SUBMERSIBLE AIR HAMMER Russian patent published in 2011 - IPC E21B4/14 

FIELD: construction.

SUBSTANCE: submersible air hammer comprises a body with an axle box arranged in its upper part and forming a circular exhaust chamber with the body, a stepped hammer with a through central cavity, forming forward and return chambers with the body, a distribution stem having discharge and exhaust channels, and a drill bit with the central exhaust channel. Between the upper stage of the hammer and the body, below the axle box, there is an intermediate exhaust chamber, and in the lower part of the axle-box there are external longitudinal slots, via which the intermediate and circular exhaust chambers are communicated to each other and to the exhaust channel of the distribution stem.

EFFECT: increased efficiency of operation due to increased impact strength of the machine and its resource by prevention of sludge material suction from hole annulus into a return flow chamber.

2 dwg