Thrust compensation system for fluid transport devices

Abstract

A fluid transport device defining a centerline axis therethrough includes at least one rotatable member including a first portion and a second portion axially opposite the first portion. The fluid transport device also includes at least one stationary member positioned proximate the at least one rotatable member. The at least one rotatable member and the at least one stationary member define at least one stage. The at least one rotatable member defines at least one pressure balance port extending from the second portion to the first portion. The at least one pressure balance port is configured to substantially equalize a fluid pressure proximate the second portion with a pressure of a fluid proximate the first portion.

What is claimed is: 
     
         1 . A fluid transport device defining an axial centerline therethrough, said fluid transport device comprising:
 at least one rotatable member comprising a first portion and a second portion axially opposite said first portion; and   at least one stationary member positioned proximate said at least one rotatable member, wherein said at least one rotatable member and said at least one stationary member define at least one stage, said at least one rotatable member defining at least one pressure balance port extending from said second portion to said first portion, said at least one pressure balance port configured to substantially equalize a fluid pressure proximate said second portion with a pressure of a fluid proximate said first portion.   
     
     
         2 . The fluid transport device in accordance with  claim 1 , wherein said fluid transport device comprises a single stage. 
     
     
         3 . The fluid transport device in accordance with  claim 1 , wherein said fluid transport device is a multi-stage fluid transport device comprising:
 a first stage comprising a first rotatable member and a first stationary member, said first rotatable member comprising a first inlet portion and a first outlet portion axially opposite said first inlet portion; and   a second stage comprising a second rotatable member and a second stationary member, said second stage positioned downstream of said first stage, said second rotatable member comprising a second inlet portion and a second outlet portion axially opposite said second inlet portion, said at least one pressure balance port comprising one or more of:
 a pressure balance port extending between said second outlet portion and said first inlet portion; 
 a pressure balance port extending between said second outlet portion and said second inlet portion; and 
 a pressure balance port extending between said first outlet portion and said first inlet portion. 
   
     
     
         4 . The fluid transport device in accordance with  claim 1 , wherein:
 said at least one rotatable member comprises:
 a rotor shaft; and 
 at least one impeller comprising at least one hub coupled to said rotor shaft, wherein said first portion comprises an at least one impeller inlet portion and said second portion comprises an at least one impeller outlet portion; and 
   said at least one stationary member comprises:
 a casing radially outboard of said at least one impeller, said casing extending over said at least one impeller; and 
 at least one stationary vane coupled to said casing, said at least one stationary vane extending radially inward toward said rotor shaft from said casing. 
   
     
     
         5 . The fluid transport device in accordance with  claim 4 , wherein said at least one stationary vane comprises at least one guide vane and at least one seal member coupled to said at least one guide vane, said casing and said at least one seal member at least partially define a fluid flow path downstream from said at least one impeller outlet portion. 
     
     
         6 . The fluid transport device in accordance with  claim 5 , wherein said at least one seal member, said at least one hub, and said rotor shaft at least partially define a pressure balance cavity coupled in flow communication with said at least one impeller inlet portion through said at least one pressure balance port. 
     
     
         7 . The fluid transport device in accordance with  claim 6 , wherein:
 said at least one impeller outlet portion comprises a first seal extension; and   said at least one seal member comprises at least one second seal extension comprising at least one first seal configured to reduce a clearance between said at least one second seal extension and said at least one first seal extension.   
     
     
         8 . The fluid transport device in accordance with  claim 7 , wherein said at least one seal member further comprises at least one second seal configured to reduce a clearance between said at least one seal member and said rotor shaft. 
     
     
         9 . A thrust compensation system comprising a rotor shaft defining an axial centerline therethrough, said rotor shaft comprising a rotatable hub, said rotatable hub comprising an axially upstream hub portion and an axially downstream hub portion axially opposite said axially upstream hub portion, said at least one rotatable hub defining at least one pressure balance port extending from said axially downstream hub portion to said axially upstream hub portion, said at least one pressure balance port configured to substantially equalize a fluid pressure proximate said axially downstream hub portion with a pressure of a fluid proximate said axially upstream hub portion. 
     
