Abstract: Featured is a gearbox used to interconnect an electric motor to a deep oil well tube pump. The gearbox includes a drive shaft interconnected to the pump, a reduction gear assembly interconnected to the drive shaft and the electric motor, a bearing system that axially and radially supports rotating members of the reduction gear assembly, a lubrication system and a compensator that is fluidly coupled to the lubrication system. The compensator provides pressure compensation between the pressure external to the gearbox and the internal pressure of the lubrication system. The reduction gear assembly includes one or more stages of planetary gearing, wherein a final planet stage includes three or more planet wheels, a pinion cage and a pinion cage member. The bearing system includes a bearing sub-assembly for supporting the final planet stage, the bearing sub-assembly including a plurality of axial and radial bearings.

Abstract: Featured is a gearbox that is used to interconnect an electric motor to a deep oil well tube pump such as an eccentric worm pump. The gearbox includes a drive shaft mechanically interconnected to the pump, a reduction gear assembly mechanically interconnected to the drive shaft and the electric motor, a bearing system that axially and radially supports rotating members of the reduction gear assembly, a lubrication system and a compensator that is fluidly coupled to the lubrication system. The lubrication system provides a lubricating fluid to the bearing system and the gear reduction assembly for lubrication and cooling. The compensator includes a reservoir of cooled lubricating fluid for the lubrication system and also provides pressure compensation between the pressure external to the gearbox and the lubrication system and the internal pressure of the lubrication system.