Water lubricated line shaft bearing and lubrication system for a geothermal pump

摘要

The present invention provides a water lubricated line shaft bearing assembly,comprising an outer annular steel shell and an inner layer made of low frictionmaterial attached to the outer shell, the inner layer having a non-uniform thicknesswhich is formed with wall portions of increased thickness defining a pluralityof shaft engaging portions and with wall portions of reduced thickness defininga plurality of lubricant passages. The shaft engaging portions are capable ofbeing journalled on a line shaft adapted to drive a downhole geothermal productionpump and the steel shell is engageable with an inner wall of a lubrication tubevertically extending through a water column through which pumped geothermalfluid is delivered, lubrication water bled from the pumped geothermal fluidbeing used to supply lubrication water through the lubricant passages. The steelshell has sufficient compressive strength to withstand the stress imposed bythe high rotational speed of the line shaft of the geothermal production pump.The low friction material of the inner liner allows solid debris present or entrainedin the lubrication water to slide over the inner line. Solid debris is preventedfrom accumulating due to the presence of the passages through which the lubricationwater flows.