Abstract: A reaming device connects to downhole motor with paralleled driving structure. The downhole motor contains power section assembly, sleeve and connection pad. The power section assembly has a rotor and a stator in which the stator covers the rotor. The sleeve is located inside the rotor that drives the sleeve to make rotation. The connection pad is affixed to and rotates with the sleeve is disposed on the one end of the extended part of rotor from the bottom of sleeve. The reamer is set on the stator of power section assembly or on the cover connecting to the stator from power section assembly. The rotor drives the reamer to rotate with the stator or on the cover connecting to the stator through the sleeve and the connection pad.
Abstract: A system of near-bit measurement while drilling system includes motor system, measurement transmission system, wireless receiving system and non-magnetic short sub. The measurement transmission system is set inside the motor system, and the transmitting device from the measurement transmission system and the receiving device from the wireless receiving system are set inside the non-magnetic cavity. In the process of drilling via drill bit, the azimuth gamma and the well deviation parameters on the formation where the drill bit is located is able to be measured in real time more accurately and then will make real-time wireless transmission toward the wireless receiving system. Compared with conventional measurement while drilling work, the measurement location of the near-bit measurement while drilling system is nearer to the drill bit with non-hysteretic description of well trajectory and formation gamma measurement so as to enhance the drilling-encounter ratio significantly.