Design Of Acoustic Logging-while-drilling Tool

This paper is based on the monopole acoustic logging system and starts from the electrical part of the logging while drilling.The characteristics and functions of the logging-while-drilling tool and requirements of engineering practice are considered as factors of this design.The features of the present high performance processor such as signal processing ability,fast operation,low power consumption,multi module integrated are used in this design.Base on these characteristics,functions of the signal generation and acquisition,data processing and storage are designed in a circuit system,which is used for the acoustic logging-while-drilling tool.The principle of acoustic logging and the working principle of logging-while-drilling tool are discussed in this paper.The performance index of the instrument design has been proposed,which is based on the characteristics and working requirements of logging-while-drilling tool.The best design is selected as the system's overall design scheme.During the design process,first of all,in accordance with the function of the instrument,the instrument is split into several modules,next,the modules are designed,in addition,according to the working condition of the logging-while-drilling tool,the best preference method of extracting the slowness is selected.In this design,the advanced integrated processor is used in signal sampling,storage,transmission and other functions.By multiplexing samples and SPI technologies,high-speed data storage is implemented.The complexity of the system is reduced.Characterized by low density,multi-modular design is abandoned.Using this design,circuit board area is reduced,the smaller circuits is more suitable for the working environment of logging-while-drilling tool.In the end of the paper testing the various functions proves the rationality and practicality of the design.