Motor seal

Abstract

A method and apparatus for stabilizing a thrust chamber and circulating fluids within a motor seal is described herein. The apparatus includes a thrust chamber having a thrust runner and a radial bearing. A flow path exists through the radial bearing which stabilizes the thrust runner and circulates fluids in the thrust chamber. The flow path may consist of a plurality of grooves located adjacent to the radial bearing.

1 . An apparatus for sealing and protecting a motor for use in a wellbore, comprising:
 a housing;   a thrust runner configured to fit inside the housing, wherein the thrust runner is substantially cylindrical;   a radial bearing between the thrust runner and the housing; and   one or more grooves between the housing and the thrust runner, wherein the one or more grooves allow a fluid to flow past the radial bearing.   
   
   
       2 . The apparatus of  claim 1 , wherein the radial bearing is a pressurized fluid between the housing and the thrust runner. 
   
   
       3 . The apparatus of  claim 2 , wherein the distance between the thrust chamber and the thrust runner is no greater than 0.002″. 
   
   
       4 . The apparatus of  claim 1 , wherein the one or more grooves are cut into the thrust runner. 
   
   
       5 . The apparatus of  claim 1 , wherein the one or more grooves are cut into the housing. 
   
   
       6 . The apparatus of  claim 1 , wherein the one or more grooves are cut into a combination of the housing and the thrust runner. 
   
   
       7 . The apparatus of  claim 1 , wherein the grooves run substantially parallel to a longitudinal axis of the apparatus. 
   
   
       8 . The apparatus of  claim 1 , wherein the grooves form a spiral pattern past the thrust runner. 
   
   
       9 . The apparatus of  claim 1 , further comprising a first thrust bearing configured to withstand an up thrust on the thrust runner. 
   
   
       10 . The apparatus of  claim 9 , further comprising a second thrust bearing configured to withstand an up thrust on the thrust runner. 
   
   
       11 . The apparatus of  claim 1 , wherein the thrust chamber is a part of a motor seal. 
   
   
       12 . The apparatus of  claim 11 , wherein the motor seal further comprises a one or more fluid reservoirs configured to initially contain a lubricating fluid. 
   
   
       13 . The apparatus of  claim 12 , wherein the lubricating fluid is a dielectric fluid having a lower specific gravity than a wellbore fluid. 
   
   
       14 . The apparatus of  claim 13 , wherein the one or more fluid reservoirs are configured to circulate the lubricating fluid in the motor seal and the housing. 
   
   
       15 . The apparatus of  claim 12 , further comprising a pump coupled to the motor seal, the pump adapted to be driven by the motor which is couple to the motor seal. 
   
   
       16 . The apparatus of  claim 15 , further comprising a drive shaft in the motor seal which is coupled to the motor at one end and the pump at the other. 
   
   
       17 . The apparatus of  claim 16 , wherein the drive shaft travels through an aperture in the thrust runner. 
   
   
       18 . The apparatus of  claim 17 , wherein the aperture has a profiled portion configured to transfer torsion from the drive shaft to the thrust runner. 
   
   
       19 . The apparatus of  claim 11 , wherein the motor is an electric submersible motor. 
   
   
       20 . The apparatus of  claim 15 , wherein the pump is one or more centrifugal pumps. 
   
   
       21 . An apparatus for stabilizing a motor seal for use with an electric submersible pump in a wellbore, the apparatus comprising:
 a motor;   a pump; and   a motor seal configured to absorb a force created by the pump, the motor seal including:
 a drive shaft configured to transfer a torque from the motor to the pump; 
 a thrust chamber including:
 a housing; 
 at least one thrust bearing; 
 a thrust runner configured to transfer the force from the drive shaft to the thrust bearing; 
 a radial bearing between the housing and the thrust runner; 
 a flow path through the radial bearing, wherein the flow path comprises a plurality of grooves configured to move a lubricating fluid within the thrust chamber; and 
 
 one or more seal portions. 
   
   
   
       22 . The apparatus of  claim 21 , wherein the grooves are formed in the thrust runner. 
   
   
       23 . The apparatus of  claim 21 , wherein the grooves are formed in the housing. 
   
   
       23 . The apparatus of  claim 21 , wherein the grooves are formed in both the thrust runner and the housing. 
   
   
       24 . The apparatus of  claim 21 , wherein the grooves form a spiraled pattern. 
   
   
       25 . The apparatus of  claim 21 , wherein the grooves run substantially parallel to the drive shaft. 
   
   
       26 . A method of lubricating the stabilizing a thrust runner, the method comprising:
 actuating an electric motor in a wellbore;   rotating a drive shaft in a motor seal with the electric motor;   transferring the rotation from the drive shaft to a thrust runner;   preventing the thrust runner from wearing against a housing with a fluid pressure between the thrust runner and the housing; and   flowing a lubricating fluid between the thrust runner in a plurality of grooves, wherein the flowing is initiated by the rotation of the thrust runner.   
   
   
       27 . The method of  claim 26 , wherein the flowing of lubricating fluid includes circulating the lubricating fluid toward the electric motor in order to lubricate the electric motor.