BOREHOLE TRACTOR Russian patent published in 2014 - IPC E21B23/14 E21B4/04 

FIELD: transport.

SUBSTANCE: tractor consists of cylindrical body, motor connected with pump, hinged wedging supports with wheels and activator. Pump is connected with first and second fine filters connected with safety valve and, jointly with pressure gage, with check valve connected via first pressure control valve with wedging support activator. First, second, third and fourth hydraulic motors are fitted in every wheel. Note here that first, second and third flow splitters are connected via second pressure control valve to every hydraulic motor. Every said splitter is connected with second, third, fourth and fifth pressure gages connected with ADC and processor. This hydraulic system incorporates tank with equalising valve. Note here that said tank is connected with first, second and third fine filters. Note also that first pressure gage is connected with second pressure control valve. Third fine filter is connected to check valve, first and pressure control valves and every hydraulic motor.

EFFECT: higher efficiency.

2 dwg