The System Design For Natural Gamma LWD Tools

With the development of world economy and industry, the demand to oil and gas resource increase greatly in all countries, because of non-renewal of oil and gas resources, it become the goal to enhance the recovery of oil and gas. With the technical blockade of the foreign company and huge demand of domestic application market, the research and development of natural gamma LWD tools has important Significance to enhance research and development level of our country's oil logging tools, to break the technical monopoly of foreign high-end equipment, to reduce drilling cost, and to increase oil production.This paper systematically describes the basic concepts, the theoretical foundation, the latest progress of oil logging and so on, and has in-depth analysis about the research significance of natural gamma LWD tools, the principles and calibration of radioactive logging methods. On this base it has detail description of natural gamma LWD tools, and analyzes the system hardware and software design methods, including the overall analysis and design, power circuit design, pulse shaping circuit design, GR data acquisition and storage circuit design and so on. In view of long hours working at high temperature, high pressure, high vibration environment, it propose new design method of reliability design for natural gamma LWD tools to meet the demand of field application. Finally, testing of part of the instrument and field application proven the property and indicate of the instrument.