Nuclear detectors built directly into shielding or modulating material
An apparatus for measuring radiation in a borehole penetrating the Earth, the apparatus includes: a downhole tool having a structure defining a cavity; and one or more radiation detection components integrated into the cavity and configured to measure the radiation. An apparatus conveyable through a borehole for measuring radiation downhole and a method of producing a downhole apparatus for measuring radiation are provided.
1. An apparatus for measuring radiation in a borehole penetrating the Earth, the apparatus comprising:
a downhole tool;
shielding disposed in the downhole tool and comprising a structure defining a cavity; and
a plurality of radiation detection components integrated into the cavity and configured to measure the radiation;
wherein:
the shielding is configured to shield each of two longitudinal ends of the cavity;
the shielding forms a contoured cradle for carrying each radiation detection component in the plurality of radiation detection components;
the shielding completely shields at least one radiation detection component in the plurality of radiation detection components radially about a longitudinal axis; and
the shielding forms a housing for the plurality of radiation detection components.
2. The apparatus as in claim 1 , wherein the shielding material comprises at least one of lead, tungsten, boron, a hydrogenous material, and a composite thereof.
3. The apparatus as in claim 1 , wherein the shielding material comprises a window configured to admit the radiation.
4. The apparatus as in claim 1 , wherein the plurality of radiation detection components include a gas-filled detector and a preamplifier.
5. The apparatus as in claim 4 , wherein a fill gas for the gas-filled detector comprises at least one of helium-3, xenon, argon, methane and a mixture of gases.
6. The apparatus as in claim 1 , wherein the plurality of radiation detection components include a scintillator and a photomultiplier tube.
7. The apparatus as in claim 6 , wherein the scintillator comprises at least one of NaI, NaI(Tl), Li-6, BGO, LaHa, CsI(Tl), CsI(Na), CsI(pure), CsF, KI(Tl), LiI(Eu), BaF 2 , CaF 2 (Eu), ZnS(Ag), CaWO 4 , CdWO 4 , YAG(Ce) Y 3 Al 5 O 12 (Ce), GSO, LSO, LaCl3(Ce) and LaBr3(Ce).
8. The apparatus as in claim 1 , wherein the structure is electrically insulated from a remaining portion of the downhole tool.
9. The apparatus as in claim 1 , further comprising an interface to an electronics unit.
10. The apparatus as in claim 1 , wherein a suspension structure is disposed directly between the cavity formed by the shielding and the plurality of radiation detection components.
11. The apparatus as in claim 1 , wherein the cavity forms a pressure boundary for a fill gas configured to provide an electrical signal upon interacting with the radiation.
12. An apparatus for measuring radiation in a borehole penetrating the Earth, the apparatus comprising:
a carrier configured to be conveyed through the borehole;
a downhole tool coupled to the carrier;
shielding disposed in the downhole tool and comprising a structure defining a cavity; and
a plurality of radiation detection components integrated into the cavity and configured to measure the radiation;
wherein:
the shielding is configured to shield each of two longitudinal ends of the cavity;
the shielding forms a contoured cradle for carrying each radiation detection component in the plurality of radiation detection components;
the shielding completely shields at least one radiation detection component in the plurality of radiation detection components radially about a longitudinal axis; and
the shielding forms a housing for the plurality of radiation detection components.
13. The apparatus as in claim 12 , further comprising an electronics unit for operating one or more of the radiation detection components in the plurality of radiation detection components.
14. The apparatus as in claim 12 , further comprising an electronics unit for analyzing a signal from one or more of the radiation detection components in the plurality of radiation detection components.
15. The apparatus as in claim 12 , further comprising at least one of a pre-amplifier, an amplifier, a battery, a transformer, a rectifier, an inverter, a single channel analyzer, a multi-channel analyzer, memory, storage, a processor, an interface and a communications link for supporting one or more radiation detection components in the plurality of radiation detection components.
16. The apparatus of claim 12 , wherein the carrier comprises at least one of a wireline, a slickline, a drill string, and coiled tubing.
17. A method for producing an apparatus for measuring radiation in a borehole penetrating the Earth, the method comprising:
selecting a downhole tool comprising shielding having a structure defining a cavity therein and being configured to shield each of two longitudinal ends of the cavity; and
integrating one or more radiation detection components into the cavity;
wherein:
the shielding is configured to shield each of two longitudinal ends of the cavity;
the shielding forms a contoured cradle for carrying each radiation detection component in the plurality of radiation detection components;
the shielding completely shields at least one radiation detection component in the plurality of radiation detection components radially about a longitudinal axis; and
the shielding forms a housing for the plurality of radiation detection components.