The invention belongs to the field of applied geophysical exploration / acoustic
logging, and particularly relates to an acoustic
logging-while-drilling device of a variable-
diameter sound insulation structure. The acoustic
logging-while-drilling device of the variable-
diameter sound insulation structure comprises
drill collars, a
sound wave transmitting device and a
sound wave receiving device are arranged outside the
drill collars, and the acoustic logging-while-drilling device is characterized in that a variable-
diameter sound insulator is arranged between the
sound wave transmitting device and the sound wave receiving device, and the
drill collars comprise a drill collar with a first inner diameter and a first length, a drill collar with a second inner diameter and a second length, a drill collar with a third inner diameter and a third length and a drill collar with a fourth inner diameter and a fourth length from the transmitting device to the receiving device. The acoustic logging-while-drilling device lowers
processing difficulty and cost, and meanwhile enhances the
mechanical strength of the drill collars.
Energy transfer between an
energy converter and the drill collars is structurally obstructed, and the variable-diameter sound insulator is combined to further eliminate the interference of the drill collars to stratum signals.