into electrical signals;
- connecting a waveguide between said pressure transducer and said access port, said wave guide operable to increase the amplitude of an acoustic signal transmitted therethrough; and
- substantially filling said waveguide with a medium capable of conducting acoustic signals.
- 34. The method of claim 33 further comprising substantially filling said waveguide with a fluid having a viscosity greater than the viscosity of the drilling fluid.
- 35. The method of claim 34 further comprising providing a membrane in said waveguide for maintaining separation between said fluid and the drilling fluid.
Parent Case Info
This is a continuation of application Ser. No. 08/292,090 filed on Aug. 17, 1994, now U.S. Pat. No. 5,459,697.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
5283768 |
Rorden |
Feb 1994 |
|
5459697 |
Chin et al. |
Oct 1995 |
|
Continuations (1)
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Number |
Date |
Country |
Parent |
292090 |
Aug 1994 |
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