Neutron Generators for Measurements While Drilling

Abstract

The application discloses a neutron generator for measurement while drilling. The neutron generator comprises an upper connector, a spring damping mechanism, a neutron generator upper connector, a semiconductor refrigeration device, and a neutron tube arranged in sequence from top to bottom, the neutron generator also comprises a protection sleeve for containing the above parts, the semiconductor refrigeration device is arranged at the outside of an accelerating electrode of the neutron tube and used for cooling the accelerating electrode of the neutron tube, a cooling surface of the semiconductor refrigeration device is tightly contacted with a shell of the neutron tube, and the space between the heat radiation surface of the semiconductor refrigeration device and the protection sleeve is filled with heat conduction silicone grease. According to the neutron generator, during neutron porosity measurement while drilling based on the neutron generator, effective damping measures are taken, the neutron generator satisfies the requirement while drilling, the problem of unstable yield of neutrons due to overheating of the neutron tube is effectively solved via the control of the semiconductor refrigeration device, and the work time of the neutron generator is extended via the mode of time-sharing intermittent control of driving pulse.

Description

Technical field [0001] The present invention relates to the field of oil and natural gas drilling, in particular to a technology for measuring neutron porosity while drilling in a geosteering drilling system, and in particular to a technology for improving downhole reliability of a neutron generator in a neutron porosity measurement system while drilling Method and device. Background technique [0002] Neutron logging while drilling is a formation porosity measurement method. The neutron source carried by the measurement while drilling device emits high-energy fast neutrons to the surrounding formation, and the energy and intensity of the neutrons in the formation are measured in real time to obtain the formation. Porosity and other lithological parameters are mainly used for real-time formation evaluation during drilling. [0003] In the mid-1990s, several major foreign oilfield technical service companies (Schlumberger, Baker Hughes, Halliburton, Weatherford, etc.) have develope...

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Problems solved by technology

[0006] The purpose of the present invention is to overcome the deficiencies in the prior art, and provide a method and device for effectively improving the reliability of the neutron generator downhole, so as to solve the problem of neutron pores while drilling under the environment of high temperature, high pressure, and strong vibration and impact. Reliable and Stable Work of the Neutron Source of the Degree Measuring Instrument

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