NOISE DAMPING PROTECTIVE DEVICE OF ROCK DRILLING UNIT Russian patent published in 2011 - IPC E21B7/02 

FIELD: oil and gas production.

SUBSTANCE: device consists of feeding girder, one end of which corresponds to drill end, of case for sound absorbing, enveloping feeding girder, perforator and part of drill rod, of first protective part, stationary arranged on drill end of feeding girder, as end of case for sound damping, and of second protective part travelling in lengthwise direction relative to feeding girder. Protective parts have an orifice; the drill rod travels in this orifice during drilling; also, the drill rod is connected to perforator moving during drill operation on the feeding girder. The device is equipped with a tubular protective part, flexible at least in its lengthwise direction and positioned between orifices of the first and second protective parts; with its ends it is tightly attached to the first and second protective parts so, that it forms a closed space between the orifices of the first and second protective parts. Also, the device is equipped with a guide in lengthwise direction of the feeding girder. The second protective parts is connected to the guide and travels relative to it. There is a cylinder with a medium, operating under pressure between the first and the second protective parts to move protective part to the first protective part and away from it.

EFFECT: raised efficiency at sound damping.

9 cl, 3 dwg