     
         10 . The thrust compensation system in accordance with  claim 9  further comprising at least one seal member positioned proximate said axially downstream hub portion. 
     
     
         11 . The thrust compensation system in accordance with  claim 10  further comprising a rotor shaft coupled to said rotatable hub, wherein said rotatable hub comprises a first seal extension, said at least one seal member comprises at least one second seal extension comprising at least one first seal configured to reduce a clearance between said at least one second seal extension and said at least one first seal extension. 
     
     
         12 . The thrust compensation system in accordance with  claim 11 , wherein said at least one seal member further comprises at least one second seal configured to reduce a clearance between said at least one seal member and said rotor shaft. 
     
     
         13 . The thrust compensation system in accordance with  claim 12 , wherein said at least one seal member, said at least one hub, and said rotor shaft at least partially define a pressure balance cavity coupled in flow communication with said at least one axially upstream hub portion through said at least one pressure balance port. 
     
     
         14 . A fluid transport system configured to pump a multiphase fluid, said fluid transport system comprising:
 a pump driving mechanism;   a fluid conduit; and   a helico-axial pump rotatably coupled to said pump driving mechanism and coupled in flow communication with said fluid conduit, said helico-axial pump defining an axial centerline therethrough, said helico-axial pump comprising at least one stage comprising:
 at least one rotatable member comprising a first portion and a second portion axially opposite said inlet portion; and 
 at least one stationary member positioned proximate said at least one rotatable member, said at least one rotatable member defining at least one pressure balance port extending from said second portion to said first portion, said at least one pressure balance port configured to substantially equalize a fluid pressure proximate said second portion with a pressure of a fluid proximate said first portion. 
   
     
     
         15 . The fluid transport system in accordance with  claim 14 , wherein said helico-axial pump is a multi-stage fluid transport device comprising:
 a first stage comprising a first rotatable member and a first stationary member, said first rotatable member comprising a first inlet portion and a first outlet portion axially opposite said first inlet portion; and   a second stage comprising a second rotatable member and a second stationary member, said second stage positioned downstream of said first stage, said second rotatable member comprising a second inlet portion and a second outlet portion axially opposite said second inlet portion, said at least one pressure balance port comprising one or more of:
 a pressure balance port extending between said second outlet portion and said first inlet portion; 
 a pressure balance port extending between said second outlet portion and said second inlet portion; and
 a pressure balance port extending between said first outlet portion and said first inlet portion. 
 
   
     
     
         16 . The fluid transport system in accordance with  claim 14 , wherein:
 said at least one rotatable member comprises:
 a rotor shaft; and 
 at least one impeller comprising at least one hub coupled to said rotor shaft, wherein said first portion comprises an at least one impeller inlet portion and said second portion comprises an at least one impeller outlet portion; and 
   said at least one stationary member comprises:
 a casing radially outboard of said at least one impeller, said casing extending over said at least one impeller; and 
 at least one stationary vane coupled to said casing, said at least one stationary vane extending radially inward toward said rotor shaft from said casing. 
   
     
     
         17 . The fluid transport system in accordance with  claim 16 , wherein said at least one stationary vane comprises at least one guide vane and at least one seal member coupled to said at least one guide vane, said casing and said at least one seal member at least partially define a fluid flow path downstream from said at least one impeller outlet portion. 
     
     
         18 . The fluid transport system in accordance with  claim 17 , wherein said at least one seal member, said at least one hub, and said rotor shaft at least partially define a pressure balance cavity coupled in flow communication with said at least one impeller inlet portion through said at least one pressure balance port. 
     
     
         19 . The fluid transport system in accordance with  claim 19 , wherein:
 said at least one impeller outlet portion comprises a first seal extension; and   said at least one seal member comprises at least one second seal extension comprising at least one first seal configured to reduce a clearance between said at least one second seal extension and said at least one first seal extension.   
     
     
         20 . The fluid transport system in accordance with  claim 19 , wherein said at least one seal member further comprises at least one second seal configured to reduce a clearance between said at least one seal member and said rotor shaft.