Self lubricating submersible pumping system

Abstract

A lubrication technique for one or more components used in the production of subterranean fluids. The technique comprises the separation of particulates from a produced fluid having lubricating ability. Following separation of the particulate matter, the lubricating fluid is directed to specific areas, such as bearing surfaces within a submersible pump, to facilitate continued operation of the overall system.

What is claimed is:  
     
         1 . A lubrication system, comprising: 
 an electric submersible pumping system having a submersible pump and a particulate separator disposed downstream of the submersible pump, the submersible pump comprising a shaft with an internal lubrication flow path positioned to receive a fluid from the particulate separator subsequent to separation of particulates:from the fluid.    
     
     
         2 . The lubrication system as recited in  claim 1 , wherein the submersible pump comprises a plurality of bearing regions, and the internal lubrication flow path extends to the plurality of bearing regions.  
     
     
         3 . The lubrication system as recited in  claim 1 , wherein the particulate separator comprises a centrifugal sand separator.  
     
     
         4 . The lubrication system as recited in  claim 1 , wherein the electric submersible pumping system comprises an electric motor to drive the submersible pump and the particulate separator.,  
     
     
         5 . The lubrication system as recited in  claim 1 , wherein the internal lubrication flow path comprises an axial passage disposed along an axis of the shaft and a plurality of transverse passages extending from the axial passage to the exterior of the shaft.  
     
     
         6 . The lubrication system as recited in  claim 1 , wherein the particulate separator comprises a hydrocyclone separator.  
     
     
         7 . The lubrication system as recited in  claim 1 , wherein the fluid is obtained from a primary fluid flow produced by the submersible pump.  
     
     
         8 . A method of lubricating a wellbore component with a formation fluid, comprising: 
 producing a fluid from a wellbore formed in a subterranean formation;    within the wellbore, separating particulates from at least a portion of the fluid to obtain a modified fluid; and    directing the modified fluid to a desired lubrication region of a wellbore component.    
     
     
         9 . The method as recited in  claim 8 , wherein producing comprises pumping the fluid with a submersible pump.  
     
     
         10 . The method as recited in  claim 9 , wherein separating comprises separating the particulates downstream of the submersible pump.  
     
     
         11 . The method as recited in  claim 10 , wherein directing comprises routing the modified fluid to a plurality of regions within the submersible pump.  
     
     
         12 . The method as recited in  claim 11 , wherein pumping comprises pumping the fluid with a submersible, centrifugal pump having a pump shaft.  
     
     
         13 . The method as recited in  claim 12 , wherein routing comprises moving the modified fluid through a passageway formed in the pump shaft.  
     
     
         14 . The method as recited in  claim 13 , wherein moving comprises lubricating a plurality of bearings within the submersible pump.  
     
     
         15 . The method as recited in  claim 11 , wherein separating comprises utilizing a hydrocyclone to obtain the modified fluid.  
     
     
         16 . The method as recited in  claim 11 , further comprising maintaining the modified fluid at a pressure higher than the ambient pressure.  
     
     
         17 . A method of lubricating a submersible pump used in a wellbore application, comprising: 
 pumping an oil-based fluid with a submersible pump driven by a pump shaft;    separating particulates from a portion of the oil-based fluid subsequent to pumping to form a modified fluid; and    directing the modified fluid through a passageway in the pump shaft to desired lubrication regions.    
     
     
         18 . The method as recited in  claim 17 , wherein directing comprises directing the modified fluid to a plurality of bearings in the submersible pump.  
     
     
         19 . The method as recited in  claim 18 , wherein separating comprises circulating the portion in a hydrocyclone separator.  
     
     
         20 . The method as recited in  claim 17 , wherein directing comprises moving the modified fluid along an axial passageway in the shaft to a transverse passageway proximate a bearing.  
     
     
         21 . The method as recited in  claim 17 , wherein pumping comprises powering the submersible pump via a submersible motor.  
     
     
         22 . The method as recited in  claim 17 , further comprising maintaining the modified fluid at an internal pressure within the passageway, the internal pressure being greater than ambient pressure.  
     
     
         23 . The method as recited in  claim 22 , wherein directing comprises directing the modified fluid to a plurality of bearings in the submersible pump.  
     
     
         24 . A submersible-pumping system, comprising: 
 a submersible motor;    a submersible pump powered by the motor;    a separator disposed downstream of the submersible pump, the separator being able to separate particulates from at least a portion of the fluid produced by the submersible pump to create a modified fluid; and    a lubrication system disposed to direct modified fluid from the separator to a select region of the submersible pump.    
     
     
         25 . The submersible pumping system as recited in claim,  24 , wherein the submersible pump is a centrifugal pump having a pump shaft.  
     
     
         26 . The submersible pumping system as recited in  claim 25 , wherein the lubrication system comprises a passageway in the pump shaft.  
     
     
         27 . The submersible pumping system as recited in  claim 26 , wherein the passageway comprises an axial portion and a plurality of transverse portions.  
     
     
         28 . The submersible pumping system as recited in  claim 27 , wherein the submersible pump comprises a plurality of bearing areas positioned to receive modified fluid directed through the plurality of transverse portions.  
     
     
         29 . The submersible pumping system as recited in  claim 26 , wherein the modified fluid in the passageway is maintained at a pressure higher than ambient pressure.  
     
     
         30 . The submersible pumping system as recited in  claim 26 , wherein the separator comprises a hydrocyclone separator.  
     
     
         31 . A system for lubricating a submersible pump in a wellbore application, comprising: 
 means for pumping an oil-based fluid with a submersible pump driven by a pump shaft;    means for separating particulates from a portion of the oil-based fluid subsequent to pumping to form a modified fluid; and    means for directing the modified fluid through a passageway in the pump shaft to desired lubrication regions.    
     
     
         32 . The system as recited in  claim 31 , wherein the means for pumping comprises a centrifugal pump.  
     
     
         33 . The system as recited in  claim 31 , wherein the means for separating comprises a particulate separator located downstream of the submersible pump.  
     
     
         34 . The system as recited in  claim 31 , wherein the means for directing comprises a plurality of passageway sections positioned to deliver modified fluid to a plurality of bearings.