A. Develop independently a new type of mounted mud pulser for MWD and apply ;
B. Simple structure, convenient operation and easy for maintenance; available for connection to near bit instrument;
C. Long service life and 100 hours of stable operation;
D. High temperature resistance of 175℃ and high pressure resistance of 150 Mpa;
E. Suitable for the environment: Displacement: 12～55 L/s（4-1/8~17”borehole）
F. Specification of 4.75”and 6.75”.