Deuterium-deuterium controllable compensating neutron well logging instrument during drilling

Abstract

The invention provides a neutron-compensating-while-drilling logging device, for real-timely measuring stratum porosity around borehole in the well drilling course, where the side surface of a drill collar is made with a U-shaped groove, in which from the top down is equipped with receiver module compressive cylinder and generator module compressive cylinder, where they are equipped with receiver installation framework and generator installation framework, respectively, the receiver installation framework is equipped from the top down with signal processing circuit module, far neutron detector, far detector screening block, near neutron detector and near detector screening block inside, and the generator installation framework is equipped from the top down with generator control circuit, radiating device and neutron generator inside. And it adopts deuterium-deuterium reaction accelerator as neutron source, reducing radioactive damage to the human and environments and has longer service life and higher sensitivity, applied to geology- oriented well drilling.

Description

Technical field: [0001] The invention relates to a wireless measuring-while-drilling instrument used for geosteering in the petroleum drilling industry. Specifically, the present invention relates to a compensation neutron porosity logging tool for a neutron source of a deuterium-deuterium reaction accelerator while drilling. Background technique: [0002] In geosteering drilling in the petroleum industry, the neutron logging tool is used to measure the porosity of the formation around the wellbore in real time during the drilling process, so as to identify oil and gas layers and calculate the oil production capacity of the formation. Currently known LWD compensated neutron logging tools use a neutron source, and place two neutron detectors at different distances from the neutron source, and measure the ratio of the count rates of the two detectors, because the ratio mainly It reflects the hydrogen content of the formation, and hydrogen is usually contained in the fluid of ...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to provide a kind of compensated neutron logging tool while drilling, which is used to measure the porosity of the formation around the borehole in real time during the drilling process. Compared with the prior art, it overcomes the problem of using americium-beryllium neutron source The radioactive hazards to people and the environment, as well as the low lifetime and poor sensitivity of the deuterium-tritium reaction accelerator neutron source

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