WELL REAMER Russian patent published in 2004 - IPC

FIELD: drilling equipment, particularly for increasing well size in predetermined range.

SUBSTANCE: reamer body has radial orifices and central through passage with spring-loaded shaft installed inside passage. Orifices are formed in upper and lower shaft parts. Orifices of upper shaft part are closed when reamer tools are in working position. Inclined slots for legs with axles fixation are formed on outer body surface. Axles are installed in supports to which roller cutters are secured. Supports are rigidly connected to cylindrical pistons arranged in bores of inclined body. Bores communicating with central through pass are sealed off from ambient air. Rammer has pistons connected with shaft by sliders, which may perform radial movement relative shaft and vertical movement along body slots.

EFFECT: increased reamer working capacity and reliability.

3 dwg